Environmental

Consequences
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I NTRODUCTION 235

GENERAL METHODOLOGY FOR ESTABLISHING I MPACT

THRESHOLDS AND MEASURING EFFECTS B Y RESOURCE 237

A QUATIC ORGANISMS 243

WILDLIFE 278

S PECIAL S TATUS S PECIES 294

VEGETATION 335

C ULTURAL RESOURCES 350

VISITOR USE AND E XPERIENCE 369

HUMAN HEALTH 418

S OCIOECONOMIC RESOURCES 425

MANAGEMENT AND OPERATIONS 434

S USTAINABILITY AND L ONG -TERM MANAGEMENT 447

I RREVERSIBLE O R I RRETRIEVABLE C OMMITMENTS

O F RESOURCES 450

A DVERSE I MPACTS THAT C OULD NOT BE AVOIDED 452

Welcome
ENVIRONMENTAL IMPACT STATEMENT 235

INTRODUCTION

his “Environmental Consequences” chapter analyzes both beneficial and

adverse impacts that would result from implementing any of the

alternatives described in this Draft Mountain Lakes Fishery Management Plan /

Environmental Impact Statement (plan/EIS). In addition, this chapter includes a

summary of laws and policies relevant to each impact topic, definitions of impact

“thresholds” (for example, negligible, minor, moderate, and major), methods

used to analyze impacts, and the analysis methods used for determining

cumulative effects. As required by the Council on Environmental Quality (CEQ)

regulations implementing the National Environmental Policy Act (NEPA), a

summary of the environmental consequences for each alternative is provided in

table 15, which can be found in the “Alternatives” chapter. The resource topics

presented in this chapter, and the organization of the topics, correspond to the

resource discussions contained in the “Affected Environment” chapter.

SUMMARY OF LAWS AND POLICIES

Three overarching environmental protection laws and policies guide the actions

of the National Park Service (NPS) in the management of the parks and their

resources—the Organic Act of 1916, NEPA and its implementing regulations,

and the Omnibus Management Act. For a complete discussion of these and other

guiding regulations, refer to the section titled “Related Laws, Policies, Plans, and

Constraints” in the “Purpose of and Need for Action” chapter. These guiding

regulations are described in brief below.

The Organic Act of 1916 (16 USC 1) commits the NPS to making

informed decisions that perpetuate the conservation and protection of park

resources unimpaired for the benefit and enjoyment of future generations.

The National Environmental Policy Act of 1969 is implemented through

regulations of the CEQ (40 CFR 1500–1508). The NPS has, in turn,

adopted procedures to comply with NEPA and CEQ regulations, as found

in Director’s Order 12: Conservation Planning, Environmental Impact

Analysis, and Decision-making (NPS 2001b) and its accompanying

handbook.

The Omnibus Management Act (16 USC 5901 et seq.) underscores NEPA

in that both are fundamental to park management decisions. Both acts

provide direction for connecting resource management decisions to the

T
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236 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

analysis of impacts and communicating the impacts of these decisions to 

the public, using appropriate technical and scientific information. Both acts 

also recognize that such data may not be readily available, and they 

provide options for resource impact analysis should this be the case. 

Section 4.5 of Director’s Order 12 adds to this guidance by stating, “when 

it is not possible to modify alternatives to eliminate an activity with 

unknown or uncertain potential impacts, and such information is essential 

to making a well-reasoned decision, the National Park Service will follow 

the provisions of the CEQ regulations (40 CFR 1502.22).” In summary, the 

NPS must state in an environmental assessment or impact statement 

(1) whether such information is incomplete or unavailable; (2) the 

relevance of the incomplete or unavailable information to evaluating 

reasonably foreseeable significant adverse impacts on the human 

environment; (3) a summary of existing credible scientific adverse impacts 

that is relevant to evaluating the reasonably foreseeable significant adverse 

impacts; and (4) an evaluation of such impacts based on theoretical 

approaches or research methods generally accepted in the scientific 

community. 

Collectively, these guiding regulations provide a framework and process for 

evaluating the impacts of the alternatives proposed in this plan/EIS. 
ENVIRONMENTAL IMPACT STATEMENT 237

GENERAL METHODOLOGY 

FOR ESTABLISHING 

IMPACT THRESHOLDS 

AND MEASURING 

EFFECTS BY RESOURCE 

The general approach for establishing impact thresholds and measuring the 

effects of the alternatives on each resource category includes the following 

elements: 

general analysis methods as described in guiding regulations 

basic assumptions used to formulate the specific methods used in this 

analysis 

thresholds used to define the level of impact resulting from each alternative 

methods used to evaluate the cumulative effects of each alternative in 

combination with unrelated factors or actions affecting park resources 

methods and thresholds used to determine if impairment of specific 

resources would occur under any alternative 

These elements are described in the following sections. 

GENERAL ANALYSIS METHODS 

The analysis of impacts follows CEQ guidelines and Director’s Order 12

procedures (NPS 2001b) and is based on the underlying goal of conserving 

biological integrity in the mountain lake ecosystem. One hallmark of this analysis 

is the application of results of the scientific research conducted in the North 

Cascades National Park Service Complex (North Cascades Complex) along with 

the other best available scientific literature applicable to the region and setting, 

the species being evaluated, and the actions being considered in the alternatives. 

A substantial amount of research has been conducted to answer many of the key 

questions about impacts on the natural resources of the North Cascades Complex. 

In addition, there is a substantial body of research conducted on similar questions 

in other national parks and natural areas. For some species or species groups in 

question, a large number of other studies have been conducted in the region or 

the range of the species. Other research and publications address broader 

ecological issues or landscape-level analysis. 

The North Cascades Complex has been compiling spatial data that includes the 

recorded distribution of various organisms and landscapes. That database has 

been added to, refined, and cross-checked during the impact analysis, and 
E NVIRONMENTAL C ONSEQUENCES

238 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The Technical

Advisory Committee 

provided

recommendations 

to managers of the 

North Cascades 

Complex on matters 

regarding the 

mountain lakes fishery, 

ecosystem status, and

the analysis approach 

for this plan/EIS.

compatible data from other research has been used in conjunction with data from 

the North Cascades Complex. 

The NPS created an interdisciplinary planning team (also referred to as the 

Technical Advisory Committee) comprised of NPS staff from the North 

Cascades Complex, NPS Fisheries Program staff, NPS 

Environmental Quality Division, the Washington 

Department of Fish and Wildlife (WDFW), and other 

individual resource specialists assisting the NPS with 

preparation of this plan/EIS. The team also consulted 

with various experts in the field of fisheries 

management and other applicable scientific studies. 

The committee met periodically throughout the 

analysis and provided important input to the impact 

analysis. 

For each resource topic addressed in this chapter, the 

applicable analysis methods are discussed under each 

resource section. 

ASSUMPTIONS 

Several guiding assumptions were made to provide context for this analysis. 

These assumptions are described below. 

A NALYSIS P ERIOD

This plan/EIS establishes goals, objectives, and specific implementation actions 

needed to manage the mountain lakes fishery for the next 15 years; therefore, the 

analysis period used for assessing impacts is up to 15 years. The impact analysis 

for each alternative is based on the principles of adaptive management, which 

would allow the NPS and WDFW to change management actions as new 

information emerges through monitoring the results of management actions and 

ongoing research throughout the life of this plan/EIS. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The geographic study area for this plan/EIS includes all three administrative units 

of the North Cascades Complex. However, the focus of this document is the 

91 mountain lakes in the North Cascades Complex that have a history of fish 

presence (refer to “Map 1” and the “Map 1 Table” located in the envelope that 

accompanied this document). While management actions are applied to 91 lakes 

in this plan/EIS, the analysis area for analyzing impacts includes streams and 

other lakes connected to the 91 lakes, the terrestrial and cultural resources 

surrounding the lakes, and communities in the vicinity of these lakes. 
General Methodology for Establishing Impact Th resholds and Measuring Effects by Resource

ENVIRONMENTAL IMPACT STATEMENT 239

D URATION AND T YPE OF I MPACTS

For the purpose of the analysis provided in this plan/EIS, the following 

assumptions are used for all impact topics (the terms “impact” and “effect” are 

used interchangeably throughout this document): 

Short-term impacts: Those occurring from fishery management actions in 

the immediate future. 

Long-term impacts: Those occurring from fishery management actions 

over several seasons through the next 15 years and beyond. 

Direct impacts: Those occurring as a direct result of fishery management 

actions, including lake treatment methods. 

Indirect impacts: Those occurring from fishery management actions that 

would indirectly alter a resource or condition. 

F UTURE T RENDS

Visitor use and demand are anticipated to follow trends similar to recent years. 

Visitation to the North Cascades Complex has fluctuated slightly, but generally 

remained at an average of 412,012 people per year between 1996 and 2002. 

In the absence of notable anticipated changes in facilities or access, the average 

visitation is expected to continue and be reflected across user groups. 

IMPACT THRESHOLDS 

Determining impact thresholds is a key component of NPS Management Policies 

(NPS 2001a) and the Director’s Order 12 handbook (NPS 2001b). These 

thresholds provide the reader with an idea of the intensity of a given impact on a 

specific topic. The impact threshold is determined primarily by comparing the 

impact to a relevant standard from state or federal regulations or scientific 

research. Because definitions of intensity vary by impact topic, intensity 

definitions are provided separately for each impact topic analyzed in this 

document. The following intensity definitions are used throughout this analysis: 

negligible, minor, moderate, and major. 

CUMULATIVE EFFECTS ANALYSIS METHOD 

The CEQ regulations that implement NEPA require the assessment of cumulative 

impacts in the decision-making process for federal projects. Cumulative impacts 

are defined as “the impacts on the environment which result from the incremental 

impact of the action when added to other past, present, and reasonably 

foreseeable future actions regardless of what agency (federal or nonfederal) or 

person undertakes such other actions” (40 CFR 1508.7). Cumulative impacts are 

considered for all alternatives, including the no-action alternative (alternative A). 
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240 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Cumulative impacts were determined by combining the impacts of the alternative 

being considered with other past, present, and reasonably foreseeable future 

actions. The following points attempt to clarify potential cumulative impact 

issues in the vicinity of the North Cascades Complex: 

No projects are proposed or in planning stages that would change the road 

access to any unit of the North Cascades Complex. 

No new major trails or trailheads are being considered; however, a small 

section of the Pacific Northwest Trail within the North Cascades Complex 

is currently under construction. 

No new resorts or major upgrades of existing facilities are being planned. 

Visitor use is expected to follow the same patterns that it has for several 

years. 

A climbing management plan is expected in the winter of 2004. 

The park experienced flooding in the fall of 2004, and trails, roads, and 

bridges were destroyed. 

There would be continued logging activities proximate to the park. 

Dam and reservoir operation that has occurred and continues to occur 

outside the North Cascades Complex would have ongoing effects. 

There would be continued human recreational use (by anglers, visitors 

using pack animals [horses, mules, llamas], hikers, and campers) of the 

lakes in the study area and surrounding drainages. The level of use is 

expected to follow recent average visitation. 

There would be a continued presence of fish in lakes located on lands 

surrounding the North Cascades Complex, but these lakes are not 

connected upstream to lakes in the study area. A drop-down of fish from 

lakes outside the North Cascades Complex is not expected. 

There is the potential for increased acid rain from emissions related to the 

development of an additional power plant in the area. 

There would be continued natural impacts (such as erosion, general 

weathering, drought, and flooding). 

There would be continued disturbance to ground resources due to 

inadvertent ground disturbance, vandalism, artifact collection, and digging. 

Based on trends, the economy in communities surrounding the North 

Cascades Complex would continue to evolve as industry diversification 

occurs. 

Park operations costs, in general, are expected to increase based on recent 

trends. 
General Methodology for Establishing Impact Th resholds and Measuring Effects by Resource

ENVIRONMENTAL IMPACT STATEMENT 241

The WDFW manages mountain lake fisheries on lands administered by the U.S. 

Forest Service that surround the North Cascades Complex. The WDFW 

management approach, described in “A Report on the Washington Department of 

Fish and Wildlife’s High Lakes Fishery Management Program” (WDFW 2001), 

is expected to be similar in the foreseeable future to what is currently being done. 

IMPAIRMENT ANALYSIS METHOD 

The “Purpose of and Need for Action” chapter describes the related federal acts 

and policies regarding the prohibition against impairing park resources and 

values in units of the national park system. 

An action constitutes an impairment when its impacts “harm the integrity of park 

resources or values, including the opportunities that otherwise would be present 

for the enjoyment of those resources or values” (NPS 2001a, 1.4.4). To determine 

impairment, the NPS must evaluate “the particular resources and values that 

would be affected; the severity, duration, and timing of the impact; the direct and 

indirect effects of the impact; and the cumulative effects of the impact in 

question and other impacts” (NPS 2001a, 1.4.4). 

NPS units vary based on their enabling legislation, natural and cultural resources 

present, and park missions; likewise, the recreational activities appropriate for 

each unit and for areas in each unit vary as well. For example, an action 

appropriate in one unit would impair resources in another unit. Thus, this 

plan/EIS analyzes the context, duration, and intensity of impacts of the 

alternatives as well as potential for resource impairment, as required by 

Director’s Order #12: Conservation Planning, Environmental Impact Analysis 

and Decision-making (NPS 2001b). An impact on any park resource or value 

may constitute an impairment, but an impact would be more likely to constitute 

an impairment to the extent that it has a major adverse impact upon a resource or 

value whose conservation is necessary to fulfill specific purposes identified in the 

establishing legislation or proclamation of the park 

key to the natural or cultural integrity of the park 

identified as a goal in the park’s general management plan or other relevant 

NPS planning documents 

The following process was used to determine whether the various fishery 

management alternatives had the potential to impair park resources and values: 

Step 1. The enabling legislation, General Management Plan (NPS 1988b), 

Strategic Plan (NPS 2000a), and other relevant background information for the 

North Cascades Complex were reviewed to ascertain its purpose and 

significance, resource values, and resource management goals or desired future 

conditions. 

Step 2. Resource protection goals were identified. 
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242 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Step 3. Thresholds were established for each resource of concern to determine 

the context, intensity, and duration of impacts, as defined earlier in this chapter in 

the section titled “Impact Thresholds.” 

Step 4. An analysis was conducted to determine if the magnitude of impact 

would constitute an “impairment,” as defined by NPS Management Policies 

(NPS 2001a). 

The impact analysis includes findings of impairment of park resources for each 

of the management alternatives. Impairment findings are made for park resources 

affected by the alternatives. Park operations and management, socioeconomics, 

and visitor use are not considered park resources; therefore, impairment findings 

are not included as part of the impact analysis for these topics. 
ENVIRONMENTAL IMPACT STATEMENT 243

Aquatic insects, known 

as macroinvertebrates, 

are important food 

sources for the many 

species of fish that 

dwell in the rivers and 

lakes in the North 

Cascades Complex 

and are also important 

as indicators of water 

quality and habitat 

condition. 

AQUATIC ORGANISMS 

The aquatic organisms potentially affected by the proposed alternatives include 

plankton, macroinvertebrate, and amphibian species that are naturally occurring 

in mountain lakes in the North Cascades Complex, as well as native fish species 

in drainages downstream from the lakes. It is recognized that actions proposed 

under the various alternatives would also have direct impacts on the stocked fish 

themselves, due to a reduction or elimination of selected populations. Stocked 

fish are nonnative species that were stocked specifically for recreational 

purposes; therefore, impacts on stocked fish are not analyzed in detail here, but 

their value to the mountain lakes fishery is addressed in the section titled “Visitor 

Use and Experience” later in this chapter. 

This section explains the methods used to analyze impacts on aquatic organisms, 

presents the results of analysis, and describes the guiding regulations and 

policies, as well as the basic assumptions and thresholds used in the analysis. 

GUIDING REGULATIONS AND POLICIES 

The General Management Plan (NPS 1988b) includes management objectives 

that are relevant to overall natural resources in the North Cascades Complex, 

including aquatic organisms. The General Management Plan includes the 

following objectives: 

To increase knowledge and understanding of the interrelationships of the 

natural processes, and of methods for implementation of appropriate 

actions. 

To preserve, maintain, or restore, where feasible, the primary natural 

resources and ecological relationships and processes. 

To manage the natural resources as an integral part of a regional 

ecosystem. 

To provide opportunity for research in as natural a system as possible. 

The Strategic Plan (NPS 2000a) also includes mission goals for preserving park 

resources that are consistent with the goals and objectives of this analysis. 

Mission Goal I.a. provides for the following desired condition: “Natural and 

cultural resources and associated values of the North Cascades National Park 

Service Complex are protected, restored, and maintained in good condition and 

managed within their broader ecosystem and cultural context.” 

Servicewide NPS regulations and policies, such as the Organic Act of 1916, NPS 

Management Policies (NPS 2001a), and Reference Manual 77: Natural Resource 

Management, also direct parks to provide for the protection of park resources. 

Broadly stated, these policies require the NPS to manage natural resources in a 

manner that will maintain, rehabilitate, and perpetuate the inherent integrity of 

water resources and aquatic systems. In summary, the NPS seeks to 
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244 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

eliminate human-induced impacts on aquatic habitats 

limit effects and mitigate damage if impacts are unavoidable 

maintain and restore aquatic habitats to protect their ecological and 

aesthetic character and dependent plant and animal communities 

METHODOLOGY AND ASSUMPTIONS 

The following section describes the methodology used to evaluate the impacts of 

the proposed alternatives on aquatic organisms. Impacts were assessed by 

considering the major issues identified, examining the existing data and 

literature, and applying professional judgment. Key components of the 

methodology include assumptions made about the extent of the geographic area 

evaluated for impacts, the outcomes of the management actions, and the criteria 

used to evaluate impacts and define impact thresholds for aquatic organisms. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

For the purpose of this analysis, the area evaluated for impacts on aquatic 

organisms includes the 91 naturally formed mountain lakes in the North 

Cascades Complex that currently have, or one time had, a fish presence as a 

result of either documented or undocumented fish stocking activities, as 

described in the “Purpose of and Need for Action” chapter. In the case of stocked 

nonnative fish dispersing downstream and potentially affecting native fish 

species, impacts in downstream drainage basins that extend outside the North 

Cascades Complex are also considered. These drainages include the Chilliwack 

River (Fraser River Basin), Lake Chelan Basin (includes the Stehekin River and 

its tributaries), and the Skagit River and several of its tributaries. 

O UTCOMES OF THE M ANAGEMENT A CTIONS

Several of the management actions that would be applied to lakes under each of 

the action alternatives would potentially have multiple outcomes depending on 

the results of adaptive management decisions. Therefore, for the purpose of this 

analysis, the focus is on the initial outcome of management actions and the 

assumption that the lakes would either have fish or not have fish, based on the 

initial results of the actions taken. However, it is recognized that these conditions 

may change in some of the lakes due to decisions made in the proposed mountain 

lakes fishery monitoring plan (see appendix F). If future monitoring indicates that 

fish presence has caused unacceptable changes to native biota, and as a result fish 

are removed or fish populations are reduced, impacts may also be reduced from 

what is presented here. 
Aquatic Organisms

ENVIRONMENTAL IMPACT STATEMENT 245

Metapopulation: 

Geographically 

separate populations 

of the same species 

connected by 

infrequent, but 

critical, 

interbreeding. 

I MPACT C RITERIA AND M ETHODOLOGY

Information and input from a number of sources were considered during the 

public scoping process. Site-specific research data on the effects of fish stocking 

in North Cascades Complex lakes, as well as additional literature from studies in 

other alpine lake systems, were considered. A concern identified during public 

scoping was that people recognize the adverse impacts on native species in 

mountain lakes from the widespread practice of fish stocking. While fish 

stocking has acknowledged benefits, it can also have negative impacts under 

certain circumstances when nonnative species are stocked, which can result in a 

loss of ecological integrity. 

The methods used to evaluate impacts on aquatic organisms focus on the direct 

and indirect effects of fish populations in mountain lakes, primarily predation and 

competition for prey, effects on food webs and nutrient cycling, and effects on 

native fish resulting from potential downstream colonization by stocked species. 

Both population and community levels were considered. A population is defined 

as the group of individuals within a given species that are reproductively isolated 

from other groups and have geographically defined distributions. Communities 

are defined as the interacting populations of all species within a resource 

category. 

For many aquatic species, such as macroinvertebrates and amphibians, the extent 

of geographic distribution is best described as a metapopulation. This is a cluster 

of geographically discrete populations that are connected by infrequent, but 

critical, interbreeding and genetic exchange with nearby populations. For 

example, the geographic extent of a population of aquatic macroinvertebrates 

with a flying adult phase, such as caddisflies (Trichoptera), is generally 

determined by drainage basin boundaries. However, adult caddisflies from one 

population may frequently disperse to other drainage basins and interbreed with 

other populations, forming a metapopulation relationship. Recolonization of 

suitable habitats where populations are no longer present occurs through similar 

mechanisms. In contrast, populations of purely aquatic zooplankton, such as 

large copepods, are limited to individual lakes or lake clusters that are 

immediately adjacent to each other. 

The units of impact analysis for each group of aquatic organisms are described 

below by resource category. 

Plankton. Effects on plankton are evaluated at both the population and 

community levels, with emphasis on the effects on larger copepod zooplankton 

that are the primary prey species of fish. The plankton community is composed 

of a complex of populations of individual species of both phytoplankton and 

zooplankton that occupy different trophic levels. 

Macroinvertebrates. Effects on macroinvertebrates are evaluated at both the 

population and community levels, with emphasis on the primary prey species of 

aquatic insects. The macroinvertebrate community is composed of a range of 

insect, mollusk, flatworm, nematode, and other species occurring in each lake. 

Some macroinvertebrate species, including aquatic insects, have metapopulations 

that are considered in the analysis. 
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246 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Amphibians. Effects on amphibians are evaluated at the population level, with 

emphasis on the effects on the long-toed salamander, an indicator species that is 

particularly sensitive to fish presence, and the Northwestern salamander, another 

species often found in different lakes than the long-toed salamander. The 

population structure of amphibians varies by species, depending on breeding 

range, adult habitats, and ability to disperse. Metapopulations are important 

considerations in the analysis. 

Fish. Impacts on native fish in downstream drainages are evaluated at the 

population level, for the potential of nonnative trout stocked in mountain lakes to 

establish reproducing “naturalized” populations in streams, where they can affect 

native fish by predation, hybridization, or competition for available habitat and 

resources. The distribution of native fish in basins potentially affected by trout 

introduced to mountain lakes was determined through literature reports of native 

fish distribution (WDFW 2003; Cutler 2001; Smith 2002; Wydoski and Whitney 

2003) and consultation with WDFW biologists (WDFW, M. Downen, pers. 

comm., 2004; WDFW, B. Pfeifer, pers. comm., 2004). 

I MPACT T HRESHOLD D EFINITIONS

Four separate sets of impact thresholds, ranging from negligible to major 

intensity, were defined to address potential impacts on the plankton, 

macroinvertebrates, and amphibians in the mountain lakes and native fish in 

downstream drainages. Because there is incomplete knowledge of the actual 

impacts that are occurring or would occur in all 91 lakes under all four 

alternatives, impact thresholds were developed using predictive factors that have 

been shown to affect the distribution and viability of these organisms. These 

factors were identified from a review of scientific literature and past research. 

For example, past research results indicate that total Kjeldahl nitrogen (TKN) and 

lake connectivity are important predictive factors relating to impacts on 

amphibians. 

In addition to predictive factors, data and professional knowledge supplied by 

NPS and WDFW staff involved in preparing this plan/EIS were used to arrive at 

impact intensities, whenever possible. The assessment was done on a lake-bylake basis, using impact thresholds based on both the predictive factors and 

actual knowledge of site conditions, to arrive at a final impact level for each lake 

and associated downstream drainage. 

Because the impact thresholds used are complex and technical, appendix G 

provides an expanded, detailed discussion of the scientific background material 

that was the basis for impact threshold development. Appendix G also includes 

tables that show the analysis and impact results on a lake-by-lake basis for each 

group of aquatic organisms (see tables G-1, G-2, G-4, and G-5). A summary of 

the impact thresholds and the main factors considered in their development is 

provided in table 31. 
ENVIRONMENTAL IMPACT STATEMENT 247

TABLE 31: SUMMARY OF IMPACT 

THRESHOLDS – AQUATIC 

ORGANISMSa

Impact Intensity Primary Predictive Factorsb

Affecting Impact Levels Negligible Minor Moderate 

Plankton (primarily large zooplankton species)• Fish densityc (higher trout 

densities may result in greater 

predation of zooplankton) 

• Lake depth (plankton can 

escape predation in deeper lakes) 

• Lake area (plankton can 

escape predation in larger lakes) 

• Professional knowledge of 

study area lakes 

• Impacts on larger zooplankton 

(copepods) are of primary concern since they are more susceptible to predation by fish than are small zooplankton. 

Long-term adverse impacts would potentially be negligible even though these lakes have historically been stocked. Abundance and community structure would be expected to be influenced primarily by biogeographical and evolutionary processes. For this assessment, negligible impacts on the zooplankton community would be expected in a lake where the following predictive factor is found: • Lake was previously stocked 

but is currently fishless 

Minor changes in community structure would potentially occur. If fish were removed or died off, the community structure would become comparable to currently fishless lakes. For this assessment, minor impacts on the zooplankton community would be expected in a lake where the following predictive factors are found: • Lake depth >50 ft., OR 

• Lake area >40 ac., OR • Fish density is low (stocked 

trout at <100 fish/acre or reproducing trout at <50 trout/acre) 

Noticeable changes in community structure would potentially occur, and large copepod abundance would be greatly reduced. If fish were removed or died off, the relative abundance of large copepods would increase. For this assessment, potentially moderate impacts on large zooplankton would be expected in a lake where the following predictive factors are found: • Lake depth <50 ft. 

AND

• Lake area <40 ac.

AND

Fish density is high 

(reproducing trout at 50 fish/acre) 

Signcompotecopereduthey were combecofishleasseimpawouwhefacto• L

ALAF

(a>

Macroinvertebrates (primarily aquatic insects – mayflies, stoneflies, caddisflies, and midges)• Fish densityc (higher trout 

densities result in greater predation of macroinvertebrates) 

• Lake area (macroinvertebrates can escape 

predation in larger lakes) 

• Professional knowledge of 

study area lakes (especially the presence/absence of habitat complexity) 

Community structure would be comparable to fishless lakes with similar physical/chemical characteristics. Abundance and community structure would be expected to be influenced primarily by biogeographical and evolutionary processes. For this assessment, negligible impacts on the macroinvertebrate community would be expected in a lake where the following predictive factor is found: • Lake was previously stocked 

but is currently fishless 

Minor changes in community structure in a lake would potentially occur; although populations would recover if fish were removed. For this assessment, minor impacts would be expected where the following predictive factor is found: • Fish density is low (stocked 

trout at <100 fish/acre) 

Moderate changes in community structure and functional group composition in a lake would potentially occur, relative to currently fishless but otherwise similar lakes. Populations eventually would recover from impacts if fish were removed. For this assessment, moderate impacts would be expected where the following predictive factors are found: • Fish density is high (stocked 

trout at >100 fish/acre or reproducing trout at >50 fish/acre) 

Majohigh absetaxa occuenviAddiin dofeedwoumighperiointerassewoufollowfoun
TABLE 31: SUMMARY OF IMPACT 

THRESHOLDS – AQUATIC 

ORGANISMSa (CONTINUED) 

248 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN Impact Intensity Primary Predictive Factorsb Affecting Impact Levels Negligible Minor Moderate 

Macroinvertebrates (continued) (primarily aquatic insects – mayflies, stoneflies, caddisflies, and midges) AND Lake area >10 acres OR • Lake area <10 acres with high habitat complexity • F

trf

A

Lw

Amphibians (represented by long-toed salamanders and Northwestern salamanders) • Fish densityc (higher trout densities result in greater predation of amphibians) • Presence of nearby forested habitat suitable for either principal species of interest: long-toed salamanders – open terrain at the lake with forest nearby; Northwestern salamanders - dense, closed- canopy forest • TKNd levels (higher TKN means higher lake productivity that, in turn, correlates with more long-toed salamanders) • Degree to which lakes are connected (higher Index of Connectivity [IOC]e means lakes are more connected and can therefore more easily recolonize and recover from impacts) • Professional knowledge of study area lakes • Impacts on long-toed salamanders are of primary concern because of their sensitivity to fish predation Populations likely would be present in any lake in historic range, with larval density close to that of fishless lakes. For this assessment, negligible impacts on long-toed salamanders would be expected where the following predictive factors are found: • Lake with suitable habitat is within their range AND TKN ≥ 0.045 mg/L, fish density is low, and IOC ≥ 0.4 OR • Lake with suitable habitat is within their range AND TKN < 0.045 mg/L and fish density is low OR • Lake with suitable habitat is within their range AND TKN < 0.045 mg/L, fish density is high, and IOC > 0.7 Populations likely would be present in their historic range, but density of larvae in a lake would potentially be slightly smaller than comparable fishless lakes. For this assessment, minor impacts on long-toed salamanders would be expected where the following predictive factors are found: • Lake with suitable habitat is within their range AND TKN ≥ 0.045 mg/L, fish density is low, and IOC < 0.3 Minor impacts on Northwestern salamanders may occur when the following predictive factors are found: • Lake with suitable habitat is within their range AND Stocked fish density is low Populations would be present in the historic range, but density of larvae in a lake would potentially be smaller than comparable fishless lakes, and populations may be eliminated on a temporary or local basis. Populations would deviate from normal levels. For this assessment, potentially moderate impacts on long-toed salamanders would be expected where the following predictive factors are found: • Lake with suitable habitat is within their range AND TKN ≥ 0.045 mg/L, fish density is high, and IOC ≥ 0 OR • Lake with suitable habitat is within their range AND TKN < 0.045 mg/L, fish density is high, and IOC = 0.4–0.6 Popu

sala

permlevefrom unlikpotelong

expepred• L

wA

T

d

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• L

wA

T

d

Majosala

lake behaavoi
TABLE 31: SUMMARY OF IMPACT 

THRESHOLDS – AQUATIC 

ORGANISMSa (CONTINUED)

ENVIRONMENTAL IMPACT STATEMENT 249 Impact Intensity Primary Predictive Factorsb Affecting Impact Levels Negligible Minor Moderate 

Amphibians (continued) (represented by long-toed salamanders and Northwestern salamanders) Moderate impacts on Northwestern salamanders may occur when the following predictive factors are found: • Lake with suitable forested habitat is within their range AND Fish density is high Native Fish • Connections to downstream streams and creeks containing native fish (there must be a connection for impacts on occur) • Particular fish species/strains present (some, like brook trout, are more aggressive; some like Mt. Whitney and California golden trout, do not readily colonize downstream areas; some are not able to interbreed) • Specific professional (primarily WDFW) knowledge of potentially affected outlet stream reaches If present in a lake with an outlet, fish are either native to basin or are unlikely to colonize downstream areas if one or more of the following predictive factors apply. • Ross Lake or Mt. Whitney rainbow trout, coastal cutthroat trout, or California golden trout are present in a west-side lake OR • Westslope cutthroat trout are present in an east-side lake OR • The lake is fishless Relatively small numbers of individuals would potentially be affected through intra-species hybridization. Outbreeding depression may occur in vicinity of outlet stream, but effects would be localized. All native species would be indefinitely viable. For this assessment, potentially minor impacts would be expected when a surface outlet connects to a downstream basin AND one of the following additional predictive factors is found: • Reproducing strains or subspecies of rainbow or cutthroat trout not native to basin are present in a west- side lake OR • Mt. Whitney rainbow trout are stocked in an east-side lake Although individuals of non- native species stocked in a lake would occasionally disperse downstream and rear in streams, there would be no measurable evidence of colonization or hybridization with native fish. All native species would be indefinitely viable. For this assessment, potentially moderate impacts would be expected when a surface outlet connects to a downstream basin AND the following additional predictive factors are found: • Inventories demonstrate that colonization and/or hybridization of the outlet stream has not occurred from populations of nonnative stocked fish that have a long history of high levels of reproduction AND • Reproducing brook trout are present in a west-side lake OR • Reproducing rainbow trout or rainbow/cutthroat hybrids are present in an east-side lake Ther

evidwhehybrNativnormabunpermbasielimswarpotebe eoutlebasiaddifoun• I

chsdsA

R

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• R

rp
TABLE 31: SUMMARY OF IMPACT 

THRESHOLDS – AQUATIC 

ORGANISMSa (CONTINUED) 

250 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN Notes: a. For detailed thresholds and background information about their development, see appendix G. b. Predictive Factors = Physical, chemical, and biological factors are used in this assessment as surrogates indicative of potential impacts on organism

available, depth and TKN values are estimated from knowledge of similar nearby lakes. c. Low fish density < 100 trout/acre for stocked fish or < 50 trout/acre for reproducing fish. High fish density > 100 trout/acre for stocked fish or > 50 trout/acre for reproducing fish. Very High fish density > 400 trout/acre of reproducing fish or stocked fish with multiple-year classes approximating age structure of reproducing fish. d. TKN = Total Kjeldahl nitrogen (combined measurement of ammonia and organic nitrogen). e. IOC = Index of Connectivity (based on the number of known salamander populations within 3.75 miles and the number of potential long-toed salam

0.4 mile). Symbols: < = less than > = greater than 

≥ = greater than or equal to ≤ = less than or equal to 
Aquatic Organisms

ENVIRONMENTAL IMPACT STATEMENT 251

In addition to discussing impacts related to stocking, the analysis also provides a 

discussion of impacts related to proposed lake treatment methods. For these 

impacts, no specific impact threshold definitions were developed; rather, these 

effects were evaluated using literature review, professional experience, and best 

professional judgment. Similarly, beneficial effects that are not defined in the 

thresholds are identified where appropriate, using best professional judgment. 

In all cases, an evaluation of impairment was performed, as described below, to 

determine if any major impacts would be considered an impairment. 

Impairment. Major impacts on an aquatic resource or value that, due to its 

severity, duration, and/or timing, would result in the elimination of an aquatic 

species in the North Cascades Complex or would result in significant population 

declines in an aquatic species. In addition, these major adverse impacts on North 

Cascades Complex resources and values would 

contribute to deterioration of aquatic resources and values to the extent that 

the purpose of the North Cascades Complex would not be fulfilled as 

established in its enabling legislation 

affect resources key to the natural or cultural integrity or opportunities for 

enjoyment in the North Cascades Complex 

affect the resource whose conservation is identified as a goal in the 

General Management Plan (NPS 1988b) or other planning documents for 

the North Cascades Complex 

IMPACTS OF THE 

ALTERNATIVES ON AQUATIC ORGANISMS 

This section addresses impacts that would result from the implementation of the 

management actions for each of the lakes under each alternative; the impacts are 

related to the numbers of stocked or reproducing fish that would remain in the 

subject lakes and to any treatment method used to remove fish (except for 

alternative A because no lakes are currently treated for fish removal). Table 32 

summarizes the predicted impact levels by alternative for each group of aquatic 

organisms (by numbers of lakes) related solely to the management action 

outcomes. 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A would continue existing practices in the 91 lakes slated for 

management consideration in the study area. For more information on the 

91 lakes, refer to table 5 and figure 4 in the “Alternatives” chapter and 

appendix E. 
E NVIRONMENTAL C ONSEQUENCES

252 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

TABLE 32: OUTCOMES OF APPLYING AQUATIC ORGANISM IMPACT THRESHOLDS

(NUMBERS OF LAKES FALLING INTO THE 

DIFFERENT IMPACT THRESHOLDS UNDER EACH ALTERNATIVE) 

Plankton Alternative A Alternative B Alternative C Alternative D 

Major 1

a 0 0 0 

Moderate 13 0 0 0 

Minor 48 29 9 0 

Negligible 29 62 82 91 

a. Blum (Lower/West No. 4) Lake: Major impact based on very high fish density, 25.9 foot depth, 

6.4 acre area. 

Macroinvertebrates Alternative A Alternative B Alternative C Alternative D 

Major 13b 0 0 0 

Moderate 17 0 0 0 

Minor 32 29 9 0 

Negligible 29 62 82 91 

b. These lakes include Battalion, Berdeen (Upper), Berdeen (Lower), Blum (Lower/West No. 4), Dee 

Dee (Upper), Diobsud No. 1, Diobsud No. 2 (Lower), Diobsud No. 3 (Upper), Doug’s Tarn, Kettling, 

Stiletto, Triplet (Lower), and Wilcox/Sandie (Lower): Lakes with major impacts based on current 

monitoring data or predictive factors of high fish densities and relatively small lake areas. 

Amphibians Alternative A Alternative B Alternative C Alternative D 

Major 7

c 0 0 0 

Moderate 11 0 0 0 

Minor 15 9 5 0 

Negligible 58 82 86 91 

c. These lakes include Battalion, Blum (Lower/West, No. 4), Blum (Largest/Middle, No. 3), Dee Dee 

(Upper), and Hanging: Major impacts based on high fish density, TKN <0.045 mg/L or unknown, 

Index of Connectivity (IOC) <0.3 or unknown (conservative estimates); plus Sourdough and Triplet 

(Lower) lakes: Major impacts based on high fish density, TKN >0.045 mg/L or unknown, IOC <0. 

Native Fish Alternative A Alternative B Alternative C Alternative D 

Major 1

d 0 0 0 

Moderate 9 0 0 0 

Minor 26 7 1 0 

Negligible 55 84 90 91 

d. McAlester Lake: Major impacts based on presence of nonnative rainbows in east-side lake, with 

evidence of both colonization and hybridization (note: impacts on native westslope cutthroat trout are 

addressed in the “Special Status Species” section.
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 253

Plankton: “Freefloating” organisms 

that include 

phytoplankton (freefloating microscopic 

plants) and 

zooplankton (the 

animal counterparts of

phytoplankton). 

Copepod: A type of 

crustacean 

zooplankton that 

exhibits a wide variety 

of feeding preferences, 

even consuming other 

zooplankton. The 

larger copepods are 

an important 

component of the food 

base for larger 

vertebrate organisms 

such as larval 

amphibians and fish. 

Impacts of Current Fish 

Stocking on Aquatic Organisms 

Plankton. Under alternative A, the extent of impacts on the plankton community 

from stocking would vary considerably from lake to lake. Direct and indirect 

effects resulting from fish predation and changes in nutrient cycling would occur 

in varying magnitude in each lake, depending on the population characteristics 

(such as fish density and whether the lake is stocked or has mixed or reproducing 

populations) and the physical characteristics of each lake. Table 31 summarizes 

the thresholds used in identifying impact levels for plankton under each 

alternative, and appendix G provides a more detailed discussion about the 

predictive factors and the thresholds. Table G-1 in appendix G provides an 

assessment of impacts on plankton by lake for each alternative. 

As shown in table 31, the primary concerns in the analysis of impacts on 

plankton are impacts on larger copepods, which tend to be more susceptible to 

predation by fish. Factors considered in the analysis include fish density (defined 

for both stocked and reproducing populations), lake depth, and lake area, as well 

as professional knowledge of the lakes and plankton dynamics. 

Based on the thresholds established, only 1 of the 91 lakes in the study area 

would be expected to experience long-term, major, adverse impacts on plankton 

from current management actions. This is Blum (Lower/West No. 4), which has a 

very high density of reproducing fish and a relatively small size and depth (see 

table G-1 in appendix G). Research indicates that zooplankton species can be 

adversely affected by predation and changes in food web dynamics resulting 

from the introduction of fish, especially when high densities of reproducing fish 

are present. In some cases, it has been observed that fish stocking has resulted in 

the complete extirpation of some species, with larger copepods and cladocerans 

being the most vulnerable (Parker et al. 1996, 2001; Anderson 1972; Crumb 

1978; Divens et al. 2001; Leavitt et al. 1994). However, research has shown that 

zooplankton were not extirpated in larger, deeper lakes (greater than 50 feet in 

depth), even lakes with high densities of stocked fish, because the deeper zones 

provide refuge habitat for the large copepod and cladoceran species that are most 

vulnerable to extirpation (Donald et al. 1994). Therefore, adverse impacts on 

plankton are more likely to be present and/or more severe in shallow lakes with 

very high fish densities, such as Blum (Lower/West No. 4). 

Moderate long-term adverse impacts on plankton would be expected to occur in 

14 of the 91 lakes in the study area. These 14 lakes have high fish densities 

(although not as high as seen in Blum Lower/West No. 4), are relatively shallow 

(less than 50 feet deep) or assumed to be shallow, and are relatively small (less 

than 40 acres). Impacts in these lakes would be similar to those expected in Blum 

(Lower/West No. 4) and would likely include a decrease in large copepod 

abundance, as well as changes in nutrient cycling and associated phytoplankton 

community changes. However, because the densities of fish in these 14 lakes are 

not extremely high, impacts would be considered moderate. 

In 48 of the 91 lakes, impacts on plankton would be considered adverse, minor, 

and long term. Fourteen of the 48 lakes have high-density reproducing fish 

populations, but the lakes are sufficiently large and deep to provide refuge 

habitat. Lakes greater than 50 feet deep provide shelter for larger zooplankton, 
E NVIRONMENTAL C ONSEQUENCES

254 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

which limits the severity of impacts from introduced fish (Donald et al. 1994). 

The remainder of the 48 lakes support low-density stocked, mixed, or 

reproducing populations, which have been shown to have limited impacts on the 

plankton community. Several studies have shown that plankton can survive in 

lakes that contain lower densities of fish, especially if the fish are 

nonreproducing. Studies of mountain lakes in the Olympic and Cascade 

mountains found that one large zooplankton species continued to coexist with 

low densities of reproducing trout more than 20 years after the initial introduction 

(WESI 1993). Other studies have documented the coexistence of large 

diaptomids with low densities of reproducing salmonids (Hoffman and Pilliod 

1999; Bahls 1990; Anderson 1972; McNaught et al. 1999). In the lakes with lowdensity populations of stocked fish, population structure and abundance may vary 

slightly for some plankton species because of the indirect effects of fish presence 

on food web dynamics and nutrient cycling. Populations of large zooplankton, 

which are preyed upon by stocked trout, may be slightly suppressed, but remain 

viable and healthy. Shifts in phytoplankton community structure resulting from 

fish stocking would persist, but it is unlikely that species would be eliminated, 

and the resilience and adaptive capacity of the community would be maintained. 

For these reasons, impacts on the plankton community in these 48 lakes would be 

considered minor. 

In the 29 fishless lakes, long-term adverse impacts on plankton would 

be considered negligible. These lakes were historically stocked with 

trout but currently have no fish populations. Research has shown that, 

with time, plankton communities can recover in lakes that have 

contained fish, and zooplankton can be effectively reintroduced 

(McNaught et al. 1999; Parker et al. 2001). Also, phytoplankton 

species generally are not lost entirely, although there may be a shift in 

species abundance and community structure that persists following 

fish removal (Drake and Naiman 2000). While community structure in 

these lakes may have shifted from historical conditions prior to fish 

stocking, the range of plankton species present and overall biomass 

and productivity in these 29 lakes would be expected to be comparable to those 

in similar, but otherwise fishless lakes. Therefore, residual adverse impacts of 

fish stocking in these lakes would be considered negligible because recovery has 

occurred. These lakes serve as a benchmark for expected conditions in lakes 

following a period of recovery after fish are removed. 

Impairment of plankton species across the study area would not occur under 

alternative A. 

Macroinvertebrates. The assessment of impacts on the macroinvertebrate 

community under alternative A was based primarily on fish density and lake 

area, relying heavily on the data and professional knowledge of NPS staff who 

have been monitoring macroinvertebrates in several study area lakes over several 

years (NPS, R. Glesne, pers. comm., 2004). Table 31 provides a summary of 

impact thresholds for macroinvertebrates, while appendix G provides additional 

background information used to develop the thresholds. Table G-2 in appendix G 

provides an assessment of impacts on macroinvertebrates by lake and by 

alternative. 

Talus Tarn is one of the 

29 currently fishless 

lakes that would

remain fishless 

under all alternatives.
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 255

In 13 of the 91 lakes, impacts on macroinvertebrates under alternative A are 

expected to be adverse, long term, and major. Four of these lakes are included in 

the current NPS benthic macroinvertebrate monitoring program. The major 

impact level for these four lakes was assigned based on monitoring data that 

shows an absence of more than 40% of the taxa expected to commonly occur in 

fishless lakes of similar environmental characteristics. For 9 of the 13 lakes, a 

major impact level was predicted due to the presence of high densities of 

nonnative fish (greater than 100 fish/acre for stocked lakes, greater than 50 

fish/acre for lakes with reproducing fish), combined with a relatively small area 

(less than 10 acres) and a lack of complex habitat as defined and identified by 

NPS biologists familiar in this lake (NPS, R. Glesne, pers. comm., 2004). In 

these lakes, high densities of fish would result in more intense fish predation, 

which has been shown to result in substantial changes in abundance and biomass 

of some species, as well as phenotypic (visible characters of an organism) and 

behavioral changes (Chess et al. 1993; Knapp 1996; Luecke 1990; Walters and 

Vincent 1973). Some species may be depressed or even extirpated in some lakes. 

In 17 of the 91 lakes, stocking would be expected to result in long-term, 

moderate, adverse impacts on macroinvertebrates. These lakes contain a high or 

very high density of stocked or naturally reproducing fish populations that prey 

on macroinvertebrates, but the lakes are larger (greater than 10 acres) and/or have 

a more complex or diverse habitat. Macroinvertebrate community structure in 

these 17 lakes would likely differ from fishless but otherwise similar lakes, as 

well as lakes with lower-density fish populations, but populations would recover 

if fish were removed. 

In 32 of the 91 lakes, impacts on macroinvertebrates would be considered 

adverse, minor, and long term. These lakes have low-density stocked or mixed 

stocked/reproducing fish populations, which would have much reduced predation 

pressure on the macroinvertebrate community. Research has shown that while 

higher densities of stocked trout (716 to 1,790 fish/acre) can have substantial 

impacts on macroinvertebrate populations (Reimers 1958), lower densities of 

stocked trout (less than 100 fish/acre) have little effect on benthic fauna 

(Hoffman and Pilliod 1999). Predation and alteration of food web dynamics in 

these lakes would be expected to result in minor local reductions in 

macroinvertebrate abundance. Some shifts in community structure may also 

occur, but these would be minor relative to overall population structure. 

In the 29 lakes that are now fishless, long-term adverse impacts on 

macroinvertebrates would be considered negligible. These lakes were historically 

stocked with trout but currently have no fish populations. Observed 

macroinvertebrate community structure and abundance in these lakes would be 

expected to be comparable to those in similar, but otherwise fishless lakes, 

indicating that a recovery has occurred. As the literature indicates, the primary 

prey macroinvertebrate species are relatively resistant to fish predation at the 

population and community levels in lake environments, with the exception of 

sensitive species such as phantom midges (Chaoborus spp.). As previously 

mentioned, affected species usually have a high dispersal potential, and therefore, 

lakes can be recolonized relatively quickly (Bilton et al. 2001; Bohonak and 

Jenkins 2003), so that the residual adverse effects of fish stocking in these lakes 

would be considered negligible. 
E NVIRONMENTAL C ONSEQUENCES

256 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The Index

 of Connectivity 

(IOC) is based on 

the number of known 

salamander

populations within 

3.75 miles of a study 

area lake and the 

number of potential

long-toed

salamander

breeding ponds 

within 0.4 mile.

Impairment of macroinvertebrate species across the study area would not occur 

under alternative A. 

Amphibians. The analysis of impacts on amphibians is focused on two species: 

the long-toed salamander and the Northwestern salamander. These two species 

are sensitive to fish predation and generally not found together in the same lakes 

in the North Cascades Complex. Since there are limited data available on 

salamander presence, abundance, and viability in all 91 lakes in the study area, 

impacts were assessed based on several predictive factors taken from the 

literature and research. These factors, in various combinations, tend to correlate 

with certain observed levels of impacts. The factors include fish density, total 

Kjeldahl nitrogen (TKN), and lake connectivity, as well as availability of suitable 

habitat. 

Table 31 summarizes the impact thresholds for amphibians, based on the 

predictive factors. Appendix G provides more detail concerning the factors used 

in the thresholds. Table G-3 in appendix G provides an assessment of impacts on 

amphibians by lake for each alternative. Generally, impacts would be expected to 

be high if TKN levels are high, the Index of Connectivity (IOC) is low, and 

densities of fish in a lake are high. If, for instance, densities of fish are low or the 

IOC is particularly high for a lake or if TKN levels are low, the impact would be 

reduced. In some cases where data for one or more of the predictive factors were 

missing, a conservative estimate was made. Impacts would be less than predicted, 

and future monitoring (see appendix F) would be used to determine the impacts 

and take appropriate management actions in the future. 

Based on the thresholds developed, in 7 of the 91 lakes in the study area, impacts 

on long-toed salamanders would be expected to be adverse, major, and long term. 

These lakes have high densities of reproducing trout with various combinations 

of low TKN levels and/or low IOC values, all of which are associated with 

declines in amphibian numbers. As research has shown, long-toed salamanders 

are at risk of extirpation in low-productivity lakes (TKN values less than 

0.045 mg/L) with high-density fish populations (greater than 100 fish per acre) 

(Liss et al. 1995, 1999, 2002). Also, a low connectivity with other lakes indicates 

a reduced possibility of recovery of local populations that may be extirpated, 

since there are few nearby subpopulations to serve as sources for recolonization 

of the affected lake. Six of the 7 lakes do not have recorded values for TKN and 

have been assigned a major impact based on the possibility of low TKN values. 

If subsequent research shows that TKN values in these lakes are high, the level of 

impacts would be reduced. 

In 11 of the 91 lakes, impacts on amphibians would be expected to be adverse, 

moderate, and long term, based on the thresholds established. Three of these 

lakes have high densities of reproducing trout and are within the range of 

Northwestern salamanders. Research has shown that the Northwestern 

salamander can coexist with high densities of reproducing trout and still remain 

viable, although at measurably reduced larval densities (Larson and Hoffman 

2002; Hoffman et al. 2003). This is likely due to the large size of the older larvae 

and adults in this species, as well as changes in their behavior in the presence of 

fish (they become active only at night and stay close to the shore or other escape 

cover) (Brokes 1999; Hoffman et al. 2003; Larson and Hoffman 2002). Eight of 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 257

the 11 lakes are within the range of long-toed salamanders, and all have various 

combinations of either high IOC values or high TKN values combined with high 

densities of reproducing trout, which contribute to moderate impacts. 

In 15 of the 91 lakes, impacts on amphibians would be expected to be adverse, 

minor, and long term. Three of the 14 lakes are within the range of Northwestern 

salamanders but have low densities of trout. Research has shown that the 

Northwestern salamander can coexist with low densities of reproducing trout 

with slightly reduced larval densities (Hoffman et al. 2003). This is likely due to 

the large size of the older larvae and adults in this species, as well as changes in 

their behavior in the presence of fish (Brokes 1999; Hoffman et al. 2003; Larson 

and Hoffman 2002). Twelve of the 15 lakes are within the range of long-toed 

salamanders but have low densities of trout, causing the impacts to be minor. 

Three of these 12 lakes do not have recorded values for TKN and have been 

assigned a minor impact based on the possibility of high TKN values. If 

subsequent research shows that TKN values in these lakes are low, the level of 

impacts would be reduced. 

In 58 of the 91 lakes, long-term adverse impacts on amphibians would be 

negligible. Twenty-nine of the 58 lakes are fishless and, therefore, have no 

impacts on salamanders from stocked fish. Of the remaining 29 lakes, 20 have 

fish but do not have salamanders because they are either outside the distribution 

of salamanders in the North Cascades Complex or do not have suitable aquatic or 

terrestrial habitat for long-toed or Northwestern salamanders. Eight lakes are 

within the range of long-toed salamanders, but contain low densities of stocked 

trout with various combinations of TKN values and IOC values that indicate that 

long-toed salamanders should be able to survive and do well, given the lower fish 

densities, available nitrogen, and lake connectivity. One lake has a low density of 

trout, but does not have a recorded TKN value, so it has been assigned a 

negligible impact because it has an IOC of 0.8. 

Impairment of amphibian species across the study area would not occur under 

alternative A. 

Native Fish. Impacts on native fish populations were assessed using the 

professional knowledge of both NPS and WDFW staff involved in preparing this 

plan/EIS, who have direct experience and/or data regarding the status of native 

fish in many study area drainages. Where data were lacking, impacts were 

assessed based on predictive factors that include the particular species of trout 

reproducing or stocked in a lake and the type of native fish present in the 

downstream watershed. Also, specific knowledge of the extent of colonization 

and hybridization, as provided by WDFW biologists familiar with study area 

streams, was used to determine if major impacts existed. 

Table 31 summarizes the predictive factors for native fish used in the assessment, 

while appendix G provides a more detailed discussion of the impact thresholds. 

Table G-5 in appendix G provides an assessment of impacts on native fish by 

lake for each alternative. 

In one of the 91 lakes (McAlester), long-term adverse impacts on downstream 

native fish communities from reproducing populations of fish would be 
E NVIRONMENTAL C ONSEQUENCES

258 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The WDFW refers to

bull trout and Dolly

Varden char

collectively as “native

char” because the two

species are impossible

to reliably distinguish

between without

genetic analysis.

considered major. This lake has a surface outlet connecting to its downstream 

drainage and contains a high density of reproducing hybrid rainbow/cutthroat 

trout not native to the downstream watershed. Also, it is known that both 

colonization and hybridization have occurred with downstream native westslope 

cutthroat trout (WDFW, M. Downen, pers. comm., 2004). Research indicates that 

native fish communities in watersheds below mountain lakes can be adversely 

affected if salmonids stocked into mountain lakes colonize downstream outlets 

and hybridization occurs. Other impacts can occur through competition for 

resources (competition for food or for spawning habitat) and predation on 

juvenile native fish. 

In 9 lakes, adverse impacts on downstream native fish would be 

considered moderate. In these lakes, there are reproducing brook trout in 

a west-side lake and reproducing rainbow trout in an east-side lake. 

These predictive factors indicate a potential for major impacts, but 

neither colonization nor hybridization has occurred in the outlet streams; 

therefore, impacts are considered moderate (WDFW, M. Downen, pers. 

comm., 2004). Introductions of brook trout or closely related taxa of nonnative 

trout (Oncorhynchus sp./spp.) can have drastic consequences on native salmonids 

in watersheds throughout western North America (Behnke 1992; Gresswell and 

Varley 1988; Stoltz and Schnell 1991; Trotter 1987). Brook trout are especially 

aggressive and can traverse high-gradient stream reaches to colonize tributaries. 

They can also compete with native trout for available resources in headwater 

streams and tributaries (Adams et al. 2001). It has been documented that stocked 

rainbow trout replace native populations of westslope cutthroat trout throughout 

its native range, either through competition or hybridization (Behnke 1992). 

Westslope cutthroat trout are not native to west-side stream basins and have the 

potential to compete with native trout and coho salmon for resources, prey on 

juvenile native char, and hybridize with coastal rainbow and cutthroat trout 

(WDFW, M. Downen pers. comm., 2004). Future monitoring would help to 

validate this assessment. 

In 26 of the 91 lakes, impacts on downstream native fish communities from 

stocked fish are expected to be adverse, minor, and long term. Five of these lakes 

are west-side lakes that contain populations of nonnative strains of reproducing 

rainbow trout (WDFW, M. Downen, pers. comm., 2004), which may adversely 

affect downstream populations of native char and trout. Seven of these lakes are 

east-side lakes that contain stocked populations of Mt. Whitney rainbow trout. 

This strain has a very limited potential for downstream dispersal and, on the east 

side of the Cascade Crest, rainbow trout do occur as a native species. Therefore, 

any downstream dispersal would have limited potential for hybridization. The 

remainder of the 26 lakes have reproducing nonnative westslope cutthroat in 

west-side lakes. This presents a minor impact because westslope cutthroat trout 

reproduce later than native salmonids, and this restricts the potential for 

hybridization. 

In 55 of the 91 lakes, adverse impacts on downstream native fish communities 

from stocked fish would be considered negligible. In 26 of these lakes, either no 

surface outlet exists, or the trout that are present are native to the watershed in 

which the lake is located. For example, if westslope cutthroat trout were stocked 

in an east-side lake or coastal cutthroat trout were stocked in a west-side lake, it 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 259

is very unlikely that the stocked trout would establish reproducing populations in 

outlet streams or contribute to the hybridization of native populations of coastal 

rainbow and cutthroat trout. Neither the Mt. Whitney nor the California golden 

strains are likely to disperse downstream, or if that would occur, it would likely 

be self-limiting due to ineffective competition (WDFW, B. Pfeifer, pers. comm., 

2002; WDFW, M. Downen, pers. comm., 2004). The remaining 29 lakes are 

currently fishless, and any residual adverse impacts from past stocking would be 

considered negligible. 

Impairment of native fish species across the study area would not occur under 

alternative A. 

Impacts of Current Lake 

Treatment Methods on Aquatic Organisms 

No lake treatments occur under alternative A; therefore, there would be no 

impacts on aquatic organisms from lake treatment methods. 

Cumulative Impacts 

No projects are proposed or in planning stages that would change the road access 

to any unit of the North Cascades Complex, and no new major trails or trailheads 

are being considered. Flooding in recent years has limited some access to certain 

lakes, and this would result in a short-term reduction of activity around certain 

lakes, including fishing. No new resorts or major upgrades of existing facilities 

are known. Overall, visitor use is expected to follow about the same patterns that 

it has for several years, resulting in the same level of fishing pressure on most 

lakes and connected streams. This use of the lakes and surrounding drainages 

would contribute negligible to minor adverse impacts on the plankton, 

macroinvertebrates, amphibians, and native fish that may inhabit the shallow 

riparian areas that visitors use to cross and enter the waters for fishing. This 

causes very limited compaction of shorelines and sedimentation of the waters 

where these animals breed, feed, and hide from other predators, with resultant 

negligible to minor impacts. 

Mountain lake fisheries on National Forest System lands that surround the North 

Cascades Complex are also managed by the WDFW. The department’s 

management approach (described in WDFW [2001]) is expected to be similar in 

the foreseeable future to what is currently being done. No lakes or streams inside 

the North Cascades Complex boundaries are directly downstream from an 

outside lake with reproducing fish, so no impacts would be expected in the study 

area from outside fishery management actions. 

There would be continued, localized, and sporadic effects on native fish and 

other aquatic organisms from logging and dams and reservoir construction that 

have occurred and continue to occur outside the North Cascades Complex, 

including adjacent watersheds. These actions cause nonpoint pollution (primarily 

runoff of disturbed or exposed soils) that would adversely affect water quality by 

decreasing oxygen levels, increasing temperatures, and creating sedimentation 

that can cover spawning habitat. Impact levels on aquatic organisms in the North 

Cascades Complex or in downstream drainages would vary, depending on the 
E NVIRONMENTAL C ONSEQUENCES

260 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

location of the projects and the species present. Pre-construction surveys and 

mitigation measures are usually required to minimize effects on native species, 

especially any protected species, so most impacts on aquatic organisms in the 

study area from these actions would be negligible to minor. Even with mitigation, 

various levels of adverse impacts on species have occurred and may continue. 

Other sources of impacts continue to occur that may affect the health and 

viability of native aquatic organisms. In some lakes in the North Cascades 

Complex, persistent organic pollutants (POP) and methyl-mercury have been 

found that appear to result from airborne pollutants being deposited on snow and 

washed into lakes. There may be an additional source of airborne pollution from 

the Darrington Power Plant, which, if approved, would operate about 20 miles 

southwest of the North Cascades Complex. Plant operation could potentially 

increase regional acid deposition, thereby increasing lake acidity and metal 

availability. Some of these pollutants might bioaccumulate to higher 

concentrations in the top predators in a system, such as salamanders in a lake, to 

the point where the pollutants would cause species to be less viable. If that 

occurred, then the cumulative impacts of pollutants and other impacts, perhaps 

from fish, might eliminate that predator species from certain lakes or even cause 

a more general decline in the population. Future monitoring may help to 

determine if bioaccumulation of persistent organic pollutants or methyl-mercury 

were occurring in high mountain lakes. Also, there is some concern that diseases 

or water mold may be spread by stocking affected fish; however, there is no 

evidence that this has occurred, and the water mold, Saprolegnia, is already 

present in the natural environment (WDFW 2001). In addition, hatcheries used 

by the WDFW are very cautious about eliminating the risk of disease or mold in 

their stocks, so the threat of impacts from mold or disease is considered 

negligible. 

Overall, the cumulative impacts associated with other actions in the area, added 

to the impacts predicted under alternative A, would result in short- and long-term 

minor to potentially major adverse impacts on plankton, macroinvertebrates, 

amphibians, and/or certain species of native fish in individual lakes in the study 

area but with overall minor to moderate impacts for the region. 

Conclusion 

Table 32 summarizes the direct impacts expected, by numbers of lakes, for 

plankton, macroinvertebrates, amphibians, and native fish. 

Aquatic organisms (including plankton, macroinvertebrates, and amphibians) 

would continue to experience long-term negligible to minor adverse impacts 

from fish predation and competition in lakes stocked with low densities of 

nonreproducing fish. 

In lakes with high densities of reproducing fish, certain plankton and 

macroinvertebrates would continue to experience long-term moderate to major 

adverse impacts from intensive predation and competition. Long-term minor to 

moderate, adverse impacts on amphibians would continue in lakes with 

reproducing populations of fish, limited refugia, relatively high nutrient (for 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 261

example, high total Kjeldahl nitrogen) availability, and limited lake connectivity 

to other water bodies with suitable amphibian habitat. 

Long-term moderate to major adverse impacts from hybridization between native 

and nonnative fish would continue to persist. 

Short- and long-term adverse cumulative impacts on aquatic organisms would 

vary widely depending upon trends in aquatic ecosystem stressors such as air 

pollution, development in surrounding watersheds, and climate change. Overall, 

the cumulative impacts associated with other actions in the area, added to the 

impacts predicted under alternative A, would result in short- and long-term minor 

to potentially major adverse impacts on plankton, macroinvertebrates, and 

amphibians, and/or certain species of native fish in individual lakes in the study 

area but with overall minor to moderate adverse impacts for the region. 

Impairment of aquatic organisms across the study area would not occur under 

alternative A. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative would be to eliminate or reduce numbers of 

reproducing fish from lakes in the study area. Restocking of nonreproducing fish 

would be allowed only where biological resources would be protected. Based on 

best available science, some lakes would be restocked with nonreproducing fish 

at low densities once reproducing fish have been removed. Lakes where 

information needed to make these decisions is missing would not be stocked until 

that information becomes available, as discussed in the monitoring program and 

associated adaptive management approach described in appendix F. This 

extensive monitoring program would be implemented in order to adjust 

management in the future to avoid unacceptable effects on native biota from fish 

presence. 

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed Fish 

Stocking on Aquatic Organisms 

Plankton. Under alternative B, adverse impacts in 14 lakes would gradually be 

reduced over time from major or moderate levels to minor levels, since all lakes 

that previously had very high or high densities of fish would have the densities 

reduced or fish eliminated, and fish density is a key factor affecting plankton in 

high mountain lakes. Overall, 29 of the 91 lakes would be expected to experience 

minor long-term adverse impacts as low-density fish populations are created or 

retained through various methods. Long-term direct and indirect impacts on the 

plankton community would continue to occur for the foreseeable future. Direct 
E NVIRONMENTAL C ONSEQUENCES

262 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

impacts would include predation and competition for prey; indirect impacts 

would include changes in nutrient cycling and food web dynamics. 

In 62 other lakes, impacts on plankton would be considered negligible. In 13 of 

these lakes, fish would be removed or no longer stocked, and the lakes would be 

evaluated to determine if stocking at low densities would be resumed. Over the 

long term, adverse impacts on plankton would be reduced to negligible levels, 

which would increase to minor levels if fish stocking were resumed. In 20 of the 

62 lakes, removal or discontinued stocking of fish would be permanent and occur 

over time. Adverse impacts would be gradually reduced to negligible levels, with 

the expected recovery of plankton populations and community structure to 

conditions comparable to those in historically stocked but currently fishless 

lakes. Beneficial effects would result from the removal of fish and the long-term 

recovery of the plankton community. The remaining 29 lakes with negligible 

impacts are those that were historically stocked but are currently fishless and 

would remain fishless. Plankton abundance and community structure in these 

lakes would primarily be influenced by biogeographical evolutionary processes. 

Impairment of plankton species across the study area would not occur under 

alternative B. 

Macroinvertebrates. Under alternative B, high-density fish populations would 

gradually be reduced or eliminated, which would eventually eliminate all major 

and moderate adverse impacts on macroinvertebrates throughout the North 

Cascades Complex. Low-density fish populations would be retained in 29 of the 

91 lakes by either stocking with nonreproducing fish, reducing the density of 

existing fish populations, or supplementing low-density reproducing fish by 

stocking some nonreproducing fish. In these 29 lakes, long-term direct and 

indirect impacts on the macroinvertebrate community would continue to occur 

for the foreseeable future. Direct and indirect impacts would be the same as 

described for alternative A and would include predation and competition for prey 

and changes in nutrient cycling and food web dynamics. These impacts would be 

adverse, minor, and long term. 

In 62 of the 91 lakes, adverse impacts on macroinvertebrates would be 

considered negligible. Thirteen of these lakes would be further evaluated prior to 

determining management actions. Existing low-density reproducing or stocked 

populations would be removed, and the response of native biota in these lakes, 

including macroinvertebrates, would be monitored. Low-density nonreproducing 

fish would be stocked only if monitoring results indicate it is appropriate. 

Macroinvertebrate populations and community structure would be expected to 

recover to levels comparable to those in currently fishless but otherwise similar 

lakes. Initial direct and indirect impacts would be negligible, although stocking 

of low-density nonreproducing fish in these lakes would result in minor impacts. 

In 20 of the 62 lakes, removal or discontinued stocking of fish would occur over 

time, and impacts would gradually be reduced to negligible levels with the 

expected recovery of macroinvertebrate populations and community structure to 

conditions comparable to those in historically stocked but currently fishless 

lakes. Beneficial effects would result from fish removal and by providing for the 

long-term recovery of macroinvertebrate populations and community structure. 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 263

The remaining 29 lakes are those that were historically stocked but are currently 

fishless and would remain fishless. Macroinvertebrate abundance and community 

structure in these lakes would primarily be influenced by biogeographical and 

evolutionary processes, with negligible residual adverse impacts. 

Impairment of macroinvertebrate species across the study area would not occur 

under alternative B. 

Amphibians. Under alternative B, the eventual reduction of fish density would 

gradually eliminate major and moderate impacts on amphibians over time. In 9 of 

the 91 lakes, impacts on amphibians would be expected to be minor. Three of the 

9 lakes are within the range of Northwestern salamanders, but have low densities 

of trout. Six of the lakes are within the range of long-toed salamanders but have 

low densities of trout with low IOC (Index of Connectivity) values, causing the 

impacts to be on a minor level. Two of these 6 lakes do not have recorded values 

for TKN and have been assigned a minor impact based on the possibility of high 

TKN values. If subsequent research shows that TKN values in these lakes are 

low, the level of impacts would be reduced. In very general terms, impacts would 

be high if TKN levels are high, the IOC is low, and densities of fish in a lake are 

high. If, for instance, densities of fish are low or IOC is particularly high for a 

lake or if TKN level are low, the impact would be reduced. For a more detailed 

discussion of how impact levels were derived, see appendix G. 

In 82 of the 91 lakes, impacts on amphibians would be negligible. Twenty-nine 

lakes would remain fishless, with negligible residual adverse impacts. Of the 53 

remaining lakes, 20 are either outside the distribution of salamanders or do not 

have suitable aquatic or terrestrial habitat for long-toed or Northwestern 

salamanders. The remaining 33 lakes are within either the range of long-toed 

salamanders or the range of Northwestern salamanders. Adverse impacts on 

salamanders in these 33 lakes would gradually be reduced to negligible levels as 

the lakes either become fishless or have low densities of trout with high IOC 

values. For those 13 lakes that would undergo further evaluation, impacts would 

increase if stocking were resumed in the future. 

Impairment of amphibian species across the study area would not occur under 

alternative B. 

Native Fish. The extent of impacts on downstream native fish communities 

under alternative B would be reduced compared to alternative A, with the 

eventual elimination of the one major and nine moderate impacts identified in 

alternative A. 

In 7 lakes, long-term impacts would be minor because high-density populations 

of nonnative brook and rainbow trout would be eliminated from high mountain 

lakes in the study area. However, there would still be reproducing rainbow trout 

or cutthroat trout not native to the basin in a west-side lake (e.g., westslope 

cutthroat in a west-side lake) or, an east-side Mt. Whitney rainbow trout in an 

east-side lake. The presence of these nonnative fish would result in some 

competition, predation, and possible interbreeding with native species, but 

because of the greatly reduced densities that would remain in the lakes, it is 

unlikely that a large number of fish would escape to downstream waters. In the 
E NVIRONMENTAL C ONSEQUENCES

264 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

case of the Mt. Whitney rainbow, there are no native rainbows present on the east 

side, and therefore, there is some concern about the potential for hybridization. 

In 84 lakes, long-term adverse impacts on native fish would be 

negligible. In 55 of these lakes, high densities of fish would be 

removed and either not restocked or restricted to low-density 

nonreproducing trout. Impacts on downstream native fish 

communities from reproducing populations of fish would gradually 

be reduced to negligible levels because nonreproducing fish would 

be the only fish stocked in any of the lakes after removal of the present 

populations. In other lakes with negligible impacts, any reproducing trout 

remaining would be incapable of establishing reproducing populations in outlet 

streams or hybridizing with native populations of fish, similar to alternative A, or 

there is no connecting outlet to downstream basins. Finally, 29 of the 84 lakes are 

fishless and would remain fishless, with residual negligible impacts on 

downstream native fish. Overall, the reduction in density and/or elimination of 

fish would yield a long-term beneficial effect to downstream native fish. 

Impairment of native fish species across the study area would not occur under 

alternative B. 

Impacts of Proposed Lake 

Treatment Methods on Aquatic Organisms 

The lake treatment methods that are proposed in this plan/EIS are discussed in 

detail in the “Alternatives” chapter. 

The method proposed for use in each lake was selected based on the type of fish 

population present and the physical characteristics of the lake environment. The 

proposed methods have a range of potential adverse impacts on aquatic 

organisms, depending on the methods and aquatic resource category considered. 

Natural Methods. Under alternative B, natural methods would be used at 

12 lakes. The use of natural methods means discontinuing all stocking and 

allowing the remaining nonreproducing fish to gradually die out and/or be 

eliminated through fishing. This approach is effective only in lakes without 

extensive natural reproduction. Because natural removal methods involve no 

direct actions within each lake, very limited human presence, and no mechanized 

transport (such as helicopters), these methods would result in effectively no or 

negligible adverse impacts on any group of aquatic organisms. 

Mechanical Methods. Mechanical removal methods involve two different 

approaches: (1) the use of gillnets, fyke nets, or hook and line to remove fish, 

possibly combined with electrofishing and/or trapping; and (2) physical 

exclusion of fish from their spawning habitat. In the case of gillnetting, 

helicopters would be used to transport equipment to the site. The use of nets and 

traps is proposed for 8 lakes. This method has effectively no potential for direct 

or indirect impacts on plankton; therefore, impacts on plankton from this removal 

method are considered negligible. There is some risk of impacts on 

macroinvertebrate species from trampling or other sources of mechanical injury, 

but the extent of these potential impacts is considered to be minor. Amphibians 

face some risk of direct impacts from trampling, or possibly from electroshocks 

Brook trout, a 

nonnative fish, are 

especially aggressive 

and can compete with 

native trout for

available resources.
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 265

if they are in the immediate vicinity of the apparatus while it is being operated. 

Amphibian adults, which may not survive prolonged submersion, may be 

captured in traps or entangled in nets; however, the number of individuals 

potentially impacted would be small, and nets and traps would be inspected daily 

to reduce or eliminate nontarget organism mortality. Therefore, impacts on 

amphibian populations would be short term and minor. There is effectively no 

potential for impacts on native fish in downstream drainages; therefore, the 

extent of impacts on native fish is considered negligible. All impacts resulting 

from use of nets or traps would be of short-term duration, and no impacts relating 

to noise from the short-term presence of a helicopter over the site would be 

expected to affect any aquatic species. 

The spawning habitat exclusion treatment method involves blocking access to the 

tributary spawning areas of mountain lakes by “cobbling over” gravel beds in the 

inlet or outlet tributaries to the lake, which creates a barrier to the spawning 

habitat. This method is proposed for only one lake: Wilcox/Lillie, Upper. 

Because these actions would not take place in the subject lake, and would not 

result in any appreciable changes in lake characteristics, this approach poses 

essentially no risk of adverse direct impacts on plankton and native fish. Physical 

modification of tributary areas presents some risk of direct impacts on 

macroinvertebrates and amphibians in these areas, but impacts would be minor 

and short term. 

Chemical Method. The chemical method is proposed for use in 19 lakes under 

alternative B. This involves the use of the piscicide antimycin to kill fish 

populations (refer to the “Alternatives” chapter for details about this chemical 

and its mode of action). The chemical method would be proposed for large lakes 

with reproducing fish populations where mechanical removal methods would not 

be practical. Antimycin was selected for use over other piscicides because it is 

effective at relatively low concentrations, degrades rapidly, does not repel target 

fish, and has been shown to have only relatively minor and/or short-term impacts 

on nontarget organisms. Effects of antimycin on plankton and invertebrates vary 

depending on concentration levels and on the type of organism, as evidenced by 

numerous studies. Rabe and Wissmar (1969) observed a reduction in 

zooplankton abundance following antimycin application in an alpine lake 

environment, but this effect was short term. Controlled applications of antimycin 

in experimental ponds (generally applied at typical concentrations for fish 

control) resulted in no observable effects on any species of macrobenthos (Houf 

and Campbell 1977). However, antimycin treatments at higher concentrations 

have been observed to result in macroinvertebrate mortality in stream 

environments, with these effects being of short-term duration (Jacobi and Degan 

1977; Morrison 1987). Furthermore, a recent report written by Finlayson et. al. 

(2001) states that the toxicity of antimycin to aquatic invertebrates has been 

found to be similar to that of fish at concentrations comparable to those that 

would be used in lakes in the North Cascades Complex study area. Some taxa, 

such as water fleas, copepods, amphipods, stoneflies, and caddisflies, are 

reportedly more sensitive to antimycin; while stoneflies, dragonflies, annelid 

worms, and water bugs appear to more resistant (Schnick 1974). Field tests of 

antimycin effects have shown no observable impacts on various amphibian 

species at typical fish-control treatment levels. 

Benthos: Organisms 

that live in or on the 

bottom in aquatic 

habitats (the benthic 

zone). 

“Macrobenthos” 

includes all 

invertebrates that 

are found in the 

benthos; they are 

typically larger than 

one millimeter. 
E NVIRONMENTAL C ONSEQUENCES

266 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Antimycin has little potential for adverse impacts on downstream fish 

populations if application is effectively controlled. It degrades rapidly in 

turbulent water, losing its effectiveness after an elevational drop of 200 to 

300 feet (Tiffan and Bergersen 1996). The distance and elevation drop separating 

high mountain lakes from native fish populations would create an effective 

separation from the treated environment. To ensure complete protection of 

downstream fish populations, antimycin applications would be neutralized at the 

lake outlet by adding small amounts of potassium permanganate, which is an 

oxidizer with no adverse impacts on water quality or nontarget organisms 

(Morrison 1987). 

Based on the available literature, the potential impacts of chemical fish treatment 

on plankton, macroinvertebrates, and amphibian populations and communities in 

19 lakes would be direct, short term, and minor. Potential direct and indirect 

impacts on native fish would be negligible. 

Antimycin use would result in moderate, direct, short-term impacts (of one to 

several years’ duration) to sensitive plankton and macroinvertebrates, since it 

would be expected to cause an initial die-off and/or reduction in density to 

sensitive species in the treatment area. However, sensitive taxa would be 

expected to recover (in terms of their previous abundance and diversity) within 

one to several years after treatment. Over the long term, taxa would indirectly 

benefit from the removal of fish predation. Impacts on amphibian populations 

and communities would be direct, short-term, and minor. Potential direct and 

indirect impacts on downstream native fish would be negligible. 

Cumulative Impacts 

Cumulative impacts under alternative B would be similar to those described 

under alternative A, but slightly reduced due to the eventual elimination of 

impacts in those lakes and connected watersheds where nonnative fish would be 

eliminated, resulting in 49 fishless lakes (compared to 29 fishless lakes under 

alternative A). 

No lakes or streams inside the North Cascades Complex boundaries are directly 

downstream from an outside lake with reproducing fish, so no impacts would be 

expected in the study area from outside fishery management actions. 

Overall, the impacts associated with other actions in the region, added to the 

residual impacts predicted under alternative B, would have minor to moderate 

adverse impacts on all groups of aquatic organisms on both an individual lake 

and regional basis. 

Conclusion 

Table 32 summarizes the direct impacts expected, by numbers of lakes, for 

plankton, macroinvertebrates, amphibians, and native fish. 

Aquatic organisms (including plankton, macroinvertebrates, and amphibians) 

would continue to experience long-term negligible to minor adverse impacts 

from fish predation and competition in lakes that would continue to be stocked 

with low densities of nonreproducing fish. These impacts would decline further 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 267

in the future as stocking is curtailed or eliminated in lakes based on adaptive 

management decisions pertaining to stocking. 

Removal of reproducing populations of fish from select lakes would eventually 

result in long-term beneficial effects on aquatic organisms in those lakes; 

however, removal of reproducing fish populations would take many years. Until 

fish are removed, minor to major impacts on aquatic organisms would persist as 

described in alternative A. 

Mechanical methods of fish removal (netting, trapping, spawning habitat 

exclusion) would have short-term negligible to minor adverse impacts on aquatic 

organisms. Chemical methods of fish removal (application of the piscicide 

antimycin) would have short-term negligible to moderate adverse impacts on 

certain aquatic organisms. 

Long-term minor to moderate adverse impacts on native fish would continue to 

be primarily associated with hybridization between native and nonnative fish. 

The risk of hybridization would decline over the long term as reproducing 

populations of fish were removed and fewer nonnative fish dispersed 

downstream from lakes. The risk of hybridization, however, would not be 

entirely eliminated primarily because reproducing populations of nonnative fish 

are now present in many drainages throughout the North Cascades Complex. 

Compared to alternative A, there would be a long-term beneficial cumulative 

impact on native aquatic organisms because a minimum of 20 lakes would 

eventually become fishless. Short- and long-term adverse cumulative impacts on 

aquatic organisms from threats other than nonnative fish would vary widely 

depending upon trends in aquatic ecosystem stressors such as air pollution, 

development in surrounding watersheds, and climate change. 

Impairment of aquatic organisms across the study area would not occur under 

alternative B. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Under alternative C, 9 lakes in Ross Lake and Lake Chelan National Recreation 

Areas would have fish and 2 lakes would be evaluated for restocking. Eleven 

other lakes in the national recreation areas would remain fishless or be returned 

to fishless conditions. The remaining 69 lakes (which are in the national park) 

would be returned to their natural fishless conditions or would remain fishless. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 
E NVIRONMENTAL C ONSEQUENCES

268 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Under alternative B, a management action code of 

“2B” would be applied to the six lakes pictured 

above, in addition to Blum (Largest/Middle, No. 3) 

and Dee Dee, Upper. 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 269

Impacts of Proposed 

Fish Stocking on Aquatic Organisms 

Plankton. Under alternative C, more lakes would be treated over time to remove 

fish, so impact levels would gradually be reduced in more lakes in the study area, 

compared to alternative A. At the completion of all lake treatments, minor 

impacts would occur in 9 lakes, where low-density fish populations would be 

retained by either replacing high densities of fish with lower densities, or 

continuing to stock with low densities of nonreproducing fish. In these lakes, 

adverse impacts on the plankton community would be long term and minor. 

Direct and indirect impacts would be of the same type as described under 

alternative A and would include predation and competition for prey and changes 

in nutrient cycling and food web dynamics. 

Two of the 91 lakes would be further evaluated prior to determining management 

actions. In these lakes, existing low-density reproducing or stocked populations 

would be removed, and the response of native biota, including plankton, would 

be monitored. Low-density nonreproducing fish would be stocked only if results 

of monitoring indicate it would be appropriate. Plankton populations and 

community structure would be expected to recover to levels comparable to those 

in currently fishless but otherwise similar lakes. Initial direct and indirect impacts 

would be negligible, although restocking the lakes with low-density 

nonreproducing fish would be expected to result in minor impacts. 

In 51 of the 91 lakes, existing low-density reproducing or stocked populations of 

introduced fish would be removed. Plankton populations and community 

structure would be expected to recover to levels comparable to those in 

historically stocked but currently fishless lakes that are otherwise similar. Minor 

impacts would be reduced to negligible over time. Residual long-term adverse 

impacts would be considered negligible, and long-term beneficial effects would 

result. 

Under alternative C, the 29 historically stocked but currently fishless lakes would 

remain fishless. Plankton abundance and community structure in these lakes 

would primarily be influenced by biogeographical and evolutionary processes, as 

described for alternative A, with residual adverse negligible impacts. 

Impairment of plankton species across the study area would not occur under 

alternative C.

Macroinvertebrates. Under alternative C, more lakes would be treated over time 

to remove fish, so impact levels would gradually be reduced in more lakes in the 

study area. Minor impacts would occur in 9 lakes, where low-density fish 

populations would be retained by either replacing high densities of fish with 

lower densities, or continuing to stock with low densities of nonreproducing fish. 

In these lakes, the impacts on macroinvertebrates would be minor and long term. 

Direct and indirect impacts would be the same as those described under 

alternative A (those impacts are predation and competition for prey and changes 

in nutrient cycling and food web dynamics). 

In two other lakes, further evaluation would be completed prior to determining 

management actions. In these lakes, the existing low-density reproducing or 
E NVIRONMENTAL C ONSEQUENCES

270 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Northwestern

salamander

stocked populations would be removed, and the response of native biota, 

including macroinvertebrates, would be monitored. Low-density stocked 

populations would be reintroduced only if monitoring results indicate it is 

appropriate. Macroinvertebrate populations and community structure would be 

expected to recover to levels comparable to those in currently fishless but 

otherwise similar lakes. Direct and indirect impacts would be negligible. 

Restocking of low-density nonreproducing fish in these lakes would be expected 

to result in minor impacts. 

In 51 lakes, removal or discontinuation of fish stocking would allow for the 

expected gradual recovery of macroinvertebrate populations and community 

structure to conditions comparable to those in historically stocked but currently 

fishless lakes. Minor impacts would gradually be reduced to long-term negligible 

impact levels, and long-term beneficial effects would result. 

Under alternative C, 29 historically stocked but currently fishless lakes would 

remain fishless. Macroinvertebrate abundance and community structure in these 

lakes would primarily be influenced by biogeographical or evolutionary 

processes, as described for alternative A, with negligible residual adverse 

impacts. 

Impairment of macroinvertebrate species across the study area would not occur 

under alternative C. 

Amphibians. Under alternative C, no lakes would experience major or moderate 

impacts on amphibians, and more lakes would have impacts gradually reduced 

from minor to negligible levels because more lakes would either become fishless 

or be reduced to low fish densities. 

In five lakes, adverse impacts on amphibians are predicted to be minor. Three of 

these lakes are within the range of Northwestern salamanders but have low 

densities of trout. Two of these lakes are within the range of long-toed 

salamanders but have low densities of trout with low IOC (Index of 

Connectivity) values, which indicate minor impact levels. 

In 86 of the 91 lakes, impacts on amphibians would be considered negligible. 

Twenty-nine lakes would continue to remain fishless, with negligible residual 

adverse impacts. Of the 57 remaining lakes, 20 are either outside the range of 

salamanders or do not have suitable aquatic or terrestrial habitat for long-toed or 

Northwestern salamanders. Thirty-four of these lakes are within the range of 

long-toed salamanders, and 3 are within the range of the Northwestern 

salamander. Impacts on salamanders in these 37 lakes would gradually be 

reduced to negligible levels because the lakes have either become fishless or have 

low densities of trout with high IOC values. For a more detailed discussion of 

how impact levels were derived, see appendix G. 

Impairment of amphibian species across the study area would not occur under 

alternative C. 

Native Fish. Under alternative C, the potential for adverse impacts on 

downstream native fish would be substantially reduced over time, compared to 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 271

alternative A, with no major or moderate adverse impacts. Only one lake, 

Unnamed MR-16-01, would continue to have minor impacts on downstream 

native fish. In Unnamed MR-16-01, a low-density population of reproducing 

cutthroat trout would continue to remain in a west-side lake, which would pose a 

minor threat to downstream native fish through competition. The reproductive 

status of the trout would need to be evaluated to determine if a minor impact 

actually exists. 

In 90 lakes, long-term impacts on native fish would be negligible. In some of 

these lakes, fish would be removed and either not restocked or restocked with 

low densities of nonreproducing trout. Impacts on downstream native fish from 

stocked fish would eventually become negligible because nonreproducing fish 

would be the only fish stocked in any of the lakes after removal of the present 

populations. In other lakes with negligible impacts, any reproducing trout 

remaining would be incapable of establishing reproducing populations in outlet 

streams or hybridizing with native fish, similar to alternative A, or there is no 

connection to downstream basins. The 29 currently fishless lakes would remain 

fishless, with residual negligible adverse impacts. Overall, the widespread 

reduction in fish densities and/or elimination of fish under alternative C would be 

a long-term benefit to downstream native fish. 

Impairment of native fish species across the study area would not occur under 

alternative C. 

Impacts of Proposed Lake 

Treatment Methods on Aquatic Organisms 

Under alternative C, the types of impacts associated with the various lake 

treatment methods would be the same as described for alternative B; however, 

the number of lakes affected by those treatments would vary, and more lakes 

would experience impacts (albeit minor and short term) from chemical and 

mechanical treatments to remove fish. 

Natural Methods. Under alternative C, 21 lakes would be subject to natural fish 

removal methods, which means stocking would be discontinued; this is 9 more 

lakes than alternative B. There would be few, if any, impacts on any aquatic 

organisms from this type of treatment, which involves natural die-out and 

removal by fishing, so impacts would remain about the same – negligible and 

short term. 

Mechanical Methods. There would be 10 lakes slated for mechanical treatment, 

an increase of only 2 lakes over alternative B. Impacts on macroinvertebrates and 

amphibians would be short term and minor, and impacts on native fish and 

plankton would be negligible for all aspects of this treatment. Overall, impacts 

would be about the same as for alternative B. 

Chemical Method. For chemical treatment, the number of lakes treated would 

increase to 25. Impacts on sensitive plankton and macroinvertebrates from the 

use of antimycin would be moderate, direct, and short term due to the expected 

die-off of certain sensitive species in the vicinity of the treatment. Impacts on 

sensitive taxa would be expected to return to their previous abundance and 
E NVIRONMENTAL C ONSEQUENCES

272 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

diversity within one to several years after treatment. Over the long term, taxa 

would indirectly benefit from the removal of fish predation. Impacts on 

amphibian populations and communities would be direct, short term, and minor. 

Potential direct and indirect impacts on downstream native fish would be 

negligible. Six more lakes would be treated in this manner compared to 

alternative B, but the overall increase in impact intensity would be minor because 

adverse impacts from the use of antimycin are so limited. 

Cumulative Impacts 

Cumulative impacts under alternative C would be similar to those described 

under alternative A but reduced due to the elimination of impacts in those lakes 

and connected watersheds where high-density populations of fish would be 

eliminated, resulting in up to 80 fishless lakes (compared to 29 fishless lakes 

under alternative A). There would be reduced fishing pressure on the lakes and 

connected streams in the North Cascades Complex. Anglers would be displaced 

to surrounding lakes, and there would be negligible to minor impacts on aquatic 

organisms from visitors crossing and entering the waters for fishing. 

No lakes or streams inside the North Cascades Complex boundaries are directly 

downstream from an outside lake with reproducing fish, so no impacts would be 

expected in the study area from outside fishery management actions. 

Overall, the impacts associated with other actions in the region, added to the 

residual impacts predicted under alternative C, would have minor to moderate 

adverse impacts on all groups of aquatic organisms, both at an individual lake 

and in the region. 

Conclusion 

Table 32 summarizes the direct impacts expected, by numbers of lakes, for 

plankton, macroinvertebrates, amphibians, and native fish. 

Aquatic organisms (including plankton, macroinvertebrates, and amphibians) 

would continue to experience long-term negligible to minor adverse impacts 

from fish predation and competition in national recreation area lakes that would 

continue to be stocked with low densities of nonreproducing fish. These impacts 

could decline further in the future as stocking is curtailed or eliminated in lakes 

based on adaptive management decisions pertaining to stocking. 

Removal of reproducing populations of fish from lakes in the national park 

portion of the North Cascades Complex would eventually result in long-term 

beneficial effects on aquatic organisms in those lakes where removal proved 

feasible; however, removal of reproducing fish populations from the entire 

national park unit and select lakes in the national recreation areas would take 

many years. Until fish are removed, minor to major impacts on aquatic organisms 

would persist as described in alternative A. 

Mechanical methods of fish removal (netting, trapping, spawning habitat 

exclusion) would have short-term negligible to minor adverse impacts on aquatic 

organisms. Chemical methods of fish removal (application of the piscicide 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 273

antimycin) would have short-term negligible to moderate adverse impacts on 

certain aquatic organisms. 

Long-term minor to moderate adverse impacts on native fish would continue to 

be associated with hybridization between native and nonnative fish. The risk of 

hybridization would decline over the long term as reproducing populations of 

fish are removed and fewer nonnative fish dispersed downstream from lakes. The 

risk of hybridization, however, would not be entirely eliminated primarily 

because nonnative fish are now present in many drainages throughout the North 

Cascades Complex. 

Compared to alternative A, there would be a long-term beneficial cumulative 

impact on populations of native aquatic organisms because a minimum of 

51 lakes (all lakes in the national park unit and select national recreation area 

lakes) would eventually become fishless. Short- and long-term adverse 

cumulative impacts on aquatic organisms from threats other than nonnative fish 

would vary widely depending upon trends in aquatic ecosystem stressors such as 

air pollution, development in surrounding watersheds, and climate change. 

Impairment of aquatic organisms across the study area would not occur under 

alternative C. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS

Under alternative D, the goal would be to remove fish from all 91 lakes in the 

study area. All 91 lakes would eventually be unavailable for fishing, with some 

fish remaining in certain lakes as management actions are implemented over 

time. 

The “Alternatives” chapter provides a detailed description of alternative D. For 

more information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed Fish 

Stocking on Aquatic Organisms 

Plankton. In the 62 fish-bearing lakes where fish populations would be removed 

or allowed to die out, the plankton community would generally be expected to 

recover over the years to conditions comparable to those in historically fishbearing but currently fishless lakes, with resultant negligible impacts. Since lakes 

would be treated over time, some minor to moderate impacts would continue 

until all high-density populations of nonnative fish were removed. Upon removal, 

the phytoplankton community structure that would develop in each lake may be 

different from what was historically present before fish stocking, but all species 

would most likely be present, based on studies completed to date (Drake and 

Naiman 2000). 

Research has shown that, in many cases, zooplankton that have been adversely 

impacted can recover after fish are removed (Parker et al. 2001), and zooplankton 
E NVIRONMENTAL C ONSEQUENCES

274 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

species can be effectively reintroduced to lakes through managed introductions 

(McNaught et al. 1999; Parker et al. 2001). Therefore, it is expected that most 

zooplankton species would eventually recover to abundance comparable to 

historic levels, unless the population has been completely extirpated by 

predation, and that extirpated species would be reintroduced from adjacent lakes 

if desired. Using such approaches, the zooplankton community structure would 

be rehabilitated to levels comparable to those in fishless but otherwise similar 

lakes. Long-term effects of fish removal would be expected to be beneficial, with 

larger changes occurring in lakes that currently have high-density fish 

populations. 

Twenty-nine lakes were historically stocked with trout but are currently fishless. 

Observed plankton community structure and abundance in these lakes is 

generally comparable to those in similar fishless lakes. Plankton populations in 

these lakes would be influenced mainly by biogeographical or evolutionary 

processes. Residual adverse impacts of fish stocking in these lakes would be 

considered negligible after recovery has occurred. These lakes serve as a 

benchmark for expected conditions in lakes following a period recovery after fish 

are removed. 

Impairment of plankton species across the study area would not occur under 

alternative D. 

Macroinvertebrates. Removal of fish from 62 lakes would eventually result in 

the expected recovery of the macroinvertebrate community to levels comparable 

to those in historically stocked but currently fishless lakes. Macroinvertebrate 

species in individual lakes that have been extirpated by predation would be 

expected to recolonize from adjacent areas within several years, depending on 

species and proximity of other breeding areas. Research indicates that effects on 

macroinvertebrates are often limited to the segments of the population exposed to 

fish predation and that, while some population segments may be depressed or 

even temporarily eliminated, these species usually have a high dispersal potential 

and recolonize relatively quickly (Bilton et al. 2001; Bohonak and Jenkins 2003). 

Species would also be reintroduced through management intervention if desired. 

Residual adverse impacts in all 62 lakes would be negligible and long term, with 

some minor to possibly major impacts remaining for several years until all lakes 

with high densities of fish are treated. The eventual removal of fish would result 

in long-term beneficial effects in all these lakes, with the greater benefits 

occurring in lakes that currently have higher fish densities. 

Twenty-nine lakes were historically stocked with trout but currently have no fish 

populations. Observed macroinvertebrate community structure and abundance in 

these lakes is generally comparable to those in similar fishless lakes. 

Macroinvertebrate populations in these lakes would be influenced mainly by 

biogeographical or evolutionary processes. Residual adverse impacts of fish 

stocking in these lakes would be considered negligible after recovery has 

occurred. These lakes would serve as a benchmark for expected conditions in 

lakes following a period of recovery after fish are removed. 

Impairment of macroinvertebrate species across the study area would not occur 

under alternative D. 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 275

Amphibians. Under alternative D, fish would gradually be removed from 

62 lakes, resulting in long-term residual adverse impacts on amphibian 

communities from fish populations, but at a negligible level. Until all highdensity populations are removed, some minor to major impacts would continue. 

Long-term effects of fish removal would be beneficial. In the absence of fish 

predation, terrestrial amphibian adults, surviving larvae, or neotenic adults would 

be expected to re-establish populations in a lake. 

Impairment of amphibian species across the study area would not occur under 

alternative D. 

Native Fish. Under alternative D, fish would eventually be removed from 

62 lakes (or allowed to disappear through natural mortality or not being 

restocked), resulting in a reduction of impacts on downstream native fish 

communities to negligible levels over time. Some minor to moderate adverse 

impacts may continue for several years as management actions are implemented. 

The long-term effects of fish removal would be beneficial. 

Impairment of native fish species across the study area would not occur under 

alternative D. 

Impacts of Proposed Lake 

Treatment Methods on Aquatic Organisms 

For alternative D, the types of impacts associated with the various lake treatment 

methods would be the same as described under alternative B; however, the 

numbers of lakes affected by those treatments would vary, and more lakes would 

experience impacts (albeit minor and short term) from chemical and mechanical 

treatments to remove fish. 

Natural Methods. Under alternative D, 26 lakes would be subject to natural 

removal methods where stocking would be discontinued. This is 14 more lakes 

than alternative B and 5 more than alternative C. However, since there are few, if 

any, impacts on aquatic organisms from this type of removal, overall impacts 

would remain about the same – short term and negligible. 

Mechanical Methods. There would be 11 lakes slated for mechanical treatment 

under alternative D, an increase of only 1 lake over alternative C and 3 lakes 

more than alternative B. Again, with minimal adverse impacts expected, impact 

levels would remain short term and minor for amphibians and macroinvertebrates 

and negligible for native fish and plankton. 

Chemical Method. The same number of lakes (25) would be chemically treated 

under alternative D as under alternative C. Impacts on plankton and 

macroinvertebrates from the use of antimycin would be moderate, direct, and 

short term due to the expected die-off of certain sensitive species in the vicinity 

of the treatment. The sensitive taxa would be expected to return to their previous 

abundance and diversity within one to several years after treatment. Over the 

long term, taxa would indirectly benefit from the removal of fish predation. 

Impacts on amphibian populations and communities would be direct, short term, 
E NVIRONMENTAL C ONSEQUENCES

276 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

and minor. Potential direct and indirect impacts on downstream native fish would 

be negligible. 

Cumulative Impacts 

Under alternative D, cumulative adverse impacts on all aquatic organisms would 

be less than that described for alternative A, since all 91 lakes would eventually 

be fishless, thus eliminating the adverse impacts associated with fish presence. 

However, cumulative impacts under alternative D would still occur, even with 

the added beneficial effects of fish removal because there are so many other 

actions that would adversely affect all the groups of aquatic organisms in the 

region. 

Overall, the impacts associated with other actions in the region, added to the 

long-term beneficial effects predicted under alternative D, would be expected to 

result in negligible to minor adverse impacts on plankton, macroinvertebrate, 

amphibian, and native fish, both at an individual lake and in the region. 

Conclusion 

Table 32 summarizes the direct impacts expected, by numbers of lakes, for 

plankton, macroinvertebrates, amphibians, and native fish. 

Aquatic organisms (including plankton, macroinvertebrates, and amphibians) 

would continue to experience long-term negligible to minor adverse impacts 

from fish predation and competition until stocked populations of fish gradually 

died out or were removed through treatment. Once these stocked fish are gone, 

native aquatic communities would eventually revert to predisturbance (that is, 

prestocking) conditions, and this would result in long-term beneficial impacts on 

native aquatic organisms. 

Removal of reproducing populations of fish from all study area lakes in the North 

Cascades Complex would eventually result in long-term beneficial effects on 

aquatic organisms in those lakes where removal proved feasible; however, 

removal of reproducing fish populations from study area lakes would take many 

years. Until fish are removed, long-term minor to major adverse impacts on 

aquatic organisms would persist as described in alternative A. 

Mechanical methods of fish removal (netting, trapping, spawning habitat 

exclusion) would have short-term negligible to minor adverse impacts on certain 

aquatic organisms. Chemical methods of fish removal (application of the 

piscicide antimycin) would have short-term negligible to moderate adverse 

impacts on certain aquatic organisms. 

Long-term minor to moderate adverse impacts on native fish would continue to 

be associated with hybridization between native and nonnative fish. The risk of 

hybridization would decline over the long term as reproducing populations of 

fish are eventually removed from study area lakes in the North Cascades 

Complex. The risk of hybridization, however, would not be entirely eliminated 

primarily because nonnative fish are now present in many drainages throughout 

the North Cascades Complex. 
Aquatic Organisms 

ENVIRONMENTAL IMPACT STATEMENT 277

Compared to alternative A, there would be a long-term beneficial cumulative 

impact on populations of native aquatic organisms because all study area lakes in 

the North Cascades Complex would eventually become fishless. Short- and longterm adverse cumulative impacts on aquatic organisms from threats other than 

nonnative fish would vary widely depending upon trends in aquatic ecosystem 

stressors such as air pollution, development in surrounding watersheds, and 

climate change. 

Impairment of aquatic organisms across the study area would not occur under 

alternative D. 
278 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Black bears are 

omnivores that will eat

any kind of food (plant

or animal), including

fish, if the opportunity 

presents itself.

WILDLIFE 

The wildlife potentially affected by the proposed alternatives include mammals, 

birds, and reptiles that are either native to lake habitats in the North Cascades 

Complex or are occurring in high mountain lakes in the North Cascades Complex 

due to the presence of stocked fish. Amphibians and fish are discussed in the 

section titled “Aquatic Organisms.” Additionally, wildlife inhabiting drainages 

downstream from lakes in the North Cascades Complex may also be affected by 

mountain lakes fishery management decisions. Impacts would occur from 

stocking or fish removal and associated activities under proposed management 

actions. 

This section describes the methods used to analyze impacts on wildlife and 

results of the analysis. The following section discusses the regulations and 

policies used to guide NPS decision making, in addition to the assumptions and 

thresholds used to analyze impacts on wildlife. 

GUIDING REGULATIONS AND POLICIES 

The General Management Plan (NPS 1988b) includes the following 

management objectives that are relevant to overall natural resources, including 

wildlife, for the North Cascades Complex: 

Increase knowledge and understanding of the interrelationships of the 

natural processes, and of methods for implementation of appropriate 

actions. 

Preserve, maintain, or restore, where feasible, the primary natural resources 

and those ecological relationships and processes. 

Manage the natural resources as an integral part of a regional ecosystem. 

Provide opportunity for research in as natural a system as possible. 

The Strategic Plan (NPS 2000a) includes goals for preserving resources in the 

North Cascades Complex that are consistent with the goals and objectives of this 

analysis. Mission Goal I.a. states that 

Natural and cultural resources and associated values of the North Cascades 

National Park Service Complex are protected, restored, and maintained in 

good condition and managed within their broader ecosystem and cultural 

context. 

Servicewide NPS regulations and policies, including the NPS Organic Act of 

1916, NPS Management Policies (NPS 2001a), and NPS Reference Manual 77, 

Natural Resource Management, also direct national parks to provide for the 

protection of park resources. The Organic Act directs national parks to conserve 

wildlife unimpaired for future generations and is interpreted to mean that native 

animal life are to be protected and perpetuated as part of a park unit’s natural 
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 279

ecosystem. Parks rely on natural processes to control populations of native 

species to the greatest extent possible; otherwise, they are protected from harvest, 

harassment, or harm by human activities. The NPS Management Policies (NPS 

2001a) make restoration of native species a high priority. Management goals for 

wildlife include maintaining components and processes of naturally evolving 

park ecosystems, including natural abundance, diversity, and ecological integrity 

of plants and animals (NPS 2001a, 4.1). Policies in the NPS Natural Resources 

Management Guidelines state, “the National Park Service will seek to perpetuate 

the native animal life as part of the natural ecosystem of parks” and that “native 

animal populations will be protected against . . . destruction . . . or harm through 

human actions.” 

METHODOLOGY AND ASSUMPTIONS 

The following discussion describes the methodology used to evaluate the impacts 

of the proposed alternatives on wildlife in the North Cascades Complex. Analysis 

methods are qualitative and are based on anecdotal evidence and field 

observations by NPS staff, reviews of existing data and literature, and best 

professional judgment. NPS staff provided information on species distribution in 

the North Cascades Complex. 

The analysis presented in this section assumes that the historic and current 

stocking in mountain lakes has created favorable ecological conditions for 

piscivorous (fish eating) wildlife that previously were unlikely to inhabit these 

lakes due to lack of favorable resources. Piscivorous wildlife or other species that 

eat fish opportunistically are now present at a number of lakes in the North 

Cascades Complex because they have become accustomed to the presence of fish 

in previously fishless lakes. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The geographic area evaluated for impacts on wildlife includes the North 

Cascades Complex, which is comprised of the north and south units of North 

Cascades National Park, Ross Lake National Recreation Area, and Lake Chelan 

National Recreation Area. More specifically, these impacts were evaluated for 

wildlife likely to occur in or near the 91 mountain lakes in the North Cascades 

Complex with a history of fish stocking, or those species that would be disturbed 

by management activities; for example, aircraft and helicopter noise would 

disturb wildlife during stocking or lake treatment activities. Impacts on wildlife 

inhabiting the drainage basins that extend beyond the North Cascades Complex 

boundaries are also considered because stocking or removing fish that migrate 

downstream from high mountain lakes may impact wildlife that use those fish as 

a food resource. 

O UTCOMES OF M ANAGEMENT A CTIONS

Several of the management actions that would be applied to lakes under each of 

the action alternatives have potential multiple outcomes, depending on the results 
E NVIRONMENTAL C ONSEQUENCES

280 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

of future monitoring and adaptive management decisions made based on these 

results. Therefore, for the purpose of this plan/EIS, the focus is on the initial 

outcome of the management actions, with the assumption that the lakes would 

either have fish or not have fish, based on the initial results of the actions taken. 

It is recognized that these conditions may change in some of the lakes due to 

decisions made under the proposed mountain lakes fishery monitoring plan 

presented in appendix F. If future monitoring indicates that fish presence has 

caused unacceptable changes to native biota, and as a result, fish are removed or 

reduced, impacts would also be reduced from what is presented here. 

I MPACT C RITERIA AND M ETHODOLOGY

Potential impacts on wildlife and wildlife habitat were evaluated based on the 

species present and their association with stocked fish, as well as the effects of 

stocking or lake treatment methods associated with fish removal. Information on 

habitat and other existing data were acquired from staff at the North Cascades 

Complex, the WDFW, U.S. Fish and Wildlife Service, and available literature. 

Methods to evaluate impacts on wildlife use alternative A as the baseline 

condition against which the action alternatives are compared because it 

represents current management practices. The analysis focuses on effects to 

wildlife from fish populations in mountain lakes, as well as impacts incurred as a 

result of management activities and removal of fish at the population and 

community levels. A population is defined as a group of individuals within a 

given species that are reproductively isolated from other groups and have 

geographically defined distributions. Communities are defined as the interacting 

populations of all species in a resource category. Literature on wildlife responses 

to noise provided available research to assess potential impacts on species from 

the use of helicopters or fixed-wing aircraft during lake management or lake 

treatment activities in the North Cascades Complex. 

I MPACT T HRESHOLD D EFINITIONS

The following thresholds were used to determine the magnitude of effects on 

wildlife and wildlife habitat as a result of implementation of any of the 

alternatives, including stocking and treatment methods: 

Negligible. An action would result in no observable or measurable impacts on 

native wildlife species, their habitats, or the natural processes sustaining them 

and would be of short duration, localized, and well within natural population 

fluctuations. 

Minor. An action would result in detectable impacts, but they would not be 

expected to result in substantial population fluctuations and would not be 

expected to have any measurable long-term effects on native species, their 

habitats, or the natural processes sustaining them. Occasional responses to 

disturbance by some individuals would be expected, but without interference to 

feeding, reproduction, or other factors affecting population levels. 
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 281

Moderate. An action would result in detectable impacts on native wildlife, their 

habitats, or the natural processes sustaining them. Key ecosystem processes may 

experience disruptions that would be outside natural range of fluctuation (but 

would return to natural conditions). Sufficient habitat would remain functional to 

maintain viability of native wildlife populations. 

Major. An action would result in detectable impacts on native wildlife, their 

habitats, or the natural processes sustaining them. Key ecosystem processes 

might be disrupted permanently. Adverse responses to disturbance by some 

individuals would be expected, with negative impacts on feeding, reproduction, 

or other factors resulting in a long-term decrease in population numbers and 

genetic variability. 

Impairment. An action would disrupt ecosystem processes resulting in 

elimination of a species or large population declines, locally and range-wide. In 

addition, these adverse, major impacts on the North Cascades Complex’s 

resources and values would 

contribute to deterioration of wildlife resources and values to the extent 

that the purpose of the North Cascades Complex would not be fulfilled as 

established in its enabling legislation 

affect resources key to the natural or cultural integrity or opportunities for 

enjoyment in the North Cascades Complex 

affect the resource whose conservation is identified as a goal in the 

General Management Plan (NPS 1988b) or other planning documents for 

the North Cascades Complex 

IMPACTS OF THE 

ALTERNATIVES ON WILDLIFE 

This section analyzes impacts for each of the four alternatives. The first section 

under each alternative addresses impacts that would result from stocking 

decisions made for each of the 91 lakes. The impacts are related to the numbers 

of stocked fish that would remain in the subject lakes, as well as disturbance 

from stocking activities. Next, a section is provided to address impacts related to 

the various lake treatment methods. Finally, cumulative impacts are discussed, 

and an overall summary of impacts is presented at the end of each alternative 

analysis. 

Many wildlife species inhabiting the North Cascades Complex that are 

considered in this plan/EIS are not directly linked to fish or aquatic habitats, but 

under any of the alternatives, management activities resulting in increased human 

presence and the noise from fixed-wing aircraft or helicopters have the potential 

to adversely affect wildlife. 
E NVIRONMENTAL C ONSEQUENCES

282 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

The current mountain lakes fishery management activities at the North Cascades 

Complex, which are described in the “Alternatives” chapter, would continue 

under the no-action alternative. 

For detailed information on the 91 lakes, refer to table 5 and figure 4 in the 

“Alternatives” chapter and appendix E. 

Impacts of Current 

Fish Stocking on Wildlife 

The majority of impacts on wildlife under alternative A would be related to the 

number of fish stocked and/or density of reproducing fish in the lakes. To a lesser 

degree, noise and disturbance associated with stocking activities are also 

considered. As described in the “Alternatives” chapter, current stocking is 

accomplished by packing fry into lakes or dropping fry from fixed-wing aircraft. 

Impacts on wildlife from helicopters are only discussed under alternatives B, C, 

and D because, under those alternatives, helicopters would only be used to apply 

treatments to remove fish; they are no longer used to stock fish in the North 

Cascades Complex. Stocking would occur infrequently, anywhere from annually 

to every 10 years, and would vary from lake to lake. As described in the 

“Alternatives” chapter, a fly-over occurs once per stocking cycle, and the plane 

flies over the lake very briefly, typically less than a minute. The preferred 

stocking method is for one or two people to backpack the fish to the lake. In 

some cases, backpack stocking requires overnight camping because of the 

extensive distances. Mitigation measures to prevent impacts from campers 

around lakes are outlined below and in appendix I. 

In the 62 lakes under alternative A that have been stocked with fish, impacts on 

wildlife would be negligible to minor. Stocking fish in the North Cascades 

Complex has altered lake community dynamics over time. Many wildlife species 

that historically did not inhabit the high mountain lakes have expanded their 

ranges to include new areas where fish have become abundant. Under alternative 

A, fish-eating wildlife would continue to use the lakes in the North Cascades 

Complex that are stocked. Fish are a primary food source for several species that 

are observed at or regularly inhabit mountain lakes in the North Cascades 

Complex. These species include river otters and several bird species such as 

mergansers, belted kingfishers, and ospreys. Ospreys have been seen feeding on 

fish at several lakes in the North Cascades Complex, although they do not nest at 

the lakes. For other species, like the garter snake, there may be adverse impacts 

from fish presence because fish would compete for the same prey (salamanders, 

insects). 

Impacts from stocking activities associated with fixed-wing aircraft and 

backpackers would be expected to affect the species discussed previously, 

including species that do not live in or next to the lakes but inhabit nearby woods. 

Those species are deer, elk, mountain goats, bats, and a variety of raptors and 

passerine birds. The intensity of noise impacts would decrease with increased 

Fish are a primary 

food source for bird

species such as the 

belted kingfisher.
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 283

distance from the lakes because the intensity of sound decreases with distance 

(there is generally a 6 decibel reduction in sound level for each doubling of 

distance from a noise source due to spherical spreading loss), plus the trees 

provide some buffering capacity. Noise disturbance would occur as aircraft 

approach and fly over the lakes during stocking. Stocking by fixed-wing aircraft 

occurs during the summer and fall months when wildlife are active. Noise from 

aircraft would approach 70 to 80 decibels, compared to estimated typical 

background levels of 20 to 40 decibels in the North Cascades Complex (see 

table 33). 

Noise at high levels can cause behavioral and physiological reactions in wildlife 

that vary by species and individuals (Knight and Gutzwiller 1995). Additional 

factors affecting wildlife response to noise include duration and previous 

exposure to noise, habitat type, season, activity occurring at time of disturbance, 

and the existing physical condition of the individual (Radle 2004). Physiological 

responses in wildlife include an increased heart rate and stress. Behavioral 

responses vary from mild reactions, such as changes in body position, to severe 

panic and escape reactions that interrupt normal activities or, in extreme cases, 

abandonment of normal territories or home ranges. For ungulates such as deer 

and elk, behavioral reactions seem to be related to a past experience with human 

and aircraft disturbance. In previous studies on ungulate responses to aircraft 

overflights in national parks, herd response to aircraft varied from no response to 

panic and escape (DOI 1988). Birds typically flush from a nest or perch in 

response to a disturbance but will usually return within a few minutes (NPC 

2004). 

TABLE 33: SOUND LEVEL COMPARISON CHART* 

Decibels How it Feels Equivalent Sounds 

140–160 Near permanent 

damage level from 

short exposure 

Large caliber rifles such as .243, 30–06 

130–140 Pain to ears .22 caliber weapon 

100 Very loud, conversation 

stops 

Air compressor at 20 feet; garbage trucks and city buses; 

power lawnmower; diesel truck at 25 feet 

90 Intolerable for phone 

use 

Steady flow of freeway traffic; 10 horsepower outboard 

motor; garbage disposal; helicopter at 1,000 feet 

(70–90 decibels) 

70–80 Fixed-wing aircraft or helicopter flyover; automatic 

dishwasher or vacuum cleaner (80 decibels) 

60 Quiet Window air conditioner in room; normal conversation 

50 Sleep interference Quiet home in evening 

40 Library; frontcountry camping or developed site 

30 Soft whisper 

20 In a quiet house at midnight; leaves rustling; remote sites 

(Death Valley, interior wooded areas with backcounty 

camping) 

Note: 

* Modified from Pictured Rocks National Lakeshore Personal Watercraft Use Final Environmental 

Impact Statement, 2003; Tetra Tech 1987; U.S. Forest Service 2001.
E NVIRONMENTAL C ONSEQUENCES

284 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Most noise disturbances would not be severe enough to cause detectable changes 

in population size or reproductive success (Knight and Gutzwiller 1995). Aircraft 

flyovers for stocking would occur from every 1 to 10 years, and the duration of 

each flyover would be short. Backpackers may trample vegetation while stocking 

fish at lakeshores; however, this impact is expected to be negligible, and habitat 

would return to pre-disturbance conditions. Wildlife in or near lakes may 

experience short-term and temporary disturbances from stocking activities, such 

as interruption of activity or temporary flushing or fleeing, but this would not 

change population structure or function. Many wildlife species such as bats, 

rodents, and forest-dwelling birds would incur only negligible or no impacts 

under alternative A because stocking would occur far enough away from these 

species that normal activities would not be disturbed. 

In the 29 lakes that were historically stocked but are currently fishless, impacts 

on wildlife would be negligible. Under alternative A, the 29 lakes would remain 

fishless. 

Impairment of wildlife species across the study area would not occur from 

current fish stocking under alternative A. 

Impacts of Current 

Lake Treatment Methods on Wildlife 

Under alternative A (no action), none of the 91 lakes addressed in this plan/EIS 

are currently being treated. 

Cumulative Impacts 

Recreational use of the lakes and surrounding drainages would contribute 

negligible to minor impacts on the wildlife in the North Cascades Complex. 

Some of this disturbance to wildlife from backpackers, campers, and non-anglers 

would be mitigated by natural topography of the landscape and forested areas 

that provide refuge. Other species that inhabit the more open lands would 

eventually become accustomed to human presence or move to other areas. 

On a landscape scale, the piscivorous wildlife generally benefit from the presence 

of stocked fish in mountain lakes where resources were previously lacking. 

Continued presence of fish in North Cascades Complex lakes, coupled with 

continued presence of fish in lakes on surrounding lands, would tend to make 

piscivorous wildlife more widespread and increase their populations. Conversely, 

it is likely that species unable to adapt to stocked fish would, or have already 

become, locally reduced or eliminated over the past 100 years. 

There would be continued, localized, and sporadic effects on wildlife from 

logging and dams and reservoir construction that has occurred and continues to 

occur outside the North Cascades Complex, including in connected watersheds. 

These actions can cause severe habitat loss for many forest-dwelling species such 

as birds, bats, and rodents. The loss of adjacent habitats places more pressure on 

the wilderness lands in the North Cascades Complex to provide habitat for 

wildlife, especially larger-bodied species with broad home ranges. 
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 285

Other sources of impacts continue to occur that may affect the health and 

viability of species dependent on aquatic resources. There is concern about 

persistent organic pollutants and methyl-mercury found in some lakes in the 

North Cascades Complex, which appear to result from airborne pollutants being 

deposited on snow and washed into lakes. There is the potential for increased 

acid rain from emissions related to the development of an additional power plant 

in the area; emissions would contribute to an increase in lake acidity and metal 

availability. In some cases, the concentrations of some of these pollutants in the 

water in preliminary studies appear to be high enough to raise concerns that, in 

conjunction with other negative influences, organisms at higher trophic levels 

may be affected. Toxins can be passed from the tissue of one organism to those 

that feed on it, meaning that a toxin can move up the food chain and biomagnify 

to higher concentrations in the top predators (such as osprey or river otters) in a 

lake to the point where pollutants would cause reproductive failure. If that 

occurred, then the cumulative effects of pollutants coupled with other impacts, 

perhaps from nonnative fish, might eliminate that predator species from certain 

lakes or even cause a more general decline in the population. 

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus impacts from potential airborne pollution, added to the 

impacts predicted under alternative A, would be expected to result in long-term, 

minor, adverse cumulative impacts on wildlife populations and communities in 

the region. 

Conclusion 

The historic and current stocking of fish created suitable conditions for 

piscivorous wildlife, such as fish-eating ducks, while potentially restricting 

populations of other species, such as amphibians, that are prey for several 

wildlife species. Impacts from activities associated with periodic fixed-wing 

aircraft stocking (noise disturbance) and backpack stocking (human presence and 

habitat trampling) under alternative A would be short term negligible to minor 

and adverse on wildlife at or near the lakes. Animals that roost or dwell further 

away from lakes, such an ungulates, bats, rodents, and many forest-dwelling 

birds, would incur short-term negligible adverse impacts or no impacts from 

stocking activities. None of the 91 lakes are currently treated for fish removal 

under alternative A; therefore, wildlife in or near the lakes would not incur 

impacts from lake treatments. 

The impacts associated with other projects and fishery management actions in the 

area, plus impacts from potential airborne pollution, added to the impacts 

predicted under alternative A, would result in long-term minor adverse 

cumulative impacts on wildlife populations and communities in the region. 

Impairment of wildlife species across the study area would not occur under 

alternative A. 
E NVIRONMENTAL C ONSEQUENCES

286 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The goal of this alternative is to eliminate or reduce reproducing fish from lakes 

in the study area. Restocking of nonreproducing fish would be allowed only 

where biological resources would be protected. Based on best available science, 

some lakes would be restocked with nonreproducing fish at low densities once 

reproducing fish have been removed. Lakes where critical information is missing 

would not be stocked until that information becomes available. An extensive 

monitoring program (see appendix F) would be implemented in order to adjust 

management in the future to avoid unacceptable effects on native biota from fish 

presence. 

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed 

Fish Stocking on Wildlife 

Under alternative B, impacts of fish stocking on wildlife, including impacts 

related to the noise and disturbance associated with periodic stocking activity, 

would be similar to alternative A. Up to 49 lakes would eventually be fishless, 

compared to 29 under alternative A, and all other lakes would have low densities 

of fish or be evaluated prior to restocking or fish removal. Removing high 

densities of fish and/or eliminating fish would result in minor impacts on 

piscivorous wildlife. Several lakes with high fish densities would be treated to 

remove all fish. Piscivorous species inhabiting these lakes, such as mergansers or 

otters, would be displaced to other lakes in search of food if a lake is returned to 

a fishless state. Species that only occasionally feed on fish if available, such as 

black bears, would incur negligible impacts under alternative B; however, the 

consumption of fish by wildlife in the North Cascades Complex is not a natural 

occurrence because fish are not native to the high mountain lakes. Fish stocking 

in the North Cascades Complex has created a reliance on lake resources for 

piscivorous wildlife that now inhabit the area and would be adversely impacted 

by fish removal. 

Impacts on wildlife would be negligible in the 29 lakes that are currently fishless 

and would not be stocked under alternative B. 

Impairment of wildlife species across the study area would not occur from fish 

stocking under alternative B. 

Impacts of Proposed Lake 

Treatment Methods on Wildlife 

The treatment methods proposed for each lake were selected based on the type of 

fish population present (reproducing vs. nonreproducing), and physical 

Common mergansers 

have been observed on 

Coon Lake and are 

frequently seen along

the Stehekin and Skagit

rivers (female-top 

sketch, male-lower

sketch).
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 287

Bioaccumulation: 

The accumulation of 

a harmful substance 

such as a heavy 

metal or an 

organochlorine in a 

biological organism, 

especially one that 

forms part of the 

food chain. 

characteristics of the lake, such as depth and surface area. Each proposed method 

described below may or may not impact wildlife in the North Cascades Complex. 

Natural Methods. Under alternative B, 12 previously stocked lakes would be 

treated using natural methods. This method is only effective in lakes without 

extensive natural fish reproduction. Natural removal methods involve no direct 

actions in each lake, very limited human presence, and no mechanized transport 

(such as helicopters); therefore, impacts of natural trout removal would be 

negligible on wildlife. 

Mechanical Methods. Under alternative B, up to 8 lakes are being considered 

for mechanical treatment. For gillnetting, helicopters would transport equipment 

and lower it to the site, and a team would set nets by hand using float tubes. If 

traps are used, they would also be set by hand, generally near lake inlets and 

outlets. The method of gillnetting may unintentionally ensnare nontarget animals 

such as beavers, river otters, mergansers, ospreys, and salamanders, and traps 

would also capture small nontarget animals. Standard mitigation would require 

ground crews to check nets and traps frequently and release any ensnared 

animals. Although the impacts on individuals, family units, or localized 

populations of any associated loss would be serious, populations of these animals 

in the North Cascades Complex would only experience minor impacts. 

Electrofishing would be used in lakes where a more thorough removal of all fish 

is required. Electrofishing would not adversely affect any terrestrial wildlife, and 

any waterfowl or larger aquatic mammals would avoid the areas being treated. If 

a backpack generator is needed, minor short-term impacts would result from 

motor noise, which may cause animals to temporarily flee or avoid the area being 

treated. 

To conduct gillnetting, crews would be required to camp at a lake for several 

days. Temporary displacement of sensitive wildlife may occur during extended 

periods of continuous human presence; however, animals are expected to return 

to areas after a disturbance is removed. 

Helicopters used for lake treatment have the potential to stress wildlife, 

depending on the species and individual response. Helicopters hovering overhead 

are known to generate noise levels of about 70 to 90 decibels, compared to 

background levels of 20 to 40 decibels (refer to table 33). Mountain goats are 

particularly stressed by helicopters and exhibit severe fright and escape responses 

in the presence of a helicopter (NPS 1994). Other species, such as raptors, may 

temporarily flush from a nest or perch in the presence of a helicopter but would 

return after take-off. Helicopters hover over a lake for only a short period of time 

before landing, and the presence of trees may provide a sight and sound barrier 

for wildlife in nearby forests. Impacts on wildlife on or near the lakeshore, 

especially waterfowl and mammals such as otters that nest or den along the 

shoreline, would be minor, short term, and very infrequent. Impacts would be 

negligible for those animals occurring farther away from the lakes, such as bear, 

deer, elk, and many raptors and songbirds. 

Chemical Method. Up to 18 lakes under alternative B would be chemically 

treated to remove fish using the piscicide, antimycin. The chemical method 
E NVIRONMENTAL C ONSEQUENCES

288 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

would be used in large lakes with reproducing fish populations where mechanical 

removal methods would not be practical. Antimycin is very specific in its action; 

when applied at recommended dosages, it affects fish but is unlikely to affect 

waterfowl or mammals (Schnick 1974). Also, antimycin is used in such slight 

quantities that residues are extremely small, and it has not been shown to 

bioaccumulate (Schnick 1974). 

Impacts of fish removal using the chemical antimycin would be negligible to 

minor. The use of small motorized boats to apply antimycin would cause shortterm noise disturbances to waterfowl on the lake or other species (such as 

beavers or otters) around the immediate lake shore; however, these disturbances 

would be short term and negligible for those species. 

Cumulative Impacts 

Cumulative impacts on wildlife under alternative B would be very similar to 

those described for alternative A, with some additional effects on piscivorous 

wildlife that would be displaced from lakes where fish are removed. 

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus potential impacts from possible airborne pollution, added 

to the residual adverse and long-term beneficial effects predicted under 

alternative B, would be expected to result in long-term minor adverse cumulative 

impacts on wildlife populations and communities in the region. 

Conclusion 

The historic and current stocking of fish created suitable conditions for 

piscivorous wildlife, such as fish-eating ducks, while potentially restricting 

populations of other species, such as amphibians, that are prey for several 

wildlife species. Removal of fish would result in the loss of a food source for 

fish-dependent species, requiring them to disperse to other areas in search of 

resources; because of this, piscivorous wildlife would incur long-term negligible 

to minor adverse impacts when lakes are returned to fishless conditions. Stocking 

activities would decrease, and wildlife at or near the lakes would incur short-term 

negligible to minor adverse impacts from periodic fixed-wing aircraft stocking 

(noise disturbance) and backpack stocking (human presence and habitat 

trampling) that would continue under alternative B but to a lesser degree than 

under alternative A. Stocking activities would have short-term negligible adverse 

impacts or no impacts on animals, such as ungulates, bats, rodents, and many 

forest-dwelling birds, that roost or dwell further away from the lakes. Mechanical 

and chemical treatment methods used to remove fish under alternative B would 

result in short-term negligible to minor adverse impacts on wildlife, with shortterm disturbance to birds and mammals that inhabit the lake and lakeshore from 

the noise of human presence and helicopters used to transport equipment for 

mechanical treatment. 

The impacts associated with other projects and fishery management actions in the 

area, plus impacts from potential airborne pollution, added to the residual adverse 

and long-term beneficial effects predicted under alternative B, would be expected 

Noise disturbances 

during aircraft

stocking would affect

some wildlife species 

that inhabit nearby 

woods, such as this 

hanging bat.
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 289

to result in long-term minor adverse cumulative impacts on wildlife populations 

and communities in the region. 

Impairment of wildlife species across the study area would not occur under 

alternative B. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

The goal of this alternative is to eliminate all fish in lakes in the national park and 

reduce or eliminate reproducing fish in the Lake Chelan and Ross Lake National 

Recreation Areas, but still allow for some sport fishing in these two areas. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed 

Fish Stocking on Wildlife 

The types of impacts on wildlife from fish stocking would be similar to those 

described for alternative A; however, there would be 80 lakes that would be 

fishless compared to 29 lakes under alternative A, with reductions in fish 

densities in the national recreation area lakes. Lakes with high densities of fish 

would be treated or evaluated, then treated to remove the fish. Loss of fish 

resources in these lakes would result in minor to possibly moderate impacts on 

piscivorous wildlife. Piscivorous species, such as mergansers or otters, would 

move to other lakes in search of food if a lake is returned to a fishless state. Some 

wildlife, such as black bears, that feed on fish opportunistically would incur 

negligible impacts under alternative C because the availability of fish would be 

less. The consumption of fish by wildlife is not a natural occurrence because fish 

are not native to the high mountain lakes in the North Cascades Complex, and 

fish stocking has created a reliance on lake resources for piscivorous wildlife that 

now inhabit the area and would be adversely impacted by fish removal. 

Under alternative C, 29 historically stocked, but currently fishless lakes, would 

remain fishless. Impacts on wildlife would be negligible in the 29 lakes that 

would remain fishless. 

Impairment of wildlife species across the study area would not occur from fish 

stocking under alternative C. 

Impacts of Proposed Lake 

Treatment Methods on Wildlife 

Under alternative C, the types of impacts associated with the various lake 

treatment methods would be the same as described for alternative B; however, 

the number of lakes affected by those treatments would increase, with more 
E NVIRONMENTAL C ONSEQUENCES

290 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

wildlife incurring short-term minor impacts from chemical or mechanical 

treatments to remove fish. 

Natural Methods. Under alternative C, 21 previously stocked lakes would be 

treated using natural methods (lakes would not be restocked, and fish would die 

out from fishing pressure and natural mortality). Because natural removal 

methods involve no direct actions in each lake, very limited human presence, and 

no mechanized transport (such as helicopters), impacts of natural trout removal 

would be negligible on wildlife. 

Mechanical Methods. Under alternative C, up to 10 lakes are being considered 

for mechanical treatment, an increase of 2 lakes over the number proposed for 

mechanical treatment under alternative B. Impacts relating to the presence of 

ground crews and activities such as electrofishing, helicopter use, and netting, 

would be the same as described for alternative B but would occur at slightly more 

lakes. Although the impacts on individuals, family units, or localized populations 

of any associated loss would be serious, populations of these animals in the North 

Cascades Complex would only experience minor impacts. Minor short-term 

impacts on some species, such as waterfowl and amphibians, would result from 

the presence of ground crews and helicopter use. 

Chemical Method. There would be 25 lakes treated with the piscicide, 

antimycin, under alternative C, an increase of 7 lakes over the number that would 

be chemically treated under alternative B. Impacts on nontarget wildlife would be 

negligible to minor, as described under alternative B. Noise-related impacts from 

helicopter and small-boat use during chemical treatment would be short term and 

minor, but would occur at more lakes over time. 

Cumulative Impacts 

Cumulative impacts under alternative C would be similar to those described 

under alternative A, but with additional impacts on piscivorous wildlife that have 

become dependent on fish in the stocked lakes. 

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus potential impacts from increased airborne pollution, 

added to the impacts predicted under alternative C, would be expected to result in 

long-term minor adverse cumulative impacts on wildlife populations and 

communities in the region. 

Conclusion 

The historic and current stocking of fish created suitable conditions for 

piscivorous wildlife, such as fish-eating ducks, while potentially restricting 

populations of other species, such as amphibians, that are prey for several 

wildlife species. Removal of fish would result in the loss of a food source for 

fish-dependent species, requiring them to disperse to other areas in search of 

resources; because of this, piscivorous wildlife would incur long-term negligible 

to minor adverse impacts when lakes are returned to fishless conditions. Stocking 

activities would substantially decrease, and wildlife at or near the lakes would 

incur short-term negligible to minor adverse impacts from periodic fixed-wing 
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 291

aircraft stocking (noise disturbance) and backpack stocking (human presence and 

habitat trampling) that would continue under alternative C but to a much lesser 

degree than under alternatives A and B. Stocking activities would have shortterm negligible adverse impacts or no impacts on animals, such as ungulates, 

bats, rodents, and many forest-dwelling birds, that roost or dwell further away 

from the lakes. Mechanical and chemical treatment methods used to remove fish 

under alternative C would result in short-term negligible to minor adverse 

impacts on wildlife, with short-term disturbance to birds and mammals that 

inhabit the lake and lakeshore from the noise of human presence and helicopters 

used to transport equipment for mechanical treatment. 

The impacts associated with other projects and fishery management actions in the 

area, plus impacts from potential airborne pollution, added to the residual adverse 

and long-term beneficial effects predicted under alternative C, would be expected 

to result in long-term minor adverse cumulative impacts on wildlife populations 

and communities in the region. 

Impairment of wildlife species across the study area would not occur under 

alternative C. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS

Sport-fishing opportunities in most of the study area lakes would generally be 

eliminated within a period of 5 years. Self-sustaining (reproducing) populations 

of fish would be gradually removed over time—the rate of removal would 

depend on resource (funding and personnel) availability and differences among 

fish removal methods. Complete removal of self-sustaining populations of fish in 

some of the larger, deeper lakes might not be feasible (9 lakes potentially fall into 

this category—refer to table 7 in the “Alternatives” chapter). These lakes would 

continue to provide sport-fishing opportunities for the foreseeable future, and the 

goal of complete removal might never be achieved. The phase out of nonnative 

fish would allow for the protection of biological resources in and around the 

lakes. 

The “Alternatives” chapter provides a detailed description of alternative D. For 

more information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed 

Fish Stocking on Wildlife 

Under alternative D, the 29 lakes that are currently fishless would remain 

fishless, and fish stocking would be gradually phased out. Nine lakes would be 

evaluated for the feasibility of fish removal; if complete removal of fish were not 

possible, then density would be reduced. The remaining 62 lakes would be 

treated to remove fish over time. Loss of fish resources in the lakes that would 

become fishless would result in minor to possibly moderate impacts on 

piscivorous wildlife. Piscivorous species, such as loons, mergansers, or otters, 

would have to find alternative areas of suitable habitat outside the North 
E NVIRONMENTAL C ONSEQUENCES

292 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Cascades Complex or would die out; however, piscivorous wildlife inhabiting 

high mountain lakes are not naturally occurring in the North Cascades Complex, 

and removal of fish would eventually return the habitat to its condition prior to 

human manipulation. Some wildlife, such as black bears, that feed on fish 

opportunistically would incur negligible impacts under alternative D because the 

availability of fish would be less. 

Impairment of wildlife species across the study area would not occur from fish 

stocking under alternative D because stocking would no longer occur. 

Impacts of Proposed Lake 

Treatment Methods on Wildlife 

Under alternative D, the types of impacts associated with the various lake 

treatment methods would be the same as described for alternative B; however, 

the number of lakes affected by those treatments would increase, with more 

wildlife incurring short-term minor impacts from chemical and mechanical 

treatments. 

Natural Methods. Under alternative D, 26 lakes currently stocked under 

alternative A would not be restocked, and fish would die out from fishing 

pressure and natural mortality. Because natural removal methods involve no 

direct actions within each lake, very limited human presence, and no mechanized 

transport (using helicopters) of equipment, impacts of natural trout removal 

would be negligible on wildlife. 

Mechanical Methods. Under alternative D, a total of 11 lakes are being 

considered for mechanical treatment, an increase of 1 lake over alternative C, and 

3 lakes more than alternative B. Impacts relating to the presence of ground crews, 

electrofishing, helicopters use, and netting would be the about the same as 

described for alternatives B and C. Although the impacts on species’ individuals, 

family units, or localized populations of any associated loss would be serious, 

populations of these animals in the North Cascades Complex would only 

experience minor impacts. Minor short-term impacts on some species, such as 

waterfowl and amphibians, would result from the presence of ground crews and 

helicopter use. 

Chemical Method. There would be 25 lakes chemically treated to remove fish 

using the piscicide, antimycin, the same as alternative C, but an increase of 

7 lakes over the number of lakes that would be chemically treated under 

alternative B. Impacts on nontarget wildlife would be negligible, as described 

under alternative B. Noise-related impacts from the helicopter and small boat 

used during lake treatment would be short term and minor but would occur at 

25 lakes over time. 

Cumulative Impacts 

Cumulative impacts under alternative D would be similar to those described 

under alternative A, but with additional impacts on piscivorous wildlife that have 

become dependent on fish in the stocked lakes. 
Wildlife 

ENVIRONMENTAL IMPACT STATEMENT 293

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus possible impacts from potential airborne pollution, added 

to the impacts predicted under alternative D, would be expected to result in minor 

adverse cumulative impacts on wildlife populations and communities in the 

region. 

Conclusion 

Alternative D would have long-term minor to moderate adverse impacts on fisheating wildlife in lakes that would become fishless. Removal of fish would result 

in the loss of habitat for fish-eating species, requiring them to relocate to other 

areas (potentially outside the North Cascades Complex) in search of resources, 

which would result in local population decreases for those species, returning the 

area to pre-stocked conditions. Under alternative D, stocking activities would be 

eliminated, a slight benefit to wildlife that have been disturbed by the noise and 

human disturbance associated with stocking activities. Mechanical and chemical 

treatment methods used to remove fish under alternative D would result in shortterm negligible to minor adverse impacts on wildlife, with short-term disturbance 

to birds and mammals that inhabit the lake and lakeshore from the noise of 

human presence and helicopters used to transport equipment for mechanical 

treatment. 

The impacts associated with other projects and fishery management actions in the 

area, plus impacts from potential airborne pollution, added to the residual adverse 

and long-term beneficial effects predicted under alternative D, would be expected 

to result in long-term minor adverse cumulative impacts on wildlife populations 

and communities in the region. 

Impairment of wildlife species across the study area would not occur under 

alternative D. 
294 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

SPECIAL STATUS SPECIES 

GUIDING REGULATIONS AND POLICIES 

Special status species of plants and wildlife are included in this section. The 

Endangered Species Act (16 USC 1531 et seq.) mandates that all federal agencies 

consider the potential effects of their actions on threatened and endangered 

species and species of special concern. If the NPS determines that an action may 

adversely affect a federally listed species, consultation with the U.S. Fish and 

Wildlife Service is required to ensure that the action would not jeopardize the 

species’ continued existence or result in the destruction or adverse modification 

of critical habitat. 

Informal consultation was initiated with the U.S. Fish and Wildlife Service and 

the National Marine Fisheries Service (now NOAA Fisheries) during the internal 

scoping period for this project. A list of species that are known to occur or may 

occur in the North Cascades Complex was requested. The U.S. Fish and Wildlife 

Service sent a list of federally listed species, by county occurrence; this list is 

included in appendix C. For the purpose of this analysis, only those species 

known to occur in the North Cascades Complex, and that would experience some 

level of impacts as a result of fishery management actions, are addressed in this 

section. 

This plan/EIS has been submitted to the U.S. Fish and Wildlife Service and 

NOAA Fisheries for review. If these two entities and other federal agencies agree 

that no adverse impacts on listed species are likely to occur, no further 

consultation would be required. If further consultation is needed, this plan/EIS is 

intended to meet the requirements of a biological assessment. 

If actions associated with any fishery management alternative are likely to 

adversely affect one or more of the federally listed threatened or endangered 

species identified at the North Cascades Complex, formal consultation would be 

initiated with the U.S. Fish and Wildlife Service, and a biological assessment 

would be prepared to document the potential effects to listed species. From the 

date that formal consultation is initiated, the U.S. Fish and Wildlife Service or 

NOAA Fisheries has 90 days to consult with the NPS and 45 days to prepare a 

biological opinion based on the biological assessment and other scientific 

sources. In the biological opinion, the biological assessment would state whether 

the proposed fishery management actions would likely jeopardize the continued 

existence of the listed species or result in the destruction or adverse modification 

of critical habitat. Such an opinion would most likely be the same as a 

determination of impairment. To ensure that a species would not be jeopardized 

by mountain lakes fishery management activities, the NPS would confer with the 

U.S. Fish and Wildlife Service or NOAA Fisheries to identify recommendations 

for reducing adverse impacts and would integrate those into the preferred 

alternative for fishery management in the North Cascades Complex. 

NPS Management Policies (NPS 2001a) state that the potential effects of agency 

actions will also be considered on state or locally listed species. The NPS is 

required to control access to critical habitat of such species and to perpetuate the 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 295

natural distribution and abundance of these species and the ecosystems upon 

which they depend. 

METHODOLOGY AND ASSUMPTIONS 

FOR SPECIAL STATUS WILDLIFE SPECIES

This section describes the methodology used to evaluate the impacts of the 

proposed alternatives on state and federally listed wildlife and plant species. State 

and federally listed species were identified through discussions with staff from 

the North Cascades Complex and informal consultation with the U.S. Fish and 

Wildlife Service, NOAA Fisheries, and the WDFW (see appendix C). The 

primary steps in assessing impacts on listed species were to determine 

which species inhabit areas likely to be affected by fishery management 

actions described in the alternatives 

current and future distribution of fishery management actions 

potential areas of impact as a result of implementation of any of the 

alternatives, including downstream areas 

The information contained in this analysis was obtained through best professional 

judgment of NPS staff from the North Cascades Complex and experts in fishery 

management, the U.S. Fish and Wildlife Service, WDFW, and available 

literature. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The geographic area evaluated for impacts on special status species includes the 

91 lakes in the North Cascades Complex (the study area) that have a history of 

fish presences as a result of documented or undocumented fish stocking. The 

North Cascades Complex is comprised of the north and south units of North 

Cascades National Park, Ross Lake National Recreation Area, and Lake Chelan 

National Recreation Area. For fish populations potentially affected by 

downstream colonization, impacts in downstream drainage basins that extend 

beyond the boundaries of North Cascades Complex are also considered. These 

basins include the Chilliwack River (Fraser River Basin), Lake Chelan Basin 

(including the Stehekin River and its tributaries), and the Skagit River and 

several of its tributaries. 

O UTCOMES OF THE M ANAGEMENT A CTIONS

Several of the management actions that would be applied to lakes under each of 

the action alternatives have potential multiple outcomes, depending on the results 

of future monitoring and adaptive management decisions. Therefore, for the 

purpose of this plan/EIS, the focus is on the initial outcome of the management 

actions and the assumption that the lakes either would have fish or would not, 

based on the initial results of the actions taken. It is recognized, however, that 
E NVIRONMENTAL C ONSEQUENCES

296 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

these conditions may change in some of the lakes due to decisions made under 

the proposed monitoring program and adaptive management approach described 

in the section titled “Adaptive Management” in the “Alternatives” chapter. If 

future monitoring indicates that fish presence has caused unacceptable changes to 

native biota, and as a result fish are removed or reduced, impacts may also be 

reduced from the levels presented in this “Special Status Species” section. 

I MPACT C RITERIA AND M ETHODOLOGY

Impacts on special status species include any activity that would be considered a 

“take” or cause harm to a species as defined under the Endangered Species Act, 

including harassment. A determination of the potential effects to listed species is 

treated very conservatively in order to provide maximum protection. Stocking 

fish in waters that were previously fishless can provide a certain species, such as 

a piscivorous species, with the opportunity to expand its range into areas 

previously unsuitable due to lack of food resources. While fish stocking has 

acknowledged benefits, it can also have negative effects through the introduction 

of nonnative species, which can alter dynamics of a community, with the 

resulting loss of ecological integrity. 

Potential impacts on special status species or their habitat were evaluated based 

on species presence, a species’ association with stocked fish, and the effects of 

stocking or lake treatment methods associated with fish removal. Also, where 

local surveys of fish distribution and abundance were available, existing data and 

professional knowledge were used to further assess the potential for impacts. 

The methods to evaluate impacts on special status species used alternative A as 

the baseline condition against which the action alternatives were compared 

because it represents current management. The analysis focused on the effects to 

special status species from stocked fish in mountain lakes, as well as impacts 

from other management activities. Literature on wildlife responses to noise 

provided available research to assess potential impacts on listed species known to 

occur in the North Cascades Complex. 

I MPACT T HRESHOLD D EFINITIONS 

FOR F EDERALLY L ISTED 

S PECIAL S TATUS W ILDLIFE S PECIES

The following thresholds were used to determine the magnitude of effects on 

federally listed special status species and their associated habitat that would 

result from implementation of any of the alternatives, including fish stocking and 

lake treatment methods to remove fish. Since impacts on native fish were already 

analyzed in detail in the “Aquatic Organisms” section in this chapter, the 

assessment of whether an effect on listed native fish would be likely was based 

on an examination of the same predictive factors and professional knowledge 

used in the analysis of aquatic organisms. The background information used for 

the analysis of impacts on native fish can be found in appendix G. 

No effect. When a proposed action would not affect a listed species or designated 

critical habitat. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 297

May affect / not likely to adversely affect. Effects on special status species are 

discountable (i.e., extremely unlikely to occur and not able to be meaningfully 

measured, detected, or evaluated) or are completely beneficial. 

May affect / likely to adversely affect. When an adverse impact to a listed 

species may occur as a direct or indirect result of proposed actions and the effect 

is not discountable or beneficial. 

Is likely to jeopardize proposed species / adversely modify proposed critical 

habitat (impairment). The appropriate conclusion when the NPS or the U.S. 

Fish and Wildlife Service identifies situations in which the proposal would 

jeopardize the continued existence of a proposed species or adversely modify 

critical habitat to a species within or outside the North Cascades Complex 

boundaries. 

State Listed and Special 

Status Wildlife Species 

The assessment of impacts on wildlife species listed by the state of Washington 

(but not at the federal level) used the same thresholds developed for the 

assessment of impacts on wildlife, in general; these are repeated below. 

Negligible. An action would result in no observable or measurable impacts on 

native wildlife species, their habitats, or the natural processes sustaining them 

and would be of short duration, localized, and well within natural population 

fluctuations. 

Minor. An action would result in detectable impacts, but they would not be 

expected to result in substantial population fluctuations and would not be 

expected to have any measurable long-term effects on native species, their 

habitats, or the natural processes sustaining them. Occasional responses to 

disturbance by some individuals would be expected, but without interference to 

feeding, reproduction, or other factors affecting population levels. 

Moderate. An action would result in detectable impacts on native wildlife, their 

habitats, or the natural processes sustaining them. Key ecosystem processes may 

experience disruptions that would be outside the natural range of fluctuation (but 

would return to natural conditions). Sufficient habitat would remain functional to 

maintain viability of native wildlife populations. 

Major. An action would result in detectable impacts on native wildlife, their 

habitats, or the natural processes sustaining them. Key ecosystem processes 

might be disrupted permanently. Adverse responses to disturbance by some 

individuals would be expected, with negative impacts on feeding, reproduction, 

or other factors resulting in a long-term decrease in population numbers and 

genetic variability. 

Impairment. The action would contribute substantially to the deterioration of 

special status wildlife species in the North Cascades Complex to the extent that 

they would no longer function as a natural system. In addition, some of these 
E NVIRONMENTAL C ONSEQUENCES

298 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

adverse major impacts on the North Cascades Complex’s resources and values 

would 

contribute to deterioration of special status wildlife resources and values to 

the extent that the purpose of the North Cascades Complex would not be 

fulfilled as established in its enabling legislation 

affect resources key to the natural or cultural integrity or opportunities for 

enjoyment in the North Cascades Complex 

affect the resource whose conservation is identified as a goal in the 

General Management Plan (NPS 1988b) or other planning documents for 

the North Cascades Complex 

IMPACTS OF THE ALTERNATIVES 

ON SPECIAL STATUS WILDLIFE SPECIES 

This section analyzes impacts on federally listed and state-listed species for each 

of the four alternatives. Cumulative impacts are discussed, and an overall 

summary of impacts is presented at the end of each alternative analysis. 

Some special status species that inhabit the North Cascades Complex are 

considered in this plan/EIS that are not directly linked to fish or aquatic habitats, 

such as the Canada lynx and grizzly bear. These species are included because, 

under any of the alternatives, management activities would adversely affect 

wildlife through an increased human presence and noise from fixed-wing aircraft 

and helicopters associated with lake management activities. 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A (no action) would continue existing practices in the 91 lakes slated 

for management consideration in the study area. Of these 91, 62 lakes contain 

fish today. These 62 lakes are a subset of the study area’s 91 lakes that were 

naturally fishless but have a history of fish stocking or fish presence. The 

remaining 29 lakes are currently fishless and are not actively managed for fish. 

These management activities would continue under the no-action alternative. 

The “Alternatives” chapter provides a detailed description of alternative A. For 

more information on the 91 lakes, refer to table 5 and figure 4 in the 

“Alternatives” chapter and appendix E. 

Impacts of Current Fish Stocking 

on Special Status Wildlife Species 

For impact assessment purposes, the 11 species listed below are grouped together 

because the only impacts to these species would be from incidental short-term 

noise effects from stocking activities (airplane noise or human and vehicle access 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 299

while approaching a lake). In addition, the 11 species either do not depend solely 

on lake resources or only eat fish opportunistically. 

American Peregrine Falcon  federal species of concern, state endangered 

California Wolverine  federal species of concern, state candidate

Canada Lynx  federal threatened, state threatened 

Gray Wolf  federal endangered, state endangered 

Grizzly Bear  federal threatened, state endangered 

Pacific Fisher  federal species of concern, state endangered 

Marbled Murrelet  federal threatened, state threatened 

Little Willow Flycatcher  federal species of concern 

Northern Goshawk  federal species of concern, state candidate

Northern Spotted Owl  federal threatened, state endangered 

Olive-sided Flycatcher  federal species of concern 

As discussed in the “Wildlife” section in this chapter, noise disturbance can 

result in behavioral and physiological reactions in wildlife that vary by species 

and individual (Radle 1998). Special status wildlife may experience short-term 

and temporary disturbances from stocking activities, such as interruption of 

activity or temporary flushing or fleeing, but this would not change population 

structure or function. 

Although these 11 species may be present in nearby forests, most are expected in 

very limited numbers in the North Cascades Complex and are not known to nest 

or den in the areas immediately surrounding any of the high mountain lakes in 

the study area. While an occasional passing aircraft or vehicle may cause 

temporary disturbance and/or a flight response similar to that experienced by 

other species, no other impacts stemming from fish stocking would affect them. 

Therefore, actions under alternative A may affect, but are not likely to adversely 

affect any of the above 11 species. 

The following 13 listed species are known to be present in the aquatic habitats of 

the 91 lakes or the adjacent habitats. The impacts on each species from 

alternative A are discussed below. 

Yuma Myotis (Federal Species of Concern). Yuma myotis are insect-eating 

bats that forage over high mountain lakes in the North Cascades Complex. Noise 

from stocking activities or human presence are not expected to affect the species, 

though bats may experience a minimal amount of stress when roosting during the 

day if stocking activities occur near them. Stocked fish compete for the same 

insect food base as Yuma myotis. This competition in stocked lakes is not likely 

to noticeably affect insect availability for Yuma myotis; therefore, it may be 

affected, but is unlikely to be adversely affected from actions under alternative A. 
E NVIRONMENTAL C ONSEQUENCES

300 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 301

Long-eared Bat (Federal Species of Concern). Long-eared bats glean insects 

from foliage, but also forage over water. Noise from stocking activities or human 

presence is not expected to affect long-eared bats. Similar to Yuma myotis, 

stocking activities may cause some level of stress to individuals roosting near a 

lake during stocking activities. Long-eared bats may be affected, but are unlikely 

to be adversely affected from fish stocking under alternative A. 

Bald Eagle (Federal Threatened, State Threatened). Bald eagles are a 

common winter resident along the Skagit River and can be seen in other lowelevation riparian areas of the North Cascades Complex. There is a nest near the 

head of Lake Chelan that has been active since 2001. A pair of bald eagles has 

nested at the head of Baker Lake (within 1 to 1.5 miles of the North Cascades 

Complex boundary) for many years. Alternative A may affect, but is not likely to 

adversely affect bald eagles because they only rarely, if ever, use the stocked 

mountain lakes in the North Cascades Complex to forage or roost. 

Harlequin Duck (Federal Species of Concern). Harlequin ducks are summer 

migrants that nest on the shores of larger low-gradient streams in the North 

Cascades Complex and are widely distributed in large tributaries of the Skagit 

and Stehekin rivers. They are not associated with mountain lakes, and it is 

unlikely that enough fry escape down the outlets of mountain lakes to contribute 

to their forage base. In addition, harlequin ducks primarily feed on aquatic 

invertebrates and only eat trout fry opportunistically. Impacts from alternative A 

would include a reduction in this duck’s aquatic food base as a result of stocking 

fish that may prey on invertebrate species that occur in the same drainages. Noise 

impacts would occur from stocking activities but would be short term, minor, and 

infrequent. Implementation of alternative A, may affect, but is unlikely to 

adversely affect harlequin ducks. 

Cascades Frog (Federal Species of Concern). The North Cascades Complex is 

considered the northern boundary of the Cascades frogs’ range (Bury and Adams 

2000). Predation by nonnative trout and habitat loss throughout the frog’s 

southern range is likely the reason for its federal status as a Species of Concern; 

however, the frog is not listed by the state of Washington (WDFW, D. Stinson, 

pers. comm., 2004). 

The Cascades frog primarily inhabits small pools and streams in subalpine 

meadows but also occurs in bogs, marshy areas, ponds, and small lakes. The 

Cascades frog has been documented in three locations in the North Cascades 

Complex: two ponds and a stream in Bridge Creek drainages (Bury et al. 2000). 

The distribution of these frogs in the North Cascades Complex is likely patchy, 

and they are often not found in areas that appear to have suitable habitat. 

(Leonard et al. 1993). The status of the frog and reasons for its patchy 

distribution are unknown. 

The species is not known to occupy larger, deeper lakes that contain fish, and it is 

unknown if this absence from large lakes is due to past fish predation or if the 

species naturally prefers shallower waters (Bury and Adams 2000). Because the 

species is not generally associated with lakes stocked with fish, implementation 

of alternative A may affect, but is not likely to adversely affect, Cascades frogs. 

The Harlequin duck is 

a federal species of 

concern that feeds 

primarily on aquatic 

invertebrates. 
E NVIRONMENTAL C ONSEQUENCES

302 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Columbia Spotted Frog (Federal Species of Concern, State Candidate 

Species). The Columbia spotted frog is a highly aquatic species that lives in 

mountainous areas in or near cold, slow-moving streams, springs, marshes, 

ponds, and small lakes without extensive emergent vegetation (Leonard 1993). In 

the North Cascades Complex, the Columbia spotted frog has been documented in 

wet meadows, seasonal streams, seeps, and various lakes and ponds at elevations 

ranging from 2,500 to 5,900 feet (Bury et al. 2000; Liss et al. 1995). The frog has 

been documented in these four lakes in the Stehekin River watershed: Dagger, 

McAlester, Kettling, and Coon. Two of these lakes, Dagger and McAlester, have 

reproducing populations of stocked trout. These lakes also have extensive 

meandering inlet and outlet streams that may protect the frogs from predation 

(OSU, B. Hoffman, pers. comm., 2003). Tadpoles metamorphose into adults 

during their first summer and can use temporary or shallow ponds as breeding 

sites that are inaccessible to predatory fish (Bull and Marx 2002; Pilliod and 

Peterson 2001; Llewellyn and Peterson 1998). Within the main body of lakes 

inhabited by the Columbia spotted frog, stocked trout limit the frog’s use of the 

open water areas. This may reduce the number of frogs in the lake, but does not 

extirpate Columbia spotted frogs from the surrounding wetlands and nearby 

temporary ponds, which are extensive enough to support viable breeding 

populations of the species. 

Under alternative A, Columbia spotted frogs may be affected but are not likely to 

be adversely affected in the lakes in which they have been documented. The 

number of frog larvae in the main portion of these lakes would likely be 

noticeably reduced in relation to a similar fishless lake, but populations of 

Columbia spotted frogs in the lakes that contain stocked trout would remain 

indefinitely viable in the North Cascades Complex. 

Northern Red-Legged Frog (Federal Species of Concern). Northern redlegged frogs have been documented in wetlands and ponds along the Skagit 

River near Newhalem. There is no documented presence of the species in the 

62 lakes containing stocked fish; however, not all lakes in the North Cascades 

Complex have been surveyed. Lower-elevation lakes in the Ross Lake National 

Recreation Area (Thunder, Hozomeen, Willow, and Ridley) have suitable habitat 

for northern red-legged frogs, and they have been observed in the general vicinity 

of Hozomeen village (URS, R. Nielsen, pers. comm., 2004). For this analysis, it 

is assumed that some of the 62 lakes would contain northern red-legged frogs. 

Adult northern red-legged frogs are highly terrestrial, but they are typically found 

near ponds or streams. Although adults breed in both temporary and permanent 

water sources, the breeding season is short, occurring only for one to two weeks. 

Breeding sites must have little or no flow, must last long enough for 

metamorphoses to occur before the end of summer, and must contain sturdy 

underwater stems of some sort for egg attachment (Nussbaum et al. 1983). 

Northern red-legged frogs co-evolved with trout in the coastal lowlands, and 

these behavioral mechanisms allow them to survive. Like spotted frogs, northern 

red-legged frog tadpoles are able to avoid fish predation because they 

metamorphose into adults in shallow waters (Nussbaum et al. 1983). Under 

alternative A, a number of lower-elevation lakes that would continue to have fish 

and be stocked would contain northern red-legged frog tadpoles or breeding 

adults. Nonnative trout may prey on tadpoles, but this is not likely to affect the 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 303

population of northern red-legged frogs in the North 

Cascades Complex. Therefore, northern red-legged frogs 

may be affected, but are not likely to be adversely affected 

under alternative A. The extent of impacts, nevertheless, 

would need to be verified through additional monitoring. 

Tailed Frog (Federal Species of Concern). Tadpole and 

adult tailed frogs have been documented in the outlets of six 

lakes in the North Cascades Complex (including Upper 

Bouck and Nert lakes) that are currently stocked (Liss et al. 

1995; Bury et al. 2000). Past research has shown that tailed 

frogs have evolved in stream environments with fish 

predation but are not generally found directly inhabiting 

lakes; instead, they are found in stream outlets. Stocked trout are likely to have 

minimal effects on tailed frogs in lakes (NPS, R. Glesne, pers. comm., 2003). 

The lakes do not provide primary habitat for tailed frogs, which are widely 

distributed throughout the North Cascades Complex in moderate to high-gradient 

streams; therefore, tailed frogs would incur no effect under alternative A or any 

other alternative. 

Western Toad (Federal Species of Concern, State Candidate Species).

Intensive surveys of the Big Beaver Valley in the early 1970s indicated that 

Western toads were common in a variety of habitat types, except in rockslides 

(Taber 1974). More recent amphibian surveys in North Cascades Complex found 

a fragmented distribution of adult Western toads in or near four lakes considered 

in this analysis: Battalion, Lower Thornton, Trapper, and Willow (Liss et al. 

1995). Tadpoles were observed at Trapper Lake. Western toad tadpoles and 

adults are probably not preyed upon by trout because they secrete a toxin (Corn 

1998) that is unpalatable to trout (Llewellyn and Peterson 1998; Bury and Adams 

2000; Tyler et al. 2003). For these reasons, Western toads would not be affected 

under alternative A. 

The federally listed fish species in the North Cascades Complex inhabit rivers 

downstream from the high mountain lakes addressed in this plan/EIS. The level 

of effect on these downstream fish communities would be expected to vary 

depending on several factors: whether there is a connection from the lake to a 

downstream basin (an outlet); the species of trout stocked; the extent of 

reproduction in a lake; and the species of native fish in the downstream 

watershed. Impacts were assessed using the same predictive factors identified for 

impacts to nonlisted native fish as a guidance and considering the evidence of 

colonization and/or hybridization reported for these species (WDFW, 

M. Downen, pers. comm., 2004). A more detailed evaluation for each of the 

listed fish species is provided below. 

Bull Trout (Federal Threatened, State Candidate). Bull trout are found in the 

Chilliwack, Skagit, and Ross drainage basins on the west side of the Cascade 

Crest, and juveniles are found in the higher stream reaches. Bull trout were once 

found on the east side of the crest; however, they have been extirpated from those 

drainages, and the NPS and other agencies are interested in restoration. Bull trout 

on the west side of the Cascade Crest are at risk from hybridization and/or 

competition from introduced fish in upstream lakes that are connected to the 

Nert Lake (shown 

above), along with 

Upper Bouck, are 

two of six lakes 

with documented 

populations of 

tailed frogs. 
E NVIRONMENTAL C ONSEQUENCES

304 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

west-side drainages. In addition, fish that might enter downstream drainages may 

also enter the forage base for bull trout. 

The lower Skagit River harbors one of the most robust populations of bull trout 

in the western United States. WDFW estimates (based on available habitat, 

spawning surveys, and fishery interceptions rates) range from 10,000 to 15,000 

migratory adults. Strong populations (greater than 100 spawning individuals 

annually) in the Skagit core area occur in every major sub-basin of the Skagit 

including the Baker, Sauk, Whitechuck, Suiattle, Cascade, and mainstem. 

Consequently, the Skagit is one of only two river systems where a recreational 

fishery is still managed, allowing the retention of two fish per day over 20 inches 

(WDFW, M. Downen, pers. comm., 2004). 

The major tributaries in the North Cascades Complex that are used by bull trout 

for spawning below the Seattle City Light projects include Bacon Creek, Goodell 

Creek, Marble Creek, and the South Fork of the Cascade. The populations in 

Bacon and Goodell creeks are part of WDFW’s long-term monitoring program, 

and both Marble and the South Fork of the Cascade are sampled periodically. 

Bacon, Goodell, and Marble creeks all support populations of over 100 spawning 

adults, and the South Fork of the Cascade supports more than 500 spawning 

adults. Other lesser tributaries such as Thornton, Damnation, Day, Lookout, and 

Sibley are not spawning tributaries but are frequented by sub-adult and adult fish 

in search of foraging opportunities (WDFW, M. Downen, pers. comm., 2004). 

Bull trout probably colonized the upper Skagit Basin above the Seattle City Light 

projects shortly after the last glacial recession and are now considered a separate 

population from the lower Skagit. In the Ross basin, which is part of the larger 

upper Skagit core population, bull trout show a life history analogous to the 

anadromous life history shown in the lower Skagit. Major spawning tributaries 

within the North Cascades Complex boundary include Ruby, Big Beaver, 

Lightning, Silver, and Little Beaver creeks (WDFW, M. Downen, pers. comm., 

2004). 

Both brook trout and nonnative westslope cutthroat trout present potential threats 

to bull trout in west-side drainages connected to lakes containing these species. 

The primary concern is the potential for hybridization with introduced brook 

trout, which would affect the reproductive success of the bull trout population. 

Brook trout occur in three west-side lakes within the Baker and Ross drainage 

basins: Hozomeen, Blum (Lower West No. 4), and Sourdough. The potential for 

hybridization between the bull trout and brook trout is of particular concern in 

Hozomeen Creek in the Ross watershed, but hybridization has not yet been 

documented (WDFW, M. Downen, pers. comm., 2004). The lack of 

hybridization may be related to differences in spawning habitat because brook 

trout tend to spawn in warmer water, while bull trout spawn in very cold water. 

Potential impacts on bull trout would also result from competition for resources 

and predation on juvenile bull trout inhabiting upper stream reaches if either 

westslope cutthroat or brook trout are stocked in west-side lakes. The nonnative, 

more mature resident fish would disperse to downstream drainages and prey 

upon juvenile char. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 305

There are currently 21 west-side lakes (see table G-5 in appendix G) containing 

brook or westslope cutthroat trout that have outlets to drainages with bull trout 

populations, but not all drain to spawning tributaries (WDFW, M. Downen, pers. 

comm., 2004). In addition, studies in Montana and other regions where westslope 

cutthroat co-occur suggest the two species co-exist, although some competition 

has been observed. Overall, the extent of the impacts from competition and 

predation is likely minor, although more data would be required to more 

accurately assess this impact. 

In summary, the potential impacts on bull trout from westslope cutthroat trout are 

likely minor and related mainly to competition for resources. The impacts on bull 

trout from introduced brook trout would be more serious if colonization and 

hybridization would occur, but information from WDFW about the four lakes 

containing brook trout indicate this has not occurred in the downstream 

drainages; therefore, alternative A may affect, but is not likely to adversely 

affect, bull trout. 

Chinook Salmon (Federal Threatened). Chinook (king) salmon occur in the 

lower reaches of the Skagit River and its major tributaries and in the mainstem of 

the Baker River. Hybridization with nonnative fish is not known to occur, and 

attempted hybridization between Chinook and nonnative species has not been 

successful. There is a slight possibility that if mature stocked fish migrate from 

lakes to downstream drainages containing Chinook salmon, they may affect 

Chinook salmon through competition. This effect, though, is questionable given 

their vastly different life histories. Also, predation is unlikely because westslope 

cutthroat trout generally do not consume young fish but rather feed on aquatic 

and terrestrial insects. 

Currently, there are reproducing westslope cutthroat trout in 13 lakes in the 

Skagit basin and reproducing brook trout in 1 lake in the Baker drainage basin 

(see table G-5 in appendix G). Considering the fact these fish would not likely 

colonize as far downstream as Chinook are found, and the lack of hybridization 

and predation potentials, alternative A may affect, but is not likely to adversely 

affect Chinook salmon. 

Coho Salmon (Federal Candidate Species, State Candidate Species). The 

Georgia Strait/Puget Sound Evolutionarily Significant Unit (ESU) of Coho 

salmon inhabits the Skagit, Baker, and Chilliwack rivers and their higher-order, 

lower-gradient tributaries. Coho salmon spend their first year in the birth 

tributary and the next 18 months in the ocean before returning to spawn from 

November through early February. Because the young spend roughly one year in 

freshwater before smolting (when young salmon swim to the ocean), they must 

compete with other native salmonids and potentially with introduced fish 

dispersing downstream. Hybridization with nonnative fish does not occur. 

Reproducing westslope cutthroat trout are currently in 15 lakes in the Skagit 

Basin, and reproducing brook trout are in 1 lake in the Baker drainage basin and 

2 lakes in the Ross drainage basin (see table G-5 in appendix G). Impacts on 

Coho salmon would be limited because of the lack of potential for hybridization 

or predation by westslope cutthroat trout, as described above for Chinook 
E NVIRONMENTAL C ONSEQUENCES

306 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

salmon; therefore, alternative A may affect, but is unlikely to adversely affect 

Coho salmon. 

Westslope Cutthroat Trout (Federal Species of Concern). Westslope (inland) 

cutthroat trout are native to the Stehekin River and its tributaries on the east side 

of the Cascade Crest, though the species was introduced to stream basins on the 

west side of the Cascade Crest, where it is considered a threat to west-side native 

fish. Within the westslope cutthroat trout’s native range on the east side, 

introduced stocks of rainbow trout in Lake Chelan and various other lakes at the 

headwaters of the Stehekin River have replaced some native populations of 

westslope cutthroat trout through either competition between the species or 

hybridization (Behnke 1992). Recent genetic research has demonstrated that 

rainbow trout dispersing downstream from stocked mountain lakes in the 

Stehekin drainage are responsible for some of the hybridization (WFRC, 

C. Ostberg, pers. comm., 2004). There are two genetically “pure” strains of 

westslope cutthroat still present in the headwaters of the Stehekin River drainage 

and in Park Creek, Flat Creek, and likely, Bridge Creek. The persistence of these 

two pure strains may be related to water temperature because rainbow trout do 

not appear to be able to spawn in the colder waters of the Stehekin drainage 

(WFRC, C. Ostberg, pers. comm., 2004). 

Under alternative A, nine lakes in the Stehekin basin with stream outlets have 

reproducing rainbow or rainbow/cutthroat hybrid trout that would adversely 

impact native westslope cutthroat trout inhabiting downstream drainages. 

Documentation of colonization and hybridization has been confirmed in one 

downstream drainage (outlet to McAlester Lake). Based on the evidence, native 

westslope cutthroat trout may be affected and are likely to be adversely affected 

in at least one lake through hybridization by introduced rainbow/cutthroat trout 

under alternative A. 

State-Listed Wildlife Species. Under alternative A, six species listed at the state 

level (black-backed woodpecker, golden eagle, Lewis’ woodpecker, merlin, 

pileated woodpecker, and Vaux’s swift) would experience negligible to minor 

adverse impacts from fish stocking or associated activities. Noise impacts from 

aircraft stocking or human presence may temporarily flush one of these state 

candidate species, as previously described for several federally listed species, but 

would not result in any detrimental effects to populations. 

The common loon (Washington State sensitive species) would incur negligible 

adverse impacts. Continuation of fish stocking would provide beneficial effects 

by supporting an adequate food base for nesting common loons near Hozomeen 

Lake or other stocked lakes. 

Cumulative Impacts 

Cumulative impacts on special status species are considered for past, present, and 

future projects occurring in the North Cascades Complex or on lands outside the 

North Cascades Complex boundary. No new major roads, trails, resorts, or major 

upgrades of facilities are proposed or in the planning stages. Some access had 

been eliminated or reduced due to flooding of trails. Visitor use is expected to 

remain at about the same levels it has been for several years, resulting in about 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 307

the same level of human presence near most lakes and connected streams. 

Human recreational use of the lakes and surrounding drainages may cause 

adverse impacts on special status species in the North Cascades Complex due to 

noise and disturbance associated with human presence. However, some of this 

disturbance to listed species from backpackers, campers, and anglers would be 

mitigated by the natural topography of the landscape (which can provide sound 

or visual buffering) and the forested areas that provide refuge for wildlife. In 

addition, sport and commercial fishing may also result in direct adverse impacts 

on salmon populations in the Pacific Northwest. 

Mountain lake fisheries on National Forest System lands that surround the North 

Cascades Complex are managed by the WDFW. The department’s management 

history is described in WDFW (2001), and management would continue to 

evolve with continued interest in the stocking of native species. Lakes stocked in 

the past are assumed to have a range of impacts on special status species similar 

to what has been analyzed for the North Cascades Complex lakes, which varies 

from no effect, to may affect, to likely to adversely affect, depending on the 

species. On a landscape scale, the piscivorous species generally benefit from the 

presence of stocked fish in mountain lakes where resources were previously 

lacking. Because stocking has occurred in previously fishless lakes, fish-eating 

species, such as ospreys, have expanded their territories and home ranges, which 

benefits individuals. However, ecologically speaking, introduction of nonnative 

species is considered detrimental to community dynamics of a listed species. A 

species already considered threatened or endangered due to its rarity would 

potentially face an increasing threat of local extirpation through nonnative 

species competition, predation, or hybridization. Continued presence of fish in 

North Cascades Complex lakes, coupled with continued presence of fish in lakes 

on surrounding lands, would tend to make piscivorous species more widespread 

and increase their populations. 

There would be continued, localized, and sporadic effects on special status 

wildlife species from logging and water projects occurring outside the North 

Cascades Complex, including in connected watersheds. These actions can cause 

severe habitat loss for many species of plants and animals, particularly, listed 

salmon species that are unable to return to spawning habitat. Logging along the 

Pacific Coast has caused siltation and reduced shade cover, resulting in increased 

stream temperature to lethal levels for the juveniles and eggs to survive. 

Other sources of impacts continue to occur that may affect the health and 

viability of species dependent on aquatic resources. There is concern about 

persistent organic pollutants and methyl-mercury found in some lakes in the 

North Cascades Complex, which appear to result from airborne pollutants being 

deposited on snow and washed into lakes. There is the potential for increased 

acid rain from emissions related to the development of an additional power plant 

in the area; emissions would contribute to an increase in lake acidity and metal 

availability. In some cases, the concentrations of some of these pollutants in the 

water in preliminary studies appear to be high enough to raise concerns that, in 

conjunction with other influences, higher trophic-level organisms may be 

affected. Toxins can be passed from the tissue of one organism to those that feed 

on it, meaning that a toxin can move up the food chain and bioaccumulate to 

higher concentrations in the top predators, such as bald eagles, to the point where 
E NVIRONMENTAL C ONSEQUENCES

308 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

they cause reproductive failure. If that occurred, then the cumulative impacts of 

the pollutants coupled with other impacts, perhaps from fish, might eliminate that 

predator species from certain lakes or even cause a more general decline in the 

population. 

Alternative A, combined with other actions in the area, may affect, and is likely 

to adversely affect special status species in the study area on a cumulative basis, 

especially special status amphibians and fish. The actions under alternative A, 

however, only add small incremental impacts to the potential overall impacts on 

listed species and affect one species of native fish (westslope cutthroat trout). 

Also, an accurate determination of the magnitude of cumulative impacts on each 

special status species cannot be made because available information and research 

on each species’ biology, status, and distribution is insufficient. Additional 

research and population monitoring of special status species that would be 

affected by the alternatives in this plan/EIS, combined with research completed 

in the region, would help to better determine cumulative impacts. 

Conclusion 

Based on available information, fixed-wing aircraft noise and human disturbance 

associated with periodic fish stocking activities under alternative A would have a 

range of short-term negligible to minor effects on special status wildlife species. 

Fish removal does not occur under alternative A, so there would be no impacts 

on special status wildlife species from lake treatments to remove fish. 

Based on the available information, alternative A would have no adverse effects 

on federally listed species from fish stocking. Regarding federally listed species:

21 species may be affected but are not likely to be adversely affected

(American peregrine falcon, California wolverine, Canada lynx, gray wolf, 

grizzly bear, marbled murrelet, Northern goshawk, Northern spotted owl, 

Pacific fisher, Yuma myotis, long-eared bat, bald eagle, harlequin duck, 

little willow flycatcher, olive-sided flycatcher, Cascades frog, Columbia 

spotted frog, northern red-legged frog, bull trout, Chinook salmon, Coho 

salmon). 

2 species would incur no effect (tailed frog and Western toad). 

1 species may be affected and is likely to be adversely affected

(westslope cutthroat trout)—effects would be limited to one drainage 

downstream from McAlester Lake as a result of documented hybridization 

and colonization. 

Regarding state-listed species that are not federally listed, 6 species would incur 

short-term negligible to minor adverse impacts (solely from noise related to 

stocking activities), and the common loon would incur short-term negligible 

adverse impacts. Continuation of stocking would provide beneficial effects by 

supporting an adequate food base for nesting loons near Hozomeen Lake and 

other stocked lakes. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 309

Cumulative impacts on each special status species from projects or actions 

occurring throughout the region would be adverse; however, alternative A would 

contribute only a small increment to overall cumulative impacts. 

Impairment of special status wildlife species across the study area would not 

occur under alternative A. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative would be to eliminate or reduce reproducing fish 

from lakes in the study area (refer to tables 4 and 5 in the “Alternatives” chapter). 

Restocking of nonreproducing fish would be allowed only where biological 

resources would be protected. Based on best available science, some lakes would 

be restocked with nonreproducing fish at low densities once reproducing fish 

have been removed. An extensive monitoring program (see appendix F), which 

includes adaptive management provisions, would be implemented to avoid 

unacceptable future effects on native biota. 

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed Fish Stocking 

and Lake Treatment Methods 

on Special Status Wildlife Species 

Similar to alternative A, alternative B may affect, but is not likely to adversely 

affect, any of the 11 species listed below that either do not depend on lake 

resources or only eat fish opportunistically, or they would not be disturbed by 

activities associated with fish stocking or lake treatments to remove fish. 

American Peregrine Falcon  federal species of concern, state candidate 

California Wolverine  federal species of concern, state threatened 

Canada Lynx  federal threatened, state threatened 

Gray Wolf  federal endangered, state endangered 

Grizzly Bear  federal threatened, state endangered 

Pacific Fisher  federal species of concern, state endangered 

Marbled Murrelet  federal threatened, state threatened 

Little Willow Flycatcher  federal species of concern 
E NVIRONMENTAL C ONSEQUENCES

310 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Both of the lakes 

pictured below have 

a high density 

of reproducing fish.

Blum Lake–Largest/Middle No. 3 

Blum Lake–Lower/West No. 4 

Blum Lake–Largest/Middle No. 3 

Northern Goshawk  federal species of concern, state candidate 

Northern Spotted Owl  federal threatened, state endangered 

Olive-sided Flycatcher  federal species of concern 

The following 13 listed species are known to be present in the 

aquatic habitats of the 91 lakes or the adjacent habitats. The 

impacts on each species from alternative B are discussed below. 

Yuma Myotis (Federal Species of Concern). Similar to 

alternative A, Yuma myotis may be affected, but are unlikely to be 

adversely affected from actions under alternative B. Yuma myotis 

bats may experience a minimal amount of stress if stocking or 

treatment activities occur near a diurnal (daytime) roost. 

Competition for insects with fish in stocked lakes is not likely to 

noticeably affect insect availability for Yuma myotis. 

Long-eared Myotis (Federal Species of Concern). Similar to 

alternative A, long-eared myotis may be affected but are unlikely 

to be adversely affected from actions under alternative B. Longeared bats may experience minor stress if stocking or treatment 

activities occur near a diurnal (daytime) roost. Competition for 

insects with fish in stocked lakes is unlikely to affect insect 

availability for long-eared myotis. 

Bald Eagle (Federal Threatened, State Threatened). Similar to 

alternative A, alternative B may affect, but is not likely to 

adversely affect, bald eagles because they only rarely, if ever, use 

the high-elevation stocked lakes in the North Cascades Complex 

to forage or roost. 

Harlequin Duck (Federal Species of Concern). Similar to 

alternative A, implementation of alternative B, may affect, but is unlikely to 

adversely affect, harlequin ducks because implementation of alternative B would 

potentially reduce the aquatic food base for the species due to competition with 

introduced trout. In addition, noise impacts would occur from stocking activities 

but would be short term, minor, and infrequent. 

Cascades Frog (Federal Species of Concern). The status and distribution of 

Cascades frogs in the North Cascades Complex is generally unknown, but the 

species has been documented in two ponds and one stream location in the Bridge 

Creek drainage (Bury et al. 2000). Because the species is not generally associated 

with lakes stocked with fish, implementation of alternative B, may affect, but is 

not likely to be adversely affect Cascades frogs. Removal of fish in high 

mountain lakes may serve to benefit Cascades frogs if their absence in larger, 

deeper lakes was due to past predation by nonnative fish. 

Columbia Spotted Frog (Federal Species of Concern, State Candidate 

Species). Under alternative B, one of the lakes containing Columbia spotted 

frogs (Kettling Lake) would be chemically treated to become fishless. Two lakes, 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 311

Dagger and McAlester, would be chemically treated to remove all reproducing 

fish. The lakes would be evaluated to determine if restocking is advisable, and 

these lakes would be stocked with nonreproducing fish at low densities. Coon 

Lake would continue to be stocked at low densities under alternative B. These 

three lakes (Dagger, McAlester, and Coon) have extensive meandering inlet and 

outlet streams that may protect the frogs from fish predation (OSU, Hoffman, 

pers. comm., 2003). Within the main body of lakes inhabited by the Columbia 

spotted frog, stocked fish likely limit frog use. This may reduce the number of 

frogs in the lake, but it would not eliminate spotted frogs from the surrounding 

wetlands and nearby temporary ponds, which are extensive enough to support 

viable breeding populations of the species. 

Under alternative B, Columbia spotted frogs may be affected but are not likely to 

be adversely affected in the lakes where stocking would continue. The number of 

frog larvae in the main portion of stocked lakes would likely be noticeably 

reduced in relation to a similar fishless lake. Populations of Columbia spotted 

frogs in the lakes that contain stocked trout would remain viable in the North 

Cascades Complex indefinitely. Also, populations of frogs in lakes that would 

become fishless under alternative B would not incur further impacts from fish 

predation. Moreover, the reduction in fish density and the elimination of fish 

would be a beneficial effect to the frogs. 

Chemical treatment with antimycin to remove fish in Kettling, Dagger, 

McAlester, and Coon lakes may affect, but is unlikely to adversely affect, 

Columbia spotted frogs. As discussed in the “Aquatic Organisms” section in this 

chapter, the use of antimycin is not known to have adverse impacts on 

amphibians. Impacts on northern Columbia spotted frogs from trampling would 

be mitigated to the greatest extent possible, as described in appendix I. 

Northern Red-Legged Frog (Federal Species of Concern). As described in 

alternative A, Northern red-legged frogs have been documented in wetlands and 

ponds along the Skagit River near Newhalem and in the Big Beaver valley but 

have not been confirmed in the 62 lakes in the study area that currently contain 

fish because surveys have not been completed. Lower-elevation lakes in the Ross 

Lake National Recreation Area (Thunder, Hozomeen, Willow, and Ridley) have 

suitable habitat for the species and would contain northern red-legged frogs. 

Under alternative B, maintaining Thunder Lake as fishless and chemically 

removing fish from Hozomeen Lake would result in long-term beneficial effects 

to any red-legged frogs present in these lakes. As discussed in the “Aquatic 

Organisms” section in this chapter, the use of antimycin may have short-term 

adverse impacts on amphibians. Impacts on northern red-legged frogs from 

trampling or other disturbance related to lake treatment would be mitigated to the 

greatest extent possible, as described in the appendix I. If northern red-legged 

frogs are found to occur in Willow or Ridley lakes, nonnative fish may prey on 

northern red-legged frog tadpoles. The species may be affected, but are not likely 

to be adversely affected, by stocked fish in those lakes. Adverse impacts from 

nonnative fish are not likely to affect the population of northern red-legged frogs 

in the North Cascades Complex. The extent of the impacts would need to be 

verified through monitoring. 
E NVIRONMENTAL C ONSEQUENCES

312 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Tailed Frog (Federal Species of Concern). Tadpole and adult tailed frogs have 

been documented in the outlets of six lakes in the North Cascades Complex, 

including Upper Bouck and Nert lakes (Liss et al. 1995; Bury et al. 2000), which 

are currently stocked. The lakes would no longer be stocked under alternative B 

and would eventually become fishless. Some populations of tailed frogs have 

evolved in stream environments with fish predation (NPS, R. Glesne, pers. 

comm., 2003). In the North Cascades Complex, many populations are found in 

high-gradient tributaries that are inaccessible to fish. Under alternative B, threats 

to tailed frogs from predatory fish would cease. Removal of fish in Upper Bouck 

and Nert lakes would occur simply through discontinued stocking, and therefore, 

alternative B would have no effect on tailed frogs in the North Cascades 

Complex. 

Western Toad (Federal Species of Concern, State Candidate Species). Recent 

amphibian surveys in North Cascades Complex found a fragmented distribution 

of adult Western toads in or near four lakes considered in this analysis: Battalion, 

Lower Thornton, Trapper, and Willow (Liss et al. 1995). Tadpoles were observed 

at Trapper Lake. Battalion Lake would be treated to remove all fish and then 

monitored to evaluate for restocking after additional data is gathered. Dagger 

Lake would be evaluated to determine if fish removal is feasible; if not, then fish 

density would be reduced. The remaining lakes would continue to be stocked at 

low densities. Western toad tadpoles and adults are probably not preyed upon by 

trout because they secrete a toxin (Corn 1998) that is unpalatable to trout 

(Llewellyn and Peterson 1998; Bury and Adams 2000; Tyler et al. 2003). For 

these reasons, Western toads would not be affected under alternative B. Fish in 

Battalion Lake would be removed using chemical treatment methods, and as 

discussed in the “Aquatic Organisms” section in this chapter, the use of 

antimycin is not known to have adverse impacts on amphibians. Impacts on 

Western toads from trampling during lake treatments would be mitigated to the 

greatest extent possible, as described in appendix I. Based on potential minor 

disturbance from lake treatment activities, Western toads may be affected, but are 

unlikely to be adversely affected by actions under alternative B. 

Bull Trout (Federal Threatened, State Candidate). Under alternative B, the 

potential for future adverse impacts on bull trout would be reduced compared to 

alternative A, and there would be a long-term beneficial effect on the species 

from removal of fish and reduction in fish densities. Of particular benefit to bull 

trout would be the eventual removal of brook trout from Hozomeen and 

Sourdough lakes, reducing the possibility of hybridization between bull and 

brook trout. Two lakes (Lower Thornton and Firn) would continue to contain 

nonnative westslope cutthroat trout; however, Lower Thornton does not drain to 

bull trout spawning tributaries where competition would be an issue. Cutthroat in 

Thornton Creek would probably provide sub-adult bull trout with a foraging 

opportunity. Moreover, there is currently no evidence of widespread distribution 

of westslope cutthroat in the Skagit River. To the contrary, snorkeling surveys 

only note occasional occurrence of individuals of the species. It is unlikely that 

the few low-density westslope trout in these lakes would adversely affect bull 

trout; therefore, actions in alternative B may affect, but are not likely to adversely 

affect, bull trout. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 313

Chinook Salmon (Federal Threatened). Under alternative B, 24 lakes in the 

Baker and Skagit basins would be treated to remove fish or decrease fish 

densities (refer to table G-5 in appendix G), and the potential for adverse impacts 

on Chinook salmon would eventually be eliminated in these basins. These actions 

would have long-term beneficial effects on Chinook salmon. One lake in the 

Skagit basin (Lower Thornton) would continue to have reproducing westslope 

cutthroat trout, but this would not cause impacts on native Chinook salmon in 

that basin from competition and predation, as explained under alternative A. 

Chinook salmon are not likely to be in upstream reaches near the lake, and the 

fish density would be maintained at low levels; therefore, alternative B may 

affect, but is not likely to adversely affect, Chinook salmon in the study area. 

Coho Salmon (Federal Candidate Species, State Candidate Species). Under 

alternative B, 26 lakes in the Baker, Skagit, and Chilliwack basins would be 

treated to remove fish or decrease fish densities, and the potential for adverse 

impacts on Coho salmon would eventually be eliminated in these basins (refer to 

table G-5 in appendix G). This reduction in density and elimination of fish would 

have long-term beneficial effects to Coho salmon. One lake in the Skagit basin 

(Lower Thornton) would continue to have reproducing westslope cutthroat trout, 

which would not cause impacts on native Coho salmon in that basin from 

competition and predation, as explained under alternative A. Alternative B may 

affect, but is not likely to adversely affect Coho salmon in the study area. 

Westslope Cutthroat Trout (Federal Species of Concern). Under 

alternative B, reproducing populations of rainbow cutthroat hybrid trout would 

be removed from McAlester Lake, where evidence of downstream colonization 

and hybridization has been confirmed. Westslope cutthroat trout in downstream 

drainages would incur long-term beneficial effects from the elimination of 

nonnative reproducing fish in this lake. Actions under alternative B, may affect, 

but are not likely to adversely affect westslope cutthroat trout in its native range, 

although it is recognized that until all reproducing nonnative fish are removed 

from McAlester Lake, the potential for continued hybridization with westslope 

cutthroat trout would exist. 

State Listed and Other Special Status Wildlife Species. Under alternative B, 

six species (black-backed woodpecker, golden eagle, Lewis’ woodpecker, merlin, 

pileated woodpecker, and Vaux’s swift) may incur minor impacts from fish 

stocking and lake treatment activities. Noise impacts from fixed-wing aircraft, 

helicopters, or human presence may temporarily flush individuals of these state 

candidate species if present near a lake when stocking or treatment activities are 

occurring, but this would not result in any detrimental impacts on these wildlife 

species. 

The common loon (Washington State sensitive species) would be adversely 

affected by actions under alternative B because stocked fish would be removed 

from Hozomeen Lake. This may result in minor to moderate impacts on the pair 

of breeding loons that has nested at Hozomeen Lake since at least 1971. 

Adequate fish resources to support a family of loons may exist in nearby Ross, 

Ridley, and Willow lakes. Loons are declining in Washington due to the loss of 

low-elevation lake habitats and associated human disturbances (Richardson et al. 

2000). While the loss of habitat at Hozomeen Lake is unlikely to affect the 
E NVIRONMENTAL C ONSEQUENCES

314 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

overall population of common loons, at the local level, the breeding pair of loons 

would be displaced from Hozomeen Lake and either would choose an adjacent 

area to nest or would stop nesting in the North Cascades Complex. Therefore, 

common loons would incur minor to moderate adverse impacts under 

alternative B. 

Cumulative Impacts 

Under alternative B, cumulative impacts on special status species would be 

similar to those described for alternative A. There would, however, be a 

reduction of impacts on native fish in several drainages and on amphibians due to 

the eventual removal of fish in 20 lakes and replacement of high-density 

reproducing fish with lower-density nonreproducing fish in others. 

Overall, the impacts associated with other projects, uses, and actions occurring in 

the region (as described under alternative A), added to the impacts predicted 

under alternative B, may affect, and are likely to adversely affect certain special 

status species in the region on a cumulative basis. However, the actions under 

alternative B add only small incremental impacts to the potential overall impacts 

on listed species, and only for one species of native fish (westslope cutthroat 

trout). Also, an accurate determination of the magnitude of cumulative impacts 

on special status species cannot be made because available information and 

research on species’ biology, status, and distribution is insufficient. Additional 

research and population monitoring of special status species that would be 

affected by this plan/EIS, combined with research completed in the region, would 

help to better determine cumulative impacts. 

Conclusion 

Fixed-wing aircraft noise and human disturbance associated with periodic fishstocking activities under alternative B would have a range of short-term 

negligible to minor effects on some special status wildlife species but would be 

reduced from the effects that would occur under alternative A. Short-term 

impacts related to lake treatments to remove fish would be minor, mostly due to 

noise from helicopters transporting lake treatment equipment and human 

disturbance during treatment activities. The use of the chemical, antimycin, to 

remove fish is not known to have adverse impacts on amphibians. There would 

be long-term beneficial effects on some aquatic species because most highdensity reproducing populations of fish would be replaced with low-density 

nonreproducing stocked fish. 

Based on the available information, alternative B would have no adverse effects 

on federally listed species from fish stocking or lake treatments to remove fish. 

Regarding federally listed species:

23 species may be affected but are not likely to be adversely affected

(American peregrine falcon, California wolverine, Canada lynx, gray wolf, 

grizzly bear, little willow flycatcher, marbled murrelet, Northern goshawk, 

Northern spotted owl, olive-sided flycatcher, Pacific fisher, Yuma myotis, 

long-eared bat, bald eagle, harlequin duck, Cascades frog, Columbia 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 315

spotted frog, northern red-legged frog, Western toad, bull trout, Chinook 

salmon, Coho salmon, westslope cutthroat trout). 

1 species would incur no effect (tailed frog). 

Regarding state-listed species that are not federally listed, 6 species would incur 

short-term negligible to minor adverse impacts from noise related to stocking and 

lake treatment activities, and the common loon would incur long-term minor to 

moderate adverse impacts due to the removal of its primary food source from 

Hozomeen Lake. 

Cumulative impacts on each special status species from projects or actions 

occurring throughout the region would be adverse; however, alternative B would 

contribute only a small increment to overall cumulative impacts. 

Impairment of special status wildlife species across the study area would not 

occur under alternative B. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

The goal of this alternative is to eliminate all fish in lakes in the national park and 

reduce or eliminate reproducing fish in the Lake Chelan and Ross Lake National 

Recreation Areas, but still allow for some sport fishing in the two recreation 

areas. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Impacts from Proposed Fish Stocking 

and Lake Treatment Methods 

on Special Status Wildlife Species 

Similar to alternatives A and B, alternative C may affect, but is not likely to 

adversely affect, any of the following 11 species because they either do not 

depend on lake resources or only eat fish opportunistically, or would not be 

disturbed by activities associated with fish stocking or lake treatments to remove 

fish. 

American Peregrine Falcon  federal species of concern, state endangered 

California Wolverine  federal species of concern, state candidate 

Canada Lynx  federal threatened, state threatened 

Gray Wolf  federal endangered, state endangered 

Grizzly Bear  federal threatened, state endangered 
E NVIRONMENTAL C ONSEQUENCES

316 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Pacific Fisher  federal species of concern, state endangered 

Marbled Murrelet  federal threatened, state threatened 

Little Willow Flycatcher  federal species of concern 

Northern Goshawk  federal species of concern, state candidate 

Northern Spotted Owl  federal threatened, state endangered 

Olive-sided Flycatcher  federal species of concern 

The following 13 listed species are known to be present in the aquatic habitats of 

the 91 lakes or the adjacent habitats. The impacts on each species from 

alternative C are discussed below. 

Yuma Myotis (Federal Species of Concern). Yuma myotis may be affected, but 

are unlikely to be adversely affected from actions under alternative C. Yuma 

myotis bats may experience a minimal amount of stress when roosting during the 

day if stocking or treatment activities occur near a roost. 

Long-eared Myotis (Federal Species of Concern). Long-eared myotis may be 

affected but are unlikely to be adversely affected from actions under 

alternative C. The species may experience a minor stress if stocking or treatment 

activities occur near a roost. 

Bald Eagle (Federal Threatened). Similar to alternative A, alternative C may 

affect but is not likely to adversely affect bald eagles because they only rarely, if 

ever, use the high-elevation stocked lakes in the North Cascades Complex to 

forage or roost. 

Harlequin Duck (Federal Species Of Concern). Similar to alternative A, 

implementation of alternative C, may affect, but is unlikely to adversely affect 

harlequin ducks, as implementation of alternative C may result in a slight 

reduction in the availability of invertebrates due to competition with introduced 

trout. In addition, noise impacts would occur from stocking activities, but would 

be short term, minor, and infrequent. 

Cascades Frog (Federal Species of Concern). In the North Cascades Complex, 

the Cascades frog has been documented in two ponds and one stream location in 

the Bridge Creek drainage (Bury et al. 2000). The species seems to be absent 

from lakes stocked with fish; however, it is unknown if this is due to predation 

from stocked trout or a preference for shallower waters. For these reasons, 

implementation of alternative C, may affect, but is not likely to adversely affect, 

Cascades frogs. Removal of fish in some high mountain lakes under alternative C 

would provide an overall benefit for Cascades frogs if their absence in larger, 

deeper lakes was due to past predation by nonnative fish. 

Columbia Spotted Frog (Federal Species of Concern, State Candidate 

Species). Under alternative C, Coon Lake, which contains Columbia spotted 

frogs, would continue to be stocked with low densities of fish, while chemical 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 317

treatment methods would be used to remove fish in Kettling and Dagger lakes. 

McAlester would be chemically treated to remove all reproducing fish and would 

then be evaluated to determine if restocking is advisable, so there may be fish 

stocked again in this lake but at low densities. Impacts on Columbia spotted frogs 

in these lakes would be similar to those described for the species under 

alternative B, and long-term benefits would occur from the removal of fish in 

other mountain lakes. Under alternative C, Columbia spotted frogs may be 

affected but are not likely to be adversely affected, by stocking or treatment 

activities. 

Northern Red-Legged Frog (Federal Species of Concern). Under 

alternative C, Hozomeen Lake would be chemically treated to remove fish, while 

Willow and Ridley lakes would continue to be stocked at low densities. Because 

fish would remain in Willow and Ridley lakes, Northern red-legged frogs may be 

affected, but are not likely to be adversely affected, by stocked fish under 

alternative C, similar to impacts described in alternative B. Northern red-legged 

frogs would experience long-term beneficial effects from removal or reduction of 

fish in other lakes, and the extent of adverse impacts would need to be verified 

through monitoring. 

Tailed Frog (Federal Species of Concern). Tadpole and adult tailed frogs have 

been documented in the outlets of six lakes in the North Cascades Complex, 

including Upper Bouck and Nert lakes (Liss et al. 1995; Bury et al. 2000), which 

are currently stocked. The lakes would no longer be stocked under alternative C 

and would eventually become fishless. Some populations of tailed frogs have 

evolved in stream environments with fish predation (NPS, R. Glesne, pers. com., 

2003). In the North Cascades Complex, many populations are found in highgradient tributaries that are inaccessible to fish. Under alternative C, threats to 

tailed frogs from predatory fish would cease. Removal of fish in Upper Bouck 

and Nert lakes would occur simply through discontinued stocking, and therefore, 

alternative C would have no impact on tailed frogs in the North Cascades 

Complex. 

Western Toad (Federal Species of Concern, State Candidate Species). Recent 

amphibian surveys in North Cascades Complex found a fragmented distribution 

of adult Western toads in or near four lakes considered in this analysis: Battalion, 

Lower Thornton, Trapper, and Willow (Liss et al. 1995). Tadpoles were observed 

at Trapper Lake. Battalion Lake would be treated to remove all fish and then 

monitored to evaluate for restocking after additional data is gathered. Lower 

Thornton Lake would become fishless under alternative C, and Willow Lake 

would continue to be stocked at low densities. If feasible, fish would be removed 

from Trapper Lake. Western toad tadpoles and adults are probably not preyed 

upon by trout because they secrete a toxin (Corn 1998) that is unpalatable to trout 

(Llewellyn and Peterson 1998; Bury and Adams 2000; Tyler et al. 2003). For 

these reasons, Western toads would not be affected under alternative C. Impacts 

on Western toads from continued stocking activities or lake treatment would be 

similar to those discussed in alternative B and be limited to very localized 

disturbances from human presence and habitat trampling. Western toads may be 

affected, but are unlikely to be adversely affected, by actions under alternative C; 

nevertheless, long-term beneficial impacts on western toads would result from 

removal or reduction of fish in these lakes. 
E NVIRONMENTAL C ONSEQUENCES

318 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Bull Trout (Federal Threatened). Under alternative C, all lakes that connect to 

drainages containing bull trout either would be treated to have fish removed or 

treated and then stocked with low densities of nonreproducing fish; therefore, the 

potential for hybridization with bull trout and/or competition for resources would 

be unlikely under this alternative. Because lake treatment would occur over an 

extended period of time, and reproducing fish would not be removed from high 

mountain lakes immediately, it is recognized that bull trout in the Hozomeen and 

Sourdough drainages would be at some risk until all reproducing populations of 

nonnative trout were removed. Long-term beneficial effects would be realized as 

the program is completed. Bull trout may be affected, but are unlikely to be 

adversely affected, by fish stocking activities under alternative C. 

Chinook Salmon (Federal Threatened). Under alternative C, all lakes that 

connect to drainages containing Chinook salmon either would be treated to have 

fish removed or treated and then stocked with low densities of nonreproducing 

fish; therefore, the potential for predation or competition for resources would be 

very low under this alternative. Because lake treatment would occur over an 

extended period of time, and reproducing populations of fish would not be 

removed from high mountain lakes immediately, it is recognized that some 

impacts from stocked fish would occur until all reproducing populations of 

nonnative trout were removed. Long-term beneficial effects would be realized as 

the program is completed. Chinook salmon may be affected, but are unlikely to 

be adversely affected, by fish stocking activities under alternative C. 

Coho Salmon (Federal Candidate Species, State Candidate Species). Under 

alternative C, all lakes that connect to drainages containing Coho salmon either 

would be treated to have fish removed or treated and then stocked with low 

densities of nonreproducing fish; therefore, the potential for predation or 

competition for resources would be very low under this alternative. Because lake 

treatment would occur over an extended period of time, and reproducing 

populations of fish would not be removed from high mountain lakes 

immediately, it is recognized that some impacts from stocked fish would occur 

until all reproducing populations of nonnative trout were removed. Long-term 

beneficial effects would be realized as the program is completed. Coho salmon 

may be affected, but are unlikely to be adversely affected, by fish stocking 

activities under alternative C. 

Westslope Cutthroat Trout (Federal Species of Concern). Impacts on 

westslope cutthroat trout under alternative C would be the same as described for 

alternative B, with long-term beneficial effects from the reduction in density and 

elimination of nonnative reproducing fish, especially in McAlester Lake. Actions 

under alternative C, may affect, but are not likely to adversely affect, westslope 

cutthroat trout, although it is recognized that until all reproducing fish were 

removed from McAlester Lake, the potential for continued hybridization with 

westslope cutthroat trout would exist. 

State Listed and Other Special Status Wildlife Species. Under alternative C, 

six species (black-backed woodpecker, golden eagle, Lewis’ woodpecker, merlin, 

pileated woodpecker, and Vaux’s swift) may be affected, but are not likely to be 

adversely affected, by fish stocking and lake treatment activities. Noise impacts 

from fixed-wing aircraft, helicopters, or human presence may temporarily flush 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 319

individuals of these state candidate species if they are present near a lake when 

stocking or treatment activities are occurring, but this would not result in any 

detrimental impacts on these wildlife species. 

The common loon (Washington State sensitive species) may be adversely 

affected by actions under alternative C because stocked fish would be removed 

from Hozomeen Lake. Impacts would be the same as described for alternative B, 

which would be minor to moderate impacts on the pair of breeding loons that has 

nested at Hozomeen Lake since at least 1971. Adequate fish resources to support 

a family of loons may exist in nearby Ross, Ridley, and Willow lakes. Loons are 

declining in Washington due to loss of low-elevation lake habitat and associated 

human disturbances (Richardson et al. 2000). While the loss of habitat at 

Hozomeen Lake is unlikely to affect the overall population of common loons, at 

the local level, loons would be displaced from Hozomeen Lake and either would 

choose an adjacent area to nest or would discontinue to nest in the North 

Cascades Complex. Therefore, under alternative C, common loons nesting at 

Hozomeen Lake would incur minor to moderate impacts. 

Cumulative Impacts 

Cumulative impacts under alternative C would be similar to those described for 

alternative A but with substantially reduced impacts on amphibians and native 

fish from reductions in fish densities and/or removal of reproducing nonnative 

fish in the North Cascades Complex. 

Overall, the impacts associated with other projects, uses, and actions occurring in 

the region (as described under alternative A) added to the impacts predicted 

under alternative C, may affect, and are likely to adversely affect certain special 

status species in the region on a cumulative basis. Actions under alternative C 

would provide beneficial effects from the reduction of nonnative fish species, 

which would help limit the extent of cumulative impacts on native fisheries. 

However, the adverse impacts from development, water pollution, and other 

projects would cumulatively result in adverse impacts on many special status 

species. In most cases, an accurate determination of the magnitude of cumulative 

impacts on special status species cannot be made because available information 

and research on species’ biology, status, and distribution is insufficient. 

Additional research and population monitoring of special status species that 

would be affected by the alternatives in this plan/EIS, combined with research 

completed in the region, would help to better determine cumulative impacts. 

Conclusion 

Fixed-wing aircraft noise and human disturbance associated with periodic fishstocking activities under alternative C would have a range of short-term 

negligible to minor effects on some special status wildlife species but would be 

reduced from the effects that would occur under alternatives A and B. Short-term 

impacts related to lake treatments to remove fish would be minor, mostly due to 

noise from helicopters transporting lake treatment equipment and human 

disturbance during treatment activities. The use of the chemical, antimycin, to 

remove fish is not known to have adverse impacts on amphibians. There would 

be long-term beneficial effects on some aquatic species because most high-
E NVIRONMENTAL C ONSEQUENCES

320 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

density reproducing populations of fish would be replaced with low-density 

nonreproducing stocked fish. 

Based on the available information, alternative C would have no adverse effects 

on federally listed species from fish stocking or lake treatments to remove fish. 

Regarding federally listed species:

23 species may be affected but are not likely to be adversely affected

(American peregrine falcon, California wolverine, Canada lynx, gray wolf, 

grizzly bear, little willow flycatcher, marbled murrelet, Northern goshawk, 

Northern spotted owl, olive-sided flycatcher, Pacific fisher, Yuma myotis, 

long-eared bat, bald eagle, harlequin duck, Cascades frog, Columbia 

spotted frog, northern red-legged frog, Western toad, bull trout, Chinook 

salmon, Coho salmon, and westslope cutthroat trout). 

1 species would incur no effect (tailed frog). 

Regarding state-listed species that are not federally listed, 6 species would incur 

short-term negligible to minor adverse impacts from noise related to stocking and 

lake treatment activities, and the common loon would incur long-term minor to 

moderate adverse impacts due to the removal of its primary food source from 

Hozomeen Lake. 

Cumulative impacts on each special status species from projects or actions 

occurring throughout the region would be adverse; however, alternative C would 

contribute only a small increment to overall cumulative impacts. 

Impairment of special status wildlife species across the study area would not 

occur under alternative C. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS

The emphasis of this alternative would be to either maintain as fishless or 

eliminate fish from 62 of the 91 mountain lakes in the study area. All 91 lakes 

would eventually be unavailable for fishing as management actions are 

completed over time. 

The “Alternatives” chapter provides a detailed description of alternative D. For 

more information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed Lake 

Treatment Methods on 

Special Status Wildlife Species 

Similar to other alternatives, alternative D may affect, but is not likely to 

adversely affect, any of the following 11 species because these species either do 

not depend on lake resources, or only eat fish opportunistically, or would not be 

disturbed by activities associated with lake treatment. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 321

American Peregrine Falcon  federal species of concern, state endangered 

California Wolverine  federal species of concern, state candidate 

Canada Lynx  federal threatened, state threatened 

Gray Wolf  federal endangered, state endangered 

Grizzly Bear  federal threatened, state endangered 

Pacific Fisher  federal species of concern, state endangered 

Marbled Murrelet  federal threatened, state threatened 

Little Willow Flycatcher  federal species of concern 

Northern Goshawk  federal species of concern, state candidate 

Northern Spotted Owl  federal threatened, state endangered 

Olive-sided Flycatcher  federal species of concern 

The following 13 listed species are known to be present in the aquatic habitats of 

the 91 lakes or the adjacent habitats. The impacts on each species from 

alternative D are discussed below. 

Yuma Myotis (Federal Species of Concern). Similar to alternative A, Yuma 

myotis may be affected, but are unlikely to be adversely affected, by actions 

under alternative D. The species may experience a minimal amount of stress if 

lake treatment activities occur near a diurnal (daytime) roost. 

Long-eared Myotis (Federal Species of Concern). Similar to alternative A, 

Long-eared myotis may be affected, but are unlikely to be adversely affected, by 

actions under alternative D. The species may experience a minimal amount of 

stress if lake treatment activities occur near a diurnal (daytime) roost. 

Bald Eagle (Federal Threatened). Similar to alternative A, alternative D may 

affect but is not likely to adversely affect bald eagles because they only rarely, if 

ever, use the high-elevation lakes in the North Cascades Complex to forage or 

roost. 

Harlequin Duck (Federal Species of Concern). Similar to alternative A, 

implementation of alternative D, may affect, but is unlikely to adversely affect 

harlequin ducks through short-term, minor, and infrequent noise impacts from 

lake treatment activities. 

Cascades Frog (Federal Species of Concern). Cascades frogs have been 

documented in two ponds and one stream location in the Bridge Creek drainage 

(Bury et al. 2000). The species seems to be absent from lakes stocked with fish, 

and it is unknown if this absence is due to past predation from stocked trout or a 

preference for shallower waters. Removal of stocked fish from all lakes in the 

North Cascades Complex under alternative D would not affect Cascades frogs. 
E NVIRONMENTAL C ONSEQUENCES

322 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Removal of fish in all lakes under alternative D would benefit Cascades frogs as 

this unnatural source of predation would be eliminated. 

Columbia Spotted Frog (Federal Species of Concern, State Candidate 

Species). Under alternative D, adverse impacts on Columbia spotted frogs would 

be less than other alternatives. Fish would eventually be removed from lakes in 

the study area, resulting in long-term benefits to the frog. Lake treatment actions 

proposed under alternative D may affect, but are unlikely to adversely affect, 

Columbia spotted frogs. 

Northern Red-Legged Frog (Federal Species Of Concern). Northern redlegged frogs would incur long-term beneficial effects under alternative D, and 

adverse impacts on the species would be minimal and restricted to lake treatment 

activities to remove fish from study area lakes. Northern red-legged frogs may be 

affected, but are unlikely to be adversely affected, from implementation of 

alternative D. 

Tailed Frog (Federal Species of Concern). Tadpole and adult tailed frogs have 

been documented in the outlets of six lakes in the North Cascades Complex, 

including Upper Bouck and Nert lakes (Liss et al. 1995; Bury et al. 2000), which 

are currently stocked. The lakes would no longer be stocked under alternative D 

and would eventually become fishless. Some populations of tailed frogs have 

evolved in stream environments with fish predation (NPS, R. Glesne, pers. 

comm., 2003). In the North Cascades Complex, many populations are found in 

high-gradient tributaries that are inaccessible to fish. Under alternative D, threats 

to tailed frogs from predatory fish would cease. Removal of fish in Upper Bouck 

and Nert lakes would occur simply through discontinued stocking, and therefore, 

alternative D would have no impact on tailed frogs in the North Cascades 

Complex. 

Western Toad (Federal Species of Concern, State Candidate Species).

Impacts on Western toads from lake treatment would be similar to those 

discussed in alternatives B and C and would be limited to localized disturbances 

from human presence and habitat trampling. Western toads may be affected, but 

are unlikely to be adversely affected, by actions under alternative D. Western 

toads would benefit from elimination of fish in study area lakes. 

Bull Trout (Federal Threatened). Bull trout may be affected, but are unlikely to 

be adversely affected, by actions under alternative D. The long-term process of 

fish removal would eventually eliminate any future threats to bull trout inhabiting 

downstream basins connected to high mountain lakes—a beneficial effect. 

Chinook Salmon (Federal Threatened). Alternative D would provide longterm beneficial effects on Chinook salmon because most lakes would be treated 

for fish removal and no lakes would be stocked. As with other native fish species, 

Chinook salmon may be affected, but are unlikely to be adversely affected, by 

actions under alternative D. The long-term process of fish removal would 

eventually eliminate threats to Chinook salmon inhabiting downstream basins 

connected to high mountain lakes. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 323

Coho Salmon (Federal Candidate Species, State Candidate Species). 

Alternative D would provide long-term beneficial effects on Coho salmon 

because most lakes would be treated for fish removal and no lakes would be 

stocked. As with other native fish species, Coho salmon may be affected, but are 

unlikely to be adversely affected, by actions under alternative D. The long-term 

process of fish removal would eventually eliminate threats to Coho salmon 

inhabiting downstream basins connected to high mountain lakes. 

Westslope Cutthroat Trout (Federal Species of Concern). As with other 

native fish species, westslope cutthroat trout may be affected, but are unlikely to 

be adversely affected, by actions under alternative D. The long-term process of 

fish removal or reduction would eventually greatly reduce or eliminate threats to 

native fish inhabiting downstream basins connected to high mountain lakes—a 

beneficial effect. 

State Listed and Other Special Status Wildlife Species. Under alternative D, 

six species (black-backed woodpecker, golden eagle, Lewis’ woodpecker, merlin, 

pileated woodpecker, and Vaux’s swift) may experience negligible to minor 

adverse impacts from lake treatment actions. Noise impacts from helicopters 

transporting lake treatment equipment or human presence may temporarily flush 

individuals of these state candidate species if they are near a lake when treatment 

activities are occurring, but this would not result in any detrimental impacts on 

these wildlife species. 

The common loon (Washington State sensitive species) may be adversely 

affected under alternative D because stocked fish would be removed from 

Hozomeen Lake. Impacts would be the same as described for alternative B, 

which would be minor to moderate impacts on the pair of breeding loons that has 

nested at Hozomeen Lake since at least 1971. Adequate fish resources to support 

a family of loons may exist in nearby Ross, Ridley, and Willow lakes. Loons are 

declining in Washington due to loss of low-elevation lake habitat and associated 

human disturbances (Richardson et al. 2000). While the loss of habitat at 

Hozomeen Lake is unlikely to affect the overall population of common loons, at 

the local level, loons would be displaced from Hozomeen Lake and either would 

choose an adjacent area to nest or would discontinue to nest in the North 

Cascades Complex. 

Cumulative Impacts 

Cumulative impacts resulting from implementation of alternative D would be 

similar to those described for alternative A, but with extremely reduced effects to 

amphibians and native fish because of reduced fish densities and/or removal of 

reproducing nonnative fish in the North Cascades Complex. 

Overall, the impacts associated with other projects, uses, and actions occurring in 

the region (as described under alternative A), added to the impacts predicted 

under alternative D, may affect, and are likely to adversely affect, certain special 

status species in the region on a cumulative basis. Actions under alternative D 

would provide beneficial effects from the reduction of nonnative fish species, 

which would help limit the extent of cumulative impacts to native fisheries. 

Cumulatively, the adverse impacts from development, water pollution, and other 
E NVIRONMENTAL C ONSEQUENCES

324 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

projects would adversely affect many special status species. In most cases, an 

accurate determination of the magnitude of cumulative impacts on special status 

species cannot be made because available information and research on species’ 

biology, status, and distribution is insufficient. Additional research and 

population monitoring of special status species that would be affected by 

alternatives in this plan/EIS, combined with research completed in the region, 

would help to better determine cumulative impacts. 

Conclusion 

All fish stocking would be discontinued under alternative D. Short-term impacts 

related to lake treatments to remove fish would be minor, mostly due to noise 

from helicopters transporting lake treatment equipment and human disturbance 

during treatment activities. The use of the chemical, antimycin, to remove fish is 

not known to have adverse impacts on amphibians. 

Based on the available information, alternative D would have no adverse effects 

on federally listed species from lake treatments to remove fish. Regarding 

federally listed species:

22 species may be affected but are not likely to be adversely affected

(American peregrine falcon, California wolverine, Canada lynx, gray wolf, 

grizzly bear, little willow flycatcher, marbled murrelet, Northern goshawk, 

Northern spotted owl, olive-sided flycatcher, Pacific fisher, Yuma myotis, 

long-eared bat, bald eagle, harlequin duck, Cascades frog, Columbia 

spotted frog, northern red-legged frog, Western toad, bull trout, Chinook 

salmon, Coho salmon, and westslope cutthroat trout). 

2 species would incur no effect (Cascades frog and tailed frog). 

Regarding state-listed species that are not federally listed, 6 species would incur 

negligible to minor adverse impacts from noise related to fish removal activities, 

and the common loon would incur minor to moderate adverse impacts due to the 

removal of its primary food source from Hozomeen Lake. 

Cumulative impacts on each special status species from projects or actions 

occurring throughout the region would be adverse; however, alternative D would 

contribute only a small increment to overall cumulative impacts. 

Impairment of special status wildlife species across the study area would not 

occur under alternative D. 

METHODOLOGY AND ASSUMPTIONS 

FOR SPECIAL STATUS PLANT SPECIES 

Shoreline vegetation around lakes (riparian zones) may be sensitive to trampling 

by humans or stock (horses, mules, llamas). Many state special status plant 

species are expected to occur in riparian areas, although no surveys have been 

conducted to ascertain the presence or absence of these species at specific lakes 

(NPS, M. Bivin, pers. comm., 2004). In those lakes having riparian areas that 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 325

include marshes, wet meadows, bogs, seeps, stream edges, and swamps, the 

probability of having special plant species is higher. Potential impacts on state 

special status plants were estimated utilizing a methodology similar to that used 

in the “Vegetation” section in this chapter. Three factors were considered in the 

analysis: vegetation type, presence or absence of fish in a lake, and accessibility 

of a lake to anglers. 

V EGETATION T YPE

The general type of vegetation found at the shoreline was used as a proxy for the 

presence of special status species because no surveys to determine which special 

status plant species are present at each lake have been conducted. For example, 

shorelines that are dominated by bedrock, talus, and/or snow are assumed to have 

less habitat for sensitive plant species. Because the vast majority of the statelisted special status plant species grow in areas classified as having meadow or 

shrub cover (see appendix M), there may be a greater likelihood that lakes with 

high percentages of these potentially sensitive cover types would face more 

severe impacts from angler use than those with less sensitive cover types (forest 

and bare). Analysis methods are qualitative and based on analysis of cover types 

from aerial photographs (this is described in the “Vegetation” section of the 

“Affected Environment” chapter). Because the estimates of cover types have not 

been checked through ground surveys, information about the actual communities 

surrounding the lakes is lacking; therefore, in order to assess the potential 

impacts of the alternatives presented under this plan/EIS, it was necessary to use 

these unverified cover estimates in this analysis. 

P RESENCE OR A BSENCE OF F ISH 

Lakes that are not stocked are not likely to be visited for the purpose of fishing, 

and impacts caused by anglers at these lakes are expected to be negligible. 

A CCESSIBILITY OF THE L AKES TO A NGLERS 

Hendee et al. (1977, p. 10) found that the “ease of access, reflected by the 

distance and elevation gain to the lake, seemed to be directly related to the 

amount of use.” Trail access to the lake also influences the amount of visitation a 

lake receives. Most anglers prefer lakes with direct trail access, although some 

anglers prefer more remote and inaccessible lakes (WDFW, B. Pfeifer, pers. 

comm., 2004; C. Fowler, memorandum, 2003). 

The number of visitors, as well as the activities in which those visitors 

participate, can influence the degree to which vegetation is impacted. Average 

annual backcountry overnight use was estimated based on backcountry permit 

data from 1999 to 2002, which indicated that the average annual backcountry 

overnight use for all camps and cross-country zones near the 91 study area lakes 

was approximately 4,035 visitors per season (see the “Fishing” section under 

“Visitor Use and Experience” in the “Affected Environment” chapter and also 

“Map 2” and “Map 2 Table” located in the envelope that accompanied this 

plan/EIS). Analysis of backcountry permit data for the 2003 season (NPS 2003C) 
E NVIRONMENTAL C ONSEQUENCES

326 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

indicates that approximately 10.5% of all overnight visitors to camps and crosscountry zones intended to fish. Taking into account incomplete sampling due to 

dispersed access, highly variable and broad time of entry and departure, and 

purposeful or inadvertent avoidance of backcountry permit registration, a 

reasonable estimate of annual angling use of the study area lakes would be about 

1,000 people per year. The day-use visitor survey performed in 2003 indicates 

that about 75 of the 1,432 day-use visitors were engaged in fishing at the study 

area lakes (see table 25 in the “Affected Environment” chapter). More 

information on visitor use would allow for a more accurate assessment of the 

impacts that anglers have on high mountain lakes. For the purpose of analyzing 

impacts on special status plant species, three levels of visitor use were defined. 

Low: 0 to 34 visitors of which 0 to 4 were estimated to be anglers 

Medium: 35 to 99 visitors of which 4 to 10 were estimated to be anglers 

High: 100 to 450 visitors of which 11 to 47 were estimated to be anglers 

It is important to reiterate that impacts on special status plant species are 

unknown, and even very light visitor or angler use at a given lake (see the 

“Map 2 Table”) would result in major localized impacts on a particular species. 

This is because any trampling of even a very small population of a rare plant has 

the potential to have a major impact on the species; however, their rarity may 

also decrease the likelihood of anglers coming into contact with the plants and 

may serve to protect localized pockets of a plant species from impacts associated 

with fishing. Without plant surveys or visitor use information, the impact 

analysis must be based on the assumptions stated above. Actions that can be 

taken to reduce impacts include surveys and subsequent monitoring of indicator 

or rare plants at lakes before management actions are implemented, erecting 

signs and fencing, relocating (or even closing) trail access, and establishing other 

important mitigation measures. 

Beyond the loss of plants through trampling, angler use may cause indirect 

effects such as erosion and sedimentation, alteration of plant communities, and 

alteration of food and nutrient inputs to surrounding lakes and creeks. In some 

cases, bare ground may be exposed leading to soil erosion in subalpine and alpine 

areas where natural recovery is difficult, and restoration efforts require years of 

work. Additionally, trampling may lead to changes in site hydrology, which may 

exclude sensitive wetland species from impacted sites. Due to lack of data for 

both trail and off-trail lake access by anglers, it was not possible to assess the 

impact anglers have non-lakeshore communities that visitors travel through to 

reach the lakes. 

F EDERALLY L ISTED P LANTS

No federally listed plant species or species proposed for listing occur in the North 

Cascades Complex, therefore, none of the activities described in any of the 

alternatives would affect federally listed plant species. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 327

I MPACT T HRESHOLD

D EFINITIONS FOR S TATE L ISTED

S PECIAL S TATUS P LANT S PECIES

The following thresholds were used to evaluate the degree of impact from fishery 

management activities on state listed special status plant species: 

Negligible. Impacts would have no measurable or perceptible changes in plant 

community size, integrity, or continuity. 

Minor. Impacts would be measurable or perceptible but would be localized 

within a relatively small area. The overall viability of the plant community would 

not be affected and, if left alone, would recover. 

Moderate. Impacts would cause a change in the plant community (such as its 

abundance, distributions, quantity, or quality); however, the impact would remain 

localized. 

Major. Impacts on the plant community would be substantial, highly noticeable, 

and permanent. 

Impairment. The action would contribute substantially to the deterioration of 

special status plant species in the North Cascades Complex to the extent that the 

special status plants would no longer function within a natural system. In 

addition, these adverse major impacts on the North Cascades Complex’s 

resources and values would 

contribute to deterioration of special status plant resources and values to 

the extent that the purpose of the North Cascades Complex would not be 

fulfilled as established in its enabling legislation 

affect resources key to the natural or cultural integrity or opportunities for 

enjoyment in the North Cascades Complex 

affect the resource whose conservation is identified as a goal in the 

General Management Plan (NPS 1988b) or other planning documents for 

the North Cascades Complex 
E NVIRONMENTAL C ONSEQUENCES

328 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

IMPACTS OF THE ALTERNATIVES 

ON SPECIAL STATUS PLANT SPECIES 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A (no action) would continue existing management practices in the 

91 lakes in the study area. The “Alternatives” chapter provides a detailed 

description of alternative A. For more information on the 91 lakes, refer to 

table 5 and figure 4 in the “Alternatives” chapter and appendix E. 

No federally listed plant species occur in the North Cascades Complex. Statelisted special status plant species occur in the North Cascades Complex (see 

appendix C, table C-2), although no surveys have been undertaken to determine 

the presence or absence of these species at specific lakes. Therefore, it is 

unknown whether any particular species exists at a given lake. Appendix C 

provides an overview of state of Washington special status plant species and 

potential habitats. More than half of the species listed in this appendix may occur 

as shoreline vegetation including marshes, wet meadows, bogs, seeps, stream 

edges, and swamps. Those lakes with a higher percent ground cover of meadow 

(see appendix M) are more likely to provide habitat for these species, and 

generally, the likelihood of impact from trampling would be higher. In addition, 

low woody species with brittle stems (e.g., Salix spp.) and tree seedlings are 

resistant to low levels of trampling but recover slowly following damage at high 

levels of trampling (Cole and Trull 1992). Lakes with a higher percentage of 

shrub ground cover are more likely to provide habitat for these species and may 

also be impacted at higher levels than areas with no cover (bare). 

Impacts of Current Fish Stocking on 

State-Listed Special Status Plant Species 

Using methodology similar to that described for the “Vegetation” section in this 

chapter, of the 62 lakes available for fishing under alternative A, 52 are classified 

as having meadow and 7 are classified as having shrub cover in the shoreline 

vegetation (see appendix M). For the lakes with these types of shoreline cover, 

and that experience low visitor use, fish stocking has and may continue to have 

only negligible to minor adverse impacts on any special status plant species. For 

the remainder of lakes receiving medium to high visitor use (visitor use levels 

can be found on “Map 2 Table”), continued fish stocking would result in shortterm negligible to major adverse impacts on any state special status species that 

might grow in the shoreline environment. For the lakes with no shoreline 

classified as meadow or shrub, adverse impacts on any state special status species 

may be negligible to moderate. It was not possible to determine if any of these 

communities include any state-listed special status species, which is why the 

range of potential impacts is so broad. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 329

Impacts of Lake Treatment 

Methods on State-Listed 

Special Status Plant Species 

No lakes are proposed for fish removal under alternative A; therefore, impacts 

would be negligible. 

Cumulative Impacts 

Visitor use is expected to follow the same patterns that it has for several years. 

Trampling by horses, mules, or llamas may also occur in areas around lakes. This 

trampling, combined with angler use, other visitor use, and fish stocking, is likely 

to result in minor to moderate cumulative impacts at some lakes and moderate to 

major at others, depending on the intensity of use and location of sensitive plant 

species. 

Conclusion 

Fish-stocking activities at lakes with shoreline meadow or shrub vegetation 

would have short-term negligible to minor adverse impacts on any special status 

plants in the shoreline areas of lakes in zones or near camps with low visitor use. 

Stocking activities at lakes in zones or near camps with medium to high visitation 

would result in short-term negligible to major adverse impacts on any special 

status plants. 

No lakes are treated for fish removal under alternative A. 

Trampling by stock (horses, mules, llamas) and visitors (anglers and other 

visitors) would likely result in minor to moderate cumulative impacts at some 

lakes and moderate to major at others, depending on the intensity of use and 

location of sensitive plants. 

Impairment of special status plant species across the study area would not occur 

under alternative A. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The goal of this alternative is to eliminate or reduce reproducing fish from select 

lakes in the study area. Forty-two lakes would potentially be available for fishing. 

Of these, 29 lakes would continue to have fish, and 13 lakes would be evaluated 

for restocking. Twenty lakes would revert to fishless conditions, and the 

29 currently fishless lakes would remain fishless. The “Alternatives” chapter 

provides a detailed description of alternative B. For more information on the 91 

lakes, refer to tables 5 and 10 in the “Alternatives” chapter and appendix E. For 

additional information on shoreline vegetation, see the “Vegetation” section in 

this chapter and appendix M. 
E NVIRONMENTAL C ONSEQUENCES

330 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Of the 42 lakes that may potentially be available for fishing (refer to table 10), 

35 have some amount of meadow shoreline vegetation. Twenty-two of the 

35 lakes are within cross-country zones or near camps that experience medium or 

high visitor use, and impacts may remain negligible to moderate over time. The 

other 13 lakes that have meadow vegetation, and may potentially be available for 

fishing under this alternative, have fewer than 34 annual visitors in a given year 

and very little trail access. Impacts on state-listed special status plant species at 

these 13 lakes may be negligible or minor. 

Impacts of Proposed Fish Stocking on 

State-Listed Special Status Plant Species 

Alternative B proposes the discontinuation of stocking or removal of fish in 

44 lakes, as well as the restocking of 24 of those lakes after evaluation or 

monitoring (refer to tables 5 and 10 in the “Alternatives” chapter). Twenty-one of 

the 24 lakes that may be restocked have some meadow vegetation around the 

shore that is vulnerable to trampling (3 of the 24 lakes have no meadow 

vegetation at present). Should the 21 lakes be restocked, impacts would not 

change from what they are now. Fourteen of the 21 lakes are within crosscountry zones or near camps that have medium or high levels of visitor use, with 

the possibility of short-term negligible to moderate adverse impacts on meadow 

vegetation. Seven of the 21 lakes that may be restocked are within zones or near 

camps that have low visitor use and may experience negligible or minor impacts 

on meadow riparian vegetation. If the lakes are not restocked, negligible to 

moderate beneficial effects on meadow vegetation may occur. 

Impacts of Proposed Lake 

Treatment Methods on StateListed Special Status Plant Species 

The use of mechanical or chemical method to remove fish would involve 

trampling of riparian or wetland vegetation, but mitigation measures described in 

appendix I would be implemented; those include maximizing the use of boats or 

wading in the lake to avoid sensitive lakeside vegetation. With mitigation 

measures in place, the impact of fish removal activities on state-listed plants 

would be negligible to minor. 

Natural Methods. A total of 12 lakes under alternative B would receive natural 

treatment to remove fish. Natural treatment is the cessation of stocking, which 

over time would mean the die-off of all fish in a lake. During this period of dieoff, fishing and any associated trampling would continue with impacts as 

described above; however, a similar and permanent benefit from the eventual 

elimination of all angler-related foot traffic would eventually occur. 

Mechanical Methods. Mechanical methods would be used to treat up to 8 lakes. 

Impacts on state special status plant species would likely be short term and range 

from negligible to minor if personnel involved in removing fish are trained to 

avoid state-listed special status plant species. 

Chemical Method. Chemical treatment is proposed for 19 lakes. There would be 

a short-term negligible impact on state special status plant species from human 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 331

activity in an area during chemical removal of reproducing fish, but the proposed 

chemicals should have no effect on plant species. 

Cumulative Impacts 

Visitor use beyond angling is expected to follow the same patterns that it has for 

several years. Trampling by horses, mules, or llamas may also occur in areas 

around lakes. This trampling, combined with angler use, other visitor use, and 

lake treatment and fish stocking activities, would result in negligible cumulative 

impacts on state-listed special status plant species at some lakes and moderate or 

major cumulative impacts at other lakes, depending on the intensity of use and 

location of sensitive plants. 

Conclusion 

Fewer lakes would be stocked under alternative B. Trampling during stocking 

activities may result in short-term negligible to moderate adverse impacts on any 

special status plants that may be present in the shoreline of lakes that are in crosscountry zones or near camps that receive medium to high use, and negligible to 

minor adverse impacts at lakes in zones or near camps that have low visitor use. 

There would long-term beneficial effects on special status plant species at lakes 

where stocking would not occur. 

Select lakes would be treated for fish removal under alternative B. Trampling 

during mechanical and chemical lake treatment activities may result in short-term 

negligible to minor adverse impacts on any special status plants that may be 

present in the shoreline of lakes that are in cross-country zones or near camps 

that receive medium to high visitor use, and negligible to minor adverse impacts 

at lakes in zones or near camps that have low visitor use. 

Trampling by stock (horses, mules, llamas) and visitors (anglers and other 

visitors) would likely result in negligible cumulative impacts at some lakes and 

moderate to major at others depending on the intensity of use and location of 

sensitive plants. 

Impairment of special status plant species across the study area would not occur 

under alternative B. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Under alternative C, 9 lakes in Ross Lake and Lake Chelan National Recreation 

Areas would have fish and 2 lakes would be evaluated for restocking. Eleven 

other lakes in the national recreation areas would remain fishless or be returned 

to fishless conditions. The remaining 69 lakes (which are in the national park) 

would be returned to their natural fishless conditions or would remain fishless. 
E NVIRONMENTAL C ONSEQUENCES

332 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed Fish Stocking on 

State-Listed Special Status Plant Species 

There would potentially be 80 lakes unavailable for fishing in alternative C, as 

opposed to 29 in alternative A. This alternative would benefit state-listed plant 

species. 

Currently, of the 9 lakes that would remain available for fishing, 3 are classified 

as having at least some meadow, wetland, or shrub cover in its shoreline 

vegetation and are classified as high- to moderate-use areas. Impacts from sport 

fishing may be negligible to major at these lakes. The remaining lakes experience 

low visitor use and/or have no shoreline classified as meadow, wetland, or shrub. 

These lakes are more likely to experience negligible to moderate impacts on 

state-listed plant species. 

Impacts of Proposed Lake 

Treatment Methods on StateListed Special Status Plant Species 

Fifty-five lakes are proposed for fish removal under alternative C. 

Natural Methods. Twenty-one lakes would be treated with natural methods to 

remove fish. Natural treatment is usually the cessation of stocking, which over 

time would mean the die-off of all fish in a lake. During this period of die-off, 

angling and any associated trampling would continue with impacts as described 

above; however, a similar and permanent benefit from the eventual elimination of 

all angler-related foot traffic would eventually occur. 

Mechanical Methods. Mechanical treatment is proposed for up to 10 lakes. 

Impacts on state special status plant species would be short-term negligible to 

minor if personnel involved in removing fish were trained to avoid state-listed 

special status plant species. 

Chemical Method. A total of 25 lakes are proposed for chemical treatment. 

There would be a short-term negligible impact on state-listed species from 

human activity associated with chemical removal of reproducing fish, but the 

proposed chemicals should have no effect on plant species. 

Cumulative Impacts 

Visitor use is expected to follow the same patterns that it has for several years. 

Trampling by horses, mules, or llamas may also occur in areas around lakes. This 

trampling, combined with decreases in angler use, would result in negligible to 

minor cumulative impacts, depending on the intensity of use and location of 

sensitive plants. These impacts over the long term would be reduced to a 

negligible level as lake treatments are completed, although more serious impacts 

resulting from non-angler visitor use would still be possible. 
Special Status Species 

ENVIRONMENTAL IMPACT STATEMENT 333

Conclusion 

Considerably fewer lakes would be stocked under alternative C than under 

alternatives A and B. Trampling during stocking activities may result in shortterm negligible to moderate adverse impacts on any special status plants that may 

be present in the shoreline of lakes that are in cross-country zones or near camps 

that receive medium to high use, and negligible to minor adverse impacts at lakes 

in zones or near camps that have low visitor use. There would long-term 

beneficial effects on special status plant species at lakes where stocking would 

not occur. 

A higher number of lakes would be treated for fish removal under alternative C 

than under alternative B. Trampling during mechanical and chemical lake 

treatment activities may result in short-term negligible to minor adverse impacts 

on any special status plants that may be present in the shoreline of lakes that are 

in cross-country zones or near camps that receive medium to high use, and 

negligible to minor adverse impacts at lakes in zones or near camps that have low 

visitor use. 

Trampling by stock (horses, mules, llamas) and visitors (anglers and other 

visitors) would likely result in negligible to minor cumulative impacts depending 

on the intensity of use and location of sensitive plants. These impacts over the 

long term would be reduced to a negligible level as lake treatments are 

completed. 

Impairment of special status plant species across the study area would not occur 

under alternative C. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Under alternative D, all 91 lakes would be fishless. 

The “Alternatives” chapter provides a detailed description of alternative D. For 

more information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” 

chapter and appendix E. 

All lakes potentially would be unavailable for fishing in alternative D, as 

opposed to 62 in alternative A; therefore, this alternative is most likely to benefit 

state special status plant species because sport fishing would eventually be 

eliminated in the study area lakes. 

Under this alternative, there would be a widespread beneficial effect. 

Impacts of Proposed Fish Stocking on 

State-Listed Special Status Plant Species 

Stocking would not occur in any of the study area lakes. 
E NVIRONMENTAL C ONSEQUENCES

334 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Impacts of Proposed Lake 

Treatment Methods on StateListed Special Status Plant Species 

Sixty-two lakes are proposed for fish removal under alternative D. 

Natural Methods. A total of 26 lakes would receive natural treatment to remove 

fish. Natural treatment is usually the cessation of stocking, which over time 

would mean the die-off of all fish in a lake. During this period of die-off, angling 

and any associated trampling would continue with impacts as described above; 

however, a similar and permanent benefit from the eventual elimination of all 

angler-related foot traffic would eventually occur. 

Mechanical Methods. Up to 11 lakes are proposed for mechanical treatment. 

Impacts on state special status plant species would be short-term negligible to 

minor if personnel involved in removing fish were trained to avoid state-listed 

special status plant species. 

Chemical Method. A total of 25 lakes are proposed for chemical treatment. 

There may be a short-term negligible impact on state-listed species from human 

activity associated with chemical removal of reproducing fish, although the 

proposed chemicals themselves should have no effect on plant species. 

Cumulative Impacts 

Visitor use is expected to follow the same patterns that it has for several years. 

Trampling by horses, mules, or llamas may also occur in areas around lakes. 

Decreases in angler use may offset some of these continuing impacts, but the 

possibility of negligible to minor cumulative impacts on state special status plant 

species from activities not related to angling would remain. These impacts over 

the long term would be reduced to a negligible level as lake treatments are 

completed. 

Conclusion 

Fish stocking would not occur under alternative D, which would result in longterm beneficial effects on special status plant species. 

Mechanical and chemical lake treatment activities to remove fish would result in 

short-term negligible to minor adverse impacts. 

Trampling by stock (horses, mules, llamas) and visitors would likely result in 

negligible to minor cumulative impacts depending on the intensity of use and 

location of sensitive plants. These impacts over the long term would be reduced 

to a negligible level as lake treatments are completed. 

Impairment of special status plant species across the study area would not occur 

under alternative D. 
ENVIRONMENTAL IMPACT STATEMENT 335

VEGETATION 

GUIDING REGULATIONS AND POLICIES 

The General Management Plan (NPS 1988b) includes the following 

management objectives that are relevant to overall natural resources for the North 

Cascades Complex, including vegetation: 

To increase knowledge and understanding of the interrelationships of the 

natural processes, and of methods for implementation of appropriate 

actions. 

To preserve, maintain, or restore, where feasible, the primary natural 

resources and those ecological relationships and processes. 

To manage the natural resources as an integral part of a regional 

ecosystem. 

To provide opportunity for research in as natural a system as possible. 

The Strategic Plan (NPS 2000a) also includes goals for preserving park 

resources that are consistent with the goals and objectives of this analysis. 

Mission Goal I.a. states, “Natural and cultural resources and associated values of 

the North Cascades National Park Service Complex are protected, restored, and 

maintained in good condition and managed within their broader ecosystem and 

cultural context.” 

Servicewide NPS regulations such as the Organic Act of 1916 and the NPS 

Management Policies (NPS 2001a) also direct parks to provide for the protection 

of park resources, including shoreline vegetation. The NPS Management Policies 

state that “Where human activities or structures have altered the nature or rate of 

natural shoreline processes, the Service will, in consultation with appropriate 

state and federal agencies, investigate alternatives for mitigating the effects of 

such activities or structures and for restoring natural conditions.” 

METHODOLOGY AND 

ASSUMPTIONS FOR VEGETATION 

A primary concern identified in the public scoping process was that of adverse 

effects of fish stocking on native plant species near mountain lakes. All visitors 

to the mountain lakes in the North Cascades Complex may impact shoreline 

vegetation through (1) trampling by humans or stock (horses, mules, or llamas); 

(2) activities associated with camping; (3) activities associated with fishing; and 

(4) indirect impacts, which can include increased erosion and sedimentation 

rates, depending on the particular shoreline cover surrounding a lake. These 

impacts may be long term because vegetation grows slowly in the short growing 

season of the mountains, and soil compaction or erosion makes regrowth of 

vegetation even more difficult. 
E NVIRONMENTAL C ONSEQUENCES

336 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

S OURCES OF I NFORMATION

In order to assess impacts associated with fish stocking and angling, it was 

necessary to consider (1) which plant communities are found in areas likely to be 

affected by fishery management actions described in the alternatives, and 

(2) effects of angling on different plant communities above and beyond effects of 

other visitors. 

Plant communities around the shoreline of study area lakes (see appendix M) 

were described using aerial photos. Lake perimeter distance was estimated by onscreen digitizing of shoreline distance using 1:12000 black and white Digital 

Orthophoto Quads. Lakeshore vegetation cover types were estimated from 

1:12000 color photos (false color infrared) analyzed in stereo (3-dimensional). 

Cover-type values are percentages of the total perimeter for each lake within an 

82-foot buffer defined as the riparian zone. The photographs were taken in 

August 1998 (NPS 2003a). It is important to note that the aerial photos only offer 

large-scale estimates of cover and have not been checked through ground 

observations; therefore, precise information about the actual vegetation 

communities surrounding the lakes is lacking. Impact predictions are 

characterized as ranges (for example, minor to moderate) primarily for this 

reason. 

In addition, the data available on lake visitation by anglers versus all other 

recreational users is incomplete and sometimes contradictory. In a study of high 

mountain lakes conducted by Hendee et al. (1977), the researchers concluded that 

“manipulating the fishery to modify visitation at high lakes is, at best, a partial 

solution” because other visitors would continue to affect the resources. Many 

anglers observed and interviewed during the course of the study cited reasons 

other than fishing as their primary motivation for visiting the lakes, which 

suggests that their use patterns may not change as a result of fish removal. On the 

other hand, research conducted in the late 1980s by Hospodarsky and Brown 

(1992) suggests that anglers spent three times longer in riparian zones than other 

user groups. The researchers hypothesized that if time spent in the riparian zone 

were proportionate to impacts, then anglers would have up to three times as great 

an impact as hikers (Hospodarsky and Brown 1992). This hypothesis has yet to 

be tested. It is also important to note that many anglers fish with rafts, which 

limits trampling of riparian vegetation (WDFW 2001). 

Scientific literature was consulted to obtain additional information that factors 

into the impact analysis. Work done by Cole and Trull (1992) shows that both 

plant stature and location of perennating tissues at or below the ground, influence 

the ability of vegetation types to resist and recover from trampling. Tall, tough, 

woody shrubs and grasses that occur in bunches or as turf (for example, Carex

spp.) were most resistant to damage by trampling. Low, woody species with 

brittle stems (such as Phyllodoce spp.) and tree seedlings resisted low levels of 

trampling but were sensitive to high levels of trampling. Broad-leaved 

herbaceous species were most sensitive to the effects of trampling. Species that 

recovered most quickly following damage were fast-growing herbaceous species 

or tufted or turf-producing grasses. Woody species, as well as more uncommon 

broad-leaved species that suffered damage to their regenerative tissues recovered 

more slowly following damage. 

Perennating: to 

survive from one 

growing season to 

the next with 

reduced or arrested

growth between 

seasons.
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 337

The trampling of 

vegetation and 

creation of social 

trails are a common 

problem, especially in 

subalpine areas. Photo 

is of Sahale Arm with 

Doubtful Lake in the 

background (date 

unknown).

Potential indirect impacts of trampling include increased erosion 

and sedimentation rates associated with loss of roots and the 

plants’ ability to hold soils and compaction of riparian soils. 

Reduced lakeshore vegetation may reduce organic matter input, 

thereby altering patterns of nutrient cycling. Terrestrial insects and 

other organisms that get into the lake and become prey to aquatic 

organisms may also be affected indirectly through loss of shoreline 

vegetation that serves as habitat. There are no data on the levels of 

indirect impacts anglers may have on lakeshore environments; 

therefore, it was only possible to describe the impact qualitatively. 

Anglers and other visitors traveling cross-country or off trail to 

reach certain remote lakes would adversely affect vegetation, but 

there is no available information on the degree of impact or even 

the vegetative communities where such an impact might take place. The WDFW 

believes that no conclusions are possible; however, comparative conclusions are 

common in environmental impact statements. The impact is, therefore, 

considered a possibility and described qualitatively, but no assessment on the 

degree of impact is possible. 

A SSUMPTIONS 

As noted above, the number of visitors, as well as the activities in which those 

visitors participate, can influence the degree to which vegetation is impacted. 

Since neither data specific to particular plant communities nor particular impacts 

of anglers at the 91 study area lakes were available, the potential impact to plant 

communities around mountain lakes was tied to the fishing potential of a given 

lake, the level of visitor use in the cross-country zones or established camps near 

the 91 lakes, and the cover types that are present in the 82-foot riparian zone 

surrounding the lakes in the study area. 

Average annual backcountry use was estimated based on backcountry permit data 

from 1999 to 2002. The data are not lake specific but based on backcountry 

overnight use permits issued for cross-country zones or camps located near lakes. 

Data from the backcountry overnight use permit database for 2003 suggest that 

anglers comprise about 10.5% of all backcountry overnight visitors to the 91 

lakes in the study area (NPS 2003c). Data on day use by anglers was estimated 

for 7 of the lakes (refer to table 25 in the “Affected Environment” chapter). More 

information on visitor use would allow for a more accurate assessment of the 

impacts that anglers have on specific mountain lakes. For the purpose of 

analyzing the impacts on vegetation, three levels of visitor use were considered 

(see appendix M for shoreline cover data and “Map 2” and “Map 2 Table” for 

more information on the average annual overnight visitation at the 91 lakes). 

Low: 0 to 34 visitors of which 0 to 4 were estimated to be anglers 

Medium: 35 to 99 visitors of which 4 to 10 were estimated to be anglers 

High: 100 to 450 visitors of which 11 to 47 were estimated to be anglers 
E NVIRONMENTAL C ONSEQUENCES

338 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Deciduous: Trees 

that lose their leaves

 at the end of the 

growing season; also 

called hardwoods.

Trail and stock (horses, mules, llamas) access to lakes may result in trampling of 

vegetation and changes in the hydrology of impacted sites. Although trail and 

stock access would influence the extent of shoreline impacts to a given lake, it is 

difficult to identify those lakes that hold an increased interest to anglers; 

therefore, no assumptions in this regard were considered valid and none were 

made. 

The following assumptions regarding vegetative cover were made based on the 

aerial surveys described above under “Sources of Information” (appendix M lists 

the shoreline cover types for the 91 lakes in the study area). 

Deciduous and/or coniferous trees are dominant in the forest cover type. 

Shrub cover type is characterized by the predominance of woody shrubs. 

Meadow cover describes areas where forbs and graminoids (grasses) are 

dominant, but may include low-lying shrubs as well. 

Areas that are not vegetated are assigned to the bare cover type and include 

exposed bedrock, talus slopes, and cliffs (talus slopes may contain plants, 

but the frequencies at which they occur have not been quantified; therefore, 

talus slopes are included in the bare cover type [Liss 1995; NPS, M. Bivin, 

pers. comm., 2004]). 

Methods Used to Analyze Impacts 

For a given lake, impacts on vegetation were determined using the following 

methods: 

Classifying the type of shoreline surrounding the lake. For example, shorelines 

that are dominated by bedrock, talus, and/or snow may not be as sensitive to 

trampling as lakeshores with an abundance of low meadow vegetation or lowlying shrub species that recover slowly following damage. At lakes that have 

high percentages of potentially sensitive cover types (that is, shrub and meadow 

types), the vegetation is more likely to face more severe impacts due to angler 

use than at those lakes with less sensitive cover types (bare of vegetation). 

Identifying whether or not the lake provides a fishing opportunity. Evidence 

suggests that anglers use riparian areas more extensively than other visitors. 

Lakes with fish are likely to experience a greater impact on riparian community 

types than fishless lakes. For those fishless lakes that are to remain fishless in all 

alternatives, the potential impacts on vegetation would be negligible and would 

resemble other lakes in the park where fishing does not occur. 

Identifying those lakes where stock (horses, mules, llamas) have direct access to 

the shoreline and the lake. Although it is extremely difficult to identify one type 

of user as the reason for shoreline impacts, lakes such as McAlester Lake are 

known to have impacts from stock associated with the shoreline vegetation of the 

lake. If a lake is available for fishing, has stock access, and has a high percentage 

of cover types that are sensitive to trampling (i.e., huckleberry-heather shrub 

communities), impacts would be greater than at other lakes that do not have these 

factors associated with them (refer to table 23 in the “Affected Environment” 

chapter for lakes accessible by horseback). 
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 339

Identifying those lakes that are most accessible. Hendee et al. (1977) found that 

the “ease of access, reflected by the distance and elevation gain to the lake, 

seemed to be directly related to the amount of use.” Trail access to the lake also 

influences the amount of visitation a lake receives. Most anglers prefer lakes with 

direct trail access, although some anglers prefer more remote and inaccessible 

lakes (WDFW, B. Pfeifer, pers. comm., 2004; WDFW, B. Fowler, pers. comm., 

2003). 

D EFINITIONS OF I NTENSITY L EVELS

Negligible. Impacts would have no measurable or perceptible changes in plant 

community size, integrity, or continuity. 

Minor. Impacts would be measurable or perceptible but would be localized 

within a relatively small area. The overall viability of the plant community would 

not be affected and, if left alone, would recover. 

Moderate. Impacts would cause a change in the plant community (such as 

abundance, distributions, quantity, or quality); however, the impact would remain 

localized. 

Major. Impacts on the plant community would be substantial, highly noticeable, 

and permanent. 

Impairment. The action would contribute substantially to the deterioration of 

vegetation in the North Cascades Complex to the extent that vegetation would no 

longer function as a natural system. In addition, these adverse major impacts on 

the North Cascades Complex’s resources and values would 

contribute to deterioration of these resources to the extent that the North 

Cascades Complex’s purpose would not be fulfilled as established in its 

enabling legislation 

affect resources key to the North Cascades Complex’s natural or cultural 

integrity or opportunities for enjoyment 

affect the resource whose conservation is identified as a goal in the 

General Management Plan or other planning documents for the North 

Cascades Complex 

IMPACTS OF THE 

ALTERNATIVES ON VEGETATION 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

The current mountain lakes fishery management activities at the North Cascades 

Complex, which are described in the “Alternatives” chapter, would continue 

under the no-action alternative. For more information on the 91 lakes, refer to 
E NVIRONMENTAL C ONSEQUENCES

340 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A well-used campsite

 at Stout Lake.

The backcountry 

overnight use permit

data are not lake 

specific but based on 

backcountry 

overnight use 

permits issued for

cross-country zones 

or camps near the 

91 lakes in the 

study area.

table 5 and figure 4 in the “Alternatives” chapter, appendix E, appendix M, and 

“Map 2” and “Map 2 Table” located in the envelope that accompanied this 

document.

Impacts of Current Fish Stocking 

on Vegetation (Riparian Vegetation) 

Trampling from visitor use, including hiking, fishing and 

stock (horses, mules, llamas) use, would continue at 

current levels or worsen around the shorelines of wellused lakes if alternative A were selected. The degree of 

these impacts would vary and range from negligible to 

moderate depending on the factors identified under 

“Methodology and Assumptions” in this section; these 

factors include the type and extent of vegetation, access, 

fishing potential, availability of overnight camping, and 

stock access. Impacts would be more likely where a 

lake’s shoreline is covered in meadow or wetland 

vegetation. Of the 62 lakes that would continue to have 

fish in this alternative, 52 lakes are classified as having 

from 2% to 76% meadow in the shoreline; cover data is 

absent for one lake. 

Of the 52 lakes that contain fish and have shoreline meadow vegetation, 20 lakes 

are located in cross-country zones or are near established camps that have low 

visitor use—continued fish stocking is expected to have only negligible adverse 

impacts on vegetation at these lakes. Another 19 lakes with shoreline meadow 

vegetation are in zones or near camps that have a medium level of visitor use—

continued fish stocking in these lakes would result in negligible to minor adverse 

impacts on meadow vegetation. Negligible to moderate adverse impacts on 

shoreline meadow vegetation would occur at 13 lakes that are in cross-country 

zones or near camps that receive high visitor use. 

These assessments of impacts are broad for several reasons. Because impacts due 

to anglers alone have not been investigated, it is difficult to determine how 

continued fish stocking may affect riparian communities. A single angler who 

spends the majority of the time in meadow or shrub communities would 

potentially have a significant local impact on sensitive vegetation. Anglers who 

use rafts and limit the time spent along the shoreline would unlikely have more 

than a negligible impact on the riparian vegetation of the lakes they visit. 

Negligible to moderate adverse impacts would occur at the 7 lakes where shrub 

communities are present and meadow communities are not. It is not possible to 

determine if more resistant high-stature shrubs (such as willows) or sensitive 

low-lying shrubs (such as heather and huckleberry) are dominant at individual 

lakes, which is why the range of potential impact is broad. Forest cover 

dominates shoreline at one lake that experiences low visitor use, and thus, fish 

stocking may have negligible adverse impacts. Forest cover is dominant at 

2 lakes that experience high visitor use; the effects of continued fish stocking at 

these lakes would be negligible to minor and adverse. One lake with fish is 
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 341

classified as having only the bare cover type in the riparian zone, so impacts at 

this lake would be negligible. 

The 29 lakes that are currently fishless experience negligible impacts from fish 

stocking. 

Impacts of Lake Treatment Methods 

on Vegetation (Riparian Vegetation) 

No lakes are currently treated or would be treated for fish removal in the future 

under alternative A; therefore, impacts would be negligible. 

Impacts of Other Mitigation 

To reduce effects of visitors (including anglers) on shoreline vegetation and on 

other visitors’ wilderness experience, additional visitor education efforts toward 

leave-no-trace visits would be instituted. This would decrease the overall adverse 

impacts to those lakes with an abundance of meadow and shrub cover types 

depending on the effectiveness of the campaign on the visitors to these lakes. 

Cumulative Impacts 

Under alternative A, cumulative impacts on shoreline vegetation from other 

recreationists may be negligible to moderate when added to those from angler 

use. Although use by anglers and other visitors (including visitors with stock—

horses, mules, or llamas) may increase in the future, there is little likelihood that 

their shoreline activities would affect the overall integrity of the plant community 

greater than moderate impacts. No projects are proposed or in planning stages 

that would change the road access to any unit of the North Cascades Complex, 

and no new trails or trailheads are being considered; consequently, there would 

be no increase in impacts resulting from new trails to the mountain lakes in the 

North Cascades Complex. 

Conclusion 

Fifty-nine of the 62 lakes in the study area where fishing would continue have 

meadow and/or shrub vegetation. Of these, about 75% have low to medium 

visitation, and vegetation would experience only negligible impacts. The 

remaining 25% that have high visitation would continue to experience minor to 

moderate, long-term, adverse impacts from trampling. Forest shoreline 

vegetation would generally not be affected more than a negligible or minor level 

from visitor use, including angling. Cumulative impacts would be negligible to 

moderate and adverse over the long term. 

Impairment of vegetation across the study area would not occur under 

alternative A. 
E NVIRONMENTAL C ONSEQUENCES

342 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

Impacts of Proposed Fish Stocking 

on Vegetation (Riparian Vegetation) 

In alternative A, 62 lakes are available for fishing, and of these, 52 have meadow 

vegetation in the shoreline. Not all of the vegetation is equally vulnerable to 

trampling by visitors because visitor use, fish stocking practices, and access 

differ. In alternative B, fewer lakes would be available for fishing, and a new 

category of management prescriptions, that of monitoring to determine future 

activities, would be added. 

Under alternative B, up to 20 lakes would be permanently returned to fishless 

conditions. Of these lakes, 16 do have some meadow vegetation, and all would 

experience negligible to moderate benefits from a reduction in visitor use 

attributable to fishing. Nine of the lakes are in areas that have medium or high 

levels of visitor use and/or trails leading to the lakes. Although reducing fishing 

opportunities at these lakes may benefit riparian vegetation to a greater degree 

than those where visitor use is low, it is also likely that at least some may 

experience high levels of use that are unrelated to fishing. In these cases, 

meadow shoreline vegetation may continue to experience minor or moderate 

impacts. 

As in all alternatives, the 29 currently fishless lakes would remain fishless, with 

continuing possible negligible impacts from past stocking and trampling and loss 

of lakeside vegetation.

Alternative B proposes the discontinuation of stocking or 

removal of fish in 44 lakes, as well as the restocking of 24 

of those lakes after evaluation or monitoring (refer to 

tables 5 and 10 in the “Alternatives” chapter). Twenty-one 

of the 24 lakes that may be restocked have some meadow 

vegetation around the shore that is vulnerable to trampling 

(3 of the 24 lakes have no meadow vegetation at present). 

Should the 21 lakes be restocked, impacts would not 

change from what they are now. Fourteen of the 21 lakes 

are within cross-country zones or near camps that have 

medium or high levels of visitor use, with the possibility 

of negligible to moderate impacts on meadow vegetation. 

Seven of the 21 lakes that may be restocked are within 

zones or near camps that have low visitor use and may 

experience negligible or minor impacts on meadow riparian vegetation. If the 

lakes are not restocked, negligible to moderate beneficial effects on meadow 

vegetation may occur. 

Of the 42 lakes that may potentially be available for fishing (refer to table 10), 

35 have some amount of meadow shoreline vegetation. Twenty-two of the 

35 lakes are within cross-country zones or near camps that experience medium or 

high visitor use, and impacts may remain negligible to moderate over time. The 

All reproducing fish 

would be removed

from McAlester Lake, 

and monitoring would

help determine 

whether to restock.
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 343

other 13 lakes that have meadow vegetation, and may potentially be available for 

fishing under this alternative, have fewer than 34 annual visitors in a given year 

and very little trail access. Impacts on vegetation at these 13 lakes may be 

negligible or minor. 

Negligible to moderate adverse impacts are expected for the 6 lakes that would 

continue to have fish or would be restocked and where shrub communities are 

present and meadow communities are not. It was not possible to determine if 

more resistant high-stature shrubs (such as willows) or sensitive low-lying shrubs 

(such as heather and huckleberry) are dominant at individual lakes, which is why 

the range of potential impact is broad. Forest cover is dominant at 1 lake that 

experiences high visitor use; the effects of continued fish stocking at this lake 

may be minor and adverse. 

Impacts of Lake 

Treatment Methods on Vegetation 

Natural Methods. Natural methods would be used to remove fish from 12 lakes. 

Ongoing impacts from sport fishing would continue until fishing is no longer 

satisfactory to anglers and fish are no longer present, after which time, conditions 

would likely improve. 

Mechanical Methods. Mechanical methods would be used to treat up to 8 lakes. 

One lake is proposed for spawning habitat exclusion. A 30-foot section of 

spawning habitat would be covered with rock taken from a nearby talus slope and 

moved by hand to the lake. Adverse impacts on meadow vegetation from 

covering vegetation with rock and from trampling would be minor to moderate 

and short-term. Setting gillnets and using electroshocking equipment would 

result in some trampling, although mitigation by avoiding vegetation and wading 

near the shore rather than walking through shoreline vegetation would reduce the 

impact to negligible or minor and short term. 

Chemical Methods. Chemical treatment is proposed for 19 lakes. There would 

be a negligible impact on vegetation from chemical removal of reproducing trout. 

Impacts of Other Mitigation 

Impacts of other mitigation would be similar to those under alternative A. 

Additional signs would be posted in riparian areas that were most heavily used to 

allow for recovery of vegetation. Furthermore, using an adaptive management 

approach for lakes to be evaluated would provide an opportunity to monitor the 

level of impact anglers have on vegetation, and possibly make fishery 

management decisions based at least in part on the condition of shoreline 

vegetation at a given lake. 

Cumulative Impacts 

Cumulative impacts would be similar to alternative A (negligible to moderate, 

adverse, and long term), although potentially reduced because there would be 

fewer lakes available for stocking and fishing. 
E NVIRONMENTAL C ONSEQUENCES

344 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Conclusion 

Twenty-nine of the 35 lakes in the study area where fishing would continue have 

meadow vegetation that is sensitive to trampling. Eleven of the 29 lakes are 

within cross-country zones or near camps that would continue to experience low 

visitor use, with resulting negligible to minor adverse impacts. Eighteen of the 

29 lakes are within cross-country zones or near camps that would continue to 

experience medium to high visitor use, and vegetation would experience 

negligible to moderate impacts. In addition to the 29 lakes that are currently 

fishless in alternative A, alternative B would return 20 lakes to a fishless 

condition with possible negligible to moderate benefits to shoreline meadow 

vegetation over time. Temporary negligible to moderate adverse impacts on 

shoreline vegetation from trampling related to chemical or mechanical lake 

treatments would occur, and continued fishing as a means of natural removal 

would have short-term negligible to moderate adverse impacts. Cumulative 

impacts would be negligible to moderate, adverse, and long term. 

Impairment of vegetation across the study area would not occur under 

alternative B. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Impacts of Fish Stocking 

on Vegetation (Riparian Vegetation) 

Alternative C proposes an adaptive management framework for 91 lakes, where 

11 of the 22 lakes in the Ross Lake and Lake Chelan National Recreation Areas 

may have fish, and the remaining 69 lakes, which are in the national park, either 

would remain fishless or be returned to their natural fishless condition. Of the 

other 11 lakes in the national recreation areas, 3 would remain fishless, 3 would 

have high-density reproducing fish removed, and stocking would be discontinued 

in 5 lakes. The “Alternatives” chapter provides a detailed description of 

alternative C. For more information on the 91 lakes, refer to tables 5 and 12 in 

the “Alternatives” chapter, appendix E, and “Map 2” and “Map 2 Table” located 

in the envelope that accompanied this document. 

Under alternative C, adverse impacts on riparian zone vegetation would be 

negligible to moderate in those lakes with an abundance of meadow vegetation, 

which allows for walking along the shore. All 9 lakes that would continue to 

have fish have from 20% to 58% meadow in the shoreline. The 2 lakes that 

would be evaluated for possible future stocking of fish at low densities also have 

meadow vegetation. 

As noted earlier, visitor numbers, trail access, and stock access influence the 

degree of impact. Of the 9 lakes with meadow vegetation that would be available 

for continued fishing, 5 are located in cross-country zones or are near camps that 

have low visitor use and most likely experience negligible impacts in the riparian 

zone. This would continue under alternative C. None of the 9 lakes are located in 

zones or are near camps that receive a medium level of visitation. Two of the 
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 345

Lakes that are currently 

fishless would remain 

fishless under all alternatives.
E NVIRONMENTAL C ONSEQUENCES

346 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

9 lakes, however, are located in zones or are near camps that experience high 

visitor use—impacts on meadow vegetation at these 2 lakes may continue to be 

negligible to moderate. There are 2 lakes (McAlester and Battalion) that would 

be evaluated before restocking. McAlester is located near an established 

backcountry camp that receives a high level of use—impacts on meadow 

vegetation in this area would be negligible to moderate. Battalion is located in a 

cross-country zone with very low use, and impacts on meadow vegetation would 

be negligible. 

Two of the lakes where fishing would continue have vegetation dominated by 

forest, and one lake has shoreline vegetation dominated by shrub. One of the 

lakes dominated by forest and the one lake dominated by shrub are located in 

cross-country zones or near backcountry camps that experience a low level of 

use—impacts on forest and shrub vegetation may be negligible. The other lake 

dominated by forest (100%) is located near a high-use backcountry camp—

impacts on vegetation may be negligible to moderate. All three lakes are 

accessible by stock (horses, mules, llamas). 

In this alternative C, 29 lakes (3 in the national recreation areas and 26 in the 

national park) would remain fishless, and 51 additional lakes (8 in national 

recreation areas and 43 in the national park) would become fishless. Of the 

51 lakes that would become fishless, 43 are classified as having from 2% to 76% 

meadow in the shoreline. Impacts on riparian vegetation should be monitored at 

the 2 lakes that would be evaluated prior to restocking. As angler use declines at 

the 43 lakes, there would be negligible to moderate beneficial effects on meadow 

vegetation. There are 14 lakes with shoreline meadow that are in cross-country 

zones or near camps that experience low visitor use—discontinuation of fish 

stocking or fish removal would have negligible beneficial effects on vegetation at 

these lakes. For the 19 lakes that are in cross-country zones or near camps that 

experience medium visitor use or have trail or livestock access, discontinued fish 

stocking or fish removal would result in negligible to minor beneficial impacts on 

meadow vegetation. A negligible to moderate beneficial effect would be 

expected at the 10 lakes with shoreline meadow that are in cross-country zones or 

near camps that experience high visitor use or have trail or stock access. 

Negligible impacts from past visitor use at the 29 lakes that are currently fishless 

would remain or heal in time. 

There would be negligible to moderate beneficial effects on vegetation 

dominated by shrubs at 5 lakes that would become fishless. It was not possible to 

determine if more resistant high-stature shrubs (such as willows) or sensitive 

low-lying shrubs (such as heather and huckleberry) are dominant at individual 

lakes, which is why the range of potential impact is broad. Forest cover is 

dominant at 1 lake that experiences high visitor use; the impacts of continued fish 

stocking at this lake may be minor and adverse. 

Impacts of Proposed Lake 

Treatment Methods on Vegetation 

Natural Methods. Twenty-one lakes would be treated with natural methods. 

Impacts on meadow vegetation from anglers would continue until the lakes are 

sufficiently fished out. These impacts would range from negligible to moderate, 

and depend on the factors identified earlier; however, the adverse impacts would 
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 347

be short term, and vegetation would return to more natural conditions as fishing 

declines over time. 

Mechanical Methods. Mechanical treatment is proposed for up to 10 lakes. One 

lake is proposed for spawning habitat exclusion. A 30-foot section of spawning 

habitat would be covered with rock taken from nearby talus slope and moved by 

hand to the lake. Adverse impacts on meadow vegetation from covering 

vegetation with rock and from trampling would be minor to moderate and short 

term. Setting nets and using electroshocking equipment would result in some 

trampling, although mitigation by avoiding vegetation and wading near the shore 

rather than walking through shoreline vegetation would reduce the impact to 

negligible or minor and short term. 

Chemical Method. Under alternative C, chemical treatment is proposed for 

25 lakes. There would be a negligible impact on vegetation from chemical 

removal of trout because chemicals would be applied primarily from a boat and 

would not affect vegetation. Placing and removing a boat would have some 

temporary negligible or minor site-specific impacts. 

Impacts of Other Mitigation 

Impacts of other mitigation would be the same as under alternative B. Additional 

signs would be posted in riparian areas that were most heavily used to allow for 

recovery of vegetation. Furthermore, using an adaptive management approach for 

lakes to be evaluated would provide an opportunity to monitor the level of impact 

anglers have on vegetation. 

Cumulative Impacts 

Cumulative impacts would be similar to alternative A (negligible to moderate, 

adverse, and long term), although potentially reduced because there would be 

fewer lakes available for stocking/fishing. 

Conclusion 

Alternative C would provide substantial long-term benefits to meadow and 

sensitive forest vegetation from the return of 51 additional lakes to fishless 

conditions compared to alternative A. The majority of these lakes have meadow 

vegetation, and 29 of the 51 lakes are located in cross-country zones or near 

camps that receive a medium to high level of use. To the extent this use is 

attributable to fishing and fishing-related stock use, benefits to vegetation would 

occur at these lakes. Of the 9 lakes where fishing would continue, 6 are in crosscountry zones or near camps that experience light use now, which would most 

likely continue to have negligible adverse impacts on vegetation. Three lakes are 

in cross-country zones or near camps that would continue to experience medium 

or high use, with resulting negligible to moderate adverse impacts on meadow 

vegetation. One lake may continue to experience minor or even moderate impacts 

on shoreline forest vegetation. Temporary negligible or minor adverse impacts on 

shoreline vegetation from trampling related to chemical or mechanical lake 

treatment would occur, and continued fishing as a means of natural removal 

would have short-term negligible to moderate adverse impacts. Cumulative 

impacts would be long term, negligible to moderate, and adverse. 
E NVIRONMENTAL C ONSEQUENCES

348 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Impairment of vegetation across the study area would not occur under 

alternative C.

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Alternative D proposes that 29 currently fishless lakes would remain fishless, and 

62 lakes would become fishless from discontinuing stocking or removing fish 

using natural, chemical, or natural treatment methods. The result would be 

fishless conditions in 91 lakes in the study area. The “Alternatives” chapter 

provides a detailed description of alternative D. For more information on the 91 

lakes, refer to tables 5 and 13 in the “Alternatives” chapter, appendix E, 

appendix M, and “Map 2” and “Map 2 Table” located in the envelope that 

accompanied this document. 

Impacts of Fish Stocking on 

Vegetation (Riparian Vegetation) 

Adverse impacts on the riparian zone would decline following the return of lakes 

to fishless conditions, and negligible to moderate beneficial impacts would occur 

as disturbed meadow areas recover. Of the 62 lakes that would remain fishless or 

become fishless, 52 are classified as having from 2% to 76% meadow in the 

shoreline. As noted earlier, meadow vegetation may be particularly sensitive 

to trampling. 

There are 20 lakes with shoreline meadow that are located in cross-country zones 

or near camps that currently experience low visitor use. Discontinuing stocking 

and removing fish is expected to have negligible beneficial impacts on vegetation 

at these lakes. For the 19 lakes that are in cross-country zones or near camps that 

currently experience medium visitor use or have trail or stock (horses, mules, 

llamas) access, discontinued fish stocking and fish removal may result in 

negligible to minor beneficial impacts on meadow vegetation. Negligible to 

moderate beneficial impacts are expected at the 13 lakes with shoreline meadow 

that are in cross-country zones or near camps that experience high visitor use or 

have trail or stock access. Visitor use data is missing for one of the lakes that has 

shoreline meadow cover. 

Vegetation at the 29 lakes that are currently fishless would continue to 

experience negligible adverse impacts from past visitor use but would be 

undetectable compared to natural conditions in time. 

Impacts of Lake Treatment 

Methods on Vegetation 

Under alternative D, discontinued stocking and fish removal are proposed for 

62 lakes. 

Natural Methods. Natural treatment is proposed for 26 lakes. Impacts on 

meadow vegetation from anglers would continue until the lakes are sufficiently 

fished out. These impacts would range from negligible to moderate and depend 

on the factors identified earlier; however, impacts would be short term, and 
Vegetation 

ENVIRONMENTAL IMPACT STATEMENT 349

vegetation would return to more natural conditions over time as visitor use 

related to fishing declines. 

Mechanical Methods. Mechanical treatment is proposed for 11 lakes. One lake 

is proposed for spawning habitat exclusion. A 30-foot section of spawning 

habitat would be covered with rock taken from nearby talus slope and moved by 

hand to the lake. Adverse impacts on meadow vegetation from covering 

vegetation with rock and from trampling would be minor to moderate and short 

term. Setting nets and using electroshocking equipment would result in some 

trampling, although mitigation by avoiding vegetation and wading near the shore 

rather than walking through shoreline vegetation would reduce the impact to 

negligible or minor and short term. 

Chemical Method. Chemical treatment is proposed for 25 lakes. Adverse 

impacts would be negligible and short term because chemicals would be applied 

from a boat. Dragging a boat across meadow vegetation would have temporary, 

minor impacts, although these impacts would be easily mitigated by carrying 

boats. 

Impacts of Other Mitigation 

Impacts of other mitigation would be the same as under alternative B. Additional 

signs would be posted in riparian areas that were most heavily used to allow for 

recovery of vegetation. Furthermore, the adaptive management plans for lakes set 

for evaluation provide an opportunity to monitor the level of impact anglers have 

on vegetation. 

Cumulative Impacts 

Cumulative impacts would be similar to alternative A (negligible to minor, 

adverse, and long term), although reduced because there would be no lakes 

available for stocking/fishing. 

Conclusion 

Under alternative D, 62 additional lakes would be returned to fishless conditions 

compared to alternative A. Vegetation at these lakes would experience overall 

beneficial impacts under alternative D. The degree of benefit would range from 

negligible to moderate and would depend on the level of visitor use, access, 

sensitivity of the vegetation, and other factors. The majority of these lakes have 

meadow vegetation. If high visitor use, stock use, and trail use are related to 

fishing, a decline in fishing opportunity would offer substantial benefits to this 

more sensitive vegetative community. Temporary negligible or minor adverse 

impacts on shoreline vegetation from trampling related to chemical or 

mechanical lake treatment would occur, and continued fishing as a means of 

natural removal would have short-term negligible to moderate adverse impacts. 

Cumulative impacts would be negligible to moderate, adverse, and long term. 

Impairment of vegetation across the study area would not occur under 

alternative D. 
350 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

CULTURAL RESOURCES 

GUIDING REGULATIONS AND POLICIES 

Federal actions that have the potential to affect cultural resources are subject to a 

variety of laws. 

The National Historic Preservation Act (1966, as amended; NHPA) is often the 

principal legislative authority for managing cultural resources associated with 

NPS projects. Section 106 of the NHPA requires all federal agencies to consider 

the effects of their actions on cultural resources determined eligible for inclusion 

in the National Register of Historic Places (National Register). Such resources 

are termed “historic properties.” Agreement on mitigation of effects to historic 

properties is reached through consultation with the State Historic Preservation 

Officer; Tribal Historic Preservation Officer, if applicable; and, as required, the 

Advisory Council on Historic Preservation (Advisory Council). In addition, the 

NHPA requires that federal agencies take actions to minimize harm to historic 

properties that would be adversely affected by a federal undertaking. Section 110 

of the NHPA, among other things, charges federal agencies with the 

responsibility for establishing preservation programs for identification, 

evaluation, and nomination of historic properties to the NRHP. 

Other important laws and regulations designed to protect cultural resources are 

Native American Graves Protection and Repatriation Act (NAGPRA), 

1990 

American Indian Religious Freedom Act (AIRFA), 1978 

National Environmental Policy Act (NEPA), 1969 

Archeological Resources Protection Act (ARPA), 1979 

Executive Order 11593, 1971 

In addition, the NPS is charged with protection and management of cultural 

resources in its custody. This is furthered through the implementation of NPS-28:

Cultural Resources Management Guidelines (NPS 1997), NPS Management 

Policies (NPS 2001a), and the 1995 Service-wide Programmatic Agreement with 

the Advisory Council and the National Conference of State Historic Preservation 

Officers. These documents charge NPS managers with avoiding, or minimizing to 

the greatest degree practicable, adverse impacts on park resources and values. 

Although the NPS has the discretion to allow certain impacts in parks, that 

discretion is limited by the statutory requirement that park resources and values 

remain unimpaired, unless a specific law directly provides otherwise. 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 351

METHODOLOGY AND ASSUMPTIONS

The NPS categorizes cultural resources by the following categories: 

archeological resources, cultural landscapes, historic structures, museum objects, 

and ethnographic resources. The actions proposed in the alternatives would have 

minimal impact on museum objects, and hence, they are not discussed further. A 

review of reference materials regarding cultural resources in the North Cascades 

Complex, as well as communications with NPS staff, were completed to identify 

and evaluate potential impacts on cultural resources located in the study area. 

The North Cascades Complex contains a number of cultural resources that are 

eligible or included in the National Register (see the “Cultural Resources” 

section in the “Affected Environment” chapter). 

CEQ regulations require assessment of cumulative impacts in the 

decision-making process for federal projects. Cumulative impacts are defined as 

“the impact on the environment which results from the incremental impact of the 

action when added to other past, present, and reasonably foreseeable future 

actions regardless of what agency (federal or nonfederal) or person undertakes 

such other actions” (40 CFR 1508.7). Cumulative impacts on cultural resources 

over time can include total loss of sites or parts of sites due to development, soil 

erosion, or lack of appropriate maintenance; loss of integrity and interpretive 

value; and the gradual loss of the cultural resource base within a park. 

Cumulative impacts are considered for both the no-action and action alternatives. 

The descriptions of effects on cultural resources that are presented in this section 

are intended to comply with the requirements of both NEPA and section 106 of 

the NHPA. In accordance with the Advisory Council’s regulations implementing 

section 106 (36 CFR Part 800, Protection of Historic Properties), impacts on 

cultural resources were identified and evaluated by (1) determining the area of 

potential effects; (2) identifying cultural resources present in the area of potential 

effects that are either listed in or eligible to be listed in the National Register; 

(3) applying the criteria of adverse effect to affected cultural resources either 

listed in or eligible to be listed in the National Register; and (4) considering ways 

to avoid, minimize, or mitigate adverse effects. 

Under the Advisory Council’s regulations, a determination of either adverse 

effect or no adverse effect must also be made for affected National Registereligible cultural resources. An adverse effect occurs whenever an impact alters, 

directly or indirectly, any characteristic of a cultural resource that qualifies it for 

inclusion in the National Register (for example, diminishing the integrity of the 

resource’s location, design, setting, materials, workmanship, feeling, or 

association). Adverse effects also include reasonably foreseeable effects caused 

by the proposal that would occur later in time, be farther removed in distance, or 

be cumulative (36 CFR 800.5, Assessment of Adverse Effects). A determination 

of no adverse effect means there is an effect, but the effect would not diminish, in 

any way, the characteristics of the cultural resource that qualify it for inclusion in 

the National Register. 

CEQ regulations and Director’s Order 12: Conservation Planning, 

Environmental Impact Analysis and Decision-making (NPS 2001b) also call for a 

discussion of the appropriateness of mitigation, as well as an analysis of how 
E NVIRONMENTAL C ONSEQUENCES

352 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

effective the mitigation would be in reducing the intensity of a potential impact; 

for example, reducing the intensity of an impact from major to moderate or 

minor. Any resultant reduction in intensity of impact due to mitigation, however, 

is an estimate of the effectiveness of mitigation under NEPA only. It does not 

suggest that the level of effect as defined by section 106 is similarly reduced. 

Cultural resources are nonrenewable resources, and adverse effects generally 

consume, diminish, or destroy the original historic materials or form, resulting in 

a permanent loss in the integrity of the resource that can never be recovered. 

Therefore, although actions determined to have an adverse effect under section 

106 may be mitigated, the effect remains adverse. 

The “Section 106 Summary” follows the cultural resources impact analyses, and 

a section 106 statement is included in the conclusion statements for each cultural 

resource evaluated. The section 106 summary is intended to meet the 

requirements of section 106 and is an assessment of the effect of the undertaking 

(implementation of the alternative) on cultural resources, based on the criterion 

of effect and criteria of adverse effect found in the Advisory Council’s 

regulations. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

For the purpose of this analysis, the “Area of Potential Effect” is defined as the 

North Cascades Complex. 

D EFINITIONS OF I NTENSITY L EVELS

Archeological Resources 

Negligible: Impact is at the lowest levels of detection – barely measurable 

with no perceptible consequences, either adverse or beneficial. 

For purposes of section 106, the determination of effect would 

be no adverse effect. 

Minor: Beneficial effect – maintenance and preservation of a site(s). For 

purposes of section 106, the determination of effect would be no 

adverse effect. 

Adverse impact – disturbance of a site(s) results in little, if any, 

loss of integrity. For purposes of section 106, the determination 

of effect would be no adverse effect. 

Moderate: Beneficial effect – stabilization of a site(s). For purposes of 

section 106, the determination of effect would be no adverse 

effect. 

Adverse impact – disturbance of a site(s) results in loss of integrity. For 

purposes of section 106, the determination of effect would be adverse effect. A 

memorandum of agreement is executed between the NPS and applicable State or 

Tribal Historic Preservation Officer and, if necessary, the Advisory Council in 

accordance with 36 CFR 800.6(b). The mitigation measures identified in the 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 353

memorandum of agreement would reduce the intensity of impact under NEPA 

from major to moderate. 

Major: Beneficial effect – active intervention to preserve a site(s). For 

purposes of section 106, the determination of effect would be no 

adverse effect. 

Adverse impact – disturbance of a site(s) results in loss of 

integrity. For purposes of section 106, the determination of effect 

would be adverse effect. The NPS and applicable State or Tribal 

Historic Preservation Officer are unable to negotiate and execute 

a memorandum of agreement in accordance with 36 CFR 

800.6(b). 

Historic Structures 

Negligible: Impact(s) is at the lowest levels of detection – barely measurable 

with no perceptible consequences, either adverse or beneficial. 

For purposes of section 106, the determination of effect would 

be no adverse effect. 

Minor: Beneficial effect – stabilization/preservation of features in 

accordance with the Secretary of the Interior’s Standards for the 

Treatment of Historic Properties. For purposes of section 106, 

the determination of effect would be no adverse effect.

Adverse impact – impact would alter a feature(s) of a structure 

but would not diminish the overall integrity of the resource. For 

purposes of section 106, the determination of effect would be no 

adverse effect. 

Moderate: Beneficial effect – rehabilitation of a structure in accordance 

with the Secretary of the Interior’s Standards for the Treatment 

of Historic Properties. For purposes of section 106, the 

determination of effect would be no adverse effect. 

Adverse impact – impact would alter a feature(s) of the 

structure, diminishing the overall integrity of the resource. For 

purposes of section 106, the determination of effect would be 

adverse effect. A memorandum of agreement would be executed 

between the NPS and applicable State or Tribal Historic 

Preservation Officer and, if necessary, the Advisory Council in 

accordance with 36 CFR 800.6(b). The mitigation measures 

identified in the memorandum of agreement would reduce the 

intensity of impact under NEPA from major to moderate. 

Major: Beneficial effect – restoration of a structure in accordance with 

the Secretary of the Interior’s Standards for the Treatment of 

Historic Properties. For purposes of section 106, the 

determination of effect would be no adverse effect. 
E NVIRONMENTAL C ONSEQUENCES

354 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Adverse impact – impact would alter a feature(s) of the 

structure, diminishing the overall integrity of the resource. For 

purposes of section 106, the determination of effect would be 

adverse effect. The NPS and applicable State or Tribal Historic 

Preservation Officer are unable to negotiate and execute a 

memorandum of agreement in accordance with 36 CFR 800.6(b). 

Cultural Landscapes 

Negligible: Impact(s) is at the lowest levels of detection – barely perceptible 

and not measurable. For purposes of section 106, the 

determination of effect would be no adverse effect. 

Minor: Beneficial effect – preservation of landscape patterns and 

features in accordance with the Secretary of the Interior’s 

Standards for the Treatment of Historic Properties with 

Guidelines for the Treatment of Cultural Landscapes. For 

purposes of section 106, the determination of effect would be no 

adverse effect. 

Adverse impact – impact(s) would alter a pattern(s) or 

feature(s) of the cultural landscape but would not diminish the 

overall integrity of the landscape. For purposes of section 106, 

the determination of effect would be no adverse effect. 

Moderate: Beneficial effect – rehabilitation of a landscape or its patterns 

and features in accordance with the Secretary of the Interior’s 

Standards for the Treatment of Historic Properties with 

Guidelines for the Treatment of Cultural Landscapes. For 

purposes of section 106, the determination of effect would be no 

adverse effect. 

Adverse impact – impact(s) would alter a pattern(s) or 

feature(s) of the cultural landscape, diminishing the overall 

integrity of the landscape. For purposes of section 106, the 

determination of effect would be adverse effect. A memorandum 

of agreement is executed between the NPS and applicable State 

or Tribal Historic Preservation Officer and, if necessary, the 

Advisory Council in accordance with 36 CFR 800.6(b). The 

mitigative measures identified in the memorandum of agreement 

reduce the intensity of impact under NEPA from major to 

moderate. 

Major: Beneficial effect – restoration of a landscape or its patterns and 

features in accordance with the Secretary of the Interior’s 

Standards for the Treatment of Historic Properties with 

Guidelines for the Treatment of Cultural Landscapes. For 

purposes of section 106, the determination of effect would be no 

adverse effect. 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 355

Adverse impact – impact(s) would alter a pattern(s) or 

feature(s) of the cultural landscape, diminishing the overall 

integrity of the resource. For purposes of section 106, the 

determination of effect would be adverse effect. The NPS and 

applicable State or Tribal Historic Preservation Officer are 

unable to negotiate and execute a memorandum of agreement in 

accordance with 36 CFR 800.6(b). 

Ethnographic Resources 

Some places of traditional cultural use may be eligible for inclusion in the 

National Register as traditional cultural properties because of their association 

with cultural practices or beliefs of a living community that (a) are rooted in that 

community's history and (b) are important in maintaining the continuing cultural 

identity of the community (National Register Bulletin, Guidelines for Evaluating 

and Documenting Traditional Cultural Properties). 

Negligible: Impact(s) would be barely perceptible and would neither alter 

resource conditions, such as traditional access or site 

preservation, nor alter the relationship between the resource and 

the affiliated group’s body of practices and beliefs. For purposes 

of section 106, the determination of effect on traditional cultural 

properties would be no adverse effect. 

Minor: Beneficial effect – would allow access to and/or accommodate a 

group’s traditional practices or beliefs. For purposes of section 

106, the determination of effect on traditional cultural properties 

would be no adverse effect.

Adverse impact – impact(s) would be slight but noticeable but 

would neither appreciably alter resource conditions, such as 

traditional access or site preservation, nor alter the relationship 

between the resource and the affiliated group’s body of practices 

and beliefs. For purposes of section 106, the determination of 

effect on traditional cultural properties would be no adverse 

effect. 

Moderate: Beneficial effect – would facilitate traditional access and/or 

accommodate a group’s practices or beliefs. For purposes of 

section 106, the determination of effect on traditional cultural 

properties would be no adverse effect.

Adverse impact – impact(s) would be apparent and would alter 

resource conditions. Something would interfere with traditional 

access, site preservation, or the relationship between the resource 

and the affiliated group’s practices and beliefs, even though the 

group’s practices and beliefs would survive. For purposes of 

section 106, the determination of effect on traditional cultural 

properties would be adverse effect. 
E NVIRONMENTAL C ONSEQUENCES

356 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Major: Beneficial effect – would encourage traditional access and/or 

accommodate a group’s practices or beliefs. For purposes of 

section 106, the determination of effect on traditional cultural 

properties would be no adverse effect.

Adverse impact – impact(s) would alter resource conditions. 

Something would block or greatly affect traditional access, site 

preservation, or the relationship between the resource and the 

affiliated group’s body of practices and beliefs, to the extent that 

the survival of a group’s practices and/or beliefs would be 

jeopardized. For purposes of section 106, the determination of 

effect on traditional cultural properties would be adverse effect.

All Cultural Resources 

Impairment. The action would contribute substantially to the deterioration of 

cultural resources in the North Cascades Complex. In addition, any adverse 

major impacts on the North Cascades Complex’s resources and values would 

contribute to deterioration of cultural resources and values to the extent 

that the purpose of the North Cascades Complex would not be fulfilled as 

established in its enabling legislation 

affect resources key to the natural or cultural integrity or opportunities 

for enjoyment in the North Cascades Complex 

affect the resource whose conservation is identified as a goal in the 

General Management Plan (NPS 1988b) or other planning documents 

for the North Cascades Complex 

IMPACTS COMMON TO ALL ALTERNATIVES 

The potential impacts on archeological resources and mitigation measures 

common to all alternatives are addressed below. For this plan/EIS, archeological 

resources, historic structures, ethnographic resources, and cultural landscapes are 

analyzed. A programmatic agreement, as defined in 36 CFR 800.14(b), is 

designed to address complex federal project situations (for example, when effects 

on historic properties cannot be fully determined prior to approval of 

undertaking). A programmatic agreement would be implemented, if necessary. 

Under all alternatives, management actions (fish stocking and/or removal) at 

many of the mountain lakes would result in varying degrees of pedestrian-related 

ground disturbance in the North Cascades Complex (see tables 4 and 5). 

Pedestrian access to these lakes by management crews would be via existing 

roads and trails or cross-country hiking. Crews would be small (1–2 people), and 

short-term camping would occur. Work around shorelines would be necessary 

where fragile vegetation and soils would be disturbed. All of these actions have 

the potential for soil disturbance, which would uncover or damage archeological 

resources. 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 357

Several lakes (less than 10) recommended for fish management actions, and 

access routes (trails) serving these and other lakes proposed for management 

actions, have been identified as particularly sensitive regarding the presence and 

nature of cultural resources. (Because of the sensitive nature of these resources, 

their location is not publicly available information.) 

In general, ground disturbance has the potential to result in adverse impacts of 

unknown intensity on recorded and unrecorded archeological resources in these 

areas. Depending on the activity, mitigation measures designed to reduce ground 

disturbance would be implemented (see appendix I for the current and proposed 

mitigation measures. 

In addition to the mitigation measures identified in appendix I, the following 

measures may be necessary: 

Surveys by professional cultural resource specialists would proceed any 

proposed ground disturbance. 

If cultural resources are inadvertently unearthed/disturbed during 

proposed activities, all work in the immediate vicinity would be halted 

until the resource would be appropriately evaluated and mitigated, if 

necessary. 

Crews would be provided with fundamental training regarding the 

sensitivity of archeological resources and the need to protect them, as 

well as instructing them to report any newly discovered cultural resources 

to the park archeologist. 

Evaluation of cultural resources in these identified sensitive areas to 

determine National Register eligibility would be a significant aid in 

avoiding adverse impacts on historic properties. Where 

documented/recorded sites exist, the monitoring of the areas where 

ground disturbance is proposed would further mitigate any adverse 

impacts on archeological resources. 

For most lakes, these measures would likely mitigate potential adverse impacts 

from fish management activities to archeological resources to negligible to minor 

and site specific. 

The use of helicopters (and associated landing pads) to transport fish removal 

equipment to lakes has the potential to create negligible to minor, short-term, 

adverse visual impacts on cultural landscapes in the North Cascades Complex. 
E NVIRONMENTAL C ONSEQUENCES

358 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A (no action) would continue current management of the 91 lakes in 

the study area. The “Alternatives” chapter provides a detailed description of 

alternative A. For more information on the 91 lakes, refer to table 5 and figure 4 

in the “Alternatives” chapter and appendix E. 

Archeological Resources. It is estimated that approximately 1,000 visitors 

engaged in sport fishing in 2003 at the mountain lakes in the study area (see the 

“Visitor Use and Experience” section in this chapter). The continuation of 

existing sport fishing activities involves the use of the study area by anglers who 

often bring in stock (horses, mules, llamas) and camp overnight for an average of 

two days per visit (NPS, R. Zipp, pers. comm., 2003), all of which results in 

ground disturbance. Designated backcountry overnight use areas and camps are 

shown on “Map 2” and the “Map 2 Table” located in the envelope that 

accompanied this document. Adverse impacts on archeological resources of 

unknown intensity are possible as a result. Of particular concern are those 

resources that have not yet been identified, recorded, and protected by the NPS. 

Additional visitor educational information and scheduled monitoring of sensitive 

areas would aid in mitigating potential adverse effects to negligible to minor, 

over the long term. 

Historic Structures. This alternative would probably involve the highest number 

of anglers, many of whom would spend a night or two in the backcountry where 

a number of historic structures are known to exist. 

Consequently, a slightly higher likelihood for adverse impacts 

(such as vandalism) on historic structures exists than under the 

other three alternatives. The potential impact intensity on 

historic structures is unknown but is likely not higher than 

negligible to minor and site specific given the small number of 

anglers visiting the areas where structures exist. Systematic 

and periodic monitoring of resource conditions and additional 

education of backcountry users (possibly through backcountry 

permit issuance process) would likely reduce this effect to 

negligible. 

Cultural Landscapes. Twenty-four cultural landscapes have been identified in 

the North Cascades Complex; five have been determined eligible for inclusion in 

the National Register (see the “Affected Environment” chapter). One designated 

cultural landscape exists at a lake that has been identified as sensitive regarding 

cultural resources (NPS, J. Kennedy, pers. comm., 2004). This lake and the 

associated designated cultural landscape currently sustain some of the highest 

visitor levels in the North Cascades Complex. This particular cultural landscape 

is believed important because of its mining-related historic structure, features, 

and artifacts. The continuation of current levels of fishing activities proposed 

under this alternative would likely result in minor, site-specific adverse impacts 

on this designated cultural landscape. Periodic and systematic minor monitoring 

of the resource would further reduce impacts. 

Backcountry 

homesteads are part

of the cultural

landscape of the 

North Cascades 

Complex.
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 359

This alternative would continue current fishery management practices and angler 

use. Such activities would result in possible elements of a cultural landscape 

being inadvertently impacted by physical changes such as the creation of social 

trails, modification of historic structures, and artifact removal. These activities 

would result in adverse impacts of unknown intensity, particularly where cultural 

landscapes have not been inventoried, evaluated, and appropriately protected. For 

any cultural landscape that is determined to be at risk of impact as a result of this 

alternative, mitigation measures may be necessary to avoid adverse impacts on 

historic properties. Mitigation actions (such as systematic recordation, additional 

cultural resource inventory, National Register eligibility determination, and 

increased visitor information) would reduce impacts on cultural landscape 

resources to site specific to localized and minor in intensity. Periodic and 

systematic monitoring of resource conditions and additional education of 

backcountry users (possibly through backcountry permit issuance process) would 

likely reduce this potential impact further. 

Ethnographic Resources. Because no ethnographic resources have been 

documented in the North Cascades Complex, it is unlikely that impacts would 

occur as a result of the no-action alternative. It is assumed that, should such 

impacts occur, communications among the NPS, affected Tribes, and the State 

Historic Preservation Officer would be initiated, and any adverse effects would 

be mitigated to negligible through a cooperative agreement. 

Cumulative Impacts 

As is true under all alternatives, a number of cultural resources have undoubtedly 

sustained adverse impacts from natural and human forces over the lengthy period 

of human occupation of the area. Because the majority of the North Cascades 

Complex has not been formally inventoried for cultural resources, any 

unidentified resources, especially those archeological resources exposed on or 

located near the surface, would be particularly vulnerable to human and natural 

impacts. Cumulative natural impacts (erosion, general weathering,) and human 

impacts (inadvertent ground disturbance, vandalism, artifact collection, digging) 

that result in resource loss are expected to continue, and possibly increase, 

creating adverse impacts of unknown intensity on cultural resources. Ultimately, 

the resource base would be diminished, resulting in an incomplete historical 

record and likely errors in cultural interpretation as a result. The eventual 

completion of a North Cascades Complex-wide cultural resource inventory 

designed to identify/protect historic properties would benefit cultural resources in 

the region. 

Dam and reservoir construction during the 20th century, along with construction 

of related hydroelectric facilities (including the company towns of Newhalem 

and Diablo), likely resulted in major cumulative adverse impacts on cultural 

resources that continue today. Filling of reservoirs (Ross, Diablo, and Gorge 

lakes) undoubtedly inundated an unknown number of prehistoric and historic 

cultural resources. Archeological sites are known to currently exist in drawdown 

zones of Lake Chelan and Ross Lake. It is likely that the degradation of recorded 

and unrecorded sites along shorelines and drawdown zones as a result of wave 

action, changing reservoir levels, and recreational activity creates ongoing 

negligible to major adverse site-specific impacts on cultural resources (depending 
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360 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

on the resource). The inventory and appropriate mitigation of these vulnerable 

resources would be of benefit to these resources. 

Ongoing adverse impacts on cultural resources from park visitors other than 

anglers (hikers/campers/climbers) also exist within the North Cascades Complex. 

Archeological resources are particularly vulnerable to ground disturbance (see 

“Impacts Common to All Alternatives” in this section). Cultural landscapes can 

be adversely affected by a variety of recreational uses. For instance, visual 

impacts (such as social trails or road and facility construction) can alter 

character-defining features. Historic resources are exposed to potential impacts of 

vandalism and alteration, to name two, which can alter their integrity and 

significance. In general, these cumulative adverse impacts on cultural resources 

are of unknown intensity and scope because so little of the area has been 

inventoried and evaluated. Periodic and systematic monitoring of known resource 

conditions by the NPS likely aids in mitigating adverse impacts to known cultural 

resources, possibly to the negligible to minor and site-specific level. 

Of the numerous lakes and trails used recreationally, several have been identified 

as sensitive regarding cultural resources. In fact, many of these sensitive lake and 

trail areas currently experience some of the highest levels of visitor use in the 

North Cascades Complex, making cultural resources in these areas even more 

vulnerable to potential cumulative adverse impacts. As is the case with many of 

the mountain lakes, at least one of these sensitive lake areas requires some crosscountry hiking to access it, likely resulting in ground disturbance and other 

human impacts in areas where cultural resources have not been inventoried. This 

activity creates the potential for visitors to encounter, if only inadvertently, 

previously unrecorded and unprotected cultural resources, resulting in possible 

adverse impacts of unknown intensity. For these sensitive areas, further 

mitigation measures may be necessary to avoid adverse impacts on historic 

properties (for example, National Register eligibility evaluations of known sites, 

additional cultural resource inventory, and increased visitor information) (see the 

discussion of ground-disturbance potential under “Impacts Common to All 

Alternatives” that appeared earlier in this section). Implementation of such 

measures would likely result in negligible to minor, site-specific impacts on 

cultural resources within these sensitive areas. 

Conclusion 

Alternative A would not change the number of lakes for fishing or the number of 

anglers using them over the long term. Potential adverse impacts of unknown 

intensity on archeological resources would be mitigated to negligible to minor. 

Mitigation would also help keep impacts on historic structures from exceeding 

minor levels. Potential impacts on cultural landscapes would be mitigated to no 

greater than minor. No impacts on ethnographic resources are anticipated. For the 

purpose of compliance with section 106 of the National Historic Preservation 

Act, there would be no adverse effect on cultural resources. Adverse cumulative 

impacts would range from negligible to minor over the long term. 

Impairment of cultural resources across the study area would not occur under 

alternative A. 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 361

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative is to eliminate or reduce the density of 

reproducing fish from certain mountain lakes in the study area. 

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Archeological Resources. The adverse effects described in alternative A would 

be similar under alternative B. Impacts on archeological resources of unknown 

intensity as a result of sport fishing activities would occur. With mitigation, these 

adverse site-specific impacts would be reduced to negligible to minor over the 

long term. 

Alternative B proposes fish removal by a variety of means. Lake treatment 

methods include natural (cease stocking, increase fishing limits), mechanical (gill 

netting/electrofishing, fyke nets, trapping, and spawning habitat exclusion), and 

chemical (piscicide such as antimycin). NPS implementation of all these 

techniques would result in potential ground disturbance with impacts on 

archeological resources as described earlier in the “Impacts Common to All 

Alternatives” section. Negligible to minor archeological resource impacts, with 

proposed mitigation, would occur over the long term. 

The use of mechanical and chemical means of fish removal would require the use 

of transport helicopters and landing pads. Many lakes would have adequate 

natural landing areas that would not require ground disturbance (such as leveling) 

for preparation (NPS, R. Mierendorf, pers. comm., 2004). In these cases, it is 

unlikely that cultural resources would be impacted; however, review by a cultural 

resource professional of the surface area prior to its use as a landing pad would 

ensure this. In those cases where ground preparation is required for helicopter 

landing, there would be potential for adverse impacts of unknown intensity to 

archeological resources. The surface survey and monitoring of the ground 

disturbance of these areas by a cultural resource professional would mitigate 

these site-specific impacts to negligible to minor over the long term. 

Historic Structures. Fewer anglers, but more fishery management actions would 

occur under alternative B. The potential impact intensity under alternative B for 

historic structures is unknown but is likely not higher than negligible to minor 

and site specific given the small number of anglers visiting the area. Periodic and 

systematic monitoring of resource conditions and additional education of 

backcountry users (possibly through backcountry permit issuance process) would 

likely reduce this potential impact further. 

Cultural Landscapes. The nature of angling and related activities would remain 

similar to that currently observed, with many anglers typically spending a night 

or two in the backcountry where a number of cultural landscape resources exist. 

Due to the slightly fewer numbers of anglers, alternative B would result in a 
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362 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

modest reduction in the likelihood of adverse impacts on cultural landscapes 

when compared to alternative A. The intensity of potential impacts on cultural 

landscapes under alternative B is unknown because so many identified resources 

remain unevaluated. For any cultural landscape that is determined to be at risk of 

impact as a result of the implementation of alternative B, mitigation measures 

may be necessary to avoid adverse impacts on historic properties (refer to the 

discussion under “Impacts Common to All Alternatives” in this section and 

“Appendix I: Mountain Lakes Fishery Current and Proposed Mitigation 

Practices”). 

Impacts on the designated cultural landscapes that were noted in alternative A 

would be minor in alternative B. 

Ethnographic Resources. Ethnographic resources have not been documented in 

the North Cascades Complex, so it is unlikely that impacts would occur as a 

result of alternative B. It is assumed that, should such impacts occur, 

communications among the NPS, affected Tribes, and the State Historic 

Preservation Office would be initiated, and any adverse effects would be 

mitigated to negligible through a cooperative agreement. 

The proposed use of chemical methods for fish removal would temporarily affect 

water quality, possibly an issue for Native Americans who may use some of these 

water bodies for traditional contemporary purposes (ceremonial bathing, vision 

quests). Depending on the location, amount, and type of chemicals used, such 

actions would result in adverse impacts of unknown intensity to such 

ethnographic resources. Impacts would be mitigated to negligible through an 

agreement among the NPS, affected Tribes, and the State Historic Preservation 

Office regarding when and where such removal methods would be used and in a 

manner that would not adversely affect these resources. 

Cumulative Impacts 

Cumulative impacts would be similar to those described under alternative A and 

would range from adverse negligible to minor over the long term. 

Conclusions 

Possible impacts on archeological resources that would result from preparation of 

mechanical fish removal equipment and helicopter use (and associated landing 

pads adjacent to lakes) to transport the equipment would be mitigated to 

negligible to minor through survey and monitoring prior to use. Possible adverse 

impacts on historic structures are of unknown magnitude but would not likely 

exceed negligible to minor. Potential impacts on identified cultural landscapes 

would be mitigated to no greater than minor. The temporary water-quality 

degradation from chemicals used to remove fish would potentially result in 

adverse impacts of unknown intensity to ethnographic resources used by Native 

Americans for traditional purposes. Such impacts would be mitigated to 

negligible through an agreement with the NPS, affected Tribes, and the State 

Historic Preservation Office regarding the timing of management activities and 

locations of specific areas that should be avoided. For the purpose of compliance 

with section 106 of the National Historic Preservation Act, there would be no 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 363

adverse effect on cultural resources. Adverse cumulative impacts would range 

from negligible to minor over the long term. 

Impairment of cultural resources across the study area would not occur under 

alternative B. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Under alternative C, 9 lakes in Ross Lake and Lake Chelan National Recreation 

Areas would have fish and 2 lakes would be evaluated for restocking. Eleven 

other lakes in the national recreation areas would remain fishless or be returned 

to fishless conditions. The remaining 69 lakes (which are in the national park) 

would be returned to their natural fishless conditions or would remain fishless. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Archeological Resources. In the long term, and when compared to alternative A, 

sport fishing activities would be further reduced under alternative C, resulting in 

negligible impacts on archeological resources in general. Alternative C also 

proposes that one lake identified as sensitive be returned to its natural fishless 

state. This lake area and its trail access contain a substantial number of 

archeological resources. In the long term, this reduction in the number of anglers 

to this lake and its access route represents a long-term benefit for cultural 

resources. 

Historic Structures. Activities would involve a small number of anglers 

spending a night or two in the backcountry where historic structures are known to 

exist. With fewer anglers, the likelihood for adverse impacts (such as vandalism) 

on historic structures would be further reduced, likely to the negligible level in 

the long term. In addition, one lake that has been identified as sensitive, 

particularly for historic resources, would revert to a fishless condition under this 

alternative. This lake sustains some of the highest visitor numbers of all 91 lakes 

in the study area. Reducing anglers at the lake and its access trail would notably 

reduce risk of adverse impacts, a benefit to the historic resources around this 

lake. 

Cultural Landscapes. As is the case under all alternatives, a number of cultural 

landscapes remain unevaluated in the study area. This alternative would result in 

fewer numbers of anglers than under alternatives A. Fishing activities would 

involve a small number of anglers spending a night or two in the backcountry 

where cultural landscapes have been identified. With fewer anglers, the 

likelihood of adverse impacts on cultural landscapes would be further reduced, 

but of unknown intensity. For any cultural landscape that may be determined at 

risk of adverse impacts as a result of this alternative, mitigation measures (such 

as systematic recordation, additional cultural resource inventory, National 

Register eligibility evaluation, and increased visitor information) would aid in 
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364 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

reducing impacts on cultural landscapes to site specific to localized and 

negligible to minor in intensity. 

More specifically, one designated cultural landscape exists at a lake that has been 

identified as sensitive regarding cultural resources, particularly historic resources 

(NPS, J. Kennedy, pers. comm., 2004). This lake would revert to a fishless 

condition under alternative C. The lake area and its associated cultural landscape 

currently sustain some of the highest visitor numbers of all 91 lakes in the study 

area. Elimination of anglers in this area would notably reduce risk of adverse 

impacts, a benefit to cultural landscape resources around this lake. 

Ethnographic Resources. Impacts on ethnographic resources under alternative 

C would be similar to those described in alternative B. 

Cumulative Impacts 

The removal of fish or maintaining fishless conditions in 80 mountain lakes in 

the study area would ultimately reduce human activity related to fishing and, 

over the long term, fishery management, thereby reducing ground disturbance to 

a greater degree than under alternative A. Over time, fewer visitors (anglers, fish 

management crews) to a number of the lakes and their access trails would result 

in a cumulative, localized, long-term benefit for cultural resources by reducing 

exposure to human activity. 

Conclusions 

The impact of reduced sport-fishing opportunities would result in negligible 

impacts on archeological resources in general, with beneficial effects as a result 

of the return of one lake identified as sensitive to a fishless state. Adverse 

impacts on historic structures are likely to be negligible; the elimination of 

fishing at one particularly sensitive lake would result in a benefit to historic 

structures. Cultural landscapes in the study area may incur no greater than minor 

adverse impacts; in one case, a benefit to the resources would be realized. 

Impacts on ethnographic resources would likely be mitigated to negligible. For 

the purpose of compliance with section 106 of the National Historic Preservation 

Act, there would be no adverse effect on cultural resources. There would be 

cumulative beneficial effects for cultural resources from reduced human activity 

at a number of mountain lakes. 

Impairment of cultural resources across the study area would not occur under 

alternative C. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

The goal of this alternative is to remove fish from (or maintain as fishless) all 

91 lakes in the study area. The “Alternatives” chapter provides a detailed 

description of alternative D. For more information on the 91 lakes, refer to 

tables 5 and 13 in the “Alternatives” chapter and appendix E. 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 365

Archeological Resources. All sport fishing would be eliminated under this 

alternative. While anglers make up only a small number of visitors to the North 

Cascades Complex, the presence of fish management crews would also be 

eliminated in the long term, reducing ground-disturbing activities further. 

Reduction in human activity would be a beneficial effect on archeological 

resources in the study area, particularly those located in areas identified as 

sensitive. 

Impacts on archeological resources related to fish removal are described under 

“Impacts Common to All Alternatives” in this section. 

Historic Structures. The likelihood for adverse impacts (such as vandalism) on 

historic structures would be notably reduced, resulting in a benefit in the long 

term, particularly to those areas that have been identified as sensitive. 

Cultural Landscapes. Potential impacts on cultural landscapes from the use of 

helicopters for fish management activities under alternative D are similar to those 

described earlier in the “Impacts Common to All Alternatives” section. 

More specifically, one cultural landscape exists at a lake that has been identified 

as sensitive, particularly for historic resources. This lake would revert to fishless 

under alternative D, as would be the case under alternative C. This lake and the 

associated cultural landscape currently sustain some of the highest visitor 

numbers of all 91 lakes in the study area. Elimination of anglers in this area 

would notably reduce risk of adverse impacts, a minor site-specific to localized 

benefit to cultural landscape resources around this lake. 

Ethnographic Resources. Impacts on ethnographic resources as a result of fish 

management activities under alternative D would be similar to those described in 

alternative B. 

Cumulative Impacts 

Removing fish from 62 mountain lakes in the study area would ultimately reduce 

human activity. When compared to alternative A, ground disturbance related to 

fishing and fish management activities would be eliminated over time, likely 

resulting in cumulative beneficial effects on cultural resources in the North 

Cascades Complex. 

Conclusions 

Under alternative D, the long-term effects of elimination of fishing at all of the 

mountain lakes in the study area would result in reduced human fishing activity, 

a benefit to archeological resources in the North Cascades Complex. More 

specifically, those lake and trail areas identified as sensitive regarding cultural 

resources would incur benefits by way of reduced risk of disturbance. Adverse 

impacts on cultural landscapes would likely be negligible; minor benefits may be 

realized at one designated cultural landscape where fishing would be eliminated. 

For the purpose of compliance with section 106 of the National Historic 

Preservation Act, there would be no adverse effect on cultural resources. 

Cumulative impacts would be beneficial. 
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366 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Impairment of cultural resources across the study area would not occur under 

alternative D. 

SECTION 106 SUMMARY 

This plan/EIS provides an analysis of impacts on cultural resources of four 

alternatives (the no-action alternative and three action alternatives). The project 

involves 91 lakes, 90 of which are located in designated wilderness areas. 

Visitors to the North Cascades Complex typically access areas on foot along 

existing trail networks, though cross-county hiking is required to reach some lake 

areas. Anglers (and other visitors) occasionally pack in stock (horses, mules, 

llamas), and their stays are typically one to two nights in designated camp areas. 

Overnight anglers (approximately 1,000 annually) account for approximately 

10.5% of backcountry visitors to study area lakes. Fishery management activities 

conducted by the NPS and WDFW are also typically accomplished via similar 

access routes to lake areas, though occasional helicopters or fixed-winged aircraft 

are used. 

The North Cascades Complex consists of approximately 684,000 acres, of which 

less than 5% has been inventoried for cultural resources. As a result, specific 

direct impacts on cultural resources are difficult to assess. The use of a 

Programmatic Agreement as defined under 36 CFR 800.14(b) would be 

appropriate to ensure that no adverse effects on historic properties result from the 

implementation of the proposed fishery management plan. 

Impacts are currently best assessed in areas that contain known, recorded cultural 

resources. To the extent possible, impacts have been determined by identifying 

those areas likely to be impacted (lakes and the access routes [trails] to them) and 

classifying them as to their sensitivity regarding known cultural resources 

(presence/nature). While several lakes and trails have been identified as sensitive 

based on the presence of recorded cultural resources, it is a near certainty that 

numerous and significant unidentified resources exist in the study area and are 

vulnerable to impact. The following summarizes effects on all cultural resources 

whether listed in or determined eligible for the National Register or unevaluated 

for the National Register. 

One of the greatest potential impacts on archeological resources is ground 

disturbance (from pedestrians or vehicles), a result that would occur from 

implementation of any of the alternatives. Alternative A (the no-action 

alternative) would, in the long term, result in the greatest potential for ongoing 

ground disturbance of all alternatives. While potential impact levels are 

unknown, the implementation of mitigation measures would likely ensure that 

adverse impacts would not exceed minor intensity, resulting in no adverse effect

to archeological resources. In some cases (alternatives C and D), minor benefits 

to archeological resources would be expected (no adverse effect) as a result of 

reduced human activity. 

The continuation of ongoing sport fishing under alternative A would result in 

negligible to minor adverse impacts on historic structures (no adverse effect) 
Cultural Resources 

ENVIRONMENTAL IMPACT STATEMENT 367

which would be mitigated further to negligible. The incremental reduction in 

sport fishing activities under alternatives B, C, and D would result in varying 

effects to historic structures, none of which is anticipated to exceed the minor 

intensity (no adverse effect). Alternative D would likely create a negligible to 

minor benefit to historic structures because of its complete elimination of sport 

fishing and consequent reduction in human activity, particularly in sensitive areas 

(no adverse effect). 

Ongoing sport fishing under alternative A would likely result in adverse impacts 

on cultural landscapes in the North Cascades Complex, which would be 

mitigated to no greater than minor (no adverse effect). Incremental reduction in 

sport fishing proposed under alternatives B, C, and D would result in varying 

effects, none of which would exceed minor intensity (no adverse effect). In fact, 

the reduction of fishing opportunities proposed under alternatives C and D would 

result in minor benefits (no adverse effect) at one designated cultural landscape. 

Under alternative D, the complete elimination of sport fishing would likely result 

in negligible to minor, long-term benefits (no adverse effect) to cultural 

landscapes in the North Cascades Complex. The use of helicopters for fish 

management activities under all alternatives has the potential to create minor 

visual impacts (no adverse effect) to cultural landscapes that would likely be 

mitigated further. 

While the potential to impact ethnographic resources exists under alternative A, 

no specific resources are known (no recorded resources). The potential to 

adversely affect ethnographic resources exists to an unknown degree under 

alternatives B, C, and D in that these alternatives propose chemical fish removal 

actions; however, any adverse impacts would likely be mitigated to negligible 

(no adverse effect) through negotiated agreements among the NPS, affected 

Tribes, and the State Historic Preservation Office. 

Cumulative major adverse impacts on cultural resources have occurred in the 

past as a result of the construction of hydroelectric projects (dams, reservoirs, 

related facilities) in the form of site inundation and destruction (adverse effect). 

These adverse effects were created at a time when little or no formal protection 

existed for historic properties. In fact, only a small percentage of the North 

Cascades Complex has been inventoried to date. A North Cascades Complexwide inventory of cultural resources, including shorelines of reservoirs and lakes 

associated with the hydroelectric projects where archeological resources are 

known to exist, would result in major, regional benefits to cultural resources in 

the North Cascades Complex (no adverse effect). Ongoing recreational use of the 

North Cascades Complex would likely result in no greater than minor adverse 

impacts on cultural resources (no adverse effect). The anticipated reduction of 

human activity, which would result under alternatives C and D, would likely 

create negligible to minor cumulative benefits to cultural resources in the long 

term (no adverse effect). 

Further reduction of potential adverse impacts on cultural resources would be 

accomplished by periodic and systematic monitoring of known/recorded cultural 

resources in the North Cascades Complex. Those cultural resources identified as 

at risk of adverse impacts would be evaluated for National Register eligibility (if 

they have not yet been), and where necessary, mitigation measures would be 
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368 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

implemented. These actions would include monitoring, site stabilization, and 

visitor management actions (signage, interpretive materials). The NPS would 

actively work with affected Tribes to protect ethnographic resources and privacy 

for traditional activities. 

In cases where they have not been identified as part of this analysis, potential 

adverse impacts (as defined in 36 CFR 800) on cultural resources listed in or 

eligible for listing in the National Register would be coordinated between the 

NPS and the State Historic Preservation Office to determine the level of effect on 

the property and to determine any necessary mitigative measures. 

NPS staff at the North Cascades Complex would continue to educate visitors 

regarding cultural resource protection, with particular emphasis on surface 

artifacts, architectural features, and traditional activities. If necessary, additional 

mitigation measures would be developed in consultation with the State Historic 

Preservation Officer and affected Tribes. Continuing implementation of the 

Cultural Resources Management Guidelines and adherence to NPS Management 

Policies (NPS 2001a) and the 1995 Service-wide Programmatic Agreement with 

the Advisory Council on Historic Preservation and National Conference of State 

Historic Preservation Officers would all aid in reducing the potential to adversely 

impact historic properties. 

Copies of this plan/EIS have been distributed to affected/concerned Native 

American Tribes, the Washington State Historic Preservation Officer, and the 

Advisory Council on Historic Preservation for review and comment related to 

section 106 compliance. 

Pursuant to 36 CFR Part 800.5, implementing regulations of the National 

Historic Preservation Act that address the criteria of effect and adverse effect, the 

NPS finds that implementing a fishery management plan for the North Cascades 

Complex, with mitigation measures, would not result in any new adverse 

impacts, (no adverse effect) to archeological sites, historic structures, or 

ethnographic resources currently identified as eligible for or listed in the National 

Register. In some cases, benefits to these resources would occur as a result of 

implementation of the proposed alternatives (no adverse effect). 
ENVIRONMENTAL IMPACT STATEMENT 369

VISITOR USE 

AND EXPERIENCE 

RECREATIONAL USE 

GUIDING REGULATIONS AND POLICIES 

The NPS Management Policies (NPS 2001a) state that the enjoyment of park 

resources and values by the people of the United States is part of the fundamental 

purpose of all parks and that the NPS is committed to providing appropriate, 

high-quality opportunities for visitors to enjoy the parks. While recreation is a 

key component of the NPS Management Policies, they also state that “Exotic 

species will not be allowed to displace native species if displacement can be 

prevented,” and that “All exotic plant and animal species that are not maintained 

to meet an identified park purpose will be managed - up to and including 

eradication - if (1) control is prudent and feasible, and (2) the exotic species 

interferes with . . . native species or natural habitats; or disrupts the genetic 

integrity of native species.” 

This dual nature of visitor enjoyment and resource conservation is evident in the 

NPS Organic Act of 1916 and subsequent legal interpretations of it. While the 

NPS is mandated to leave resources “unimpaired for future generations,” it also 

has been directed to conserve resources when conflicts arise between visitor 

experience and those resources (refer to the “Impairment Analysis” section under 

“General Methodology” in this chapter). Guiding documents for North Cascades 

Complex, such as the Strategic Plan (NPS 2000a), also address these issues, 

stating that the purpose of the North Cascades Complex is to 

Preserve for the benefit, use, and inspiration of present and future 

generations certain majestic mountain scenery, snowfields, glaciers, 

alpine meadows, and other unique natural features, biological processes, 

and cultural resources in the North Cascades. 

Provide outdoor recreation use and enjoyment for the public, and for the 

conservation of the scenic, scientific, historic, and other values 

contributing to public enjoyment within Ross Lake and Lake Chelan 

National Recreation Areas. 

The goals of providing recreational opportunities and protecting the natural 

systems in the North Cascades Complex are also evident in the objectives of 

this plan/EIS. With regard to recreation and conservation, the objectives state that 

this plan/EIS should 

Advance the protection and rehabilitation of native biological integrity by 

maintaining native species abundance, viability, and sustainability. 

Provide a spectrum of recreational opportunities, including sport fishing, 

while minimizing impacts to the biological integrity of natural mountain 

lakes. 
E NVIRONMENTAL C ONSEQUENCES

370 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

METHODOLOGY AND ASSUMPTIONS 

The purpose of this impact analysis is to identify the level of impact that 

implementing each of the proposed alternatives would have on recreational 

opportunities available in the North Cascades Complex. 

To determine the impacts on visitor use and experience, two major groups of 

users important in this analysis were identified: anglers who participate in or 

value fishing in the mountain lakes in the North Cascades Complex, and nonanglers who participate in other forms of recreation in the North Cascades 

Complex. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The study area for this analysis is the North Cascades Complex (see “Map 1” 

located in the envelope that accompanied this document) and the 91 naturally 

formed mountain lakes in the North Cascades Complex that currently have, or at 

one time had, a fish presence as a result of either documented or undocumented 

fish stocking activities. The 91 lakes addressed in this plan/EIS are scattered 

throughout the North Cascades Complex: 7 are in Ross Lake National Recreation 

Area, 15 are in Lake Chelan National Recreation Area, and the remaining 69 are 

located in the north and south units of North Cascades National Park (for more 

details, refer to the “Alternatives” chapter). 

I MPACT T HRESHOLD D EFINITIONS

The impact intensities for visitor use are defined below. Where impacts to visitor 

experience become moderate or minor, it is assumed that current visitor 

satisfaction would begin to decline, and the North Cascades Complex would not 

be achieving some of its long-term visitor goals. The impact thresholds below 

refer to adverse impacts unless otherwise stated in the analyses as beneficial 

effects. 

Negligible. No impacts on the visitor experience or only temporary effects are 

expected. There would be little noticeable change in visitor experience (or in the 

defined indicators of visitor satisfaction) or behavior. 

Minor. Desired visitor experience is changed, but without appreciably limiting or 

enhancing critical characteristics of the experience. Visitor satisfaction remains 

stable (that is, 20% of the users are not satisfied with their experience). Other 

areas in the North Cascades Complex would remain available for similar visitor 

experience and use without derogation of the resources and values of the North 

Cascades Complex. 

Moderate. Critical characteristics of the desired experience are changed, or the 

number of participants engaging in an activity is altered. Visitor satisfaction 

begins to decline (that is, 20% to 50% of the users are not satisfied with their 

experience). Other areas in the North Cascades Complex would remain available 

for similar visitor experience and use without derogation of the resources and 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 371

values of the North Cascades Complex, but some visitors who desire this 

experience would be required to pursue their choice in other available local or 

regional areas. 

Major. Impacts eliminate or detract from multiple critical characteristics of the 

desired experience or greatly reduce or increase participation. Visitor satisfaction 

declines substantially (that is, more than 50% of the users are not satisfied with 

their experience). Other areas in the North Cascades Complex would remain 

available for similar visitor experience and use without derogation of the 

resources and values of the North Cascades Complex. Some visitors who desire 

this experience would be required to pursue their choice in other available local 

or regional areas. Other visitors may not be able to duplicate their desired 

experience elsewhere. 

IMPACTS OF THE ALTERNATIVES 

ON VISITOR RECREATIONAL USE 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A (no action) would continue existing management practices of the 

91 lakes in the study area. The “Alternatives” chapter provides a detailed 

description of alternative A. For more information on the 91 lakes, refer to 

table 5 and figure 4 in the “Alternatives” chapter, appendix E, and “Map 2” and 

“Map 2 Table” located in the envelope that accompanied this document. 

Visitation increased throughout the North Cascades Complex between 2000 and 

2001, but had decreased during the prior two years (1999 and 2000). The impacts 

from flooding that occurred in October 2003 have largely been repaired, but the 

Upper Stehekin Valley Road remains extensively damaged and impassable to 

vehicles; its fate remains uncertain. Long-term closure of the road would reduce 

backcountry use of the Stehekin Valley, but it is otherwise assumed that 

visitation levels for the North Cascades Complex would remain steady over the 

next 10 years. 

The majority (80% in 2002) of the visitors to the North Cascades Complex 

recreate in Ross Lake National Recreational Area along State Route 20 and do 

not venture far from the highway corridor. These visitors participate in bicycling, 

day hiking, picnicking, and fishing, as well as touring the hydroelectric project in 

the summer. Because these visitors do not travel into the backcountry areas of the 

North Cascades Complex, which includes the study area’s 91 lakes, they likely 

would experience no effects from implementation of alternative A. 

Visitors enjoy other activities in the North Cascades Complex such as boating, 

paddling, hunting (in the recreation areas only), hiking, camping, 

mountaineering, horseback riding, and fishing in mountain lakes, creeks, rivers, 

and reservoirs. No boating or paddling occurs in the mountain lakes. Very few 

people hunt, which is limited to the national recreation areas, and hunting season 

typically occurs in the fall and winter, when mountain lakes ice over, and 
E NVIRONMENTAL C ONSEQUENCES

372 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Family outing

 at Cascade Pass.

Camping at Perfect Pass.

visitation is low; therefore, no impacts are expected on, or from, these users. 

Impacts on the remaining visitors to the North Cascades Complex are discussed 

below. 

Impacts on Hikers 

and Backcountry Campers 

Hikers. Day hiking is one of the most popular backcountry activities in the North 

Cascades Complex. Although most lakes in the park cannot be fished in one day, 

eight lakes do provide day-use fishing. For most day hikers, these lakes include 

Hozomeen, Willow, Ridley, Lower and Middle Thornton, Monogram, Coon, and 

Hidden. These lakes are among the top 10 most popular fishing destinations in 

the North Cascades Complex. The relative accessibility of these lakes would lead 

to increased fishing at these locations with future increases in visitation; 

however, day-use anglers represent a small number of overall day-use visitors. 

Increased fishing of popular day-use lakes would result in a long-term, adverse 

impact on day-use visitors seeking solitude, although the current fishing pressure 

on these lakes is so slight that increased fishing pressure would probably have a 

negligible impact for the foreseeable future. 

Some of the day-use lakes were stocked by aircraft in the past, but are currently 

backpack stocked. Stocking frequency varies by lake (refer to table 6 in the 

“Alternatives” chapter), although the majority of lakes are stocked only once 

every four to five years. Stocking typically occurs after lakes thaw (usually early 

July) and before fall in order for fry to acclimatize to the lakes. The summer 

months are also when visitation is highest. Day hikers would likely experience 

negligible impacts to their use and experience from implementation of alternative 

A because angling would not be expected to noticeably increase, and aircraft 

stocking of these lakes has been discontinued and replaced with backpack 

stocking. 

Backcountry Campers. The NPS maintains over 200 backcountry overnight 

campsites. The most commonly used camps occur along the shores of Ross Lake. 

These sites accommodate between 25% and 40% of all backcountry overnight 

users (excluding users in cross-country zones). Ross Lake reservoir would not be 

affected by fishery management actions, so Ross Lake campers would 

not be affected by management actions under alternative A. 

Of the remaining 200 backcountry overnight campsites that are not 

situated along Ross Lake, numerous camps are located near fishable 

lakes (see “Map 2” and “Map 2 Table” in the envelope that 

accompanied this document). Non-anglers who camp at these lakes 

may possibly share the established camps with anglers, particularly 

where lakes provide good fishing. In addition, the two McAlester Lake 

camps, the Hozomeen Lake camp, the Thornton Lake camp, and the 

Rainbow Lake camp are among the top 10 campsites visited by anglers 

(see the “Visitor Use and Experience” section in the “Affected 

Environment” chapter for details). 

Dispersed camping is permitted in cross-country zones, and visitors commonly 

camp near lakes. Non-anglers camping in cross-country zones near lakes with 

fish would come into contact with anglers. Given the generally low and dispersed 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 373

Mountaineering in the 

North Cascades 

is becoming 

more popular. 

use of cross-country zones, there would be little competition or conflict between 

anglers and non-anglers for campsites, solitude, or other desired experiences. 

These visitors would be able to select their own camping locations and would not 

be required to use or share established campsites. 

Visitors to lakes containing stocked fish (at established campsites or within 

cross-country zones) would experience negative impacts if stocking by aircraft 

occurred during their visit. Twenty-one lakes in the study area are currently 

stocked by fixed-wing aircraft. Stocking cycles vary between lakes, and lakes are 

usually stocked during the summer when visitation is highest. Given the small 

number of backcountry campers, the low probability of camping at a lake being 

stocked by aircraft, as well as the short-term and infrequent nature of aircraft 

stocking activities, non-anglers who camp in the backcountry would experience 

negligible, adverse, temporary impacts that would occur over the long term. 

Impacts on Climbers and Mountaineers 

North Cascades is a renowned destination for mountaineering, and 

bolted sport climbing and bouldering (forms of rock climbing) are 

becoming increasingly popular in the frontcountry portions of Ross 

Lake National Recreation Area. However, the frontcountry areas of 

Ross Lake are not in the study area, so rock climbers would not be 

affected under alternative A. 

Eldorado, Forbidden, and Sahale peaks are the most popular 

mountaineering destinations. There are also several relatively popular 

lakes for fishing in these areas, including Trapper, Doubtful, and 

Hidden. Given the limited amount of backcountry overnight campsites 

(such as Pelton Basin Camp and Sahale Camp) in this area, 

mountaineers and anglers may compete for the same backcountry 

campsites at these popular locations, although there is currently no 

evidence that competition for backcounty campsites is occurring at this time. 

Mountaineering occurs throughout the remainder of the North Cascades 

Complex, though numbers are low and usage is very dispersed. Other than 

competing for campsites at certain high-use areas, conflict between mountaineers 

and anglers over campsites would not be expected because these activities 

generally do not overlap. 

Some mountaineers are believed to also fish while visiting the North Cascades 

Complex, and these individuals likely view fishing as an enjoyable component of 

their mountaineering experience. Mountaineers who fish would perceive no 

impacts to their fishing experience because management actions would remain 

unchanged under alternative A. 

Mountaineers who do not engage in or value fishing would experience impacts 

similar to those described for hikers and backcountry campers regarding noise 

from fixed-wing aircraft stocking activities. Given the low probability of 

camping at or traveling near a lake being stocked by aircraft, as well as the 

infrequent and short-term nature of stocking activities, mountaineers would 

experience negligible, adverse, temporary impacts that would occur over the long 

term. 
E NVIRONMENTAL C ONSEQUENCES

374 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A young angler.

Impacts on Stock Users 

and Horseback Riders 

Many trails and backcountry camps are available for stock use (limited to horses, 

mules, and llamas); there are 29 backcountry camps in the entire North Cascades 

Complex available for stock use. Only 11 of the 91 lakes in the study area are 

accessible by horseback, and the number of stock users who fish in mountain 

lakes is not known. Horseback riding is popular on the east side of Lake Chelan 

in the Stehekin River valley. 

Stock users would experience impacts from fixed-wing aircraft stocking at the 

lakes that are accessible by horseback. Stock users comprise less than 2% of all 

visitors to the North Cascades Complex, and 7 of the 11 lakes accessible by 

horseback would be stocked by aircraft under alternative A (refer to table 23 in 

the “Affected Environment” chapter). Aircraft stocking would occur very 

infrequently, so the adverse impacts from this activity would be negligible over 

the long term as stocking activities continue. 

Impacts on Anglers 

The majority of sport fishing in the North Cascades Complex occurs in the two 

primary reservoirs: Ross Lake and Lake Chelan, including its tributary, the 

Stehekin River. Approximately 11.5% of backcountry overnight use involves 

sport fishing (11.5% pertains to fishing at all water bodies in the North Cascades 

Complex, not just the 91 lakes). The mountain lakes most frequently fished 

appear to be those that are most accessible, with a decent potential to catch fish. 

Based on surveys conducted in the 2003 field season, less than 3% of day users 

surveyed were fishing (refer to table 25 in the “Affected Environment” chapter). 

The majority of anglers spend one or more nights in the backcountry because 

most of the lakes cannot be accessed in one day (see the “Angler Use Summary” 

section under “Visitor Use and Experience” in the “Affected Environment” 

chapter). 

Under alternative A, anglers would perceive no change to their visitor experience 

in the North Cascades Complex. Although anglers may be present at lakes when 

aircraft stocking occurs, this user group is likely to view such activity as 

compatible with their backcountry experience because aircraft stocking is a 

common method for maintaining the mountain lake fishery. Impacts on anglers 

would be beneficial and long term because they would continue to fish at the 

mountain lakes that are currently available for fishing. 

Cumulative Impacts 

Alternative A would likely not change angler use inside or outside the boundaries 

of the North Cascades Complex, so displacement of anglers to lakes outside the 

NPS boundaries would not be expected. No new resorts or major upgrades to 

existing visitor facilities are currently planned. No projects are currently 

proposed or planned that would change road access to any unit of the North 

Cascades Complex, and no new major trails or trailheads are being considered, 

although a small section of the Pacific Northwest Trail in the North Cascades 

Complex is currently under construction. Given the vast number of miles 

A
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 375

available for hiking throughout the North Cascades Complex (386 miles), this 

construction would likely have no discernable effects on visitors. 

Record flooding in the fall of 2003 damaged or destroyed many trails, roads, and 

bridges. Most of the flood damage was repaired in the 2004 field season. The 

upper Stehekin Valley Road remains extensively damaged, and an environmental 

assessment is being prepared to determine whether or not to repair the damage. 

For the foreseeable future, visitor use of the upper portion of the Stehekin Valley 

Road may remain greatly reduced, and this would cause some decline in 

backcountry visitation to portions of the upper Stehekin Valley. Some visitors 

might enjoy the increased solitude and wilderness setting, while others might 

lament the reduced access to backcountry areas in the Stehekin Valley, including 

fishable lakes. Therefore, the cumulative impacts on visitor use either would be 

adverse or beneficial to backcountry users in the Stehekin Valley. 

When combined with the overall long-term, negligible, adverse impacts on nonanglers, cumulative impacts would be minor to moderate, adverse, and short 

term, depending on the fate of the Stehekin Valley Road. When combined with 

the long-term beneficial impacts on anglers, cumulative impacts would be short 

term, minor to moderate and adverse, depending on the extent of flood damage to 

trails accessing lakes within the study area. 

Conclusion 

Impacts on non-anglers under alternative A would primarily be related to noise 

and disruption from fixed-wing aircraft stocking activities. Such adverse impacts 

would be negligible and temporary but would continue over the long term as 

stocking activities continue. Anglers would experience long-term beneficial 

impacts because they would continue to enjoy fishing activities unchanged from 

the past. Cumulative impacts would result from the partial loss of the Stehekin 

Valley Road due to flooding that occurred in the fall of 2003. The fate of the road 

is currently uncertain. If the road is not repaired, then access to backcountry 

portions of the Stehekin Valley may be more difficult, and this would reduce the 

amount of backcountry visitation. Some visitors might enjoy the increased 

solitude and wilderness setting, while others might lament the reduced access to 

backcountry areas in the Stehekin Valley, including fishable lakes. Therefore, 

adverse cumulative impacts on visitor use would be minor to moderate over the 

long term. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The goal of this alternative is to eliminate or reduce reproducing fish populations 

from select lakes in the national park and the two national recreation areas. The 

“Alternatives” chapter provides a detailed description of alternative B. For more 

information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” chapter, 

appendix E, and “Map 2” and “Map 2 Table” located in the envelope that 

accompanied this document. 
E NVIRONMENTAL C ONSEQUENCES

376 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The spectacular

view is worth 

the long hike.

The majority of the North Cascades Complex’s visitors (80% in 2002) recreate in 

the frontcountry portions of Ross Lake National Recreation Area along State 

Route 20 and do not venture far from the highway corridor. Because frontcountry 

visitors do not travel into the backcountry of the North Cascades Complex, they 

would likely experience no impacts from implementation of alternative B. 

Impacts on Hikers 

and Backcountry Campers 

Hikers. Most day-use fishing currently occurs at Hozomeen, 

Willow, and Ridley, Lower and Middle Thornton, 

Monogram, Coon, and Hidden lakes. Under alternative B, the 

reproducing population of brook trout in Hozomeen Lake 

(one of the most popular fishing destinations in the North 

Cascades Complex) would be removed, if feasible, and the 

lake would remain fishless. The reproducing population of 

cutthroat trout at Monogram Lake would be removed and 

then restocked after a resting period. Management actions 

would not change for the other readily accessible day-use 

lakes, and they would remain available for fishing. The loss 

of fishing opportunity in Hozomeen lake, and the temporary 

loss of fishing opportunity at Monogram Lake, might have a 

beneficial impact on day hikers seeking greater solitude 

because fewer anglers may be present. The magnitude of this 

beneficial impact would be very slight because anglers 

represent a small number of overall day-use visitors to these lakes. For example, 

of the 244 estimated day users who visited Hozomeen, Willow, and Ridley lakes 

in 2003, only 7 were estimated to be anglers (refer to table 25). 

Under this alternative, strong preference would be given to backpack stocking 

(stocking frequency varies by lake and occurs during summer months) as 

opposed to fixed-wing aircraft. Of the lakes listed above, Hidden, Thornton 

(Lower and Upper), and Monogram might be stocked by aircraft. Aircraft 

stocking would only be used if it was determined that fish would not survive a 

long-distance backpack trip. Noise from the presence of aircraft continuing 

stocking activities would be reduced compared to alternative A since fewer lakes 

would be stocked. Aircraft stocking occurs very infrequently, so negligible, 

beneficial impacts on day hikers would continue over the long term. 

Under alternative B, up to 49 lakes either would be treated to remove fish or 

maintained as fishless. Fish removal activities would likely have a short-term, 

adverse impact on day hikers who may perceive the presence of helicopters, field 

crews, and the application of chemical (piscicide) or gillnetting/electrofishing 

treatments as incompatible with their visitor experience. The duration of fish 

removal treatments would vary according to methods. For example, gillnetting 

would likely occur over a three-year period. Chemical treatment with the 

piscicide antimycin would take place over several days in one summer season. 

Gillnetting/electrofishing would occur during the summer and fall months, which 

coincide with peak visitor use. Chemical (piscicide) treatment would vary 

according to fish species and would occur prior to spawning. The timing would 

be early season for cutthroat trout and later in the season (August or early 

September) for brook trout (see the “Alternatives” chapter for details). Spawning 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 377

habitat exclusion, recommended at this point for just one lake (Wilcox/Lillie, 

Upper) would probably have a negligible impact on day-use visitors because the 

lake is remote and seldom visited. Natural treatment methods (that is, cessation 

of stocking) would have a negligible impact on the day-use visitor experience. 

Only a handful of lakes would be treated in any given season, and most of the 

lakes would not be accessible by day users. In light of these reasons, the impacts 

of alternative B on day-use hikers would be negligible. 

Mitigation to reduce impacts on day-use visitors from management actions would 

include visitor education and public outreach to inform the public when and 

where these actions would take place (see appendix I). 

Backcountry Campers. The North Cascades Complex maintains over 200 

backcountry campsites. The most commonly used backcountry camps occur 

along the shores of Ross Lake. These sites accommodate between 25% and 40% 

of all backcountry users (excluding users in cross-country zones). Because Ross 

Lake reservoir is not part of this plan/EIS, Ross Lake campers would likely 

experience no effect from implementation of this alternative. 

Reduced angling opportunities at certain lakes under alternative B would reduce 

the number of backcountry campers at lakes that currently contain fish (refer to 

“Map 1 Table” and “Map 2 Table”). 

Dispersed camping is permitted in cross-country zones, and camping next to 

lakes in cross-country zones is common. Non-anglers camped in cross-country 

zones near lakes with fish would come into contact with anglers, although the 

number of lakes available for fishing would be reduced compared to 

alternative A. Given the generally low backcountry use at developed camps, and 

low, dispersed use of cross-country zones, there would be little competition or 

conflict between anglers and non-anglers for campsites, solitude, or other desired 

experiences. 

Visitors to lakes containing stocked fish (either at formally established campsites 

or in cross-country zones) would experience negative impacts if stocking 

activities, particularly stocking by fixed-wing aircraft, occurred during their visit. 

However, fewer lakes would be available for fishing under this alternative (29) 

than alternative under A (62), and preference would be given to backpack 

stocking. Although backpack stocking would also interfere with backcountry 

campers’ visitor experience, this type of lake stocking would likely be viewed as 

more compatible and less intrusive. Compared to alternative A, backcountry 

campers who are also non-anglers would experience beneficial long-term impacts 

since there would be fewer lakes affected by stocking activities. 

Backcountry campers would also be exposed to fish removal activities, as 

described above for hikers. Backcountry visitors may view such activity as more 

intrusive, since they may be more interested in achieving a wilderness experience 

than day users, and have invested considerably more effort to reach the 

backcountry. Several factors, however, would reduce the potential impact of fish 

removal on the visitor experience. A small number of lakes would be treated each 

season, and the lakes proposed for treatment are located in cross-country zones 

that do not receive high backcountry visitation. The lakes include Lower and 
E NVIRONMENTAL C ONSEQUENCES

378 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Hiking is a popular

activity in the North 

Cascades Complex.

Middle Blum, Triplet Lower and Upper, Diobsud No. 1 and No. 2 (including 3 

other lakes in the area), and Wilcox/Lillie (including 4 other lakes in the area). 

The cross-country zones and camps near the 91 lakes in the study area 

are shown on “Map 2” and “Map 2 Table.” In addition, rangers issuing 

backcountry overnight use permits would inform campers when fish 

removal treatments are occurring and would recommend alternate 

destinations. Therefore, impacts from fish removal efforts would be 

minor to moderate under alternative B. 

Impacts on Climbers and 

Mountaineers 

As described under alternative A, rock climbers would likely 

experience no effect under alternative B because they primarily use 

frontcountry areas around Ross Lake. As described under alternative A, 

some popular mountaineering peaks are located near lakes that are also 

popular with anglers, particularly Doubtful Lake, which experiences the 

highest amount of backcountry fishing visitation in the North Cascades 

Complex each season and would be stocked under alternative B. 

Therefore, mountaineers and anglers would share access and may 

compete for the same backcountry campsites at these locations. Some 

mountaineers, though, also fish while visiting the North Cascades Complex, and 

these individuals likely view fishing as compatible with mountaineering. Given 

the relatively small number of mountaineers that visit the North Cascades 

Complex, any adverse impacts on mountaineers related to fishing in the 

backcountry are likely to be negligible. Mountaineers who fish would perceive 

negligible impacts on their fishing experience. 

Mountaineers would experience impacts similar to those described for hikers and 

backcountry campers regarding stocking activities. The preference given to 

backpack stocking under this alternative would result in beneficial effects that 

would occur over the long term. Regarding lake treatment activities, such 

activities would occur over the course of a few seasons, and not all lakes would 

be treated at once; therefore, impacts from fish removal treatments would be 

short term, adverse, and minor. 

The overall impacts on mountaineers who do not engage in sport fishing would 

be beneficial over the long term. Short-term, negligible to minor adverse impacts 

would occur from lake treatment actions under alternative B over the long term. 

Mitigation to reduce impacts on visitors from management actions included 

public outreach to inform the public when and where these actions would take 

place (see appendix I). 

Impacts on Stock 

Users and Horseback Riders 

The high-use areas in the study area are illustrated on “Map 2” and “Map 2 

Table” (located in the envelope that accompanied this document). There are 

29 backcountry camps in the North Cascades Complex available for stock 

(horses, mules, llamas) users and horseback riders. Of the 91 lakes, 11 are 

accessible by horseback. Some of the more popular fishing lakes are in the Lake 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 379

Cutthroat trout from 

Willow Lake (top). 

Brook trout from 

Hozomeen Lake 

(bottom). 

Chelan area; these lakes are also accessible by horseback. Management actions 

for alternative B would include returning some of these lakes to a fishless 

condition, while others are treated and restocked (refer to “Map 1 Table” and 

“Map 2 Table”). Impacts of returning some lakes to a fishless condition would be 

moderate, adverse, and long term for stock users that fish in the lakes in Lake 

Chelan National Recreation Area. For those stock users and horseback riders who 

do not engage in sport fishing, impacts from treatment of lakes (mechanical and 

chemical fish removal) would be minor and adverse over the short term but 

beneficial over the long term as management actions are completed. 

Impacts on Anglers 

The majority of sport fishing in North Cascades Complex occurs at Ross Lake 

reservoir and Lake Chelan, including its tributary, the Stehekin River. 

Approximately 10.5% of backcountry overnight users fish (in the 91 study area 

lakes that currently contain fish), and only a few lakes in the North Cascades 

Complex are visited by day-use anglers; the majority of backcountry mountain 

lake fishing requires overnight use. 

Of the 91 lakes in the study area, approximately 29 would be 

available for fishing over the long term, compared with 62 under 

alternative A (refer to tables 5 and 10 in the “Alternatives” chapter). 

Fish removal would take time and may not be feasible for all lakes 

targeted for removal; these lakes would continue to be fishable until 

fish were removed (refer to table 7). Although all lakes that would 

have fish removed and undergo a resting or evaluation period before 

being restocked (pertains to 13 lakes) may still be available for 

fishing, several years (possibly from five to eight) would pass before 

the lakes would be successfully fished. 

Following fish removal or evaluation, some lakes may be restocked, 

others may not. Anglers would have to wait for stocked fry to mature 

to a catchable size, and thus, some of these lakes may not be 

immediately available for fishing, which would increase the amount 

of adverse impact anglers would experience. Since the majority of 

lakes affected are in the backcountry, overnight or backpacking 

anglers would be most affected by alternative B, compared to dayuse anglers. 

Of the most popular day-use fishing destinations, only Hozomeen 

Lake would become fishless under alternative B. Willow and Ridley 

lakes, which are located in the same area, would continue to be 

stocked. Lower and Middle Thornton, Hidden, and Coon lakes, 

which are also popular day-use fishing destinations, would continue 

to be stocked as well. Monogram Lake would be stocked after 

reproducing fish are removed. 

Lake treatment methods to remove fish would adversely affect some anglers’ 

experience. As described for other park visitors, the presence of helicopters and 

equipment, such as gillnets, would be disruptive over the short and long term 

because fish removal would be a long, slow process. Therefore, the impact on 
E NVIRONMENTAL C ONSEQUENCES

380 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Damage caused by floods is a 

chronic problem for NPS

management. This photo 

shows a December 2004 

debris flow on Rhode Creek

that blocked the entrance to 

Colonial Creek campground

in Ross Lake National

Recreation Area.

anglers from lake treatment methods would be minor to moderate and adverse 

over the short and long term. 

Fewer mountain lakes would be available for fishing under alternative B 

compared to alternative A (see table 5 in the “Alternatives” chapter). The impact 

to anglers from lost fishing opportunity compared to alternative A would be 

moderate and adverse over the long term, particularly for some anglers who 

enjoy fishing a particular lake or group of lakes. If a favorite lake were no longer 

available for stocking, some anglers may not choose to sport fish in other 

available lakes or may not return to the North Cascades Complex at all. This loss 

of fishing opportunity for these anglers would be a major, adverse, long-term 

impact. 

Cumulative Impacts 

Under alternative B, 20 lakes would be returned to a fishless condition, and 13 

other lakes would be evaluated to determine if they should be restocked. This net 

loss of fishing opportunity would displace some day-use and backcountry anglers 

to lakes outside the North Cascades Complex, including those in Ross Lake and 

Lake Chelan National Recreation Areas and surrounding areas outside NPS 

boundaries. NPS angler survey data suggest that approximately 1,000 anglers fish 

in mountain lakes annually (see the section titled “Visitor Use and Experience” in 

the “Affected Environment” chapter). For this displacement analysis, it is 

assumed that 50% of anglers (approximately 500 anglers per year) would be 

displaced from fishing in the national park and may choose to fish in other lakes 

outside the North Cascades Complex. 

There are approximately 400 lakes available for sport fishing 

within a 100-mile radius of the North Cascades Complex, and 

many of these lakes are located on adjacent U.S. Forest Service 

lands (WDFW, M. Downen, pers. comm., 2004). The additional 

use of 500 anglers spread across 400 lakes would have a 

negligible cumulative impact on those lakes, though it is unlikely 

that anglers would be evenly displaced across such a broad area. 

A more reasonable scenario would involve angler displacement 

to relatively similar terrain found on adjacent Forest Service 

wilderness areas such as the Glacier Peak Wilderness. According 

to WDFW fishery biologists (WDFW, B. Pfeifer, pers. comm., 

2004), some of the more readily accessible lakes on adjacent 

Forest Service lands are already overused by anglers. Additional 

use of these lakes by anglers displaced from the North Cascades 

Complex would have a cumulative, adverse impact on visitor use and experience 

in those areas. The magnitude of impact would depend on individual values and 

expectations and would range from negligible to minor. 

After several years of drought, the North Cascades Complex experienced 

exceptional flooding in the fall of 2003. Many trails and several roads were 

damaged or destroyed. Most of the damage was repaired during the 2004 field 

season, with the upper Stehekin Valley Road being a notable exception. An 

environmental assessment is currently underway to evaluate alternatives for the 

extensively damaged road. Although the fate of the road remains uncertain, for 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 381

the foreseeable future, visitor use of the Stehekin Valley would be lower because 

road access into the valley has been greatly reduced. Some visitors might enjoy 

the increased solitude and wilderness setting, while others might lament the 

reduced access to backcountry areas in the Stehekin Valley, including fishable 

lakes. The cumulative impacts on visitor use from flooding either would be 

minor adverse or beneficial to backcountry users in the Stehekin Valley. 

Conclusion 

Adverse impacts on non-anglers under alternative B would primarily be related 

to lake treatment methods. These adverse impacts would be negligible to minor 

over the long term. Removal of fish from some lakes would reduce visitor use 

and have some long-term beneficial impacts on non-anglers seeking greater 

solitude in the backcountry. Impacts on most anglers overall would be minor to 

moderate, adverse, and long term from management actions under alternative B 

compared to alternative A. Major adverse impacts would occur to some anglers 

who believe fishing in North Cascade Complex lakes is a truly unique experience 

that cannot be duplicated elsewhere. Cumulative impacts related to angler 

displacement to overused areas outside the North Cascades Complex would 

overall be minor to moderate, adverse, and long term. The cumulative impact of 

reduced access in the Stehekin Valley due to flood damage would be minor 

adverse or beneficial to backcountry users. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

The emphasis of this alternative is to eliminate fish from (or maintain as fishless) 

80 of the 91 lakes in the study area; 69 of the 80 lakes are in the national park 

portion of the North Cascades Complex. Sport fishing would still be allowed in 

9 lakes in Ross Lake and Lake Chelan National Recreation Areas. Reproducing 

fish populations in 2 lakes in the recreation areas would be evaluated, and after 

evaluation, the lakes may be stocked with nonreproducing trout. Sport-fishing 

opportunities in the national park would gradually decline over time as stocked 

fish populations died off, and reproducing populations of fish were gradually 

removed, although removal of reproducing populations from the national park 

might not be feasible for some lakes (refer to table 7). If removal proved 

infeasible, these lakes would continue to provide sport-fishing opportunities for 

the foreseeable future. For lakes with stocked fish, after about 5 years, most fish 

would be gone and the quality of fishing would drop sharply (WDFW, 

M. Downen, pers. comm., 2004). Sport fishing in the national recreation areas 

would still be allowed, although reproducing populations of fish would be 

removed. In some cases the lakes would be restocked with trout that are 

incapable of reproducing. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter, appendix E, and “Map 2” and “Map 2 Table” located in the envelope 

that accompanied this document. 
E NVIRONMENTAL C ONSEQUENCES

382 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Impacts on Hikers 

and Backcountry Campers 

Day Hikers. Day-use angling currently occurs at Hozomeen, Willow, Ridley, 

Lower and Middle Thornton, Monogram, Coon, and Hidden lakes. Under this 

alternative, Hidden, Hozomeen, Monogram, and Lower and Middle Thornton 

lakes would become fishless. Willow, Ridley, and Coon (which are all popular 

fishing destinations) would continue to be stocked. Anglers represent a small 

number of overall day-use visitors, so a decrease in the amount of fishable 

mountain lakes would have a slight beneficial effect to day hikers because fewer 

people may be hiking the trails. 

Willow, Ridley, and Coon lakes would continue to be stocked. Up to 56 lakes 

would be treated to remove fish: 25 chemically, 10 mechanically, and 21 by 

natural treatment (fish would be eliminated by cessation of stocking, 

experiencing a natural die-off). Removal of fish would be a lengthy process, and 

only a handful of lakes would be treated in any given year. Day hikers would be 

negatively affected by fish removal activities (including transporting fish 

removal equipment with helicopters, use of motorized equipment, presence of 

work crews around lakes, and gillnetting) because they may perceive these 

activities as incompatible with their visitor experience. The impacts of fish 

removal on day hikers would be longer in duration than under alternative B 

because more lakes would be slated for fish removal. As in alternative B, only a 

handful of lakes would be treated in a season, so only a small portion of lakes in 

the North Cascades Complex would be affected each year. In addition, most of 

the lakes would not be accessible by day users, so fishery management actions 

would only affect a small portion of the North Cascades Complex. In contrast to 

alternative B, several more day-use lakes would undergo fish removal, leaving a 

greater number of day users impacted over the long term. In light of all these 

reasons, the impacts of fish removal on day-use hikers would be negligible to 

minor. 

To mitigate the impacts of fish removal actions of the visitor experience, the NPS 

would provide information about fish removal schedules and locations, and 

educational programs would be provided as described under alternative B. 

Backcountry Campers. Camping next to lakes (with and without fish) is 

common throughout the backcountry. The campsites located next to lakes are 

shown on “Map 2 Table,” and the management actions for alternative C are 

shown on “Map 1 Table.” 

The majority of non-anglers visiting lakes that would contain fish under 

alternative C may share the camps with anglers but only in the national recreation 

areas. The reduction of available backcountry lakes for fishing would either 

concentrate anglers in sites at those remaining lakes that provide fishing, thus 

increasing visitation and competition for limited camping sites (the impacts of 

angler displacement are discussed in the “Cumulative Impacts” section below). 

With such limited angling pressure in the backcountry, the impact of increased 

competition for campsites near national recreation area lakes with fish would 

probably be negligible. Dispersed camping is permitted in cross-country zones, 

and camping next to lakes (both with and without fish) is common. Visitors in 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 383

these areas would be able to select their own camping locations and would not be 

required to use or share established campsites. 

Fewer lakes would be available for fishing under this alternative. Visitors to 

lakes containing stocked fish (either at campsites or in cross-country zones) 

would experience negative impacts if stocking activities, particularly stocking by 

fixed-wing aircraft, occurred during their visit; preference would be given to 

backpack stocking. Although backpack stocking would also interfere with 

backcountry campers’ visitor experience, this type of lake stocking would likely 

be viewed as more compatible and less intrusive. In addition, only lakes in the 

national recreation areas would be stocked; therefore, compared to alternative A, 

backcountry campers would experience temporary, negligible, beneficial impacts 

over the long term. 

Backcountry campers would also be exposed to fish removal activities. 

Backcountry visitors may view such activities as more intrusive, since they may 

be more interested in achieving a wilderness experience than day users and may 

have invested considerably more effort to reach the high mountain camps. 

Rangers issuing backcountry overnight use permits would inform campers when 

fish removal treatments were occurring and would recommend alternate 

destinations. 

Overall impacts on hikers and backpackers under alternative C would be 

beneficial related to stocking activities but minor to moderate and adverse related 

to lake treatments to remove fish. 

Impacts on Climbers and Mountaineers 

As described under alternative A, rock climbers would likely experience no 

effect under alternative C because they primarily use frontcountry areas 

around Ross Lake. 

Mountaineers who travel the backcountry may encounter anglers on trails or 

at camps. As described under alternative A, Eldorado, Forbidden, and Sahale 

peaks are popular mountaineering destinations. The lakes near these popular 

destinations would be returned to fishless conditions, thereby reducing the 

potential competition between mountaineers and anglers for limited camping 

sites. 

The number of lakes stocked under alternative C compared to A would be 

reduced; therefore, the impact of stocking activities to visitors engaged in 

mountaineering would be negligible to minor over the long term. Lake 

treatment methods to remove fish would result in a minor to moderate 

adverse impact to visitors engaged in mountaineering since most of the lakes 

are located outside the areas where visitors climb. There would be a 

negligible beneficial impact on climbers in that the number of people using 

the study area may be reduced if numbers of anglers are reduced. 

Overall impacts on mountaineers under alternative C would be beneficial related 

to stocking activities but adverse related to fish removal treatments. These 

A base camp at 

Pioneer Ridge. 
E NVIRONMENTAL C ONSEQUENCES

384 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

adverse impacts, however, would be short term and largely avoidable if climbers 

chose to access other areas with lakes not undergoing treatment. 

Impacts on Stock 

Users and Horseback Riders 

“Map 2” (located in the envelope that accompanied this document) illustrates 

where the high-use areas are within the study area. There are 29 backcountry 

camps in the North Cascades Complex available for stock (horses, mules, llamas) 

users and horseback riders. Of the 91 lakes, 11 are accessible by horseback. 

Some of the more popular fishing lakes are in the Lake Chelan National 

Recreation Area and also accessible by horseback. Management actions for 

alternative C include returning some of these lakes to a fishless condition, while 

others are treated and restocked (refer to tables 5 and 12 in the “Alternatives” 

chapter). 

Impacts from fish stocking activities and application of lake treatments would be 

similar to those described under alternative B, particularly because most 

horseback riding occurs in the Lake Chelan National Recreation Area, which 

would continue to experience stocking activities. As under alternative B, only 

Coon Lake would continue to be stocked by aircraft. 

For those stock users and horseback riders who also engage in sport fishing in the 

Lake Chelan Recreational Area, impacts of returning some lakes to a fishless 

condition would be moderate, adverse, and long term. For those stock users and 

horseback riders who do not engage in sport fishing, impacts from treatment of 

lakes (mechanical and chemical fish removal) would be minor and adverse over 

the short term, but beneficial over the long term as management actions are 

completed. 

Impacts on Anglers 

The majority of sport fishing at the North Cascades Complex occurs at Ross 

Lake and Lake Chelan, including its tributary, the Stehekin River. Approximately 

10.5% of backcountry overnight use near the 91 study area lakes involves sport 

fishing, and only a few lakes in the North Cascades Complex are visited by dayuse anglers (the majority of high mountain lake fishing requires overnight use). 

Of the 91 lakes in the study area, approximately 9 would be available for fishing 

over the long term, compared with 62 under alternative A. Although the lakes 

that would have fish removed and undergo a resting or evaluation period before 

being restocked may still be available for fishing, several years (possibly five to 

eight) would pass before the lakes would be successfully fished. 

After fish removal or evaluation occurs, some lakes may be restocked, others 

may not. Anglers would have to wait for fry added to restocked lakes to mature 

to a catchable level. Therefore, some of these lakes may not be immediately 

available for fishing, increasing the amount of adverse impact anglers would 

experience in the form of lost fishing opportunity. Since the majority of lakes 

affected are in the backcountry, overnight or backpacking anglers would be most 

affected by alternative C compared to day-use anglers. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 385

Lake treatment methods to remove fish would adversely affect some anglers’ 

experience. As described for other park visitors, the presence of equipment, such 

as helicopters, motorboats, and gillnetting/electrofishing, would be disruptive 

over the short and long term. Fish removal would be a long, slow process, and 

many lakes would remain fishable for some time; therefore, the impact to anglers 

from lake treatment methods would be minor to moderate and adverse over the 

short and long term. 

Fewer mountain lakes would be available for fishing under alternative C 

compared to alternatives A and B (refer to tables 5, 10, and 12 and figure 4 in the 

“Alternatives” chapter). Day-use anglers would experience long-term adverse 

impacts. Under this alternative, Hidden, Hozomeen, Monogram, and Lower and 

Middle Thornton lakes, which are popular with day-use anglers, would become 

fishless, but Willow, Ridley, and Coon lakes would continue to be stocked. 

The impact to anglers from lost fishing opportunity compared to alternative A 

would be moderate and adverse over the long term. Some anglers enjoy fishing a 

particular lake or group of lakes and believe that fishing in the North Cascades 

National Park provides a unique fishing experience that cannot be duplicated 

elsewhere. For these anglers, loss of fishing opportunity in the national park 

would be a major, adverse, long-term impact. 

Anglers might benefit from decreased noise and disturbance associated with 

aircraft stocking activities that would occur under this alternative, although it is 

likely that they view such activity as compatible with their visitor experience. As 

described for other users, anglers would also experience adverse impacts as a 

result of intensive treatments to remove fish. 

Backcountry fishing opportunities would still be available in Ross Lake and Lake 

Chelan National Recreation Areas, but these opportunities would not suffice for 

some anglers who believe that fishing in the national park provides an experience 

that cannot be duplicated elsewhere. Anglers would also experience short-term, 

negligible, adverse impacts from fish removal treatments. Overall impacts would 

be moderate to major on some backcountry anglers but minor to negligible for 

others. 

Cumulative Impacts 

One cumulative impact issue for recreational use under alternative C would 

involve displacement of anglers to other areas due to lost fishing opportunity in 

the national park. Under alternative C, approximately 80 of the 91 lakes in the 

study area would be fishless over time (69 of those lakes are in the national park 

portion of the North Cascades Complex). In 9 lakes in Ross Lake and Lake 

Chelan National Recreation Areas, sport fishing would still be allowed. 

Reproducing populations of fish in 2 lakes in the recreation areas would be 

evaluated, and after evaluation, the lakes may be stocked with nonreproducing 

trout. This net loss of fishing opportunity would displace some day-use and 

backcountry anglers to lakes outside the North Cascades Complex, including the 

lakes in the two national recreation areas and surrounding area. NPS angler 

survey data suggest that approximately 1,000 anglers fish in mountain lakes 

annually (see the section titled “Visitor Use and Experience” in the “Affected 

Environment” chapter). For this displacement analysis, it is assumed that 50% of 
E NVIRONMENTAL C ONSEQUENCES

386 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

anglers (approximately 500 anglers per year) would be displaced from fishing in 

the national park and may choose to fish in other lakes outside the North 

Cascades Complex. 

There are approximately 400 lakes available for sport fishing within a 100-mile 

radius of North Cascades Complex boundaries, and many of these lakes are 

located on adjacent U.S. Forest Service lands. The additional use of 500 anglers 

spread across 400 lakes would have a negligible cumulative impact on those 

lakes, although it is unlikely that anglers would be evenly displaced across such a 

broad area. A more reasonable scenario would involve angler displacement to 

relatively similar terrain found on more adjacent Forest Service wilderness areas 

such as the Glacier Peak Wilderness. According to WDFW fishery biologists, 

some of the more readily accessible lakes on adjacent Forest Service lands are 

already overused by anglers (WDFW, B. Pfeifer, pers. comm., 2004). Additional 

use of these lakes by anglers displaced from the national park would have a 

cumulative, adverse impact on visitor use and experience. The magnitude of 

impact would depend on individual values and expectations and would range 

from negligible to minor. 

Record flooding in October 2003 damaged or destroyed many trails and several 

roads. Most of the damage was repaired during the 2004 field season, with the 

upper Stehekin Valley Road being a notable exception. An environmental 

assessment is currently underway to evaluate alternatives for the extensively 

damaged road. Although the fate of the road remains uncertain, for the 

foreseeable future, visitor use of the Stehekin Valley may be lower because road 

access into the valley has been greatly reduced. Some visitors might enjoy the 

increased solitude and wilderness setting, while others might lament the reduced 

access to backcountry areas in the Stehekin Valley, including fishable lakes. 

Therefore, the cumulative impacts on visitor use from flooding would be minor 

adverse or beneficial to backcountry users in the Stehekin Valley. 

Conclusion 

Adverse impacts on non-anglers under alternative C would be primarily related 

to lake treatment methods. These impacts would be negligible to minor and 

adverse over the long term. Removal of fish from some lakes would reduce 

visitor use and have some long-term beneficial impacts on non-anglers seeking 

greater solitude in the backcountry. Impacts on most anglers overall would be 

minor to moderate, adverse, and long term from management actions under 

alternative C compared to alternative A. Major adverse impacts would occur to 

some anglers who believe fishing in North Cascade Complex lakes is a truly 

unique experience that cannot be duplicated elsewhere. Cumulative impacts 

related to angler displacement to overused areas outside the North Cascades 

Complex would overall be minor to moderate, adverse, and long term. The 

cumulative impact of reduced access in the Stehekin Valley due to flood damage 

would be minor adverse or beneficial to backcountry users. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 387

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

The emphasis of this alternative would be to remove fish from 62 of the 91 lakes 

in the study area, with the other 29 lakes remaining fishless. Sport-fishing 

opportunities in most of these lakes would generally be eliminated within a 

period of 5 years. Self-sustaining (reproducing) populations of fish would be 

gradually removed over time. The rate of removal would depend on 

unpredictable changes in resource (funding and personnel) availability and 

differences among fish removal methods. Complete removal of self-sustaining 

populations of fish in some of the larger, deeper lakes might not be feasible (a 

feasibility analysis is provided in the “Alternatives” chapter). These lakes would 

continue to provide sport-fishing opportunities for the foreseeable future, and the 

goal of complete removal might never be achieved. For lakes with stocked fish, 

after about 5 years, most fish would be gone and the quality of fishing would 

sharply drop (WDFW, M. Downen, pers. comm., 2004). 

The “Alternatives” chapter provides a detailed description of alternative D. For 

more information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” 

chapter, appendix E, and “Map 2” and “Map 2 Table” located in the envelope 

that accompanied this document. 

Impacts on Hikers 

and Backcountry Campers 

Day Hikers. Elimination of mountain lake fishing opportunities in the North 

Cascades Complex would have a slight beneficial effect to day hikers seeking 

solitude because fewer anglers would be hiking the trails. This benefit would be 

offset through time, however, given projected increases in visitation from 

population growth in the surrounding area. In addition, anglers represent a small 

number of overall day-use visitors in the backcountry. Fish stocking activities 

would cease entirely, resulting in a long-term, beneficial impact on day hikers. 

Under alternative D, 62 of the 91 study area lakes that currently contain fish 

would be treated to remove fish. Fish removal activities would have a short-term, 

adverse impact on day hikers, as described under alternatives B and C. 

Information about fish removal schedules and locations and educational 

programs would be provided as described under alternative B. Removal of fish 

from lakes using mechanical and chemical methods would take many years, so 

day hikers would have ample opportunities to visit areas unaffected by fish 

removal actions; therefore, the short-term adverse impacts of fish removal 

activities would likely be minor to possibly moderate. 

Backcountry Campers. Backcountry visitors would be adversely impacted by 

fish removal activities such as gillnetting/electrofishing and chemical (piscicide) 

application. Backcountry visitors may view such activities as more intrusive 

since they might be more interested in achieving a wilderness experience than 

day users and would have invested considerably more effort to reach the high 

mountain camps. To mitigate this impact (see appendix I), rangers issuing 

backcountry overnight use permits would inform campers when and where fish 

removal treatments were occurring and would recommend alternate destinations. 
E NVIRONMENTAL C ONSEQUENCES

388 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Backcountry campers at all mountain lakes in the North Cascades Complex 

would experience long-term beneficial impacts from cessation of stocking. 

Under alternative D, overall impacts on backcountry users who do not fish would 

be beneficial related to cessation of stocking activities but adverse related to 

mechanical and chemical fish removal treatments. Some beneficial impacts to 

these visitors would occur because the number of anglers would decline over 

time. 

Impacts on Climbers and Mountaineers 

Eldorado, Forbidden, and Sahale peaks are the most popular mountaineering 

destinations. All lakes in the vicinity of these peaks would eventually be returned 

to fishless conditions, thereby reducing the amount of interaction between 

mountaineers and anglers. Mountaineers who fish while accessing these peaks 

would no longer be able to do so, but this adverse impact would be negligible 

because fishing is a secondary activity to mountaineering. 

Mountaineers would experience long-term, negligible, beneficial impacts from 

cessation of fish stocking activities throughout the North Cascades Complex; 

however, mountaineers would be exposed to fish removal activities that may 

impede their backcountry experience. Rangers issuing backcountry overnight use 

permits would advise visitors of fish removal activities occurring at their 

destinations and would recommend alternate destinations. Impacts from fish 

removal would be short term, minor, and adverse to possibly moderate because 

fish removal would take many years. 

Overall impacts on mountaineers under alternative D would be beneficial related 

to cessation of stocking activities, but mechanical and chemical lake treatment 

methods to return lakes to fishless conditions would result in minor to moderate 

long-term impacts. Any adverse impacts would be short term and avoidable. 

Impacts on Stock 

Users and Horseback Riders 

Some of the more popular fishing lakes are in the Lake Chelan National 

Recreation Area and accessible by horseback. Management actions for 

alternative D would include returning these lakes to a fishless condition. For 

those stock (horses, mules, llamas) users and horseback riders who also engage in 

sport fishing in the Lake Chelan National Recreational Area, impacts of returning 

lakes to a fishless condition would be long term, moderate, and adverse. For 

those stock users and horseback riders who do not engage in sport fishing, 

impacts from mechanical and chemical lake treatment activities to remove fish 

would be minor and adverse over the short term. 

Impacts on Anglers 

The majority of sport fishing in the North Cascades Complex occurs at Ross 

Lake and Lake Chelan, including its tributary, the Stehekin River. 

Implementation of this alternative is not likely to affect these visitors unless a 

substantial number of displaced mountain lake anglers choose to fish at Ross and 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 389

Stop for just a while—

quiet and still, and 

nowhere else to be. 

Chelan lakes. Sport-fishing opportunities in most of the lakes that 

currently contain fish would generally be eliminated within a 

period of 5 years. Self-sustaining (reproducing) populations of 

fish would be gradually removed over time. The rate of removal 

would depend on unpredictable changes in resource (funding and 

personnel) availability and differences among fish removal 

methods. Complete removal of self-sustaining populations of fish 

in some of the larger, deeper lakes might not be feasible (a 

feasibility analysis is provided in the “Alternatives” chapter). 

These lakes would continue to provide sport-fishing opportunities 

for the foreseeable future, and the goal of complete removal might 

never be achieved. 

Anglers would be affected by both long-term and shorter-term direct impacts of 

fish removal on the visitor experience and the permanent loss of fishing 

opportunity. Impacts on anglers’ visitor experience from fish removal activities 

would be greater than impacts on other user groups because anglers may be less 

supportive of alternative D since it would take away their ability to fish in study 

area lakes. 

The impacts on anglers from the eventual permanent loss of fishing opportunity 

in the 91 study area lakes would vary. Some casual anglers would continue to 

fish the backcountry lakes until the lakes became fishless. The eventual inability 

to fish the mountain lakes would not necessarily preclude a visit to the park for 

these anglers because they would still participate in other backcountry activities, 

such as hiking and camping, which do not involve fishing but are already part of 

the backcountry fishing experience. 

For other anglers, fishing is the primary purpose of their visit, and in some cases, 

it is an activity that has been passed down for several generations. These anglers 

believe that fishing in the North Cascades Complex is a unique experience that 

cannot be duplicated elsewhere. 

Overall impacts on anglers who fish in the mountain lakes in the study area 

would be long term, adverse, and major. It is possible that over 50% may not be 

satisfied with their experience, and participation in the desired activity would be 

greatly reduced. 

Cumulative Impacts 

The eventual loss of fishing opportunity under alternative D would displace some 

day-use and backcountry anglers to lakes outside the North Cascades Complex, 

including those in the national recreation areas and surrounding areas. NPS 

angler survey data suggest that approximately 1,000 anglers fish in mountain 

lakes annually (see the section titled “Visitor Use and Experience” in the 

“Affected Environment” chapter). For this displacement analysis, it is assumed 

that 50% of anglers (approximately 500 anglers per year) would be displaced 

from fishing in the study area lakes and may choose to fish in other mountain 

lakes outside of the North Cascades Complex. 
E NVIRONMENTAL C ONSEQUENCES

390 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

There are approximately 400 lakes available for sport fishing within a 100-mile 

radius of the North Cascades Complex, and many of these lakes are located on 

adjacent U.S. Forest Service lands. The additional use of 500 anglers spread 

across 400 lakes would have a negligible cumulative impact on those lakes, 

although it is unlikely that anglers would be evenly displaced across such a broad 

area. A more realistic displacement scenario would involve angler displacement 

to relatively similar terrain found on adjacent Forest Service wilderness areas 

such as the Glacier Peak Wilderness. According to WDFW fishery biologists, 

some of the more readily accessible lakes on adjacent Forest Service lands are 

already overused by anglers (WDFW, B. Pfeifer, pers. comm., 2004). Additional 

use of these lakes by anglers displaced from the North Cascades Complex would 

have a cumulative adverse impact on visitor use and experience. The magnitude 

of impact would depend upon individual values and expectations and would 

range from negligible to minor. 

Record flooding in October 2003 damaged or destroyed many trails and several 

roads in the North Cascades Complex. Most of the damage was repaired during 

the 2004 field season, with the upper Stehekin Valley Road being a notable 

exception. An environmental assessment is currently underway to evaluate 

alternatives for the extensively damaged road. Although the fate of the road 

remains uncertain for the foreseeable future, visitor use of the Stehekin Valley 

would be lower because road access into the valley has been greatly reduced. 

Reduced access to the upper Stehekin Valley, coupled with the permanent loss of 

fishing opportunity in that same area, would have a cumulative impact on the 

visitor experience that is difficult to gage at this time because the future of the 

road remains uncertain. 

Conclusion 

Adverse impacts on non-anglers under alternative D would be primarily related 

to the lake treatment methods. These impacts would be negligible to minor and 

adverse over the long term. Removal of fish from some lakes would reduce 

visitor use and have some long-term beneficial impacts on non-anglers seeking 

greater solitude in the backcountry. Impacts on most anglers overall would be 

minor to moderate, adverse, and long term from management actions under 

alternative D compared to alternative A. Major adverse impacts would occur to 

some anglers who believe fishing in North Cascade Complex lakes is a truly 

unique experience that cannot be duplicated elsewhere. Cumulative impacts 

related to angler displacement to overused areas outside the North Cascades 

Complex would overall be minor to moderate, adverse, and long term. The 

cumulative impact of reduced access in the Stehekin Valley due to flood damage 

would be minor adverse or beneficial to backcountry users. 

Overall, cumulative impacts would be moderate, adverse, and long term. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 391

Organized volunteers 

began stocking lakes 

in the 1930s. 

SOCIAL VALUES 

GUIDING REGULATIONS AND POLICIES 

The National Environmental Policy Act requires that economic and social effects 

be analyzed when they are interrelated with actions that also have natural or 

physical effects. Economic effects are addressed in the “Socioeconomic 

Resources” section of this chapter. The section, “Impacts of the Alternatives on 

Social Values,” analyzes effects on those who may or may not visit the North 

Cascades Complex but have expressed various points of view representing their 

“values” regarding the management actions proposed by the alternatives in this 

plan/EIS. 

METHODOLOGY AND ASSUMPTIONS 

Similar to the methodology used for assessing impacts on visitor use and 

experience, the impacts on social values are assessed given the degree to 

which management actions would change compared to existing 

management of the 91 lakes in the study area. The “Social Values” 

section in the “Affected Environment” chapter describes the definitions 

of various attitudes expressed toward wildlife management (refer to 

“Table 26: People’s Perceptions of Animals in American Society”). 

This analysis is anecdotal and qualitative and based upon comments 

received during public scoping and the history of the fish stocking issue 

as documented in Louter (2003). Impacts on social values are 

characterized according to the simplifying assumption that “angler and 

angler groups” would value management actions that maintain the 

mountain lakes fishery, and “conservationists or conservation groups” 

would value management actions that would protect native ecosystems 

by reducing or eliminating the mountain lakes fishery. The limits of this 

simplifying assumption are clearly evident because social values 

encompass a wide spectrum of possibilities that defy discrete 

characterization—many anglers are conservationists, and many 

conservationists are anglers. Recognizing these limitations, the specific purpose 

of this analysis is to evaluate the impacts on social values regarding the 

maintenance of an artificial, nonnative recreational fishery in an NPS unit for the 

purpose of enhancing recreation. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The study area for this analysis is the North Cascades Complex (see “Map 1” 

located in the envelope that accompanied this document) and the 91 naturally 

formed mountain lakes in the North Cascades Complex that currently have, or at 

one time had, a fish presence as a result of either documented or undocumented 

fish stocking activities. The 91 lakes addressed in this plan/EIS are scattered 

throughout the North Cascades Complex: 7 are in Ross Lake National Recreation 

Area, 15 are in Lake Chelan National Recreation Area, and 69 are located in the 
E NVIRONMENTAL C ONSEQUENCES

392 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

north and south units of North Cascades National Park (for more details, refer to 

the “Alternatives” chapter). 

I MPACT T HRESHOLD D EFINITIONS

Negligible. Impacts on views or values would not be perceptible or measurable. 

Minor. Impacts on views or values would be detectable but only localized or to a 

small number of groups or individuals holding these values. 

Moderate. Impacts on views or values would be detectable throughout the region 

(within the three counties surrounding the North Cascades Complex) or to one or 

more groups or numbers of individuals holding these values. 

Major. Impacts on views or values would be detectable in and outside the region 

to larger numbers of individuals or groups holding these values. 

IMPACTS OF THE 

ALTERNATIVES ON SOCIAL VALUES 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A would continue existing management of 91 lakes in the study area. 

The “Alternatives” chapter provides a detailed description of alternative A. For 

more information on the 91 lakes, refer to table 5 and figure 4 in the 

“Alternatives” chapter, appendix E, and “Map 1” (located in the envelope that 

accompanied this document). 

Impacts on Social Values 

of Anglers and Angler User Groups 

Mountain lake fishing in the North Cascades Complex follows a tradition that 

precedes its designation as a unit of the NPS by almost a century. Many anglers 

and angler user groups hold values similar to those holding conservation values. 

In fact, groups such as the Trail Blazers, Inc. and Washington State Hi-Lakers 

have assisted agencies in scientific studies and monitoring and are committed to 

protection of a healthy fishery. 

Alternatives A provides for continued stocking of lakes in accordance with 

current practices. The NPS has determined that continued stocking under 

alternative A would require congressional action to clarify the enabling 

legislation to provide the NPS the authority to stock lakes in wilderness (for more 

information on this issue, please refer to the section titled “Implementing the 

Fishery Management Plan Through Congressional Action” in the “Alternatives” 

chapter). If Congress were to provide this authority, then the values of anglers 

and angler user groups would most likely not be affected because their activities 

would not be altered. If Congress does not act, then management actions would 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 393

default to alternative D. The impacts on social values of anglers and angler user 

groups are defined under alternative D in this section. 

Impacts on Social Values of 

Conservationists and Conservation Groups 

In contrast to the value placed on the mountain lakes fishery by anglers who 

prefer the challenge and extreme scenic values found in the North Cascades 

Complex, many other groups and individuals believe that the mountain lakes 

fishery in the North Cascades Complex violates the spirit and intent of the 

Wilderness Act and the NPS conservation mission. While many anglers are also 

conservationists, there is a distinction between those who value the stocking of 

lakes for their enjoyment and those who oppose maintenance of a nonnative 

fishery because they place greater value on the conservation and protection of 

natural processes. Many of the conservation values are intertwined with 

wilderness values. Because the Wilderness Act speaks directly to specific 

wilderness values, that topic is addressed separately. 

There has been a long-standing debate regarding the stocking of the mountain 

lakes and potential effects on resources in the North Cascades Complex (see the 

“Purpose of and Need for Action” chapter). The debate as to whether continued 

stocking violates NPS Management Policies (NPS 2001a), and whether Congress 

would or should sanction fish stocking, would have a continued impact to 

conservationists and conservation groups who oppose continued stocking and 

have expressed their views in and outside the region. Actions to return lakes to a 

fishless condition in the Sierra Nevada in California, for example, have been 

broadly supported by agencies, such as the U.S. Fish and Wildlife Service, and 

by conservation groups. 

Congressional action to clarify the North Cascades Complex enabling legislation 

to allow for continued fish stocking would set a precedent for this NPS unit, and 

possibly others that have, or may have in the future, fish stocking issues. Should 

Congress act to clarify the North Cascades Complex enabling legislation to allow 

existing management practices to continue, a moderate to major adverse impact 

to the social values of conservationists and conservation groups would occur over 

the long term. 

Cumulative Impacts 

Continuation of management actions as described in alternative A would not alter 

angler use; therefore, impacts on social values of anglers would be long term and 

beneficial. 

Continuation of management actions as described in alternative A would have a 

moderate to major adverse long-term cumulative impact to conservationists and 

conservation groups because of the perception that fish stocking and presence of 

fish in naturally fish-free waters is in conflict with the purposes of a national park 

unit. Some may feel that this would set a precedent for other agencies. Although 

it is unknown to what extent other agencies would continue, stop, or reduce their 

stocking activities in the future, the perception of such potential would influence 

conservationists’ perceptions on a broad scale. 
E NVIRONMENTAL C ONSEQUENCES

394 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Two Trail Blazers 

packing in with 

stocking gear.

Conclusion 

Continuation of existing management actions under alternative A would 

have a beneficial effect on the social values of anglers and angler groups 

because stocking and sport fishing would not change. Impacts on social 

values of conservationists and conservation groups would be long term, 

moderate to major, and adverse. 

Continuation of management actions as described in alternative A would 

not alter angler use; therefore, cumulative impacts on social values of 

anglers would be long term and beneficial. Continuation of management 

actions as described in alternative A would have a moderate to major 

adverse cumulative impact on conservationists and conservation groups. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative would be to eliminate or reduce reproducing fish 

populations from select lakes in the study area. Restocking of nonreproducing 

fish would be allowed only where biological resources would be protected. Based 

on best available science, some lakes would be restocked with nonreproducing 

fish at low densities once reproducing fish have been removed. If critical 

information needed to make management decisions is missing for some lakes, 

those lakes would not be stocked until that information becomes available. An 

extensive monitoring program (see appendix F) would be implemented to enable 

adaptive management and avoid major adverse impacts of fish on native biota. 

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Impacts on Social Values 

of Anglers and Angler Groups 

While alternative B would reduce angling opportunities in some lakes, the 

alternative also attempts to protect and enhance the mountain lakes fishery over 

the long term. Some anglers and groups who would be affected by the reduction 

of fishing opportunities either in the short term (while lakes are treated and 

potentially restocked) or over the long term (returning other lakes to a fishless 

condition), may oppose this alternative. Compared to alternative A, impacts on 

the social values of anglers and angler groups would be long term, minor, and 

adverse. However, some anglers and angler groups would also view adaptive 

management as beneficial. The impacts on social values of anglers and angler 

groups if Congress does not act to clarify the enabling legislation are described 

below under alternative D. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 395

Impacts on Social Values of 

Conservationists and Conservation Groups 

The intent of alternative B would be to enable adaptive management and 

minimize impacts on biological integrity (see the section titled “Adaptive 

Management” in the “Alternatives” chapter). While some conservationists and 

conservation groups may view this as a beneficial effect of this alternative, others 

may still oppose any efforts to continue stocking over the long term, even if lakes 

were restocked with nonreproducing fish and other measures were taken to 

minimize impacts on biological integrity. Therefore, the impact would be 

beneficial for some but moderate to major and adverse over the long term for 

others. 

Cumulative Impacts 

Management actions described in alternative B would alter angler use; therefore, 

social values of anglers would be affected. The use of the study area by anglers 

and the cumulative effects on angler use are described under “Impacts of 

Alternatives on Visitor Recreational Use” in this section. When added to the 

effects of this alternative, minor to moderate cumulative effects are expected, 

mostly related to the flooding damage to the upper Stehekin Valley Road that 

occurred in October 2003. 

Alternative B would have a moderate to major adverse cumulative impact to 

conservationists and conservation groups, and some may support an adaptive 

management approach as defined for alternative B because of the perception that 

fish stocking and presence of fish in naturally fish-free waters is in conflict with 

the purposes of a national park unit, including national recreation areas. Some 

may feel this would set a precedent for other agencies. Although it is unknown to 

what extent other agencies would continue, stop, or reduce its stocking activities 

in the future, the perception of such potential would influence conservationists’ 

perceptions on a broad scale. Cumulative impacts on anglers and angler groups 

would be moderate to major, adverse, and long term compared to alternative A, 

although some may support the adaptive management approach, which may 

reduce impacts. 

Conclusion 

Alternative B would have a minor adverse impact on the social values of anglers 

and angler groups over the long term because some level of stocking and sport 

fishing would continue over the long term. Impacts on social values of 

conservationists and conservation groups would be beneficial for some who 

would support the new management framework, but moderate to major adverse 

and long term for those who oppose any stocking of lakes over the long term. 

Alternative B would have a moderate to major adverse cumulative impact on 

conservationists and conservation groups, but some may support the adaptive 

management approach, which may reduce impacts to some degree. Cumulative 

impacts on anglers and angling groups would be moderate to major, adverse, and 

long term, but some may support the adaptive management approach, which may 

reduce impacts to some degree. Cumulative impacts related to flood damage to 
E NVIRONMENTAL C ONSEQUENCES

396 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

the upper Stehekin Valley Road would be minor to moderate, adverse, and long 

term. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

The emphasis of this alternative would be to eliminate fish from (or maintain as 

fishless) 80 of the 91 lakes in the study area; 69 of the 80 lakes are in the national 

park portion of the North Cascades Complex; sport fishing would still be allowed 

in 9 lakes in Ross Lake and Lake Chelan National Recreation Areas. 

Reproducing fish populations in 2 lakes in the recreation areas would be 

removed, and after evaluation, the lakes may be stocked with nonreproducing 

trout. Sport-fishing opportunities in the national park would gradually decline 

over time as stocked fish populations died off and reproducing populations of 

fish were gradually removed, although removal of reproducing populations from 

the national park might not be feasible for some lakes (refer to table 7). If 

removal proved infeasible, these lakes would continue to provide sport-fishing 

opportunities for the foreseeable future. For lakes with stocked fish, after about 

5 years most fish would be gone, and the quality of fishing would drop sharply 

(WDFW, M. Downen, pers. comm., 2004). In order to protect native biological 

resources, alternative C would focus on reducing or eliminating reproducing fish 

in the lakes located in the national recreation areas. Sport fishing in the national 

recreation areas would still be allowed, although reproducing populations of fish 

would be removed, and in some cases, the lakes would be restocked with trout 

that are incapable of reproducing. Management actions to remove reproducing 

fish populations would proceed at a rate governed by the availability of funding 

and personnel. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Impacts on Social Values 

of Anglers and Angler Groups 

The number of lakes available for angler use in alternative C, compared to 

alternative A, would be greatly reduced, with fishing in the national park portion 

of the North Cascades Complex eventually eliminated over time. Angling 

opportunities would be limited to select lakes in the national recreation areas (see 

the “Impacts of Alternatives on Visitor Use and Experience” section of this 

chapter). While sport fishing would continue to some degree in the national 

recreation areas, anglers who value fishing in the high mountain lakes in the 

national park portion of North Cascades Complex would experience a moderate 

to major adverse impact over the long term. The impact on social values of 

anglers and groups should Congress not enact a change to the enabling legislation 

is described under alternative D. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 397

Impacts on Social Values of 

Conservationists and Conservation Groups 

While the number of lakes available for stocking world be reduced in 

alternative C compared to alternative A, some conservationists and conservation 

groups may still view stocking as inappropriate; others might view this as a 

legitimate compromise. This is because NPS Management Policies regarding fish 

stocking contain several exceptions, one of which pertains to lakes that have 

previously been stocked in recreation areas (NPS 2001a, 4.4.3). The impact on 

conservationists and conservation groups would be beneficial for some but 

moderate to major adverse and long term for others. 

Cumulative Impacts 

Management actions described in alternative C would alter angler use; therefore, 

social values of anglers and angler groups would be affected. The use of study 

area lakes by anglers and the cumulative effects on angler use is described under 

“Impacts of the Alternatives on Visitor Recreational Use” in this section. When 

added to the effects of this alternative, minor to moderate cumulative effects are 

expected and mostly related to the flooding damage to the upper Stehekin Valley 

Road that occurred in October 2003. 

Alternative C would have a moderate to major adverse long-term cumulative 

impact on conservationists and conservation groups because of the perception 

that fish stocking and presence of fish in naturally fish-free waters is in conflict 

with the purposes of a national park unit, including national recreation areas. 

Some may feel that this would set a precedent for other agencies. Although the 

extent to which other agencies would continue, stop, or reduce its stocking 

activities in the future is unknown, the perception of such potential would 

influence conservationists’ perceptions on a broad scale. 

Conclusion 

Alternative C would have a moderate to major adverse impact on the social 

values of anglers and angler groups over the long term because sport fishing 

would eventually be eliminated in the national park, and many anglers and angler 

groups believe that fishing in the park is a unique opportunity that cannot be 

duplicated elsewhere. Impacts on social values of conservationists and 

conservation groups would be beneficial for some who would support the new 

management framework but moderate to major adverse and long term for those 

who oppose any stocking of lakes over the long term. 

Alternative C would have a moderate to major adverse cumulative impact on 

conservationists and conservation groups, but some may support the adaptive 

management approach, which may reduce impacts to some degree. Cumulative 

impacts on anglers and angling groups would be moderate to major, adverse, and 

long term, but some may support the adaptive management approach, which may 

reduce impacts to some degree. Cumulative impacts related to flood damage to 

the upper Stehekin Valley Road would be minor to moderate, adverse, and long 

term. 
E NVIRONMENTAL C ONSEQUENCES

398 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Under alternative D, the goal would be to remove fish from 62 of the 91 lakes in 

the study area, with 29 lakes remaining fishless. Sport-fishing opportunities in 

most of these lakes would generally be eliminated within a period of 5 years. 

Self-sustaining (reproducing) populations of fish would gradually be removed 

over time. The rate of removal would depend on unpredictable changes in 

resource (funding and personnel) availability and differences among fish removal 

methods. Complete removal of self-sustaining fish populations in the 9 larger, 

deeper lakes identified in table 7 might not be feasible. These lakes would 

continue to provide sport-fishing opportunities for the foreseeable future, and the 

goal of complete removal might never be achieved. Congressional action would 

not be required to implement this alternative. 

The “Alternatives” chapter provides a detailed description of alternative D. For 

more information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” 

chapter and appendix E. 

Impacts on Social Values 

of Anglers and Angler Groups 

Elimination of sport fishing in the 91 lakes would have a moderate to major 

adverse impact on social values of anglers and angler groups. 

Impacts on Social Values of 

Conservationists and Conservation Groups 

Overall, the impact on social values of conservationists and conservation groups 

would be beneficial. 

Cumulative Impacts 

Management actions described in alternative D would substantially alter angler 

use; therefore, social values of anglers and angler groups would be affected. The 

use of the study area by anglers and the cumulative effects on angler use is 

described under “Impacts of the Alternatives on Visitor Recreational Use” in this 

section. When added to the effects of this alternative, moderate to major adverse, 

long-term cumulative effects are expected. 

Alternative D would have a beneficial cumulative impact on conservationists and 

conservation groups over the long term. 

Conclusion 

Alternative D would have a moderate to major adverse impact on the social 

values of anglers and angler groups over the long term, especially for those who 

use and value the park for this experience. Anglers may choose to pursue sport 

fishing outside the North Cascades Complex. Overall, impacts on social values of 

conservationists and conservation groups would be beneficial. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 399

Alternative D would have a moderate to major adverse cumulative impact on 

conservationists and conservation groups, but some may support the adaptive 

management approach, which may reduce impacts to some degree. Cumulative 

impacts on anglers and angling groups would be moderate to major, adverse, and 

long term, but some may support the adaptive management approach, which may 

reduce impacts to some degree. Cumulative impacts related to flood damage to 

the upper Stehekin Valley Road would be minor to moderate, adverse, and long 

term. 

WILDERNESS VALUES 

GUIDING REGULATIONS AND POLICIES 

The Washington Park Wilderness Act of 1988 (WPWA) established 93% of the 

North Cascades Complex as the Stephen T. Mather Wilderness and directed the 

NPS to manage the wilderness in accordance with the Wilderness Act of 1964. 

The Wilderness Act, passed on September 3, 1964, “provides a degree of 

protection to the resources of the National Park System that the National Park 

Service Organic Act does not” (NPS 1999c). The House Report accompanying 

the Act, which helps to clarify Congressional intent with respect to the Act, states 

that its purpose is to establish a National Wilderness Preservation System made 

up of designated wilderness areas, “because of the undeveloped character of their 

lands and the need to protect and manage them in order to preserve, as far as 

possible, the natural conditions that now prevail” (House Report No. 1538, at 7, 

88th Congress, 2nd session [July 2, 1964]). The section titled “Wilderness Values” 

in the “Affected Environment” chapter further describes the Wilderness Act, the 

legislation that created the wilderness areas in the North Cascades Complex, and 

the wilderness characteristics and values specific to the Stephen T. Mather 

Wilderness in the North Cascades Complex. 

METHODOLOGY AND ASSUMPTIONS 

The analyses of impacts on wilderness values is qualitative and based upon 

comments received during public scoping, the history of the issue as documented 

in Louter (2003), and review of literature regarding wilderness values of the 

American public. 

The magnitude and intensity of impacts on wilderness values greatly depends 

upon individual perspectives. Those engaged in wilderness management have 

found it useful to characterize impacts on wilderness values according to two 

alternative philosophical perspectives on wilderness: anthropocentric and 

biocentric. The anthropocentric perspective emphasizes human use and 

enjoyment of wilderness. The biocentric perspective emphasizes protection and 

maintenance of natural processes and conditions (Hendee and Stankey 1973). 

According to Hendee and Dawson (2002), the alternative labels—

anthropocentric and biocentric—can “create a false distinction between 

wilderness ‘for people’s sake’ and wilderness ‘for nature’s sake.’” This analysis 

is not intended to perpetuate these distinctions, nor is it intended to argue that 

either perspective is right or wrong. Use of the anthropocentric and biocentric

concepts is merely a convenient way of describing how fishery management 

actions would impact wilderness values according to different perspectives. 

Anthropocentric: 

This perspective 

emphasizes human 

use and enjoyment of

wilderness. 

Biocentric: This 

perspective 

emphasizes 

protection and 

maintenance of 

natural processes 

and conditions. 
E NVIRONMENTAL C ONSEQUENCES

400 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

“You must teach your children that the ground beneath their feet is the ashes of our

grandfathers. So that they will respect the land, tell your children that the earth is rich with

the lives of our kin . . . all things are connected.” 

attributed to Chief Seattle
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 401

This impact section focuses on the enduring wilderness values implicit in the 

Wilderness Act that visitors can experience when visiting the Stephen T. Mather 

Wilderness; those values are 

opportunities for solitude 

opportunities for primitive, unconfined forms of recreation (for example, 

the freedom for visitors to pursue nonmotorized recreational activities 

such as hiking, climbing, and sport fishing) 

naturalness, or the prevalence of natural conditions with little evidence of 

human impact or manipulation of natural conditions 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The study area for this analysis includes the Stephen T. Mather Wilderness, 

which makes up 93% of the North Cascades Complex (see “Map 1” located in 

the envelope that accompanied this document). For more details, refer to the 

“Alternatives” chapter. 

Members of the public who may potentially be affected include wilderness users 

who would experience firsthand the potential impacts on wilderness values 

during their wilderness visit. There are other members of the public, however, 

that might never visit the Stephen T. Mather Wilderness and would never 

experience impacts on wilderness values firsthand, but they would still be 

impacted simply by knowing that various fishery management actions were 

occurring. 

I MPACT T HRESHOLD D EFINITIONS

Negligible. Fishery management actions would have no discernable impact on 

opportunities for solitude. Opportunities for primitive and unconfined forms of 

recreation would essentially remain unchanged. Natural conditions would prevail 

with little evidence of human manipulation. The wilderness area would be 

affected primarily by the forces of nature. There would be outstanding 

opportunities for solitude or a primitive and unconfined type of recreation. 

Minor. Fishery management actions would have a slightly beneficial or adverse 

impact on opportunities for solitude in limited areas of the wilderness. 

Opportunities for primitive and unconfined forms of recreation would be slightly 

improved or reduced in limited areas of the wilderness. Natural conditions would 

predominate, though human-caused impacts (either beneficial or adverse) on the 

natural environment would be slightly detectable in limited areas of the 

wilderness. 

Moderate. Fishery management actions would have a readily apparent, 

beneficial or adverse impact on opportunities for solitude in limited areas of the 

wilderness. Opportunities for primitive and unconfined forms of recreation would 

be noticeably improved or reduced in limited areas of the wilderness. Natural 
E NVIRONMENTAL C ONSEQUENCES

402 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

conditions would predominate, though human-caused impacts (either beneficial 

or adverse) on the natural environment would be readily apparent in limited areas 

of the wilderness. 

Major. Fishery management actions would have a readily apparent beneficial or 

adverse impact on opportunities for solitude throughout the wilderness area. 

Opportunities for primitive and unconfined forms of recreation would be 

substantially improved or reduced throughout the wilderness area. Human-caused 

impacts (either beneficial or adverse) on the natural environment would be 

readily apparent throughout the wilderness. 

Impairment. Impairment would occur when the wilderness resources have been 

substantially altered, eliminating the characteristics that meet the criteria for 

consideration and classification as wilderness. Criteria for determining 

classification as wilderness can be found in NPS Management Policy 6.2.1, 

Assessment of Wilderness Suitability or Nonsuitability (NPS 2001a). 

IMPACTS OF THE 

ALTERNATIVES ON WILDERNESS VALUES 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

The current mountain lakes fishery management activities at the North Cascades 

Complex would continue under the no-action alternative. The “Alternatives” 

chapter provides a detailed description of alternative A. For more information on 

the 91 lakes, refer to table 5 and figure 4 in the “Alternatives” chapter and 

appendix E. 

The mountain lakes fishery management actions under alternative A that would 

directly affect wilderness values include stocking and related activities and very 

limited monitoring. The mountain lakes fishery would indirectly affect visitor use 

of lakes by providing fishing opportunities. Maintenance of the mountain lakes 

fishery would continue to affect the naturalness of the wilderness by 

manipulating natural processes to maintain an artificial recreational fishing 

opportunity. 

Impacts on Opportunities for Solitude 

Under alternative A, stocking of select lakes in the park and national recreation 

areas would continue in accordance with established practices. Most lakes would 

continue to be backpack stocked, which would occur very infrequently at a given 

lake, and the stocking activity would generally be limited to a few individuals. 

Therefore, backpack stocking would have a negligible direct short- and long-term 

impact on visitor solitude. Fixed-wing aircraft would be used as a method to 

stock lakes that could not be backpack stocked. Aircraft stocking would 

markedly disrupt visitor solitude along the flight path of the aircraft and 

especially above the lakes being stocked. The duration of impact, however, 

would be very brief (about a minute over a given lake every few years for each 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 403

lake stocked) and very infrequent. Given the short-term and infrequent nature of 

aircraft stocking, there would be a minor adverse short- and long-term impact on 

opportunities for solitude. 

Sport-fishing opportunities in the park and national recreation areas would 

remain at current levels. Continued stocking would provide opportunities for 

sport fishing and indirectly impact the solitude of other backcountry visitors such 

as hikers, climbers, or stock (horses, mules, llamas) users. 

It is estimated that about 1,000 anglers currently fish the mountain lakes each 

year. Table 22 in the “Affected Environment” chapter shows that the average 

annual visitation to the North Cascades Complex from 1996 to 2002 was about 

412,012 people. Table 24 shows that fishing in all North Cascades Complex 

waters (streams, rivers, reservoirs, ponds, mountain lakes) accounts for 11.5% of 

total visitor use. Backcountry use permit data for 2003 show that 4,035 visitors 

were issued backcountry overnight use permits, and that roughly 10.5% (424) of 

visitors who were issued permits were planning on fishing at study area lakes 

(62 of these lakes currently have fish). A 2003 survey of day-use visitors shows 

that approximately 75 day users were engaged in fishing at the most accessible 

day-use lakes in the study area. The estimate of 1,000 anglers who currently fish 

the study area lakes each year is derived from the backcountry permit data and 

the 2003 survey data (the estimate takes into account incomplete sampling due to 

dispersed access, highly variable and broad times of entry and departure, and 

purposeful or inadvertent avoidance of backcountry permit registrations). 

These statistics indicate that angler use is a relatively small portion of overall 

wilderness use, and it is spread across a very wide area. Many of the lakes that 

contain stocked or self-sustaining populations of fish are located in untrailed or 

cross-country portions of the wilderness that receive very little use (refer to 

“Map 2” and “Map 2 Table”). Opportunities for solitude would remain negligibly 

impacted in these areas of the wilderness that receive very little use over the long 

term. Some fishable lakes, however, are located in relatively high-use areas. 

Continuing to provide sport-fishing opportunities (through stocking or benign 

neglect of reproducing fish populations) at these lakes would continue angling 

and reduce opportunities for solitude. In these areas, continuing to provide sportfishing opportunities would have a minor, adverse impact on opportunities for 

solitude over the long term. 

Impacts on Opportunities 

for Primitive Recreation 

Fishing opportunities throughout the wilderness would remain at current levels. 

Continued angler use of these areas would affect recreational use by non-anglers. 

Most of the lakes in the North Cascades Complex are located in untrailed 

portions of the wilderness that receive very low use by hikers, climbers, and 

other non-anglers. Some fishable lakes, however, are located in areas with 

relatively high use. Continuing to provide sport-fishing opportunities at these 

lakes may displace other recreational activities during summer high-use periods 

by limiting the number of permits available for other users. Impacts to other 

visitors’ opportunities for primitive recreation in high-use areas over the summer 

would be minor to moderate adverse over the long term. It is noted that some 
E NVIRONMENTAL C ONSEQUENCES

404 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

illegal stocking has occurred in the past and may continue to occur under 

alternative A. It is impossible to quantify the degree to which illegal stocking has 

occurred or may occur. 

Impact on Naturalness 

Continuing the current management of the mountain lakes fishery would allow 

self-sustaining and stocked populations of fish to persist. These actions would 

perpetuate the existence of a nonnative, artificial fishery in lakes that were 

naturally fish free and would therefore diminish the value of naturalness in the 

Stephen T. Mather Wilderness. The magnitude of the impact would depend upon 

individual perception and experience. 

Some wilderness users would not be aware that fish were even present in the 

lakes. Some visitors might notice the fish but not realize they were nonnative and 

may react indifferently. The impacts on the wilderness value of naturalness for 

these visitors would be negligible over the long term with regard to fishery 

management because they would encounter what they perceive to be “pristine” 

natural conditions in most of the wilderness. Those with anthropocentric 

perspective (valuing human use and enjoyment of wilderness) would experience 

negligible long-term impacts under alternative A. 

On the other hand, some informed wilderness users would be aware of nonnative 

fish in the lakes due to stocking. They would also experience the indirect effects 

of angling, such as social trails along lakeshores, fire rings, and lost or discarded 

fishing tackle and equipment. The magnitude of adverse impact would vary 

among individuals. Those with strong biocentric views (support protection of 

natural processes in wilderness areas) of wilderness would experience major, 

long-term adverse impacts from the continued fishery management practices 

under alternative A. 

Some people would not even have to experience these impacts firsthand to be 

adversely affected. Without ever visiting the North Cascades Complex, these 

individuals would be adversely impacted simply by knowing that the naturalness 

of the North Cascades Complex was being impacted by the current mountain 

lakes fishery management practices. The magnitude of impact is unknown. 

Cumulative Impacts 

The flooding in October 2003 destroyed most of the upper portion of the 

Stehekin Valley Road. For the foreseeable future, access to various portions of 

the Stehekin Valley may take much longer and may exclude some visitors from 

accessing portions of the area. Most mountain lake anglers are used to hiking 

long distances, often off trail, to access lakes, so the cumulative impact on 

mountain lake fishing opportunities from reduced access would likely be 

negligible over the short and long terms. 

Stocked and reproducing populations of fish would remain in wilderness lakes 

throughout the region, including the study area lakes in the Stephen T. Mather 

Wilderness in the North Cascades Complex. This would be a major, long-term 

adverse cumulative impact on those who believe that continued stocking, as 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 405

proposed under alternative A, in wilderness and benign neglect of reproducing 

populations of fish would compromise natural processes. This would be a longterm negligible cumulative impact on those who believe that human use and 

enjoyment of wilderness should continue. 

Conclusion 

Backpack stocking would have a direct short- and long-term negligible impact on 

visitor solitude. Given the short-term and infrequent nature of fixed-wing aircraft 

stocking, there would be a short- and long-term minor adverse impact on 

opportunities for solitude. Sport-fishing opportunities would remain at current 

levels. This would result in long-term negligible adverse impacts on 

opportunities for solitude for those areas that receive relatively little use, and 

long-term, minor adverse impacts on opportunities for solitude for those areas 

that receive high use. 

Impacts on other visitors’ opportunities for primitive recreation in high-use areas 

over the summer would be minor to moderate adverse over the long term. 

Those with anthropocentric perspective (valuing human use and enjoyment of 

wilderness) would experience long-term negligible impacts under alternative A. 

Those with strong biocentric views (support protection of natural processes in 

wilderness areas) of wilderness would experience long-term major adverse 

impacts by the continued fishery management practices under alternative A. 

Impacts on wilderness users who are not aware that fish are present in the lakes 

would be negligible over the long term. 

Cumulative impacts on fishing opportunities in mountain lakes from reduced 

access would likely be negligible over the short and long terms. 

There would be a major, long-term adverse cumulative impact on those who 

believe that continued stocking and continued presence of reproducing fish 

populations under alternative A would compromise natural processes in 

wilderness. There would be long-term negligible cumulative impacts on those 

who believe that human use and enjoyment of wilderness should continue. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative would be to eliminate self-sustaining 

(reproducing) populations of fish from select lakes in the study area. Restocking 

of nonreproducing fish would be allowed in select lakes provided biological 

integrity would be conserved. Stocking of low densities of fish incapable of 

reproducing would be allowed to continue in select lakes. Stocking would be 

discontinued in lakes where data are currently lacking to make informed 

management decisions. A monitoring program (see appendix F) would be 

implemented in order to enable adaptive management of lakes. 
E NVIRONMENTAL C ONSEQUENCES

406 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Impacts on Opportunities for Solitude 

Compared to alternative A, fewer lakes in the national park and national 

recreation areas would be stocked. Most lakes would continue to be backpack 

stocked, which would occur very infrequently at a given lake, and the stocking 

activity would generally be limited to a few individuals; therefore, stocking 

would continue to have a negligible direct impact on visitor solitude over the 

long term. Fixed-wing aircraft would be used as a method to stock lakes that 

would not be backpack stocked, although fewer lakes would be stocked via 

aircraft compared to alternative A. Aircraft stocking would markedly disrupt 

visitor solitude along the flight path of the aircraft and especially above the lakes 

being stocked. The duration of impact, however, would be very brief (about a 

minute over a given lake) and very infrequent (once every few years). Given the 

short-term and infrequent nature of fixed-wing aircraft stocking, there would be a 

minor adverse short- and long-term impact on opportunities for solitude under 

alternative B. 

Management actions related to fish removal include the use of chemical 

treatments (piscicides) and mechanical treatments, which would require the use 

of helicopters, motorized boats, electrofishing gear, gillnetting, and the routine 

presence of crews at select lakes. Gillnetting and piscicide application would 

require use of a helicopter to ferry heavy gear and the use of electrofishing gear 

to supplement netting. Piscicide use would be limited to one lake at time and 

probably only one or two lakes would be treated per season. Gillnetting would 

occur at several lakes at one time, depending on the availability of personnel and 

equipment. The noise and visual disturbance from these management actions 

would affect the solitude at lakes undergoing treatment and in areas along the 

flight path of helicopters or the access routes. Helicopter use would be limited to 

a few flights in a few locations over the course of a season. To minimize impacts 

on visitor solitude, NPS staff issuing backcountry overnight use permits would 

encourage users to visit areas not undergoing fish removal actions. Taken 

together, the impacts on solitude from fish removal activities would be long term 

minor to moderate adverse because most of the wilderness would remain 

unaffected by fish removal actions. 

Fishery management actions would reduce sport-fishing opportunities in the 

national park and national recreation areas compared to alternative A. 

Opportunities for solitude would be even greater in these areas because there 

would be fewer anglers present to disrupt the solitude of other wilderness users. 

This would be a long-term minor beneficial impact. Some lakes in certain highuse areas would remain fishable. Continuing to provide sport-fishing 

opportunities (through stocking or where removal of self-sustaining fish 

populations may not be feasible) at these lakes would encourage angling and 

impact other users’ opportunities for solitude. In these areas, continuing to 

provide sport-fishing opportunities would have a minor adverse impact on 

opportunities for solitude over the long term. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 407

Impacts on 

Opportunities for Primitive Recreation 

Over time, many lakes with self-sustaining populations or stocked populations of 

fish would become fishless, and the overall opportunity for fishing in the 

wilderness would be reduced compared to alternative A. Loss of fishing 

opportunity would have an adverse impact on mountain lake anglers. Some 

anglers may simply fish elsewhere. Impacts on these anglers would be minor and 

long term. Other anglers believe that the lakes in North Cascades Complex offer 

a unique fishing opportunity that cannot be duplicated elsewhere; these anglers 

would experience major adverse impacts over the long term from lost fishing 

opportunities. 

Continued angler use of lakes that remain fishable may limit the available 

backcountry overnight permits for other wilderness users. Most of the lakes in 

the North Cascades Complex are located in untrailed portions of the wilderness 

that receive very low use by hikers, climbers, and other non-anglers (refer to 

“Map 2” and “Map 2 Table”). Some fishable lakes, however, are located in areas 

that experience relatively high use. Compared with alternative A, angler use 

would become more concentrated at certain lakes that remain fishable. 

Continuing to provide sport-fishing opportunities (through stocking or where 

removal of self-sustaining populations may not be feasible) at these lakes would 

displace other recreational activities during summer high-use periods by limiting 

the number of permits available for other users. Impacts on other visitors’ 

opportunities for primitive recreation in high-use areas over the summer would 

be minor to moderate adverse over the long term. It is noted that some illegal 

stocking has occurred in the past and may continue to occur under alternative B. 

It is impossible to quantify the degree to which illegal stocking has or may occur. 

Impacts on Naturalness 

Management of the mountain lakes fishery under alternative B would allow 

stocked populations of fish to persist. These actions would perpetuate the 

existence of a nonnative, artificial fishery in mountain lakes that were naturally 

fish free and would therefore diminish the value of naturalness in the Stephen T. 

Mather Wilderness. The magnitude of the impact would depend upon individual 

perception and experience. 

Some wilderness users would not be aware that fish were even present in the 

lakes. Some visitors might notice the fish but not realize they were nonnative and 

may react indifferently. The impacts on the wilderness value of naturalness for 

these visitors would be negligible over the long term with regard to fishery 

management because they would encounter what they perceive to be “pristine” 

natural conditions in most of the wilderness. Those with anthropocentric 

perspective (valuing human use and enjoyment of wilderness) would experience 

negligible long-term impacts under alternative B. Some individuals with an 

anthropocentric perspective would view the application of a science-based 

adaptive management plan as a negligible impact, and some would view this as 

beneficial. 

On the other hand, some informed wilderness users would be aware of nonnative 

fish in the lakes due to stocking. They would also experience the indirect effects 
E NVIRONMENTAL C ONSEQUENCES

408 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

of angling, such as social trails along lakeshores, fire rings, and lost or discarded 

fishing tackle and equipment. The magnitude of adverse impact would vary 

among individuals. Those with strong biocentric views (support protection of 

natural processes in wilderness areas) of wilderness would experience major, 

long-term adverse impacts from the fishery management actions proposed under 

alternative B. Some with a biocentric perspective would view the application of a 

science-based adaptive management plan as beneficial. 

Some people would not even have to experience these impacts firsthand to be 

adversely affected. Without ever visiting the North Cascades Complex, these 

individuals would be adversely impacted by simply knowing that the naturalness 

of the North Cascades Complex was being impacted by mountain lakes fishery 

management actions proposed under alternative B. The magnitude of impact is 

unknown. 

Cumulative Impacts 

The flooding in October 2003 destroyed most of the upper portion of the 

Stehekin Valley Road. For the foreseeable future, access to various portions of 

the Stehekin Valley may take much longer and may exclude some visitors from 

accessing portions of the area. Most mountain lake anglers are used to hiking 

long distances, often off trail, to access lakes, so the cumulative impact on fishing 

opportunities in mountain lakes from reduced access would likely be negligible 

over the short and long term. 

Stocked and some reproducing populations of fish would remain in wilderness 

lakes throughout the region, including the study area lakes in the Stephen T. 

Mather Wilderness in the North Cascades Complex. This would be a major, longterm adverse cumulative impact on those who believe that continued stocking (as 

proposed under alternative B) in wilderness and continued presence of 

reproducing populations of fish would compromise natural processes. There 

would be a long-term negligible cumulative impact on those who believe that 

human use and enjoyment of wilderness should continue. Depending on one’s 

views regarding the application of science-based adaptive management principles 

in wilderness areas, cumulative impacts either would be beneficial or adverse 

over the long term. Fishery management actions, especially fish removal, would 

impose an administrative presence in wilderness, in addition to established 

administrative actions such as research and monitoring, ranger patrols, and fire 

management actions. Taken together, these additional fishery management 

actions would have a minor, adverse cumulative impact on solitude over the long 

term. 

Conclusion 

Backpack stocking would have a negligible direct impact on visitor solitude over 

the long term. Given the short-term and infrequent nature of fixed-wing aircraft 

stocking, there would be a short- and long-term minor adverse impact on 

opportunities for solitude. Fishery management actions would reduce sportfishing opportunities in the national park and national recreation areas compared 

to alternative A. This would result in a long-term minor beneficial impact on 

opportunities for solitude in some areas. However, select lakes in certain high-
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 409

use areas would remain fishable, resulting in minor adverse impacts on 

opportunities for solitude over the long term. The impacts on solitude from fish 

removal activities would be minor to moderate and adverse over the long term. 

Anglers who choose to fish elsewhere due to reduced fishing opportunities would 

experience long-term minor adverse impacts. Anglers who believe the fishing 

experience cannot be duplicated elsewhere would experience long-term major 

adverse impacts. Impacts on other visitors’ opportunities for primitive recreation 

in high-use areas over the summer would be minor to moderate adverse over the 

long term. 

Those with anthropocentric perspective (valuing human use and enjoyment of 

wilderness) would experience long-term negligible impacts under alternative B. 

Some of those with an anthropocentric perspective would view the application of 

a science-based adaptive management plan as a negligible impact, and some 

would view this as beneficial. Those with strong biocentric views (support 

protection of natural processes in wilderness areas) of wilderness would 

experience long-term major adverse impacts from fishery management actions 

under alternative B. Some with biocentric perspectives would view the 

application of a science-based adaptive management plan as beneficial over the 

long term. Impacts on wilderness users who are not aware that fish are present in 

the lakes would be long term and negligible. 

Cumulative impacts on fishing opportunities in mountain lakes from reduced 

access would likely be negligible over the short and long terms. 

There would be a long-term major adverse cumulative impact on those who 

believe that the continued stocking (as proposed under alternative B) in 

wilderness and continued presence of reproducing populations of fish would 

compromise natural processes in wilderness. There would be long-term 

negligible cumulative impacts on those who believe that human use and 

enjoyment of wilderness should continue. Depending on one’s views regarding 

the application of science-based adaptive management principles in wilderness 

areas, cumulative impacts would be long-term beneficial or adverse. Fishery 

management actions, including fish removal, would have long-term minor 

adverse cumulative impacts on solitude. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

The emphasis of this alternative would be to discontinue stocking fish in the 

national park portion of the North Cascades Complex and remove all selfsustaining (reproducing) populations of fish, where feasible. Stocking of 

nonreproducing fish in select lakes in the national recreation areas would be 

allowed provided biological integrity would be conserved. Some lakes in the 

national recreation areas would continue to be stocked, though stocking would be 

discontinued in lakes where data are currently lacking to make informed 

management decisions. A monitoring program (see appendix F) would be 
E NVIRONMENTAL C ONSEQUENCES

410 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

implemented in order to enable adaptive management of lakes in the national 

recreation areas. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Impacts on Opportunities for Solitude 

No lakes in the national park portion of the North Cascades Complex would be 

stocked. Select lakes in the national recreation areas would continue to be 

backpack stocked, which would continue to have a long-term negligible direct 

impact on visitor solitude. Fixed-wing aircraft would be used as a method to 

stock lakes that would not be backpack stocked, although fewer lakes would be 

stocked via aircraft compared to alternatives A and B. Aircraft stocking would 

markedly disrupt visitor solitude along the flight path of the aircraft and 

especially above the lakes being stocked. The duration of impact, however, 

would be very brief (about a minute over a given lake) and very infrequent (every 

few years for each lake stocked). Given the short-term and infrequent nature of 

aircraft stocking, there would be a short- and long-term minor adverse impact on 

opportunities for solitude. 

The management actions related to fish removal would be similar to 

alternative B; however, more lakes would be subjected to fish-removal activities 

under alternative C. The impacts on solitude from fish removal actions would be 

short-term minor to moderate adverse because most of the wilderness would 

remain unaffected by fish removal actions at any one time. 

Sport-fishing opportunities in national park lakes would eventually be eliminated, 

except in larger, deeper lakes where complete fish removal might not be feasible 

(refer to table 7). Sport fishing would continue in select national recreation area 

lakes. Compared with alternatives A and B, opportunities for solitude would be 

even greater in the North Cascades Complex, over time, because fewer lakes 

would be available for fishing. This would have a moderate beneficial impact on 

solitude in these areas over the long term. Some lakes in certain high-use areas in 

the national recreation areas would remain fishable, and continuing to provide 

sport-fishing opportunities would have a minor adverse impact on opportunities 

for solitude over the long term. 

Impact on 

Opportunities for Primitive Recreation 

Loss of fishing opportunity in the national park would have an adverse impact on 

mountain lake anglers. Some anglers may simply fish elsewhere. Impacts on 

these anglers would be minor and long term. Other anglers believe that the lakes 

in North Cascades Complex offer a unique fishing opportunity that cannot be 

duplicated elsewhere; these anglers would experience long-term, major adverse 

impacts from lost fishing opportunities. 

Continued angler use of lakes that remain fishable under alternative C may limit 

the available backcountry overnight permits for other wilderness users. Some 

fishable lakes in the national recreation areas are located in areas receiving 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 411

relatively high use. Angler use would become more concentrated at certain lakes 

that remain fishable. Continuing to provide sport-fishing opportunities (through 

stocking or where removal of self-sustaining populations may not be feasible) at 

these lakes may displace other recreational activities during summer high-use 

periods by limiting the number of permits available for other users. Impacts on 

other visitors’ opportunities for primitive recreation in high-use areas over the 

summer would be minor to moderate adverse over the long term. It is noted that 

some illegal stocking has occurred in the past and may continue to occur under 

alternative C, although it is impossible to quantify the degree to which illegal 

stocking has occurred or may occur in the future. Sport fishing is very important 

to many wilderness enthusiasts. Some mountain lake anglers believe that current 

mountain lake fishing opportunities are limited compared to the past. These 

anglers believe, to varying degrees, that many other lakes in the North Cascades 

Complex should be fishable. Compared with alternatives A and B, fishing 

opportunities would be further reduced, and this would have a major, adverse 

impact on these anglers. 

Impacts on Naturalness 

Management of the mountain lakes fishery under alternative C would allow 

stocked populations of fish to persist in select lakes in the national recreation 

areas and in nine lakes in the national park where complete fish removal may not 

be feasible (refer to table 7 in the “Alternatives” chapter). These actions would 

perpetuate the existence of a nonnative, artificial fishery in mountain lakes that 

were naturally fish free and would therefore diminish the value of naturalness in 

the Stephen T. Mather Wilderness. The magnitude of impact would depend upon 

individual perception and experience. 

Similar to alternatives A and B, some wilderness users would not be aware that 

fish were even present in the stocked lakes. Some visitors might notice the fish 

but not realize they were nonnative and may probably react indifferently. The 

impacts on the wilderness value of naturalness for these visitors would be 

negligible with regard to fishery management because they would encounter 

what they perceive to be “pristine” natural conditions in most of the wilderness. 

Those with an anthropocentric perspective (valuing human use and enjoyment of 

wilderness) would experience long-term moderate adverse impacts under 

alternative C due to the loss of fishable lakes in the national park; however, 

fishing opportunities would still remain in wilderness areas in the national 

recreation areas. Some of those with an anthropocentric perspective would view 

the application of a science-based adaptive management plan as a negligible 

impact, and some would view this as beneficial over the long term. 

On the other hand, some informed wilderness users would be aware of nonnative 

fish in the lakes due to stocking. They would also experience the indirect impacts 

of angling, such as social trails along lakeshores, fire rings, and lost or discarded 

fishing tackle and equipment. The magnitude of adverse impact would vary 

among individuals. Those with strong biocentric views of wilderness would 

continue to experience long-term major adverse impacts from continued stocking 

of fish in the national recreation area lakes. Some with a biocentric perspective 

would view the application of a science-based adaptive management plan as 

beneficial over the long term. 
E NVIRONMENTAL C ONSEQUENCES

412 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Some people may not have to experience these impacts firsthand to be adversely 

affected. Without ever visiting the North Cascades Complex, these individuals 

would be adversely impacted simply by knowing that the naturalness of the 

North Cascades Complex was being impacted by fishery management actions 

under alternative C. The magnitude of impact is unknown. 

Cumulative Impacts

The flooding in October 2004 destroyed most of the upper portion of the 

Stehekin Valley Road. For the foreseeable future, access to various portions of 

the Stehekin Valley may take much longer and may exclude some visitors from 

accessing portions of the area. Most mountain lake anglers are used to hiking 

long distances, often off trail, to access lakes, so the cumulative impact on fishing 

opportunities in mountain lakes from reduced access would likely be negligible 

over the short and long terms. 

Stocked and some reproducing populations of fish would remain in national 

recreation area lakes and potentially some national park lakes where complete 

fish removal may not be feasible (refer to table 7 in the “Alternatives” chapter). 

This would be a long-term major adverse cumulative impact for those who 

believe that the continued stocking (as proposed under alternative C) in 

wilderness and continued presence of reproducing populations of fish would 

compromise natural processes. There would be a long-term negligible cumulative 

impact on those who believe that human use and enjoyment of wilderness should 

continue. Depending on one’s views regarding the application of science-based 

adaptive management principles in wilderness areas, cumulative impacts either 

would be beneficial or adverse over the long term. Fishery management actions, 

especially fish removal, would impose an administrative presence in wilderness, 

in addition to established administrative actions such as research and monitoring, 

ranger patrols, and fire management actions. Taken together, these additional 

fishery management actions would have a minor adverse cumulative impact on 

solitude over the long term. 

Compared to alternatives A and B, there would be long-term moderate beneficial 

cumulative impacts on wilderness values due to the cessation of stocking and 

removal of fish from the study area lakes in the national park. 

Conclusion 

Backpack stocking would have a negligible direct impact on visitor solitude over 

the long term. Given the short-term and infrequent nature of fixed-wing aircraft 

stocking, there would be a short- and long-term minor adverse impact on 

opportunities for solitude. Sport-fishing opportunities would be eliminated, 

where feasible, in the national park lakes and would continue to exist in select 

national recreation area lakes. This would result in a moderate beneficial impact 

on opportunities for solitude over the long term in some areas. However, some 

lakes in certain high-use areas would remain fishable, resulting in minor adverse 

impacts on opportunities for solitude over the long term. The impacts on solitude 

from fish-removal activities would be minor to moderate and adverse over the 

long term. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 413

Anglers who choose to fish elsewhere due to the reduced fishing opportunities 

would experience long-term minor adverse impacts. Anglers who believe the 

fishing experience cannot be duplicated elsewhere would experience long-term 

major adverse impacts. Impacts on other visitors’ opportunities for primitive 

recreation in high-use areas over the summer would be minor to moderate 

adverse over the long term. 

Those with an anthropocentric perspective (valuing human use and enjoyment of 

wilderness) would experience long-term moderate adverse impacts under 

alternative C due to the loss of fishable lakes in the national park; however, 

fishing opportunities would still remain in wilderness areas in the national 

recreation areas. Some of those with an anthropocentric perspective would view 

the application of a science-based adaptive management plan as a negligible 

impact, and some would view this as beneficial over the long term. Those with 

strong biocentric views (support protection of natural processes in wilderness 

areas) of wilderness would experience long-term major adverse impacts from the 

fishery management actions under alternative C. Some with biocentric 

perspectives would view the application of a science-based adaptive management 

plan as beneficial over the long term. Impacts are wilderness users who are not 

aware that fish are present in the lakes would be negligible over the long term. 

Cumulative impacts on fishing opportunities in mountain lakes from reduced 

access would likely be negligible over the short and long terms. 

There would be a long-term major adverse cumulative impact on those who 

believe that the stocking proposed under alternative C and continued presence of 

reproducing populations of fish would compromise natural processes in 

wilderness. There would be long-term negligible cumulative impacts on those 

who believe that human use and enjoyment of wilderness should continue. 

Depending on one’s views regarding the application of science-based adaptive 

management principles in wilderness areas, cumulative impacts either would be 

beneficial or adverse over the long term. Fishery management actions, including 

fish removal, would have long-term minor adverse impacts on solitude. Due to 

the cessation of stocking in the national park, moderate beneficial cumulative 

impacts would be expected on wilderness values over the long term. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Alternative D would eventually eliminate the mountain lakes fishery in the North 

Cascades Complex. The “Alternatives” chapter provides a detailed description of 

alternative D. For more information on the 91 lakes, refer to tables 5 and 13 in 

the “Alternatives” chapter and appendix E. 

Impacts on Opportunities for Solitude 

All stocking in the North Cascades Complex would cease. Compared to 

alternative A, this would cause moderate to major beneficial impacts on 

opportunities for solitude over the long term due to the decreased use of high 

mountain lakes for fishing. 
E NVIRONMENTAL C ONSEQUENCES

414 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Management actions related to fish removal include the use of chemical 

treatments (piscicides) and mechanical treatments, which would require the use 

of helicopters, motorized boats, electrofishing gear, gillnetting, and the routine 

presence of crews at select lakes. Gillnetting and piscicide application would 

require use of a helicopter to ferry heavy gear and the use of electrofishing gear 

to supplement netting. Removal with piscicides would be limited to one lake at 

time and probably only one or two lakes would be treated per season. Gillnetting 

would occur at several lakes at one time, depending on the availability of 

personnel and equipment. The noise and visual disturbance from these 

management actions would affect the solitude at lakes undergoing treatment and 

in areas along the flight path of helicopters or the access routes. Helicopter use 

would be limited to a few flights in a few locations over the course of a season. 

To minimize impacts on visitor solitude, NPS staff issuing backcountry overnight 

use permits would encourage users to visit areas not undergoing fish-removal 

actions. Taken together, the impacts on solitude from fish removal activities 

would be long term, minor to moderate adverse because most of the wilderness 

would remain unaffected by fish-removal actions. 

Fishery management actions would eliminate sport-fishing opportunities in the 

study area lakes; however, fishing opportunities would be available in the 

foreseeable future while lake treatment activities were completed. In addition, 

fishing opportunities would still remain in the reservoirs, rivers, and some 

streams throughout the North Cascades Complex. 

Compared to alternative A, opportunities for solitude would increase in the 

wilderness because there would be fewer anglers present to disrupt the solitude of 

other wilderness users. This would be a long-term moderate to major beneficial 

impact. Fishing opportunities would be available in the nine large, deep lakes 

identified in table 7 where complete fish removal may not be feasible. Near those 

nine lakes, sport-fishing activities would affect opportunities for solitude, and 

this would result in a minor adverse impact over the long term for some visitors. 

Impacts on 

Opportunities for Primitive Recreation 

Over time, all lakes with self-sustaining populations or stocked populations of 

fish would become fishless, and the overall opportunity for fishing in the 

wilderness would be eliminated. Compared to alternative A, loss of fishing 

opportunity would have a major adverse impact on mountain lake anglers. Some 

anglers may simply fish elsewhere, and impacts on these anglers would be long 

term and minor. Other anglers believe that the lakes in North Cascades Complex 

offer a unique fishing opportunity that cannot be duplicated elsewhere; these 

anglers would experience long-term major adverse impacts from lost fishing 

opportunity. It is noted that some illegal stocking has occurred in the past and 

may continue to occur under alternative D, although it is impossible to quantify 

the degree to which illegal stocking has occurred or may occur in the future. 

The cessation of anglers fishing at lakes in the Stephen T. Mather Wilderness 

would result in long-term beneficial impacts on other visitors because it may 

increase the availability of backcountry overnight use permits. 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 415

Impacts on Naturalness 

Alternative D would remove all fish from the 62 study area lakes that currently 

contain fish. These actions would eliminate, where feasible, the existence of a 

nonnative, artificial fishery in mountain lakes that were naturally fish free and 

would therefore restore the value of naturalness in the Stephen T. Mather 

Wilderness. The magnitude of the impact would depend upon individual 

perception and experience. 

Some wilderness users would not be aware that fish were removed from the 

lakes. The impacts on the wilderness value of naturalness for these visitors would 

be negligible over the long term. Those with an anthropocentric perspective 

(valuing human use and enjoyment of wilderness) would experience major longterm adverse impacts under alternative D. Some of those with an anthropocentric 

perspective would view the application of a science-based adaptive management 

plan to remove fish as a negligible impact, and some would view this as 

beneficial. 

On the other hand, some informed wilderness users would be aware that fish had 

been removed. They would no longer experience the indirect effects of angling, 

such as social trails along lakeshores, fire rings, and lost or discarded fishing 

tackle and equipment. The magnitude of impact would vary among individuals. 

Those with strong biocentric views (support protection of natural processes in 

wilderness areas) of wilderness would experience major long-term beneficial 

impacts because all fish would be removed under alternative D. Some with a 

biocentric perspective may view the application of a science-based adoptive 

management plan as beneficial over the long term. 

Some people would not even have to experience these impacts firsthand to be 

beneficially affected. Without ever visiting the North Cascades Complex, these 

individuals would be beneficially impacted simply by knowing that the 

naturalness of the North Cascades Complex was being protected and restored. 

The magnitude of impact is unknown. 

Cumulative 

The flooding in October 2003 destroyed most of the upper portion of the 

Stehekin Valley Road. For the foreseeable future, access to various portions of 

the Stehekin Valley may take much longer and may exclude some visitors from 

accessing portions of the area. Most mountain lake visitors are used to hiking 

long distances, often off trail, to access lakes, so the cumulative impact to 

mountain lake visitors from reduced access would likely be negligible over the 

short and long terms. 

Compared to alternative A, there would be long-term major beneficial 

cumulative impacts on those who believe that continued stocking in wilderness 

and continued presence of reproducing populations of fish would compromise 

natural processes. There would be long-term major adverse cumulative impacts 

on anglers who believe that human use and enjoyment of wilderness should 

continue. Depending on one’s views regarding the application of science-based 

adaptive management principles to remove fish from wilderness areas, 

cumulative impacts either would be beneficial or adverse over the long term. 
E NVIRONMENTAL C ONSEQUENCES

416 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Fishery management actions, especially fish removal, would impose an 

administrative presence in wilderness, in addition to established administrative 

actions such as research and monitoring, ranger patrols, and fire management 

actions. Taken together, these additional fishery management actions would have 

a minor adverse cumulative impact on opportunities for solitude over the long 

term. Due to the cessation of stocking, long-term moderate to major beneficial 

cumulative impacts on wilderness values would be expected. 

The displacement of anglers to other wilderness areas would result in negligible 

adverse impacts, even if all anglers decided to fish elsewhere. 

Conclusion 

Sport-fishing opportunities would be vastly reduced compared to alternative A 

because all stocking in the North Cascades Complex would cease, and fish would 

be removed from all lakes. This would result in long-term moderate to major 

beneficial impacts on opportunities for solitude in areas where fishing 

opportunities would be eliminated. However, fishing opportunities would 

continue to exist in the nine deep lakes where complete fish removal may not be 

feasible, resulting in long-term minor adverse impacts on opportunities for 

solitude. 

Impacts on solitude from fish removal activities would be minor to moderate and 

adverse over the long term. 

Anglers who choose to fish elsewhere because of reduced fishing opportunities 

would experience long-term minor adverse impacts. Anglers who believe the 

fishing experience cannot be duplicated elsewhere would experience long-term 

major adverse impacts. 

The cessation of anglers using wilderness would result in long-term beneficial 

impacts on other visitors. 

Those with an anthropocentric perspective (valuing human use and enjoyment of 

wilderness) would experience long-term major adverse impacts under 

alternative D. Some of those with an anthropocentric perspective would view the 

application of a science-based adaptive management plan to remove fish as a 

negligible impact, and some would view this as beneficial. 

Those with strong biocentric views (support protection of natural processes in 

wilderness areas) of wilderness would experience long-term major beneficial 

impacts because all fish would be removed (where feasible) under alternative D. 

Some with a biocentric perspective would view the application of a sciencebased adaptive management plan as beneficial over the long term. Impacts on 

those wilderness users who would not be aware that nonnative fish have been 

removed from the lakes would be negligible over the long term. 

Cumulative impacts on fishing opportunities in mountain lakes from reduced 

access would likely be negligible over the short and long terms. There would be 

long-term major beneficial cumulative impacts on those who believe that the 

continued stocking in wilderness and continued presence of reproducing 
Visitor Use and Experience 

ENVIRONMENTAL IMPACT STATEMENT 417

populations of fish would compromise natural processes. There would be longterm major adverse cumulative impacts on anglers who believe that human use 

and enjoyment of wilderness should continue. Depending on one’s views 

regarding the application of science-based adaptive management principles to 

remove fish from wilderness areas, cumulative impacts either would be 

beneficial or adverse over the long term. Fishery management actions, including 

fish removal, would have long-term minor adverse cumulative impacts on 

solitude. Due to the cessation of stocking, long-term moderate to major beneficial 

cumulative impacts on wilderness values would be expected. 

The displacement of anglers to other wilderness areas would result in long-term 

negligible adverse cumulative impacts, even if all anglers decided to fish 

elsewhere.
418 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

HUMAN HEALTH 

Human health issues potentially affected by the proposed alternatives include 

potential exposure to antimycin through consumption of chemically treated 

stocked fish and potential exposure to methyl-mercury and persistent organic 

pollutants through consumption of contaminated fish. Impacts would occur from 

stocking or fish removal activities under the proposed management actions (refer 

to tables 4 and 5 in the “Alternatives” chapter). 

This section describes the methods used to analyze impacts on human health and 

results of the analysis. The following section discusses the regulations and 

policies used to guide NPS decision-making, in addition to the assumptions and 

thresholds used to analyze impacts on human health. 

GUIDING REGULATIONS AND POLICIES 

Servicewide NPS regulations and policies emphasize protection of human health 

in all park operations and visitor activities. NPS Management Policies state that 

the NPS will seek to provide a safe and healthful environment for visitors and 

employees, and that NPS will reduce or remove known hazards and apply other 

appropriate measures, including closings, guarding, signing, or other forms of 

education to do this (NPS 2001a, 8.2.5). 

The U.S. Environmental Protection Agency (EPA) has guidance that provides 

benchmarks for concentrations of organic contaminants in fish to avoid elevated 

cancer risk in consumers (EPA 2004). These include recommended benchmarks 

for levels of methyl-mercury and other persistent organic pollutants in fish for 

protection of human health. 

METHODOLOGY AND ASSUMPTIONS 

The following discussion describes the methodology used to evaluate the impacts 

on human health that could result from implementation of any of the proposed 

alternatives. Analysis methods are qualitative and are based on reviews of 

existing data and literature and best professional judgment. The analysis 

presented in this section assumes that the historic and current stocking of trout in 

high mountain lakes has created favorable conditions for human take and 

consumption of stocked fish. 

I MPACT T HRESHOLD D EFINITIONS

The following thresholds were used to determine the magnitude of impacts on 

human health as a result of implementation of any of the alternatives, including 

stocking and treatment methods: 

Negligible: The impact on human health would not be measurable or perceptible. 
Human Health 

ENVIRONMENTAL IMPACT STATEMENT 419

Minor: The impact on human health would be measurable or perceptible, but it 

would be limited in effect. 

Moderate: The impact on human health would be sufficient to cause noticeable 

effects to human health. 

Major: The impact on human health would be substantial, resulting in 

substantial, noticeable effects to human health. 

IMPACTS OF THE 

ALTERNATIVES ON HUMAN HEALTH 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A (no action) would continue existing management of the 91 lakes in 

the study area. The “Alternatives” chapter provides a detailed description of 

alternative A. For more information on the 91 lakes, refer to table 5 and figure 4 

in the “Alternatives” chapter and appendix E. 

Impacts of Current 

Fish Stocking on Human Health 

The majority of impacts on human health under alternative A would be related to 

the age of the fish, number of fish stocked, and/or density of reproducing fish in 

the lakes (refer to table 6 in the “Alternatives” chapter). In the 62 lakes under 

alternative A that have been stocked with fish, direct adverse impacts on human 

health from consuming fish exposed to persistent organic pollutants or methylmercury would be negligible. Twenty-eight different organochlorine compounds 

were analyzed for lakes sampled in the North Cascades Complex, and only two 

were observed—total PCBs (polychlorinated biphenyl) and DDE 

(dichlorodiphenyldichloroethylene)—at concentrations below Food and Drug 

Administration Action Levels for fish tissue of 2 and 5 milligrams per kilogram 

(mg/kg), respectively. (FDA Action Levels refer to the sale and distribution of 

goods in the market place.) Average PCB concentrations in sampled lakes 

exceeded EPA’s guideline screening value of 0.02 mg/kg for elevated cancer 

risk. The researchers caution that these fish tissue results are preliminary, and 

additional sampling is needed. Also, the EPA guidelines screening values are 

based on conservative assumptions (for example, consumption of two 8-ounce 

meals of fish per month every year over a 70-year lifetime). A high level of 

protection is built into the thresholds—lakes containing fish would continue to be 

monitored for persistent organic pollutants and methyl-mercury in fish tissue, and 

any human health concerns would be communicated to the public. 
E NVIRONMENTAL C ONSEQUENCES

420 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Impacts of Current Lake 

Treatment Methods on Human Health 

None of the 91 lakes addressed in this plan/EIS are currently treated nor would 

they be treated under alternative A; therefore, no impacts on human health would 

occur from consumption of fish exposed to piscicides. 

Cumulative Impacts 

Cumulative impacts on human health are considered for past, present, and future 

projects occurring in the North Cascades Complex or outside its boundary. No 

new major roads, trails, resorts, or major upgrades of facilities are proposed or 

are in the planning stages. Some trails were flooded, so access has been 

eliminated or reduced. Visitor use is expected to remain at about the same levels 

that it has been at for several years, resulting in similar levels of use at most lakes 

and connected streams. 

Mountain lake fisheries on National Forest System lands that surround the North 

Cascades Complex are managed by the WDFW. The department’s management 

approach, described in WDFW (2001), is expected to be similar in the 

foreseeable future to current management activities. There is concern about 

persistent organic pollutants and methyl-mercury found in these lakes, but lakes 

stocked in the past are assumed to have a range of impacts on human health 

pollutant concentrations similar to those analyzed for North Cascades Complex 

lakes, which means negligible to minor impacts under alternative A. 

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus impacts from potential airborne pollution, added to the 

impacts predicted under alternative A, would result in negligible impacts on 

human health over the long term. 

Conclusion

Alternative A would have negligible impacts on human health over the long term 

from the consumption of stocked fish that may have been exposed to persistent 

organic pollutants and methyl-mercury, and no adverse impacts on human health 

from any lake treatment chemicals since none would be used. Cumulative 

impacts on human health would be negligible adverse over the long term. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative would be to provide sport-fishing opportunities 

in approximately 29 of the 91 study area lakes, and approximately 49 lakes either 

would remain in their current fishless state or be returned to a fishless condition. 

Another 13 lakes would be evaluated prior to determining final management 

actions. Restocking of nonreproducing fish in the 13 lakes would only be allowed 

if monitoring results indicate fish are not causing major adverse impacts. 
Human Health 

ENVIRONMENTAL IMPACT STATEMENT 421

The “Alternatives” chapter provides a detailed description of alternative B. For 

more information on the 91 lakes, refer to tables 5 and 10 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed 

Fish Stocking on Human Health 

Under alternative B, impacts related to the consumption of fish potentially 

contaminated with methyl-mercury and persistent organic pollutants would be 

similar to alternative A. Reducing high densities of fish and removing fish in an 

additional 19 lakes using chemical treatment would decrease the probability of 

consumption and result in negligible impacts on human health. 

Impacts of Proposed Lake 

Treatment Methods on Human Health 

The treatment methods proposed for each lake were selected based on the type of 

fish population present (reproducing versus nonreproducing) and physical 

characteristics of the lake, such as depth and surface area (refer to appendix E for 

details about the 91 lakes). The chemical method involves application of the 

piscicide, antimycin, to 19 lakes under alternative B (refer to table 7 in the 

“Alternatives” chapter). The chemical method would be used in large lakes with 

reproducing fish populations where mechanical removal methods would not be 

practical. As described in the “Alternatives” chapter, the concentration of 

antimycin necessary to remove fish is considered to be harmless to humans 

(Rosenlund 2002). Antimycin breaks down very quickly in a fish’s body and in 

the water, reducing the likelihood of contamination if fish were caught and 

consumed (Rosenlund 2002). Also, antimycin is used in such small quantities 

that residues are extremely small, and it has not been shown to bioaccumulate 

(Schnick 1974). In addition, the NPS would implement mitigation measures to 

keep visitors and anglers away from treated lakes and to educate anglers about 

the use of antimycin and its effects on fish (see appendix I). Because of the lack 

of evidence of human health effects and the mitigation that would be used, 

impacts of fish removal using antimycin would be negligible to minor and 

adverse over the long term. Lakes containing fish would continue to be 

monitored for persistent organic pollutants and methyl-mercury in fish tissue, and 

any human health concerns would be communicated to the public. 

To ensure treated fish are not caught and consumed following chemical 

treatment, lakes would be temporarily closed to visitors, if necessary, during and 

immediately after chemical treatments until it is determined that the chemical has 

dissipated. Educational materials about treatment dates and locations would be 

posted on bulletin boards, on the North Cascades Complex website, and at visitor 

centers. Park rangers would alert visitors as to which lakes were being treated (or 

were recently treated) when backcountry overnight use permits are issued. In 

addition, educational materials would be provided to visitors explaining the 

closures and describing how to recognize fish treated with antimycin (the fish 

becomes discolored and lethargic). 
E NVIRONMENTAL C ONSEQUENCES

422 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Cumulative Impacts 

Cumulative impacts on human health under alternative B would be very similar 

to those described for alternative A, with the addition of negligible impacts on 

human health from the unlikely potential for consumption of chemically treated 

fish. Overall, the impacts associated with other projects and fishery management 

actions in the area, plus possible impacts from potential airborne pollution, added 

to the impacts predicted under alternative B, would result in negligible to minor 

adverse cumulative impacts on human health. 

Conclusion 

Alternative B would have negligible to minor adverse impacts on human health 

over the long term from stocking decisions and consumption of stocked fish that 

may have been exposed to persistent organic pollutants and methyl-mercury. 

Proposed chemical treatments that would be used to remove fish from 19 lakes 

would have negligible adverse impacts on human health over the long term. 

Cumulative impacts on human health would be negligible to minor adverse over 

the long term. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Alternative C applies a new adaptive management framework to the 91 lakes in 

the study area, wherein 9 lakes in Ross Lake and Lake Chelan National 

Recreation Areas would have fish and 2 lakes would be evaluated for restocking. 

Of the other 11 lakes in the national recreation areas, 3 would remain fishless, 

3 would have high density reproducing fish removed, and stocking would be 

discontinued in 5 lakes. The remaining 69 lakes (which are in the national park) 

would be returned to their natural fishless condition or would remain fishless. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

Impacts of Proposed 

Fish Stocking on Human Health 

The types of impacts of fish stocking on human health would be similar to those 

described for alternative A; however, under alternative C, there would be 

approximately 80 lakes that would be fishless, as opposed to 29 lakes under 

alternative A, with reductions in fish densities in other lakes. Loss of fish 

resources in these lakes would result in decreased potential of human 

consumption of fish contaminated with methyl-mercury and persistent organic 

pollutants. Impacts on human health would be negligible over the long term. 
Human Health 

ENVIRONMENTAL IMPACT STATEMENT 423

Impacts of Proposed Lake 

Treatment Methods on Human Health 

Under alternative C, the types of impacts associated with the various lake 

treatments methods would be the same as described for alternative B; however, 

the numbers of lakes affected by those treatments would increase, with slightly 

more potential for human consumption of chemically treated fish. Under 

alternative C, 25 lakes would be treated with the piscicide, antimycin, an increase 

of 6 lakes over alternative B. Impacts on human health would be negligible over 

the long term. 

Cumulative Impacts 

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus potential impacts from increased airborne pollution, 

added to the impacts predicted under alternative C, would be expected to result in 

negligible to minor cumulative adverse impacts on human health over the long 

term. 

Conclusion 

Alternative C would have negligible to minor adverse impacts on human health 

over the long term from stocking decisions and consumption of stocked fish that 

may have been exposed to persistent organic pollutants and methyl-mercury. 

Proposed chemical treatments that would be used to remove fish from 25 lakes 

would have negligible adverse impacts on human health over the long term. 

Cumulative impacts on human health would be negligible to minor adverse over 

the long term. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

The emphasis of this alternative is that 91 lakes in the study area would 

eventually be fishless. The “Alternatives” chapter provides a detailed description 

of alternative D. For more information on the 91 lakes, refer to tables 5 and 13 in 

the “Alternatives” chapter and appendix E. 

Impacts of Proposed 

Fish Stocking on Human Health 

Under alternative D, the 29 lakes that are currently fishless would remain 

fishless, and fish stocking would be gradually phased out. The lakes that 

currently have fish would be treated to remove fish over time, with the exception 

of the 9 lakes identified in table 7 where complete fish removal may not be 

feasible. Loss of fish resources in lakes would result in negligible impacts on 

human health over the long term. 

Impacts of Proposed Lake 

Treatment Methods on Human Health 

Under alternative D, the types of impacts associated with the various lake 

treatment methods would be the same as described for alternative B; however, 
E NVIRONMENTAL C ONSEQUENCES

424 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

the number of study area lakes affected by those treatments would increase, with 

more potential impacts on human health from possible consumption of 

chemically treated fish. The chemical method involving application of the 

piscicide, antimycin, would be used in 25 lakes under alternative D, the same as 

alternative C, but an increase of 7 lakes over the number that would be 

chemically treated under alternative B. Impacts on human health would be 

negligible over the long term. 

Cumulative Impacts 

Overall, the impacts associated with other projects and fishery management 

actions in the area, plus impacts from potential airborne pollution, added to the 

impacts predicted under alternative D, would be expected to result in negligible 

to minor adverse cumulative impacts on human health over the long term. 

Conclusion 

Alternative D would have negligible to minor adverse impacts on human health 

over the long term from consumption of fish from previously stocked lakes that 

may have been exposed to persistent organic pollutants and methyl-mercury. 

Proposed chemical treatments used to remove fish from 25 lakes would have 

negligible adverse impacts on human health over the long term. Cumulative 

impacts on human health would be negligible to minor adverse over the long 

term. 
ENVIRONMENTAL IMPACT STATEMENT 425

SOCIOECONOMIC 

RESOURCES 

GUIDING REGULATIONS AND POLICIES 

The National Environmental Policy Act of 1969 requires that economic and 

social impacts be analyzed in an environmental impact statement when they are 

interrelated with natural or physical impacts. Economic and social impacts would 

potentially result from the natural and physical effects of changes to fish 

populations in North Cascades Complex mountain lakes; therefore, this plan/EIS 

addresses economic and social impacts. 

METHODOLOGY AND ASSUMPTIONS 

Visitors who fish in the mountain lakes of the North Cascades Complex spend 

money in nearby communities as part of the recreational experience. Limiting or 

discontinuing the stocking program may affect the level of this spending and 

affect people who depend on it. The methodology for assessing the relative 

economic contribution of sport fishing in the study area was derived by 

estimating the annual angler numbers and applying an estimate of annual 

expenditures provided by the WDFW. Then, in order to estimate other secondary 

economic contributions from these annual expenditures to the job market and 

income, the model IMPLAN was used (see the “Socioeconomic Resources” 

section of the “Affected Environment” chapter). The impact analysis involves 

qualitatively assigning a change (increase or decrease) in anglers to each 

alternative, based on the activities under that alternative that would increase or 

decrease fish population. Then, the resulting economic effect is both qualitatively 

and quantitatively estimated. When spending in the regional or local economy is 

affected, a negligible, minor, moderate, or major impact would occur. The 

criteria for meeting these thresholds are explained below. 

G EOGRAPHIC A REA 

E VALUATED FOR I MPACTS

The regional study area for the purpose of the socioeconomic impact analysis 

includes the North Cascades Complex and Whatcom, Skagit, and Chelan 

counties in Washington State. The local study area includes the small towns near 

the North Cascades Complex that have businesses that provide supplies and 

equipment to anglers visiting the North Cascades Complex. See the 

“Socioeconomic Resources” section in the “Affected Environment” chapter for 

further details. 

I MPACT T HRESHOLD D EFINITIONS

Negligible: No measurable effect on the socioeconomic environment. 
E NVIRONMENTAL C ONSEQUENCES

426 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Minor: Only a small sector of the local and regional economies would be 

affected and would not be readily apparent. 

Moderate: A relatively small sector of the socioeconomic environment, or the 

relationship between sectors of the local and regional economies, would be 

measurably affected, but would not alter basic socioeconomic functions and 

structure. 

Major: Changes to the local and regional economies would occur and would 

become readily apparent in the form of shifts in socioeconomic functions and 

structure. In certain cases, entirely new economic sectors would be created, or 

established sectors eliminated. 

IMPACTS OF THE ALTERNATIVES 

ON SOCIOECONOMIC RESOURCES 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Impacts on the Regional Economy 

The current mountain lakes fishery management activities at the North Cascades 

Complex, which are described in the “Alternatives” chapter, would continue 

under the no-action alternative. The “Alternatives” chapter provides a detailed 

description of alternative A. For more information on the 91 lakes, refer to 

table 5 and figure 4 in the “Alternatives” chapter and appendix E. 

The estimated number of visitors to the North Cascades Complex who engage in 

sport fishing in the study area lakes is estimated at 1,000 anglers per season (refer 

to the “Fishing” section under “Visitor Use and Experience” in the “Affected 

Environment” chapter). The WDFW estimates that approximately $49.79 per trip 

is expended by those who sport fish in the state (WDFW 1996). 

Using this estimate of expenditures, and the angler use of the study area, the total 

annual expenditures of anglers to the area are approximately $50,000, with 

additional secondary (indirect) expenditures and labor income. When factoring in 

the relationship between output, jobs, and income for sport fishing associated 

with the North Cascades Complex mountain lakes fishery in the three-county 

area (Whatcom, Skagit and Chelan counties), direct economic output ($50,000 

annually) would most likely support one to two associated direct jobs and 

$10,000 in direct labor income on an annual basis (IMPLAN, Copyright 

Minnesota IMPLAN Group, Inc.). 

The total (direct plus secondary) spending attributable to recreational mountain 

lake fishing in the North Cascades Complex represents, at most, 0.001% of total 

retail sales in the three-county area, and 0.006% of total retail sales in the 

combined unincorporated areas of the three counties (WDOR 2003). Revenues 

from mountain lakes fishing, then, account for roughly $1 out of every $100,000 

spent in the three-county region. In comparison to the three-county economy as a 

whole, assuming angler use under this alternative remains steady (approximately 
Socioeconomic Resources 

ENVIRONMENTAL IMPACT STATEMENT 427

10.5% of total backcountry permit visitation) over the next 15 years, these 

expenditures would have a beneficial, yet negligible, long-term impact on the 

regional economy. 

Impacts on the Local Economy 

Local businesses would also continue to be affected over the long term (see the 

“Socioeconomic Resources” section in the “Affected Environment” for local 

businesses in the vicinity of the study area). Proprietors of local businesses on the 

west side of the North Cascades Complex that cater to fishing indicate that 

fishing of mountain lakes in the North Cascades Complex is very limited and 

accounts for a negligible portion of revenues (NPS, Roy Zipp, pers. comm., 

2004). A variety of factors appear to contribute to the limited use, including 

access difficulties, perception that fishing is prohibited, and a general lack of 

knowledge that many mountain lakes in the North Cascades Complex contain 

fish. Given the assumption that average visitation and angling use would remain 

constant over the next 15 years, local businesses on the west side would continue 

to experience beneficial, yet negligible, long-term impacts. 

Impacts on businesses in Stehekin, including the Stehekin Valley Ranch in Lake 

Chelan National Recreation Area, would also continue to be affected if current 

management of the fishery continued over the next 15 years. The relative greater 

use by anglers of the mountain lakes in the Lake Chelan National Recreation 

Area indicates the popularity of that area. Although no formal measurement of 

local expenditures by anglers who stay or pass through Stehekin is available, it is 

assumed that seasonal expenditures are higher than other local communities. For 

example, an estimated 28 guests per day visit the Stehekin Valley Ranch from 

June through August. Pack trips to Rainbow and surrounding lakes, and day trips 

to Coon Lake, would continue to be a large part of this local business. Existing 

and projected angler use in this area assumes that most anglers stay overnight and 

obtain backcountry overnight permits for an extended trip to the lakes around the 

Stehekin area. Under alternative A, expenditures of anglers who visit the ranch 

and other businesses in the area as part of their trip would continue, but are not 

expected to increase substantially. This assumption is made because the overall 

park visitation has remained steady over the past 10 years (see the “Visitor Use” 

section and table 22 in the “Affected Environment”’ chapter). 

The proprietor of the Stehekin Valley Ranch has indicated that sport fishing is a 

large part of its income. Continuing the fishery management program under this 

alternative would have a long-term beneficial impact on this local business. 

The 1995 Lake Chelan General Management Plan offers yet a different 

perspective of the reasons people visit the Stehekin area. Using data from 1992, 

the Lake Chelan General Management Plan identifies sightseeing, hiking, 

wildlife observation, photography, and bicycling as the primary visitor use 

activities for people visiting Stehekin. The 10%–12% of visitors who do visit the 

area and engage in sport fishing is a relatively small proportion of the annual 

visitation to the area (NPS 1995). Alternative A would have long-term beneficial 

impacts on local businesses in Stehekin. 
E NVIRONMENTAL C ONSEQUENCES

428 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Cumulative Impacts 

Cumulative impacts are the direct and indirect impacts of alternative A in 

combination with other impacts that are occurring to the socioeconomic 

environment. The economy in communities surrounding the North Cascades 

Complex continues to evolve as industry diversification occurs. The historic 

basis for many northwestern Washington communities is natural resource-based 

industries, such as agriculture, fishing, and timber. A downturn in timber has 

forced diversification in all three counties (Whatcom, Skagit, and Chelan) into 

manufacturing industries, as well as into the recreation and tourism industries. 

The total (direct plus secondary) spending attributable to recreational high lakes 

fishing in the North Cascades Complex represents, at most, 0.001% of total retail 

sales in the three-county area, and 0.006% of total retail sales in the combined 

unincorporated areas of the three counties (WDOR 2003). In comparison to the 

three-county economy as a whole, these expenditures would continue to have 

negligible cumulative impacts on the local and regional economies. 

Conclusion 

Alternative A would have long-term negligible impacts on the local and regional 

economies. Estimated revenues from mountain lake angling account for roughly 

$1 out of every $100,000 spent in the three-county region. The effects of 

continuation of the current fishery management program on some local 

businesses in the Stehekin area would be beneficial since some patrons may also 

engage in sport fishing in the mountain lakes located in Lake Chelan National 

Recreation Area. Expenditures associated with sport fishing in the mountain 

lakes in the North Cascades Complex would continue to have long-term 

negligible cumulative impacts on the local and regional economies. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

Impacts on the Regional Economy 

The emphasis of this alternative is to eliminate or reduce the density of 

reproducing fish from certain mountain lakes in the study area under 

alternative B. The “Alternatives” chapter provides a detailed description of 

alternative B. For more information on the 91 lakes, refer to tables 5 and 10 in 

the “Alternatives” chapter and appendix E. 

Assuming that the 13 lakes to be evaluated would all be available for fishing at 

some point in the future, a total of 42 lakes (compared to 62 lakes under 

alternative A) would be available for fishing. While this decrease in available 

lakes for angler use is apparent, the relative socioeconomic impact of angler 

expenditures would have a negligible adverse impact on the regional economy. A 

relatively small amount (roughly $1 out of every $100,000) of direct and indirect 

economic contributions to the three-county area result from the sport fishing 

expenditures of those who use the high mountain lakes in the North Cascades 

Complex. 
Socioeconomic Resources 

ENVIRONMENTAL IMPACT STATEMENT 429

Impacts on the Local Economy 

Alternative B, overall, would have a negligible impact on local businesses since 

the relative contribution of angler expenditures compared to total visitor 

expenditures is small. One business, such as the Stehekin Valley Ranch in the 

Lake Chelan National Recreation Area, notes that sport fishing in the high 

mountain lakes is very important to their livelihood. Under alternative B, six 

lakes in Lakes Chelan National Recreation Area would become fishless over 

time, and some would be treated to remove fish then re-evaluated for stocking at 

some point in the future. The Lake Chelan National Recreation Area backcountry 

use is one of the high-use areas in the North Cascades Complex. While it is 

estimated that 10.5% of backcountry users engage in sport fishing overall, should 

this use decrease, it would have long-term, major, and adverse impacts on some 

local businesses. This is a qualitative assessment, given that some businesses 

may rely on other visitor expenditures other than that of anglers. Other 

businesses may choose to transition their services to offer fishing in the Stehekin 

River as an alternative to fishing in the study area lakes. 

Day hiking to Coon Lake from Stehekin would remain a popular activity, and 

sport fishing would continue at the lake under alternative B. Proprietors who 

provide services to day hikers and angling supplies for those visiting Coon Lake 

would not be economically affected by this alternative. 

Cumulative Impacts 

Cumulative impacts would be similar to alternative A. While the number of lakes 

available for fishing would decrease under alternative B, the overall contribution 

of sport fishing to the local and regional economies would be long term and 

negligible. The 1995 Lake Chelan General Management Plan did not project any 

substantive changes in visitor use through the year 2007; therefore, cumulative 

impacts on most local businesses in Stehekin would be long term and negligible. 

Some local businesses in Stehekin who report a large dependence on sport 

fishing as a source of revenues, such as the Stehekin Valley Ranch, would 

experience a long-term, major, and adverse impact from this alternative, since 

other visitor uses are not expected to substantially increase (NPS 1995). 

Conclusion 

Although there would be a decrease in lakes available for fishing, the relative 

socioeconomic impact of angler expenditures would have a negligible, adverse 

impact on the local and regional economies. A relatively small amount (roughly 

$1 out of every $100,000) of direct and indirect economic contributions to the 

three-county area is from sport-fishing expenditures of anglers who fish at the 

high mountain lakes in the North Cascades Complex. Some local businesses in 

Stehekin that depend on sport fishing as a primary source of income would 

experience a long-term major adverse impact under alternative B. Cumulative 

impacts would be similar to alternative A. While the number of lakes available 

for fishing would decrease under alternative B, the overall contribution of sport 

fishing to the local and regional economies would be long term and negligible. 
E NVIRONMENTAL C ONSEQUENCES

430 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

The town of Newhalem 

is on State Route 20 in 

Ross Lake National

Recreation Area.

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Impacts on the Regional Economy 

Alternative C applies a new adaptive management framework to the 91 lakes in 

the study area, wherein 9 lakes in Ross Lake and Lake Chelan National 

Recreation Areas would have fish and 2 lakes would be evaluated for restocking. 

Of the other 11 lakes in the national recreation areas, 3 would remain fishless, 3 

would have high density reproducing fish removed, and stocking would be 

discontinued in 5 lakes. The remaining 69 lakes (which are in the national park) 

would be returned to their natural fishless condition or would remain fishless. 

The “Alternatives” chapter provides a detailed description of alternative C. For 

more information on the 91 lakes, refer to tables 5 and 12 in the “Alternatives” 

chapter and appendix E. 

The relative socioeconomic impact of angler expenditures would have a 

negligible adverse impact on the regional economy. A relatively small amount 

(roughly $1 out of every $100,000) of direct and indirect economic contributions 

to the three-county area is from the sport-fishing expenditures of anglers who fish 

the high mountain lakes in the North Cascades Complex. While alternative C 

would preclude sport fishing in the majority of the study area lakes, the effect of 

this decreased activity would not be measurable within the three-county area; 

hence, the impact would be long term, negligible, and adverse. 

Impacts on the Local Economy 

The relative socioeconomic impact of angler expenditures under this alternative 

would be negligible on the local economy over the long term. This is because on 

the west side of the North Cascades Complex, fishing expenditures are currently 

not substantial, and therefore, the effects of this 

alternative would not be measurable (see the 

“Socioeconomic Resources” section in the “Affected 

Environment” chapter). In the Stehekin area, the effects 

of alternative C would be the same as alternative B; that 

is, long-term negligible and adverse impacts would occur 

because the lakes in the Lake Chelan National Recreation 

Area would be managed the same under both alternatives. 

Compared to alternative A, the effects of alternative C on 

the Stehekin area from angler expenditures would have a 

negligible impact on the local economy. Angler visitation to the Stehekin area 

overall constitutes an estimated average visitation of 10% to 12% (see the 

“Socioeconomic Resources” section in the “Affected Environment” chapter). 

This average is not expected to substantially change over the next 10 years; 

therefore, the relative economic contributions of sport fishing in the Stehekin 

area would remain a small portion of total revenues. However, some local 

businesses in Stehekin who depend on sport fishing as a primary source of 

income would experience a long-term, major, and adverse impact from reduced 

fishing opportunities proposed in alternative C. 
Socioeconomic Resources 

ENVIRONMENTAL IMPACT STATEMENT 431

Cumulative Impacts 

Cumulative impacts of alternative C would be long term, negligible, and adverse 

overall to the local and regional economies. In general, angling opportunities 

would decrease under alternative C, which may force anglers to fish in other 

areas outside the North Cascades Complex. However, since the relative 

contribution of sport fishing to the local and regional economies is small, any 

shifts in angler use would be expected to result in negligible economic impacts. 

The majority of visitors to the North Cascades Complex are from the state of 

Washington, so any displacement of those visitors who also engage in sport 

fishing would most likely result in an increase in other areas in the state. This 

increase and associated expenditures (less than $50,000 direct expenditures per 

year) in other areas outside the North Cascades Complex would not be 

measurable. Cumulative impacts overall would be long term, negligible, and 

adverse. 

Cumulative impacts on the Stehekin area overall would be long term, negligible, 

and adverse. The proportion of visitors who engage in sport fishing compared to 

other uses is relatively small (10%–20%) in the Stehekin area. Some lakes in the 

study area would remain available for fishing in Lake Chelan National 

Recreation Area, and while there would be a decreased fishing opportunity 

compared to alternative A, the impacts on the local economy overall would not 

be measurable. 

Sport-fishing opportunities would decrease in the national park portion of the 

North Cascades Complex, which would contribute to an increase in the number 

of anglers who may choose to fish in the national recreation areas. This increase 

in angler visitation would have a negligible, but long-term beneficial impact on 

the Stehekin area. Some local businesses in Stehekin, however, may experience a 

long-term, major, and adverse impact from reduced fishing opportunities 

compared to alternative A because the number of lakes available for fishing in 

the Lake Chelan National Recreation Area would be reduced. 

Conclusion 

The number of lakes available for fishing would decrease under alternative C, 

and the relative socioeconomic impact of angler expenditures would have a 

negligible adverse impact on the local and regional economies. Revenues from 

mountain lakes angling in the North Cascades Complex account for roughly $1 

out of every $100,000 spent in the three-county region. Some local businesses in 

Stehekin that depend on sport fishing as a primary source of income would 

experience a long-term, major adverse impact from alternative C. Cumulative 

impacts on the local and regional economies overall would be long term and 

negligible, while some businesses in Stehekin may experience long-term, major 

adverse impacts because other visitor uses are not expected to increase 

substantially. There would be beneficial economic impacts on Stehekin area 

businesses if anglers chose to fish in the Lake Chelan National Recreation Area 

since fishing in the mountain lakes outside of the national recreation areas would 

be eliminated. 
E NVIRONMENTAL C ONSEQUENCES

432 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Impacts on the Regional Economy 

The goal of this alternative is that the 91 lakes in the study area would eventually 

be fishless. Sport-fishing opportunities in most of these lakes would generally be 

eliminated within a period of 5 years, and self-sustaining (reproducing) 

populations of fish would be gradually removed over time. The rate of removal 

would depend on unpredictable changes in resource (funding and personnel) 

availability and differences among fish removal methods. Complete removal of 

self-sustaining populations of fish in some of the larger, deeper lakes might not 

be feasible (9 lakes potentially fall into this category—refer to table 7). These 

lakes would continue to provide sport-fishing opportunities for the foreseeable 

future, and the goal of complete removal might never be achieved. The 

“Alternatives” chapter provides a detailed description of alternative D. For more 

information on the 91 lakes, refer to tables 5 and 13 in the “Alternatives” chapter 

and appendix E. 

This alternative would result in lost income, both direct and indirect, to the 

regional economy. Overall, while the relative contribution to the regional 

economy from sport fishing in the 91 lakes is small compared to alternative A, 

the impact of these lost expenditures would be long term, minor, and adverse. 

Impacts on the Local Economy 

Removal of all fishing opportunities in the study area lakes would have a longterm, minor, adverse impact on the local economy compared to alternative A. 

While the relative contribution of angler expenditures to local businesses is 

small, compared to alternative A, the loss of sport fishing in the high mountain 

lakes in the study area would be measurable but minor. Loss of all fishing 

opportunities in the mountain lakes in the Lake Chelan National Recreation Area 

would have a minor adverse impact on local businesses in Stehekin, since the 

revenues of sport fishing are relatively small compared to other revenue sources; 

however, some businesses that depend on sport fishing in the study area lakes in 

the Lake Chelan National Recreation Area would experience a long-term, major, 

and adverse impact. 

Cumulative Impacts 

The negligible but adverse direct and indirect long-term socioeconomic impact of 

alternative D, in combination with the long-term growth and diversification the 

region has experienced recently, would result in a long-term, negligible, and 

adverse cumulative impact. Cumulative impacts on the local economy, overall, 

would also be long term, negligible, and adverse because the relative contribution 

of sport fishing expenditures related to the mountain lakes in the study area is 

small. Some businesses in Stehekin may experience long-term, major adverse 

impacts from loss of this revenue source. 
Socioeconomic Resources 

ENVIRONMENTAL IMPACT STATEMENT 433

Conclusion 

Overall, the local and regional economies would experience long-term negligible 

to minor adverse impacts from the elimination of sport fishing in the mountain 

lakes in the study area. Compared to alternative A, some Stehekin businesses 

would experience long-term major adverse impacts under alternative D if their 

primary source of income is from anglers who fish in the study area lakes. 

Cumulative impacts, overall, would be long term, negligible, and adverse. 
434 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

MANAGEMENT 

AND OPERATIONS 

GUIDING REGULATIONS AND POLICIES 

Direction for the North Cascades Complex management and operations is set 

forth in the park’s enabling legislation, General Management Plan (NPS 1988b), 

and Strategic Plan (NPS 2000a). Specifically related to the proposed mountain 

lakes fishery management plan, the General Management Plan includes the 

following management objectives: 

Provide the minimum NPS development necessary to provide essential 

services to visitors and to facilitate environmentally sound and resourceoriented recreational use. 

Cooperate with other governmental agencies, private organizations, local 

residents, and members of the public in (1) ensuring that land uses within 

and adjacent to the designated parklands are compatible, to the greatest 

degree possible, with preservation of the resource values; (2) providing 

adequate information to visitors on the recreational, interpretive, and 

educational opportunities as well as the visitor services available in the 

North Cascades; (3) developing programs for managing vegetation, 

wildlife, and fisheries; and (4) developing plans and programs for dealing 

with all other problems of mutual concern. 

The Strategic Plan also contains strategies and long-term goals that describe 

management and operational objectives through September 30, 2005. 

METHODOLOGY AND ASSUMPTIONS 

A long-term commitment of funding and personnel would be needed to manage 

the mountain lakes fishery. Table 30 in the “Affected Environment” chapter 

provides the annual base funding the park has received over the past 12 years. All 

of the alternatives were analyzed assuming the current trend shown in table 30 of 

minimal increase in the park’s annual budget would continue over the next 

15 years. Though innovative partnerships and non-NPS funding may be available 

as a means of limiting NPS costs, impacts on park operations were analyzed with 

the assumption that NPS funding and personnel would be required to carry out 

the majority of management actions, especially monitoring and fish removal. 

To accomplish monitoring and fish removal, a field crew of biological 

technicians composed of a team leader (term position) and three assistants 

(seasonal positions) would be hired provided soft funding could be obtained. 

These personnel would primarily be responsible for field work during the 

summer months. Existing staff at the park would supervise these employees and 

provide overall project management as part of existing park operations. 
Management and Operations 

ENVIRONMENTAL IMPACT STATEMENT 435

For management alternatives that include stocking (alternatives A, B, and C), it 

was assumed that the WDFW and their stakeholders would continue to stock 

lakes with no direct cost to the NPS. 

Personnel costs were developed with the assumption that both 

permanent and seasonal NPS staff would be required to manage the 

mountain lakes fishery. Funding for resource management staff in 

the North Cascades Complex covers salaries and provides for a 

small amount of discretionary monies for ongoing, high-priority 

resource management projects. To fully implement each of the 

adaptive management alternatives presented in this plan/EIS, 

additional funding and personnel would be needed. Various sources 

of “soft” funding are available through the NPS but only on a 

competitive basis and typically for a maximum of three years. 

Costs of fish removal using gillnets were calculated using data from 

ongoing fish removal efforts in Sequoia-Kings Canyon National 

Park, California. That program developed a successful, intensive 

gillnetting approach on small lakes (less than 5 acres) that currently 

costs approximately $15,000 per 1 acre of lake surface area (NPS, D. Boiano, 

pers. comm., 2003). Differences between Sequoia-Kings and North Cascade 

Complex lakes in terms of lake morphometry (shape and structure of lakes) and 

other logistical constraints could make the overall cost of gillnetting higher in the 

North Cascades Complex, but the uncertain costs of these confounding factors 

were not calculated into the analyses. 

The current cost of antimycin ($450/unit) was used to help develop treatment 

costs. Antimycin application costs were derived in part from antimycin treatment 

methods conducted on lakes in Rocky Mountain National Park. The calculations 

for estimating antimycin treatment costs are heavily dependent on an accurate 

understanding of lake volumes and residence times of water in the lakes. Because 

some estimates must use simplified assumptions of lake volumes and residence 

times, actual costs of lake treatments with antimycin could vary considerably 

from the estimates provided in the analysis. 

G EOGRAPHIC A REA

E VALUATED FOR I MPACTS 

The geographic area evaluated for impacts on North Cascades Complex 

management and operations includes the north and south units of the North 

Cascades National Park, the Ross Lake National Recreation Area, and the Lake 

Chelan National Recreation Area. 

I MPACT T HRESHOLD D EFINITIONS

Negligible. An action would have a no measurable impact on operations in the 

North Cascades Complex. 

Minor. Actions with minor impacts would affect operations in the North 

Cascades Complex in a way that would be difficult to measure. The impacts on 

the resources management budget and workload would be short term, with little 

material effect on other ongoing resources management programs. 

Helicopters are often 

needed as the minimum 

tool to transport heavy 

sampling gear and timesensitive samples to and 

from remote lakes. This 

photo shows NPS and 

USGS-Water Resources 

Division biologists 

sampling fish in 

Wilcox/Lillie, Upper Lake 

to detect persistent organic 

pollutants and methylmercury in fish tissue. 
E NVIRONMENTAL C ONSEQUENCES

436 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Moderate. Actions with moderate impacts would measurably affect operations in 

the North Cascades Complex. Resources management staff workloads and 

priorities would need to be rearranged to implement mountain lakes fishery 

management actions, and as a result, ongoing science and/or stewardship 

programs would be reduced in scope or potentially eliminated. 

Major. Management actions would affect resource management operations in the 

North Cascades Complex. Funding for management actions would exceed the 

current resource management budget by 10%, consume all discretionary funding, 

and require additional personnel over and above what would normally be 

expected to be funded. 

IMPACTS OF THE MANAGEMENT 

ALTERNATIVES ON NORTH CASCADES 

COMPLEX MANAGEMENT AND OPERATIONS 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

The current mountain lakes fishery management activities at the North Cascades 

Complex would continue under the no-action alternative. The “Alternatives” 

chapter provides a detailed description of alternative A. For more information on 

the 91 lakes, refer to table 5 and figure 4 in the “Alternatives” chapter and 

appendix E. 

The costs of continuing to manage mountain lakes under alternative A would be 

primarily associated with stocking, very limited monitoring, and project 

oversight. These actions would cost approximately $18,000 per year and 

primarily be borne by the WDFW. Over a 15-year period, not accounting for 

other factors such as inflation, estimated costs to implement alternative A would 

be $270,000. The North Cascades Complex would continue to receive, on an 

irregular basis, NPS funds for periodic monitoring and research projects and 

funds from constituency groups to support park programs. These supplemental 

funds would probably be minimal. Given that the annual base funding for the 

North Cascades Complex (refer to table 30 in the “Affected Environment” 

chapter) is not expected to substantially increase, the expenditure of funds to 

support alternative A would be negligible in the long term. 

Impacts of Current 

Fish Stocking on North Cascades 

Complex Management and Operations 

Alternative A would require little NPS oversight because the cost of management 

actions would continue to be largely borne by the WDFW and their stakeholders. 

No additional NPS staff or funding would be needed because no intensive 

monitoring or fish removal projects would be undertaken; therefore, the impacts 

of alternative A would be negligible and long term. 
Management and Operations 

ENVIRONMENTAL IMPACT STATEMENT 437

Impacts of Current Fish Removal 

on North Cascades 

Complex Management and Operations 

Fish removal is not part of current management, so there would be no cost or 

impact. 

Cumulative Impacts 

North Cascades Complex budgets, overall, are continuing to be stretched by 

increased public visitation, resource protection needs, and growing needs to 

improve infrastructure. The most recent flooding during the fall of 2004 is an 

example of an unexpected natural event that has cumulative impacts on North 

Cascades Complex management and operations. These types of events, as well as 

other demands on park operations, would continue. Cumulative impacts on 

operations and management would be negligible to minor and adverse over the 

long term. 

Conclusion 

Alternative A would have a negligible to minor adverse impact on management 

and operations over the long term. Total implementation costs would be 

$270,000 over a 15-year period and would primarily be borne by the WDFW. 

Average annual costs would be approximately $18,000 per year. 

Cumulative impacts would be negligible to minor and adverse over the long 

term. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

The emphasis of this alternative would be to eliminate or reduce self-sustaining 

fish populations from naturally formed mountain lakes in the North Cascades 

Complex. Some lakes would be restocked with nonreproducing fish at low 

densities once reproducing fish have been removed. Fish stocking would be 

allowed only where biological integrity could be conserved. Lakes where critical 

information is missing would not be stocked until that information becomes 

available. It is assumed that future stocking would continue to be funded and 

implemented by the WDFW and their stake holders with no additional cost to the 

NPS over the long term. An extensive monitoring program (see appendix F) 

would be implemented in order to enable adaptive management and ensure 

conservation of biological integrity over the long term. 

The “Alternatives” chapter provides a more detailed description of alternative B. 

For more information on the 91 lakes under consideration in this plan, refer to 

tables 5 and 10 in the “Alternatives” chapter and appendix E. 
E NVIRONMENTAL C ONSEQUENCES

438 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

Fish removal with gillnets would involve initial start-up costs for durable 

equipment and materials, including gillnets and electrofishing gear (see table 34). 

Most of the costs of gillnetting would involve personnel time because gillnetting 

is a very labor-intensive process. Removing fish with antimycin would be less 

labor intensive than gillnetting. Labor costs would be limited to antimycin 

application and pre- and post-treatment monitoring of native biota. The cost of 

antimycin would be one of the most expensive components, particularly for 

larger lakes because relatively large volumes of antimycin would be needed for 

lake treatment. Fish in lakes less than 5 acres would be removed with a 

combination of intensive gillnetting, trapping, and electrofishing of inlet and 

outlet streams. Lakes larger than 5 acres would be chemically treated with the 

piscicide antimycin. The acreage criterion for selecting fish removal methods 

could change if other less costly/labor-intensive methods become available, or if 

other factors such as lake depth and amounts of woody debris render gillnetting 

infeasible. 

TABLE 34: ESTIMATED TOTAL COSTS OF THE FISHERY MANAGEMENT PROGRAM UNDER ALTERNATIVE B 

This table shows detailed costs for the first three years of fish removal using gillnets and antimycin. Estimated costs for antimycin 

assume treatment at 8 parts per billion, plus possible re-treatment, if needed. Equipment needs are based on fish removal work 

performed in other national parks. 

Item Description Year I Year 2 Year 3 

GS-7/9 Crew Leader, term appointment subject furlough 

(8-months/year) 

$22,400 $23,300 $24,400 

3-GS-5 Biological Technicians (4 month seasonal appointments) $25,300 $26,400 $27,500 

Personnel 

Technical assistance with pre-treatment monitoring and antimycin 

application 

 $11,000 

Gillnets: 15 per lake (60 nets, $300 each) plus two extra in years 2 

and 3 

$18,000 $1,000 $1,000 

Antimycin ($450/unit; up to 56 units for Middle Blum and 22 units 

for Lower Blum. 

0 $35,100 0 

Three float tubes and five neoprene chest waders $900 0 0 

Two LR-24 Electrofishers (battery powered, 24-volt backpack 

mounted) 

$9,100 0 0 

Electrofisher accessories (2 each) 

(6-foot, one-piece anode pole and ring, rat-tail cathode, 24 volt 

7Ah sealed battery, BC-24PS battery-charger, 10KV electrical 

safety gloves [4]) 

$2,900 0 0 

Two Knaack boxes for storing gear on site $1,000 0 0 

Supplies 

and 

Equipment 

Backpacks, sleeping bags, tents, camping gear, and field supplies $6,000 $1,000 $1,000 

Services Zooplankton and macroinvertebrate sample analyses $12,000 $13,000 $14,000 

Helicopter ($600/hour, minimum 2-hour flights per lake to ferry 

equipment and personnel; two extra flights needed in year 2 to 

treat Blum Lake) 

Travel and $9,600 $12,000 $9,600 

Transport

Per diem $1,200 $2,000 $1,300 

Training Aviation training, pesticide applicator training $2,000 $4,000 $2,000 

Public 

Outreach 

and 

Education 

Develop interpretive media (exhibit, web page, brochure) and work 

with news media 

$6,900 $4,500 $4,900 

Total Annual Costs: $117,300 $133,300 $85,700 

Average Annual Program Cost: $112,100 

Total costs for first three years of program implementation $336,300 
Management and Operations 

ENVIRONMENTAL IMPACT STATEMENT 439

Fish in lakes with very limited spawning habitat (such as Wilcox/Lillie, Upper 

Lake) would also be removed by breaking the cycle of reproduction indirectly 

through spawning habitat exclusion. This method, however, has only been 

selected for one lake at this point due to uncertainty of success. 

The estimated costs of using gillnets and antimycin for fish removal under 

alternative B are provided in table 35. Seven lakes have been identified for the 

first round of fish removal using these various methods (highlighted in gray in 

table 35). It is assumed that it would take three years to remove fish from these 

six lakes, and success in fish removal efforts would be monitored and evaluated 

before the next round of lakes would be chosen for fish removal. Based on 

results, the methods and associated costs could vary from those indicated in 

table 35 as personnel gain experience, and innovative fish removal methods 

potentially become available. 

Table 34 shows that the estimated annual costs of alternative B for the first three 

years of program implementation would be approximately $336,300. As 

experience is gained in lake treatment methods, larger lakes would undergo fish 

removal. Costs would increase because removal methods would become more 

difficult and time-consuming to implement, and larger volumes of antimycin 

would be needed for those lakes selected for chemical treatment. Therefore, the 

estimated annual costs after the first three years would increase to approximately 

$150,000. Without funding, the impact on park operations would be minimal 

because no additional fishery management actions would be performed. 

Given the number of lakes to be treated, monitored, evaluated, and restocked in 

alternative B, a conservative estimate of total costs over the next 15 years would 

be approximately $2.14 million (NPS, R. Zipp, pers. comm., 2004). This total 

cost estimate assumes that all lakes could be treated within 15 years. This 

assumption may be too ambitious given the uncertainty of funding to implement 

the fishery management plan and the low feasibility of removing fish from larger, 

deeper lakes. 

As noted previously under “Methodology and Assumptions,” if the funding for 

the North Cascades Complex remains at current levels, fishery management 

actions could not be paid for with base funding because it is specifically 

earmarked for base operations. Base funding levels have remained static in recent 

years (refer to table 30 in the “Affected Environment” chapter), while costs have 

risen due to inflation, cost of living increases, and other factors. This trend 

underscores the point that there are few discretionary dollars available to fund 

additional resource management programs such as a fishery management plan. 

Assuming this static trend continues, then reliance upon soft funding from the 

sources noted previously would be essential for plan implementation. 

The impact of alternative B on management and operations would depend on the 

amount of soft funding received to implement the fishery management plan. 

Reliance on soft funding sources would mean that fishery management actions 

would be implemented in a piecemeal fashion and be subject to the unpredictable 

availability of funding for the foreseeable future. At a minimum, NPS resource 

management personnel would routinely have to write funding proposals and 

secure soft funding and develop and maintain partnerships to ensure that steady 
E NVIRONMENTAL C ONSEQUENCES

440 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

TABLE 35: ESTIMATED COSTS OF FISH REMOVAL FOR MANAGEMENT ACTIONS UNDER ALTERNATIVE B 

Note: The lakes highlighted in gray have been identified for the first round of fish removal. 

Lake Name 

NPS 

Lake Code 

Depth 

(feet) 

Area 

(acres) 

Initial Fish Removal 

Method Proposed for 

Alternative B 

Estimated Fish 

Removal Costa

Battalion MLY-02-01 16 6.3 Piscicide $94,500 

Bear MC-12-01 152 25.7 Piscicide $70,010 

Berdeen M-08-01 215 126.7 Piscicide $416,521 

Berdeen, Lower M-07-01 36 7.5 Piscicide $13,310 

Berdeen, Upper M-09-01 Unknownb 9.5 Piscicide $16,354 

Blum (Lower/West, No. 4) LS-07-01 26 6.4 Piscicide $11,771 

Blum (Largest/Middle, 

No. 3) 

M-11-01 33 12.9 Piscicide $15,622 

Bouck, Lower DD-04-01 63 10.8 Piscicide $19,404 

Dagger MR-04-01 16 8.2 Piscicide $11,248 

Dee Dee, Upper MR-15-01 89 12.2 Gillnet $25,460 

Diobsud No. 1 LS-01-01 11 1 Gillnet $15,000 

Diobsud No. 2, Lower LS-02-01 17 3.1 Gillnet $46,500 

Doubtful CP-01-01 68 30.2 Piscicide $42,496 

Doug's Tarn M-21-01 10 5 Gillnet $75,000 

Green M-04-01 153 80 Piscicide $193,764 

Hanging MC-08-01 33 88.8 Piscicide $55,516 

Hozomeen HM-02-01 67 97.5 Piscicide $109,008 

Kettling MR-05-01 23 9.9 Piscicide $12,681 

McAlester MR-10-01 23 13.2 Piscicide $13,808 

Monogram M-23-01 122 29.1 Piscicide $64,720 

Rainbow MR-14-01 108 15.5 Piscicide $34,159 

Skymo PM-03-01 20 10.8 Piscicide $12,508 

Sourdough PM-12-01 107 27.6 Piscicide $55,855 

Triplet, Lower SM-02-01 7 2.2 Gillnet $33,000 

Triplet, Upper SM-02-02 12 2.4 Gillnet $36,000 

 Wilcox/Lillie, Upper EP-06-01 65 10.5 Spawning habitat exclusion Volunteer labor 

Wilcox/Sandie, Lower EP-05-01 20 5.4 Gillnet $10,904 

Total estimated cost of fish removal $1,505,119 

Notes: 

a. This table provides a conservative estimate of fish removal costs for alternative B based upon the following assumptions: 

$15,000/acre for gillnetting (NPS, D. Boiano, pers. comm., 2003). Assume one-time use of piscicide antimycin per lake, $450/unit of 

Fintrol® (trade name) at 4 parts per billion, at $45 /acre-foot. Lake volume calculations assume lake basin is cone shaped (formula = 

0.33 × maximum depth x area). Treatment costs also include salary for four-person field crew ($3,000 for 2 weeks at small lake; 

$4,500 for 3 weeks at medium lake; $6,000 for 4 weeks at large lake) and helicopter transportation of equipment (2 flights small 

lake, 4 flights medium lake, 6 flights large lake). Small lakes 1–5 acres; medium lakes, 6–20 acres; large lakes 20+ acres. 

b. The depth of this lake is unknown, but for treatment purposes, a depth of 50 feet was assumed in order to calculate the cost of 

antimycin.
Management and Operations 

ENVIRONMENTAL IMPACT STATEMENT 441

sources of funding and in-kind assistance remained available to implement the 

fishery management plan. Once funding were secured, resource management 

staff would have to take on the additional burden of training personnel, assisting 

with field work, and providing overall project oversight. Interpretive staff would 

need to assist with public outreach and education to foster public understanding 

and awareness of the program. Under this likely scenario, the impacts on North 

Cascades Complex management and operations would be moderate, adverse, and 

long term because NPS personnel would have to shift workload priorities to 

accommodate these additional tasks, and other ongoing resource management 

actions may not be accomplished. 

Should NPS base funding levels increase and be made available to fund 

implementation of the fishery management plan, the adverse impacts onpark 

management and operations would decline to a minor level because (a) resources 

management staff would not have the additional burden of routinely seeking soft 

funding to implement this plan, and (b) additional resource management 

personnel could be available to manage the additional workload. Depending on 

the amount of funding available, the fishery management plan would also be 

implemented in a more holistic fashion, with objectives such as removal of selfsustaining fish populations being achieved in shorter timeframes. 

Cumulative Impacts 

Various unanticipated issues can greatly influence North Cascades Complex 

operations and the funds required to respond to these events. For example, 

extensive flooding in 2004, national security issues, or wildfire can cumulatively 

affect available funds and the way the funds are appropriated. In addition, 

management priorities may need to be shifted to address pressing issues and to 

accommodate reduced funding. The cumulative impact of these unanticipated 

issues would be adverse and long term, but the magnitude of adverse impacts 

cannot be determined because the future is uncertain. 

Conclusion 

Alternative B would have moderate adverse impacts on management and 

operations over the long term, assuming all sources of funding remain fairly 

constant. Total implementation costs would be approximately $2.14 million over 

the next 15 years. Average annual costs for implementation are projected at 

approximately $112,100 for the first three years. As experience is gained 

conducting lake treatment and management, the number of lakes treated 

increases, raising costs to nearly $150,000 per year. Future stocking would be 

funded and implemented by the WDFW. However, should a long-term increase 

in NPS base funding for fishery management become available, implementing 

alternative B would have negligible to minor adverse impacts over the long term. 

Other sources of funding would be sought to reduce impacts on the North 

Cascades Complex operating budget. 

Cumulative adverse impacts on operations could arise from the need to respond 

to future unanticipated events such as flooding, wildfire, or other events. 

However, the magnitude of adverse impacts may range from negligible to major 

depending on the severity of individual future events, which could reduce the 

amount of potential funding available to implement the fishery management plan 

or cause the NPS to shift priorities to respond to more pressing needs. 
E NVIRONMENTAL C ONSEQUENCES

442 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 L AKES M AY H AVE F ISH ) 

Alternative C applies a new adaptive management framework to the 91 lakes in 

the study area, wherein 9 lakes in Ross Lake and Lake Chelan National 

Recreation Areas would have fish and 2 lakes would be evaluated for restocking. 

Of the other 11 lakes in the national recreation areas, 3 would remain fishless, 

3 would have high density reproducing fish removed, and stocking would be 

discontinued in 5 lakes. The remaining 69 lakes (which are in the national park) 

would be returned to their natural fishless condition or would remain fishless. 

Impacts of Proposed Fishery 

Management on North Cascades 

Complex Management and Operations 

Alternative C would place a greater emphasis on fish removal in the national 

park lakes. Costs associated with removing fish in alternative C are shown in 

table 36. These estimates indicate that compared to alternative B, an additional 

$700,000 more funding would be needed to remove reproducing fish populations. 

Management actions that would have an impact on North Cascades Complex 

management and operations would include stocking, fish removal, monitoring, 

evaluation, public outreach, and education. It is assumed that future stocking 

would continue to be funded and implemented by the WDFW and their 

stakeholders with no additional cost to the NPS over the long term. 

Fish removal with gillnets would involve initial start-up costs for durable 

equipment and materials, including gillnets and electrofishing gear (see table 34). 

Most of the costs of gillnetting would involve personnel time because gillnetting 

is a very labor-intensive process. Removing fish with antimycin would be much 

less labor intensive than gillnetting. The cost of piscicide would be the most 

expensive component, particularly for larger lakes. Labor costs would be limited 

to piscicide application and pre- and post-monitoring of native biota. 

As with alternative B, the estimated costs for the first three years of program 

implementation are $336,300 (see table 34), or approximately $112,100 annually. 

Success in fish removal efforts on these initial lakes would be monitored and 

evaluated before the next round of lakes would be chosen for fish removal. Based 

on results, the methods and associated costs would vary from those indicated in 

tables 34 and 36. As experience is gained in lake treatment methods, effort (and 

costs) to remove reproducing fish from mountain lakes would increase to 

approximately $150,000 annually. Costs would increase because removal 

methods would become more difficult and time-consuming to implement, and 

larger volumes of antimycin would be needed for those lakes selected for 

chemical treatment. Given the number of lakes to be treated, evaluated, and 

restocked in alternative C, total costs over the next 15 years would be 

approximately $700,000 more than alternative B, or approximately $2.84 million 

over 15 years (NPS, R. Zipp, pers. comm., 2004). 
E NVIRONMENTAL C ONSEQUENCES

ENVIRONMENTAL IMPACT STATEMENT 443 

TABLE 36: ESTIMATED COSTS OF FISH REMOVAL FOR MANAGEMENT ACTIONS UNDER ALTERNATIVE C 

Note: The lakes highlighted in gray have been identified for the first round of fish removal. 

Lake Name 

NPS 

Lake Code 

Depth 

(feet) 

Area 

(acres) 

Initial Fish Removal 

Method Proposed for 

Alternative C 

Estimated 

Fish Removal 

Costa

Battalion MLY-02-01 16 6.3 Piscicide $94,500 

Bear MC-12-01 152 25.7 Piscicide $70,010 

Berdeen M-08-01 215 126.7 Piscicide $416,521 

Berdeen, Lower M-07-01 36 7.5 Piscicide $13,310 

Berdeen, Upper M-09-01 Unknownb 9.5 Piscicide $16,354 

Blum (Largest/Middle, No. 3) M-11-01 33 12.9 Piscicide $15,622 

Blum (Lower/West, No. 4) LS-07-01 26 6.4 Piscicide $11,771 

Bouck, Lower DD-04-01 63 10.8 Piscicide $19,404 

Dagger MR-04-01 16 8.2 Piscicide $11,248 

Dee Dee, Upper MR-15-01 89 12.2 Gillnet $25,460 

Diobsud No. 1 LS-01-01 11 1 Gillnet $15,000 

Diobsud No. 2, Lower LS-02-01 17 3.1 Gillnet $46,500 

Doubtful CP-01-01 68 30.2 Piscicide $42,496 

Doug's Tarn M-21-01 10 5 Gillnet $75,000 

Firn MP-02-01 38 5.7 Piscicide $8,617 

Green M-04-01 153 80 Piscicide $193,764 

Hanging MC-08-01 33 88.8 Piscicide $55,516 

Hidden SB-01-01 258 61.7 Piscicide $248,391 

Hozomeen HM-02-01 67 97.5 Piscicide $109,008 

Ipsoot LS-06-01 51 8.9 Piscicide $16,040 

Jeanita DD-01-01 8 1.4 Gillnet $15,000 

Kettling MR-05-01 23 9.9 Piscicide $12,681 

McAlester MR-10-01 23 13.2 Piscicide $13,808 

Monogram M-23-01 122 29.1 Piscicide $64,720 

Rainbow MR-14-01 108 15.5 Piscicide $34,159 

Skymo PM-03-01 20 10.8 Piscicide $12,508 

Sourdough PM-12-01 107 27.6 Piscicide $55,855 

Stout EP-09-02 176 25.2 Piscicide $77,863 

Stout, Lower EP-09-01 8 1 Gillnet $15,000 

Thornton, Lower M-20-01 108 55.1 Piscicide $100,209 

Trapper GM-01-01 161 147.2 Piscicide $363,933 

Triplet, Lower SM-02-01 7 2.2 Gillnet $33,000 

Triplet, Upper SM-02-02 12 2.4 Gillnet $36,000 

Wilcox/Lillie, Upper EP-06-01 65 10.5 Spawning habitat exclusion Volunteer labor

Wilcox/Sandie, Lower EP-05-01 20 5.4 Gillnet $10,904 

Total cost of fish removal $2,350,172

Notes: 

a. This table provides a conservative estimate of fish removal costs for alternative B based upon the following assumptions: 

$15,000/acre for gillnetting (NPS, D. Boiano, pers. comm., 2003). Assume one-time use of piscicide antimycin per lake, $450/unit 

of Fintrol® (trade name) at 4 parts per billion, at $45 /acre-foot. Lake volume calculations assume lake basin is cone shaped 

(formula = 0.33 × maximum depth x area). Treatment costs also include salary for four-person field crew ($3,000 for 2 weeks at 

small lake; $4,500 for 3 weeks at medium lake; $6,000 for 4 weeks at large lake) and helicopter transportation of equipment 

(2 flights small lake, 4 flights medium lake, 6 flights large lake). Small lakes 1–5 acres; medium lakes, 6–20 acres; large lakes 

20+ acres. 

b. The depth of this lake is unknown, but for treatment purposes, a depth of 50 feet was assumed in order to calculate the cost of 

antimycin. 
E NVIRONMENTAL C ONSEQUENCES

444 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

As noted in “Methodology and Assumptions,” if the base funding for North 

Cascades Complex remains at current levels, then fishery management actions 

could not be paid for with base funding because it is specifically earmarked for 

base operations. Base funding levels have remained static in recent years while 

costs have increased due to inflation, cost of living increases, and other factors. 

This trend underscores the point that there are few discretionary dollars available 

to fund additional resource management programs such as this fishery 

management plan. Assuming this static trend continues, reliance on soft funding 

from the sources noted previously would be essential for plan implementation. 

The impact of alternative C on park management and operations would be similar 

to the impact of alternative B, with impacts essentially dependent on the amount 

of soft funding received to implement the fishery management plan. Reliance on 

soft funding sources would mean that fishery management actions would be 

implemented in a piecemeal fashion and subject to the unpredictable availability 

of funding for the foreseeable future. At a minimum, resource management 

personnel would routinely have to write funding proposals and secure soft 

funding and develop and maintain partnerships to ensure that steady sources of 

funding and in-kind assistance remained available to implement the fishery 

management plan. Once funding were secured, resource management personnel 

would need to take on the additional burden of training personnel, assisting with 

field work, and providing overall project oversight. Interpretive staff would need 

to assist with public outreach and education to foster public understanding and 

awareness of the program. Under this scenario, the impacts on park management 

and operations would be moderate, adverse, and long term because NPS 

personnel would have to shift workload priorities to accommodate these 

additional tasks, and other ongoing resource management actions may not be 

accomplished. 

Cumulative 

Various unanticipated events can greatly influence park management and 

operations and the funds required to respond to these events. For example, 

extensive flooding in 2004, national security issues, or wildfire can cumulatively 

affect available funds and the way the funds are appropriated. In addition, 

management priorities may need to be shifted to address pressing issues and to 

accommodate reduced funding. The cumulative impact of these unanticipated 

issues would be adverse and long term, but the magnitude of adverse impact, 

however, cannot be determined because the future is uncertain. 

Conclusion 

Alternative C would have similar moderate adverse impacts on management and 

operations as alternative B over the long term. Total implementation costs would 

be approximately $2.84 million over the next 15 years. Average annual costs 

would be similar to alternative B, but the additional lakes targeted for fish 

removal would increase the total cost. Future stocking would be funded and 

implemented by WDFW. Similar to alternative B, if a long-term increase in NPS 

base funding becomes available, adverse impacts would become minor. Other 

sources of funding would be sought to reduce impacts on the North Cascades 

Complex operating budget. 
Management and Operations 

ENVIRONMENTAL IMPACT STATEMENT 445

Cumulative adverse impacts on operations could arise from the need to respond 

to future unanticipated events such as flooding, wildfire, or other events. 

However, the magnitude of adverse impact may range from negligible to major 

depending on the severity of individual future events, which could reduce the 

amount of potential funding available to implement the fishery management plan 

or cause the NPS to shift priorities to respond to more pressing needs. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Under alternative D, none of the 91 lakes would be available for fishing, with the 

possible exception of the 9 lakes identified in table 7 where complete fish 

removal may not be feasible. The “Alternatives” chapter provides a detailed 

description of alternative D. For more information on the 91 lakes, refer to 

tables 5 and 13 in the “Alternatives” chapter and appendix E. 

Impacts of Proposed Fishery 

Management on North Cascades 

Complex Management and Operations 

Alternative D would be very similar in costs to alternative C because the majority 

of costs would be associated with fish-removal treatments at the study area lakes 

(NPS, R. Zipp, pers. comm., 2004). Costs could actually be slightly less than 

alternative C because fishery management actions would be centered exclusively 

on fish removal. There would be no costs associated with stocking, but there 

would be costs associated with monitoring the recovery of native organisms in 

lakes. The cost saving would be difficult to quantify at this point in time given 

the uncertainty of projecting cost savings across a 15-year timeframe. These cost 

savings, however, could be offset by increased law enforcement personnel to 

prevent unsanctioned stocking of lakes. 

Another element that could have a substantial impact on management and 

operation costs is the valuable in-kind role of volunteer contributions to fishery 

management, such as assistance with lake monitoring and fish removal. Given 

the goal of removing all fish from the study area lakes, it is unlikely that WDFW 

or its angling stakeholders would be willing to assist because they would no 

longer have a stake in the outcome. This means that the NPS would bear the sole 

burden of fish removal and lose potentially valuable partnerships and in-kind 

sources of funding and assistance. In light of these various factors, a conservative 

cost estimate for implementing alternative D would be approximately $3 million 

over the next 15 years. 

Although costs would be higher under alternative D compared to alternatives B 

and C, the impact of alternative D on park management and operations would be 

similar to the impacts of alternatives B and C. Impacts would essentially depend 

on the amount of soft funding received to implement the fishery management 

plan. Reliance upon soft funding sources would mean that fishery removal 

actions would be implemented in a piecemeal fashion and subject to the 

unpredictable availability of funding for the foreseeable future. At a minimum, 

resource management personnel would routinely have to write funding proposals 
E NVIRONMENTAL C ONSEQUENCES

446 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

and secure soft funding. Once funding were secured, resource management 

personnel would need to take on the additional burden of training personnel, 

assisting with field work, and providing overall project oversight. Interpretive 

staff would have to assist with public outreach and education to foster public 

understanding and awareness of the program. Under this likely scenario, the 

impacts on park management and operations would be moderate, adverse, and 

long term because NPS staff would have to shift workload priorities to 

accommodate additional tasks, and other ongoing resource management actions 

may not be accomplished. 

Cumulative Impacts 

As with alternatives B and C, various unanticipated events can greatly influence 

park operations and the funds required to respond to these events. For example, 

extensive flooding in 2004, national security issues, or wildfire can cumulatively 

affect available funds and the way the funds are appropriated. In addition, 

management priorities may need to be shifted to address pressing issues and to 

accommodate reduced funding. The cumulative impact of these unanticipated 

events would be adverse and long term, but the magnitude of adverse impact, 

however, cannot be determined because the future is uncertain. 

Conclusion 

Alternative D would have moderate adverse impacts on management and 

operations over the long term, assuming all funding sources remain fairly 

constant. Total cost of implementing alternative D would be approximately 

$3 million over the next 15 years. Average annual costs for fish removal would 

be similar to alternative C. Although there are no average annual costs associated 

with fish stocking, the additional costs of protection required to prevent 

unsanctioned stocking of lakes would increase total implementation costs. Other 

sources of funding would be sought to reduce impacts on the North Cascades 

Complex operating budget. 

Cumulative adverse impacts on operations could arise from the need to respond 

to future unanticipated events such as flooding, wildfire or other events. 

However, the magnitude of adverse impact may range from negligible to major 

depending on the severity of individual future events, which could reduce the 

amount of potential funding available to implement the fishery management plan 

or cause the NPS to shift priorities to respond to more pressing needs. 
ENVIRONMENTAL IMPACT STATEMENT 447

SUSTAINABILITY AND 

LONG-TERM MANAGEMENT 

In accordance with the National Environmental Policy Act (NEPA), and as 

further explained in NPS Director’s Order 12: Conservation Planning, 

Environmental Impact Analysis, and Decision-making, consideration of longterm impacts and the effects of foreclosing future options should pervade any 

NEPA document. According to Director’s Order 12, and as defined by the World 

Commission on Environment and Development, “sustainable development is that 

which meets the needs of the present without compromising the ability of future 

generations to meet their needs.” For each alternative considered in a NEPA 

document, considerations of sustainability must demonstrate the relationship 

between local short-term uses of the environment and the maintenance and 

enhancement of long-term productivity. This relationship is described below for 

each alternative. 

The NPS must consider if the effects of the project alternatives involve tradeoffs 

of the long-term productivity and sustainability of park resources for the 

immediate short-term use of those resources. It must also consider if the effects 

of the alternatives are sustainable over the long term without causing adverse 

environmental effects for future generations (NEPA section 102(c)(iv)). 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A would trade off the short-term use of park resources for long-term 

productivity. Fishing opportunities would continue in the short and long term; 

however, reproducing nonnative fish would remain in some lakes, compromising 

the long- term productivity of native species. In addition, fish would remain in 

naturally fishless lakes over the long term. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

Alternative B would apply adaptive management principles to remove 

reproducing populations of nonnative fish where feasible. Following removal, 

some lakes would be restocked with nonreproducing fish. This action would 

provide some short- and long-term angling opportunities for this and future 

generations. Compared to alternative A, alternative B would help conserve 

biological integrity over the long term because it proposes the removal of fish 

from mountain lakes and either restocking them with nonreproducing fish or 

allowing select lakes to go fishless. As indicated in the impact analyses, with the 

application of scientifically based adaptive management principles, the long-term 

adverse impacts of alternative B on resources in the North Cascades Complex 
E NVIRONMENTAL C ONSEQUENCES

448 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

would range from negligible to moderate. There would be no impairment of park 

resources and values, as defined by NPS Management Policies (NPS 2001a). 

However, in order to be sustainable, continued stocking would require long-term 

management, including monitoring and adaptive management to conserve 

biological integrity. These actions would require periodic commitment of funds 

and personnel for the foreseeable future to ensure protection of park resources. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 N ATIONAL R ECREATION 

A REA L AKES M AY H AVE F ISH ) 

Alternative C would also apply adaptive management principles. Alternative C is 

different from alternatives A and B because it would require removal of fish from 

all naturally fishless mountain lakes in the national park—these lakes would not 

be restocked. Except for some lakes where removal may not be feasible, this 

alternative would deny future generations the ability to fish in mountain lakes in 

the national park portion of the North Cascades Complex. In the national 

recreation areas, self-sustaining (reproducing) fish populations would be 

removed, some select lakes would be restocked, and others would remain 

fishless. Over the short and long term, these actions would reduce angling 

opportunities compared to alternatives A and B. As indicated in the impact 

analyses, with the application of scientifically based adaptive management 

principles, the long-term adverse impacts of alternative C on resources in the 

national recreation areas would range from negligible to moderate. There would 

be no impairment of park resources and values, as defined by NPS Management 

Policies (NPS 2001a). However, in order to be sustainable, continued stocking 

would require long-term management, including monitoring and adaptive 

management to conserve biological integrity. These actions would require 

periodic commitment of funds and personnel for the foreseeable future to ensure 

protection of park resources. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Alternative D proposes the removal of all fish populations, where feasible, in all 

study area lakes in the national park and national recreation areas, and no lakes in 

the study area would be restocked. Compared to alternative A, this would allow 

the conservation of biological integrity in the greatest number of lakes over the 

long term. Fish would be removed using intensive gillnetting in combination with 

electrofishing, cobbling over of spawning habitat, and application of the 

piscicide, antimycin. As indicated in the impact analyses, the long-term impacts 

of fish removal methods would range from negligible to moderate with no 

impairment of park resources, as defined by NPS Management Polices (NPS 

2001a). Until fish were removed, these actions would require monitoring, 

adjustment of management actions, and commitment of funds and personnel over 

the long term to ensure protection of resources in the North Cascades Complex. 

There may be a greater potential for illegal stocking under this alternative, which 

may have short- and long-term impacts on park resources. 
Sustainability and Long-Term Management 

ENVIRONMENTAL IMPACT STATEMENT 449

No lakes would be stocked or restocked (following fish removal) under 

alternative D. From a management standpoint, alternative D would be most 

sustainable because it would eventually eliminate any long-term management 

actions needed to maintain the mountain lakes fishery compared to 

alternatives A, B, and C. However, fishing opportunities in mountain lakes for 

this and future generations would largely be eliminated in the North Cascades 

Complex, except for a few lakes where complete removal of self-sustaining fish 

populations may not be feasible. Anglers would have to fish in lakes outside the 

North Cascade Complex to experience fishing in mountain lakes. 
450 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN

IRREVERSIBLE OR 

IRRETRIEVABLE 

COMMITMENTS 

OF RESOURCES 

The NPS must consider if the effects of the alternatives cannot be changed or are 

permanent (that is, the impacts are irreversible). The NPS must also consider if 

the impacts on park resources would mean that once gone, the resource could not 

be replaced; in other words, the resource could not be restored, replaced, or 

otherwise retrieved (NEPA section 102(c)(v)). 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A would continue to have long-term impacts on park resources, and 

some may be permanent. There would be a permanent presence of nonnative fish 

in naturally fishless mountain lakes. The greatest concern is that reproducing 

populations of nonnative fish would remain in lakes and, in turn, continue to 

have permanent, adverse impacts on native biota. Self-sustaining (reproducing) 

fish populations could completely eliminate some species of native aquatic 

organisms. Once permanently gone from lakes, some of these aquatic species 

may not be restored or replaced; therefore, alternative A has the greatest potential 

to result in irreversible or irretrievable commitments of resources. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

Compared to alternative A, alternative B would reduce the potential for 

irreversible or irretrievable commitments of resources by applying a scientifically 

based adaptive management program to conserve biological integrity while 

maintaining the mountain lakes fishery. Self-sustaining fish populations would be 

removed where feasible. Some lakes would be restocked with nonreproducing 

fish, and others would remain fishless. In lakes where self-sustaining populations 

would be eliminated, the fish would be irretrievably lost. In an estimated 9 lakes 

where complete removal of reproducing populations of fish may not be feasible 

(refer to table 7), there may be irreversible or irretrievable impacts to certain 

sensitive species of native aquatic organisms. At the landscape scale, however, 

populations of these organisms may remain viable in other lakes or habitat where 

fish are not present. Lakes that would remain available for sport fishing would be 

stocked with nonreproducing fish. If monitoring results indicated that biological 

integrity could no longer be conserved, impacts could be stopped, and potentially 

reversed, simply by ending stocking. 
Irreversible or Irretrievable Commitments of Resources 

ENVIRONMENTAL IMPACT STATEMENT 451

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 N ATIONAL R ECREATION 

A REA L AKES M AY H AVE F ISH ) 

Compared to alternatives A and B, alternative C would further reduce the 

potential for irreversible or irretrievable commitments of natural resources. While 

alternative C would apply adaptive management practices to lakes in the national 

recreational areas, the lakes in the national park would be returned to a fishless 

condition by removing all fish populations. Removal of fish populations would 

be irreversible and irretrievable. Nine lakes in the national park (refer to table 7) 

may still contain self-sustaining fish populations over the long term because 

complete removal may not be feasible in those lakes. The irreversible and 

irretrievable commitments of resources in these lakes would be similar to 

alternative B with respect to native aquatic organisms. However, compared to 

alternative B, all study area lakes in the national park portion of the North 

Cascades Complex would remain or become fishless. Sport-fishing opportunities 

would be lost as long as the fishery management plan remained viable and the 

lakes remained fishless. 

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Alternative D would present the least potential for irreversible and irretrievable 

commitments of resources. Nine lakes would still remain in question as to the 

feasibility of complete removal of fish populations; therefore, the potentially 

irreversible ecological impacts of fish in these lakes would be the same as 

alternatives B and C. There would be a permanent, irretrievable loss of fish 

populations, and loss of these populations in conjunction with ceasing to stock 

would eliminate sport-fishing opportunities in the mountain lakes as long as the 

fishery management plan remained viable and the lakes remained fishless. 
452 DRAFT MOUNTAIN LAKES FISHERY MANAGEMENT PLAN 

ADVERSE IMPACTS 

THAT COULD 

NOT BE AVOIDED 

The NPS is required to consider if the alternative actions would result in impacts 

that could not be fully mitigated or avoided (NEPA section 101(c)(ii)). 

A LTERNATIVE A (N O A CTION ): 

E XISTING M ANAGEMENT F RAMEWORK 

OF 91 L AKES (62 L AKES H AVE F ISH ) 

Alternative A would continue to have adverse impacts that could not be mitigated 

or avoided. The greatest concern would be those lakes where self-sustaining 

(reproducing) fish populations remained in naturally fishless lakes in the study 

area. 

A LTERNATIVE B: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (42 L AKES M AY H AVE F ISH ) 

( P REFERRED A LTERNATIVE ) 

Alternative B would also be of concern for the estimated nine lakes where 

complete fish removal may not be feasible (refer to table 7). In addition, the use 

of fish removal methods (including gillnetting, electrofishing, and piscicides) 

may have adverse impacts that could not be avoided using available mitigation 

measures. Although fish removal using the piscicide, antimycin, would be 

closely monitored and mitigated, there may be short-term adverse impacts on 

some native aquatic species. The temporary use of mechanized equipment, such 

as helicopters, and presence of crews would have unavoidable short-term impacts 

on some park visitors. Even with mitigation (such as alerting visitors that lake 

management actions involving equipment may take place), some visitors may be 

adversely affected. 

A LTERNATIVE C: P ROPOSED A DAPTIVE 

M ANAGEMENT OF 91 L AKES UNDER A N EW 

F RAMEWORK (11 N ATIONAL R ECREATION 

A REA L AKES M AY H AVE F ISH ) 

Alternative C would have unavoidable adverse impacts similar to those described 

for alternative B. Nine lakes may still have reproducing populations of fish 

because complete fish removal may not be feasible. Equipment and activities 

would disrupt some visitors, and fish removal methods may have unavoidable 

short-term adverse impacts on some native biota. 
Irreversible or Irretrievable Commitments of Resources 

ENVIRONMENTAL IMPACT STATEMENT 453

A LTERNATIVE D: 

91 L AKES W OULD B E F ISHLESS 

Alternative D would have unavoidable adverse impacts similar to those described 

for alternatives B and C. Nine lakes may still have reproducing fish populations 

because complete fish removal may not be feasible. Equipment and activities 

would disrupt some visitors, and fish removal methods may have unavoidable 

short-term adverse impacts some native biota. For those who believe that fishing 

in the mountain lakes in North Cascades Complex provides an experience that 

cannot be duplicated elsewhere, elimination of the mountain lakes fishery would 

have an unavoidable impact on their recreation experience.