A REVIEW OF THE “GRAND CANYON 

NON-NATIVE FISH CONTROL PLAN I: 

SHORT TERM MONITORING AND RESEARCH ACTIONS” 

BY 

GCD AMP SCIENCE ADVISORS 

JILL BARON 

LANCE GUNDERSON 

JAMES KITCHELL 

DALE ROBERTSON 

HAROLD TYUS 

ELLEN WOHL 

L.D. GARRETT, EXECUTIVE COORDINATOR 

JANUARY 2009 
EXECUTIVE SUMMARY 

A REVIEW OF THE “GRAND CANYON NON-NATIVE FISH CONTROL 

PLAN I: SHORT TERM MONITORING AND RESEARCH ACTIONS” 

GCDAMP SCIENCE ADVISORS 

 This Science Advisor review surfaces several issues and concerns with the 

proposed Non-Native Fish Control Plan. It also cites several important contributions of 

the plan. We understand the authors desire to emphasize research and monitoring 

approaches in this plan due to existing uncertainties. However, this could have been 

accomplished while placing the primary focus on non-native fish control activities. 

 Following an adopted procedure used in most of our reviews, we have provided 

general comments, specific comments and recommendations for revision of plan. This 

executive summary overviews our general comments and recommendations. 

General Comments 

Although much of the information necessary for an effective control plan exists in 

the document, it does not have appropriate context, organization and balance. Of 

particular importance is the omission of a general strategy for this program of work that 

speaks to its overall goal, processes for determining the key problems to address, areas of 

priority focus, balance of management and science required, integration with other 

ongoing programs, etc. As noted above and proposed by the authors, it is drafted more as 

a research and monitoring plan, rather than a Non-Native Fish Control Plan supported by 

research and monitoring activities. 

 The issue of length of the planning cycle to produce a short term and long term 

control plan is a concern. Although predation surfaced as a perceived critical threat in the 

2002-2004 period, the GCMRC response for a final control plan seems to extend from 

2004-2010, with a short term plan in 2009. 

 The proposed schedule and steps in the current planning process could benefit 

from redesign. The SAs accept the fact that the short term plan may better inform the 

long term plan to be completed in 2010. However, we feel the gains will be marginal 

with the limited funds proposed for science activity, especially field science. We propose 

GCMRC consider an alternative approach, wherein a single Fish Control Plan would be 

completed in 2009 with short term and long term management and science elements. We 

2
feel this approach may better support the FY 2009-2012 management and science 

direction of the GCDAMP. 

 The authors provide good treatment of issues, methods and relative success in 

controlling non-native cold water fishes. This is demonstrated in sections on Rainbow 

Trout and Brown Trout. The text presents significant less certainty with respect to 

control of non-native warm water fishes, reflecting appropriately the knowledge in this 

system. 

 The plan provides reference to other ongoing GCDAMP management and science 

fish biology programs, but the text is insufficient in clarifying the linkages and 

integration that should occur across these programs to best benefit non-native fish control 

now or in the future. To be effective, integration of management and science programs 

should be articulated in both the overall strategy as well as individual non-native program 

elements presented. 

 The plan lacks specific discussion of resource needs, especially budget needs. 

Information is necessary for transition of science application to management control 

actions, who is likely to complete control actions, external budget needs, and all 

contingency and anticipated new GCMRC research and monitoring needs. 

 Inclusion of the contingency plan is an important element of the document. The 

SAs agree with GCMRC in its review request that this element needs more development. 

The approach needs leadership of management agencies and tribes to craft appropriate 

public relations, rapid response control, triage, and monitoring assessments. 

Recommendations 

 Several general recommendations are proposed from this review. The control 

plan should be revised to respond to general concerns raised in the review as follows: 

• Presentation of an overall management and science strategy is necessary to 

effectively integrate this program into the overall set of adaptive management 

activities of the GCDAMP and associated agencies and tribes. 

• The plan needs to better relate the collaborative effort of managers and 

scientists who developed the plan, i.e., managers and scientists from TWG 

and GCMRC, including authorship. 

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• The length of the overall planning process to develop short and long term 

plans needs to be reevaluated and shortened as possible. 

• The plan needs to be revised with the objective to have non-native 

management control actions as the primary focus of the plan and monitoring 

and research as support activities to insure best control approaches are 

implemented. 

• The plan should more clearly articulate linkages and integration of proposed 

management and science actions to related activities occurring in other GCD 

AMP and agency affiliated programs, especially these related to fish biology, 

fish control, i.e. food base, near shore ecology, translocation, etc. 

• GCMRC and TWG should reevaluate their proposed two plan approach. An 

alternative would be to develop one plan in 2009 that incorporates short and 

long term management and science elements for the period 2009-2012. It 

would of necessity have to have a strong monitoring program with supporting 

science in the initial four years, is 2009-2012. Most of the information 

necessary to revise this plan exists either in the plan or referenced documents. 

• We concur with GCMRC that a pilot experiment of various control and 

monitoring approaches for catfish should be pursued. Carp should be added 

to the pilot. Both are proven effective warm water predation fish. 

• GCMRC and TWG should articulate the projected management and science 

resource and budget needs over a decade period. 

• The contingency plan needs to be better developed with significant leadership 

of TWG resource management agencies. 

 

4
A REVIEW OF THE “GRAND CANYON 

NON-NATIVE FISH CONTROL PLAN I: 

SHORT TERM MONITORING AND RESEARCH ACTIONS” 

GCD AMP SCIENCE ADVISORS 

INTRODUCTION 

 The Science Advisors conducted this review from the perspective that it 

represents a part of the overall biological management and science program of the GCD 

AMP. That is, GCDAMP, Tribal and federal and state government agency biology 

programs are now individually and collectively addressing many parts of the interacting 

factors affecting native fish, i.e. competition, habitat, food base, predation, pathogens, 

etc. In previous reviews of some of these management and science programs the SAs 

have stressed that the programs (both individually and collectively) need to express more 

integration in science and management questions addressed, stated objectives, hypothesis, 

research design, management activities, etc. 

 The SAs have referenced in past reviews areas of science and management where 

integration is occurring and where it is not occurring. This review follows this 

established approach by the SAs. It most often addresses general issues, and references 

activities by both managers and scientists that need to express more integration. 

REVIEW PROCEDURES 

 The SAs both understand and appreciate the proposal by GCMRC to first develop 

a short term plan to develop more knowledge and management experience, and then a 

longer term plan to apply this increased knowledge. However, concern exists over a 

planning process that is proposed to extend over 6 years; i.e., 2004-2010. We 

recommend procedures to shorten the process. 

 The SAs addressed this review with the understanding that a comprehensive nonnative fish control plan was desired by the AMWG in their October, 2004 request to 

GCMRC as follows: “Consensus Item: Authorize funds for workshops, and direct 

GCMRC to further develop warm water species plan with TWG. The workshops include 

GCMRC workshop as described in the prospectus for warm water species research and 

participation in the Upper Basin Recovery Implementation Plan workshop on non-native 

5
fish control”. The Non-Native Fish Ad Hoc Group and GCMRC have characterized this 

activity as development of a Non-Native Fish Control Plan. 

As such, in this review the SAs looked for balance in treatment of both management 

control and science direction. 

 The SAs also continue to look for specified approaches to improved management 

and science integration, while realizing GCMRC needs to implement its programs under 

separate RFPs, cooperative agreements, etc, which challenge a predefined integrated 

approach. Yet, there are explicit interrelationships of habitat, food base, competition, 

predation, pathogens, etc. in biology programs that can best be approached through 

integrated science and management programs. 

 As in past reviews, the SAs provide in this report both general review comments 

and specific review comments, followed by recommendations. An Executive Summary 

is also provided to capture the salient findings of the review. 

GENERAL REVIEW COMMENTS 

Overall Strategy 

 The document does not effectively present an overall strategic procedure for 

approaching this problem, excepting that it will step through a two-tier planning process, 

i.e. short term/long term plan. An overall “control plan strategy” is missing. Lists of 

activities are provided that could be pursued, but an actual control plan is not developed. 

It does develop some tactical and operational elements quite well, but they should 

proceed from and clearly support the overall strategy. We are not suggesting that a 

strategic plan be written, but early on in the control plan a strategy should be presented. 

Some elements to consider for this section follow. 

• Specification of the overall problem or problems by GCMRC and TWG. 

What is to be accomplished by scientists, and managers, both in collaboration 

and, individually. What native (s) are most threatened, what age classes, 

where? What non-natives are the greatest threat, where? 

• Specification of general management control approaches. What approaches 

are proposed by what groups and over what time periods? What pilots are 

proposed? 

6
• Prioritization of competing options needs to occur based on some objective 

criteria. 

• Specification of general science and monitoring needs. What programs are 

necessary, probable lengths, necessary integration? 

 Without an overall strategy the reviewer can not effectively evaluate the lists of 

potential approaches. These assessments should have been accomplished by the authors. 

Further, the organization and content of many parts of the report fails to convey a logical 

plan of needed actions, be they management control or science activities. 

Length of Planning Process 

 Concern exists over the length of the planning process. In 2001/2002 GCMRC 

expressed in their proposed long term experimental approaches a need for increased 

predation assessments and potential controls. Fish biologists, the SAs and AMWG has 

expressed the need to understand and control predation, especially from cold water 

pacifivores such as rainbow and brown trout. 

 The 2002/2003 assessments of declines in the HBC adult population heightened 

concerns over predation and as noted in the plan resulted in the Non-Native Fish Ad Hoc 

Group. This was followed by AMWG’s formation of the Humpback Chub 

Comprehensive Plan Ad Hoc Group to respond to the presumed highly threatened HBC 

population. 

 When GCMRC was asked in 2004 to develop the control plan collaboratively 

with TWG it would seem to have an attached urgency. As such, concern exists over the 

seemly extended period to develop the control plan. A two year development period 

would have seemed more reasonable. 

 We understand GCMRC proposes to complete a control plan in 2010, using the 

intervening space, i.e. 2004-2010, to develop improved knowledge outlined in the 

proposed short term plan. The SAs encourage GCMRC to reevaluate this two step 

procedure for the following reasons. 

1. A control plan completed in 2009 with more definitive control related actions 

(management supported by science) would be helpful to inform fiscal year 

2010/2011 planning. 

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2. Releasing a plan in 2009 and updating the plan in 2012 would bring this effort 

more in line with other GCDAMP management and science planning. 

Balance of Management Control and Science Activities 

It is presumed AMWG directed a collaborative GCMRC/TWG approach to 

incorporate all ongoing and planned activities of both managers and scientists regarding 

non-native fishes, and selected native fishes. Yet, there is limited specification of 

management controls and discussion of the collaborative efforts with TWG and resource 

managers to define the needed controls. We are aware that managers and scientists are 

collaborating in the Non-Native Fish Ad Hoc Group and important recommendations and 

planning are formulated in the group. Also, very critical non-native control activities 

proposed by the Humpback Chub Comprehensive Plan Ad Hoc Group are considered in 

these discussions. However, these management/scientist discussions are not documented 

as potential management controls for implementation. Management planning and 

management controls are not made an explicit part of the plan in balance with science 

proposals. 

 As a non-native fish control plan, this document appears improperly specified. It 

is understood that AMWG’s direction to GCMRC in 2004 was to develop a Non-native 

Fish Control Plan so that existing and/or potential future impacts of predation to 

Humpback Chub Populations could be mitigated. As written, this document does not 

present adequate focus on proposals for management control activities. 

 Any control plan, short or long term must focus on management control actions. 

Monitoring and research is critical as regards how it effectively supports the control 

approaches. In the plan it is necessary to specify what management and science actions 

are needed to eliminate, reduce, or mitigate defined problems. These could be defined 

for both the short term and long term. All actions identified need to be placed in some 

sort of priority system by both managers and scientists. In this case, it may help to ask "if 

and only if" questions. And all necessary short and long term research and monitoring to 

support the program must be specified. These objective processes may have been 

followed, but it is not documented well in the text. 

Identifying Potential Impactors and Referencing Other Programs 

8
 Anticipating all potential impactors and surprises is important in developing 

control plans. This issue is raised and addressed, but could be refined. There is a very 

great danger of ignoring potential adverse future effects that may be caused by nonnative 

predator fishes that are not very abundant now. In this document Table 1 lists 

"dominant" nonnative predator fish by reach. Thirteen potential nonnative predator fish 

have been identified in the CRE, but all are not addressed here. Only 7 are presented in 

Appendix A. Projected future changes in water temperatures or flows in Grand Canyon 

might allow one or several of these other non-natives to proliferate rapidly. 

 The key in this assessment is to begin to focus on what would be considered to be 

your predator fish of highest risk and habitats of highest risk. Of these what fish and 

habitat areas create highest threat to HBC? We assume this objective process was 

followed to identify catfish as a target species. We do not disagree with a focus on 

catfish, and in fact would suggest carp also be considered in a pilot control activity. 

 It also seems there is limited concern that some new fish from the LCR or other 

source might also become a problem, since they are not fully addressed. Perhaps these 

risks can be minimized in the short term, but they should not be excluded. In discussions 

of long term needs these threats certainly should be identified and the risks evaluated. 

Since no risk assessment is cited we presume it is in planning. An assessment needs to be 

referenced or completed. The SAs recommend the document be revised to address the 

above concerns. 

 This document could be strengthened by acknowledging nonnative fish control 

problems and control efforts in the upper basin, where fish control has progressed from 

strategic planning to site specific actions. It would help the rewrite of this document to 

evaluate a process that has already occurred in the basin with the same fish species. 

 The first strategy in the upper basin was to identify the major nonnative fish 

issues and problems, and then consider management controls, science strategies, potential 

problems and conflicts in each area, and resolution in each instance. Also, all known and 

potential non-native predator fishes were evaluated for how they might threaten the 

existence of each native fish, to identify high priority areas for implementing control 

areas, etc (Tyus and Saunders, 1996). 

9
 The authors might also benefit from interactions with authors who have 

conducted at least informal risk assessments of some of these species i.e., Valdez and 

Speas (2007). We do feel the paper does a good job of reviewing ongoing cold water 

fish control initiatives, although the purpose, need, and effectiveness of these projects and 

how they specifically support short term control of the non-native fish is not always clear. 

 The reality of this program effort is adaptive management, i.e. test, evaluate, 

revise and test again. Focus on the warm water predator of greatest threat. Also, focus 

early tests in areas where warmer water is more available. Use coarse grained evidence 

from distribution change, presence/absence and juvenile trends as guides. 

Use of a Two Plan Process 

 The authors propose that the justification for having this short term plan is to 

obtain more information through monitoring and research to more clearly establish 

improved control efforts for the 2010 Long Term Control Plan. However, many areas of 

uncertainty are presented that have profound effect on understanding non-native fish 

impacts, including gear effectiveness, sampling effectiveness, remote sensing 

effectiveness, defining non-native/native interactions, etc. Only limited field science 

activities are proposed to gain these resolves in 2009. Due to their complexity and 

proposed science activity, it would seem that they would have only limited resolve even 

by 2012. 

 The SAs encourage GCMRC to consider an alternative approach. Revise this 

document and submit it now as the final control plan, listing appropriate pilot 

management control actions and science needs for the periods 2009-2012. Propose a 

significant revision of the plan in 2012. It would seem three to five years of learning in 

the areas identified will be needed to significantly advance new non-native fish control 

measures. 

Program Integration 

Issues of program integration arise in two areas in this plan. The plan should 

specify an agreed upon priority list of non-native fish management controls or pilot 

programs control for the next 5-10 years. These selections should reflect an integrated 

management and science assessment of options, associated risks, knowledge, costs, etc. 

10
We cannot determine if these assessments by the GCMRC and TWG occurred, because 

no priority lists of control actions are proposed. 

 Currently non-native fish control or pilot actions are occurring in the mainstem 

and tributaries, i.e. mainstem RBT control, tributary BT control, mainstems warm water 

species pilot control, etc. One cannot determine from information presented if these 

actions are resulting from integrated planning. Further, research and monitoring 

activities by GCMRC, NPS, ADF&G, etc. related to support of non-native fish control 

are occurring on habitat, food base, predation, competition, etc, but it is not clear how it 

is all integrated. Some concept of GCMRC‘s integration of fish biology science is 

presented but it lacks clarification of intent. 

Schedule, Resource Needs and Budgets 

The control plan does not clarify anticipated resource requirements for the 

proposed program. A separate section on resource needs including budgets is necessary 

for appropriate evaluation of the plan. 

 The presented short term plan is proposed to fit into a long term plan, but it fails 

to provide any schedule of actions for the transition. The plan of actions should clarify 

what is to be accomplished next year and the year after. The schedule was not presented. 

 Resource requirements to launch a control plan could require significant new 

expenditures by state game and fish agencies, federal resource management agencies and 

tribes. As such, their leadership, potentially through the TWG, Non-Native Fish Ad Hoc 

Group or other entity is needed to define actions and associated costs. These evaluations 

may have occurred, but they are not presented in the plan. Also, potential expenditures to 

respond to additional research and monitoring needs are mentioned, but actual projected 

costs for those programs are not provided. 

 Lacking even first estimates of budget requirements it is difficult to contrast and 

compare various management control needs and science needs for this program. A table 

of ranges of potential costs for alternative programs over a five or 10 year planning 

horizon would be useful. 

Contingency Plan 

 Evidence does exist that threats from exotic fish to native fish can materialize 

quickly and overwhelm the ability of management agencies to respond in a timely 

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manner. As such, incorporation of contingency planning in this document is critical. 

However, drafting of this section seems to lack critical leadership of management 

agencies serving on the TWG. Further, it could be significantly improved by 

development of or referencing an appropriate risk assessment of non-native fish and 

native fish interactions in the CRE and its main tributaries. 

SPECIFIC COMMENTS 

This section identifies review comments, concerns, and suggestions by the science 

advisors on specific sections of the plan. The final section of the review will present 

recommendations that respond to general and specific comments. 

P1, P1, S2 

 There needs to be a paragraph in the executive summary and a page in the text 

that addresses the AMWG strategic approach to the issue of Non-Native Fish Control. In 

past GCD AMP programs habitat manipulation has also been a primary factor used to 

control non-natives; i.e. flows, temperature, sediment etc. Further, other management 

policy experiments and even management actions have also occurred. Concern exists 

that this plan is oriented primarily to science, whereas its focus should be on obtaining 

desired resource response, i.e. non-native control. The 2004 charge from AMWG to 

GCMRC as presented in the plan (p6, p2, s1) was to “develop a management plan to 

control non-native fish populations and reduce the populations negative effects on native 

fish in Grand Canyon.” The emphasis of this plan then needs to be management control 

methods for non-native fish. 

P1, P2, S3 

 This plan should be focused on two clear outcomes, defining best available 

current controls supported by management science and defining new science needs and 

new management policy tests to improve control capability. 

 The Executive Summary and Plan needs to begin with overall strategic statements 

of the problem and useful management and science approaches to non-native control that 

captures competition/predation/habitat relationships in a space/time format. Focus should 

exist on mitigating impact to native fish (HBC) species with science based management 

approaches. Since the LCR native fish population is the most critical group for 

protection, it would seem to have primary focus in the plan. 

P3, P1, S2 

 The entire approach should be system based with a focus on identifying primary 

non-native fish and habitat locations of concern. This statement seems to focus on the 

concept that non-native fish introductions during and after the dam construction period 

are the primary source of today’s populations. Is that true? Historically introductions 

began prior to the 1900s and some became established, i.e. several before the dam 

closure. Some have had long term impact, i.e. carp. 

12
P3, P2, S4 

 This plan should identify the immediate management actions that are being 

applied and can be applied in all major areas of native fish threats in the near term. We 

agree that this plan needs to have appropriate focus on monitoring and research, 

especially to identify best control measures. However, if it is a control plan, its primary 

thrust should be to evaluate GCD AMP implemented and proposed management actions 

and policy assessments and provide some assessment of their potential short and long 

term contributions to non-native fish control. We agree that short term monitoring and 

research actions help define most effective short and long term non-native fish control 

methods. However, in balance the focus of any control plan has to be management 

actions, pilot control projects, policy experiments, and management assessments etc that 

are currently and will be the on-going basis for non-native fish control. 

P 3-6 

 Although pages 3-6 have weaknesses as defined above, they do provide some 

tracking from GCD AMP issues, goals, objectives, information needs and strategic 

science questions through AMWG planning and direction (i.e. Non-Native fish Ad Hoc 

Group) through a discussion of science and management, studies, assessments, actions 

etc. However there is limited focus on defining explicit control methods for use and 

evaluation during the period 2008-2012. 

 Concern exist that work by the HBCCP Committee that receives minimum 

attention in defining areas of non-native control. Their contributions are mentioned 

briefly later in the text but not nearly at the prominence related to their contributions. 

 Control approaches to the trout species are pretty well known permitting 

specification of these as proposed control actions. Proposed controls for warm water fish 

are less certain but could be proposed as pilot policy experiments. The focus should be 

on predators of greatest threat. Catfish and carp are good candidates. 

6-11 Bullets 

 These specific examples are declarative in specifying GCMRC/AMWG/TWG 

responses to the needs specified by the Non-Native Fish Ad Hoc Committee. Many of 

the examples are also overall AMP (GCMRC/AMWG/TWG/SAs) responses to the HBC 

Comprehensive Plan (HBCCP). 

 A concern exists that this plan does not provide a summary or brief assessment of 

several of these accomplishments, i.e. channel catfish monitoring and control, removal 

methods testing in Shimino Creek and LCR, tests of fish tracking technology, etc. 

P7 Scientific Assumptions 

 The lists of assumptions are certainly appropriate. Did the contributing scientists 

consider the following assumption? 

 “The impacts of non-native fish predation/competition on native fish can be more 

significant when interacting with other potential life cycle effectors, i.e. flow regimes, 

water quality, pathogens, etc.” 

P9, P2 

13
 The issues of gear effectiveness and sampling designs are factors that will 

dominate the potential effectiveness of the fish control program. As you state in P9, P3, 

“The ability to capture non-native species and detect changes in their populations and 

distribution is vital to directing non-native control. Predictable catchability of exotics is 

required to provide any reliable assessment of their impacts on native fish in this system. 

Yet, catch gear performance is largely unknown making assessment of sampling designs 

difficult. Brief references are made to unpublished data from several years since 2002 

that address this issue. Yet, none of these data or summaries are presented. At the recent 

GCMRC Conference the San Juan RIP representative referenced success with catfish 

removal in that system. Yet, an assessment of success in the San Juan is not referenced 

in this plan. Since this issue is so basic to control success a more complete knowledge 

assessment (science and management literature) would seem relevant here. 

P11, P2, S2 

 It is unclear what a “Boot strapped CV” defines. Also, in this paragraph you 

reference (P11, P2,S5) “extensive sampling”. Do you mean “intensive sampling”? In 

P12, P1 and 2 the discussion of use of electro fishing for brown trout is not clear. It 

characterizes electro fishing as the most “viable option” for these species but then 

characterizes it as difficult to capture the species, making the method “logistically 

infeasible”. In these sections you also reference that electro fishing may be adequate for 

smallmouth bass and walleye because of their vulnerability to the method, citing 

unpublished AG&F data. But later you state that capture probability for the two species 

are unknown. You also reference that boat electro fishing is not adequate for small 

bodied fish, but in P12, P4 you cite Korman’s and others (2006) work with boat electro 

fishing (slow shocking) as being effective on young and therefore assumed small body 

fish. 

 It is obvious that there is significant uncertainly regarding gear effectiveness. 

You note this early on. However, given that fact, discussions as noted above can be 

confusing. When you cite a particular method as being “viable” one might conclude that 

it is fully evaluated and known to be “effective”, given whatever criteria being used to 

determine effectiveness. 

P16, P2 and 3 Seining 

 The general statements regarding application of this method to back waters 

provide some insight into the protocols, but it lacks clarity. 

 It is stated that one pass is made and captures are reported per area seined. Large 

and small backwaters seemed to be treated differently. Is there a specific protocol 

developed from capture assessments? 

P16, P4 Channel Catfish 

 Catfish is a most difficult species to control given all methods applied. Stink baits 

have enhanced captures in net and hook and line applications in many regions. It would 

be expected to improve catches in the CRE. You cite seining to be effective and electro 

fishing not to be effective but no specific assessment data is provided. Again, at the 

recent GCMRC conference the San Juan Group reported effectiveness on catfish 

removed. What methods are they using? 

14
P17, P2, Table 3 

 No effectiveness assessments are provided for hoop net sampling in the LCR, 

except to note it is ineffective on catfish relative to angling. Do data exist to develop 

assessments of capture effectiveness? 

P18 

 The discussion of the Bright Angel Creek brown trout removal programs appears 

to be supported by more analytic assessments. However, throughout the sections on 

methods different descriptions of effectiveness are used, i.e. capture probabilities, 

removal effectiveness, abundance measure, distribution, coefficient of variation, relative 

abundance, etc. Some have been explained, i.e. coefficient of variation and capture 

probability. Others have not. Explanations of effectiveness measures would be helpful. 

 The qualities of the assessments that have been completed present a measure of 

control effectiveness similar to the mainstem RBT control program of 2002-2006. In 

both cases it is apparent that even with an aggressive control plan continued production 

of adult spawning RBT an BT is occurring. This BT control program assessment in 

Bright Angel Creek and the mainstem RBT assessments seem to point to the need for 

continued control programs for those two predators while evaluating methods for 

improved control effectiveness to reduce program costs. 

P19, P1 & 2; Shimano Creek 

 Whereas the presentation on Bright Angel Creek provides assessments of methods 

and control plan effectiveness, this section refers the reader to the NPS for data 

assessments. The data needs to be provided by GCMRC in this plan, as well the findings 

on displaced RBT from clear creek in the 2005 high flows. Evaluation of methods 

effectiveness and flood displacements in tributaries is important to the overall control 

plan. As such, this assessment should be made more complete with NPS data. 

P19, P3, Sonic Telemetry 

 As in other, sections with other methods, the assessment of this methodology 

presents both promise and significant problems. Of greatest concern is that assessments 

were conducted and cited but no data is provided to evaluate effectiveness. At least 

summary statements on data and assessments need to be included. 

P19, Recommendations 

 The recommendations reference the annual “Non-native Fish Workshops” as a 

place where priority control efforts will be determined by fish scientists. Clearly scientist 

evaluation of what are the most scientifically appropriate control and science approaches 

is critical input to implementation of a management control plan. However, effective 

setting of priorities and plan implementation must of necessity contend with many nonscience issues of law, policy, budget, agency authorities and responsibilities, etc. As 

noted earlier, this document should be proposed as a management control plan 

underpinned by all available science understanding. This document treats very lightly the 

primary role of managers in the control plan. 

 

15
 To the issue referenced above, i.e. setting priorities on control approaches; it 

would appear that would be the role of managers. And would address much more criteria 

than listed at the end of paragraph 1 on page 20. 

 Following are comments on your management and science recommendations. 

1. In your studies of natal origins using otoliths, isotopes, and larval drift 

samples for native and nonnative species, advantage of sampling being done 

by the Nearshore Ecology Project. Every fish collected by them provides a 

sample point. Non-natives are likely to be less abundant so each caught is 

useful. That helps define the history of habitat overlap. In addition, their 

catches tell you about community composition and habitat overlap through 

time and space. 

2. For your study to identify sources of juvenile and adult nonnative fish such as 

tributary inflows, dam passage, and illegal stocking, you might want to delay 

this in accord with contingency planning for control projects. 

3. Your large-scale sonic telemetry study is of moderate priority. It’s costly and 

takes lots of time for the data return. Launch a pilot study first. 

4. Laboratory flume experiments to investigate mechanisms by which nonnative 

fish negatively affect juvenile humpback chub might provide some insight. 

Unfortunately flume studies tell you what fish do in flumes. This should be 

lower priority. 

5. Catfish capture and monitoring studies using catfish hoop nets and stink 

cheese bait should produce results. Although much trial and error is involved. 

Pursue immediately. Focus on the LCR and its proximate mainstem. This 

looks like a candidate for Control projects. We would suggest you also try 

other baits and techniques known to catch carp. 

6. Your small-bodied nonnative fish and YOY capture and monitoring study 

using slow-shocking techniques (nearshore ecology) could have promise 

 Again, coordinate and collaborate with NSE research and research at/above 

Lee’s Ferry. In the simplest case, have them provide non-natives they catch 

and/or the data on catch rates. Presence/absence is your first source of insight. 

7 The project to increase sampling intensity around Lees Ferry to attempt 

increased detection of newly invading nonnative fish species is a good idea. 

It’s easier, less expensive and can be done more frequently than river trips. 

8. The LCR project for continued pilot testing of catfish and carp capture 

methods in the Little Colorado River should be a high priority pilot control 

measure and could be considered a mini-policy experiment. It could become 

a control method that works. 

P19, P5: 

 The work by Valdez and Spears (2007) (non-native fish assessments) is 

mentioned as the most advanced work on the subject. Yet, a summary of its findings is 

not presented to which readers can contrast the recommendations in this plan. 

Pages 20-24: Monitoring and Research 

16
 In paragraph 1, page 20 the authors cite that this document “focuses on improving 

monitoring and research, core components of efficient removal systems”. We do not 

disagree that this should be an important element of the plan, but it exists to support 

selection of appropriate control methods, and they should be the primary focus of the 

plan. 

 The following table provides comments on the proposed recommendations on 

Monitoring and Research 

Table 1: Comments on Recommended Monitoring and Research 

Recommended Science Area SA Comment 

• Spring Area Identification Agree to its importance 

• Source Identification Agree, especially as relates to tributaries 

• Fish Sonic Telemetry Agree, and should be part of remote 

sensing program 

• Remote Pit Tag Detectors Agree, Should be part of new remote 

sensing program. Greater specification of 

this study would be important to 

understanding its value. Most important 

are environmental condition determination. 

• Channel Catfish Agree and propose carp also. 

• Small Bodied & YOY Could this study be better addressed in a 

test stream environment? 

• Lees Ferry This is considered the least favorable CRE 

segment for warm water non-natives. 

Would segments of the lower river be 

better? 

• Mechanical Removal LCR A question relates to the statement; 

“warmer water is highly correlated with___ 

decreased non-native abundance! Is this a 

known validated finding or an anomaly 

associated with mechanical removal? 

Agree that RBT should be maintained at 

low level, i.e. 10-20% of 2003 levels. 

P 24; Chemical Renovation and Barrier Construction 

 These proposed management procedures, although seemingly not feasible for the 

CRE or LCR, could afford management and science restoration opportunity for 

tributaries such as Bright Angel, Shimino, Clear Creek, etc. 

P 25; LCR 

 The critical importance of the LCR to HBC restoration in the CRE would warrant 

an aggressive program of Non-native removals from the LCR if no monitored impacts 

occur to HBC. 

P 26; Bright Angel Creek; Shimino Creek 

17
 Brown trout is one of the most effective predators of HBC in the CRE. The SAs 

agree that aggressive control and monitoring assessment should be continued in Bright 

Angel and Shimino Creek. 

P 265; Reporting Procedures 

 Noteworthy in this document are references to other agencies for data and 

assessments that should be included in this document. The SAs agree that all 

assessments should be available to the AMP in a timely manner. 

P27; Annual Non-native Fish Workshop 

 The SAs concur that this would be a critical element to advancing the Non-native 

fish control plan. It is noted that it should include cooperators and topic experts. Other 

text references imply a strictly science based workshop and participants. Because the 

proposed program requires involvement and direction of managers, the workshop(s) 

should involve management oriented programs and managers, especially those having 

mandated authorities in fisheries and fisheries habitat management. 

P 27; Prevention and Public Outreach 

 As noted these are critical elements of resource management programs in very 

public places such as Grand Canyon. Although having the GCD AMP public outreach 

AHG perform some of these activities has merit, i.e. draft and print information 

pamphlets. These efforts are more effectively handled by NPS, USBOR and USGS who 

have professional staff. Perhaps the POAHG could be utilized to participate in planning 

activities of the critical state and federal agencies. 

P28; Contingency Planning 

 It would appear at first reading that the contingency planning is incorporated to 

address required interagency management actions for non-native fish control. It reads as 

though one would not take any management actions unless identified interagency 

thresholds were exceeded. The discussions in the contingency planning section would 

benefit from findings of the work by Valdez and Speas (2007) referenced earlier. 

 Triggers regarding associated expansion of different species might be effective 

where species assessments exist. Over the next 10 years these might be viable for some 

species as data and assessments are improved. Changes in distribution, species 

composition and length composition (ages) were discussed earlier in the plan, not 

necessarily as trigger elements of a control plan, but in similar context to the points made 

in the contingency planning sections. 

 Targeted flow manipulation to control non-natives, as other contingency 

recommendations, appears to be proposed to react to an identified rapid expansion by an 

exotic. They would occur only when comprehensive knowledge of native and non-native 

life history exist, data that is limited to the CRE. 

 

P30; Contingency Planning Fund 

 A Non-Native Fish Control Fund is certainly critical to insure science support for 

long term success of this proposed plan. Otherwise, as noted, science funding could be 

directed inappropriately to management activities. This issue has been raised in several 

18
SA reviews and in TWG and AMWG discussions, but never discussed with the objective 

of defining a potential solution, i.e., when is an action a “management action” and how is 

it to be funded. These discussions have surfaced when attempting to address 

management actions, Recovery Implementation Programs (RIP), desired future resource 

conditions, and the long term experimental plan. 

 Due to the extensive uncertainties associated with non-natives it would appear 

that a contingency plan should address only the event or events of highest probability and 

greatest impact. Use of the Valdez and Speas assessment might assist in the approach. 

RECOMMENDATIONS 

 A strategy needs to be developed for this program and appear as the first section 

of the plan and the first paragraph of the executive summary. Several aspects of the 

strategy are important to clarify; exactly why the program is needed; who will implement 

the program; what are the specific issues to be addressed; what are the primary 

procedures (i.e., management controls, science) proposed and who will conduct them; 

how will it be funded, etc. For example it is assumed this is a collaborative program of 

GCMRC and TWG, but TWG input seems minimal. A Non-Native Fish Control Plan 

implies management control actions as the primary focus, but it is not the focus of this 

plan. The strategy can clarify this approach. The strategy can be developed in three to 

four paragraphs, and is necessary to inform other sections of the plan. 

 We recommend that the proposed second phase of this planning process for 

drafting a long term plan be revised. GCMRC should instead consider revising this plan 

to a final plan in FY 2009 that will cover the period 2009-2012. Potential approaches to 

respond to this recommendation exist in the following recommendations. 

 The focus of this plan needs to be changed to management actions for Non-Native 

Fish Control. Research and monitoring programs necessary to better inform these 

management activities in the short and long term are critical elements of the plan, but 

should be designed to support proposed management control activities. 

 The primary justification to draft two plans i.e. short and long term appears to 

relate to significant uncertainties and the need to conduct monitoring and research to 

better inform a “long term” plan. We agree uncertainties exist and better science will 

improve control actions. However, this selected approach creates an extended window 

where assumed critically needed focus on non-native fish control methods and tradeoffs 

are not being deliberated, an important element of adaptive management. 

19
 Revising this plan to focus on non-native fish management control actions and 

research and monitoring programs for 2009-2012 could accomplish most objectives 

prescribed for the currently planned short and long term plans. It could also permit focus 

by managers on implementation of control actions pilot control projects, needed science 

support over a longer term, required cooperation by resource management agencies and 

decisions on agency budgeting of these control measures. 

 Text needs to be added to provide greater clarification of how the proposed GCD 

AMP non-native fish management control program will be integrated with other existing 

or planned agency and tribal programs in fish resource management. The text should 

also address how this program would be integrated with the planned HBC Recovery 

Implementation Program (RIP) should it be initiated. 

 The segment of the plan addressing needed research to refine, enhance and 

support management control activities needs to be effectively integrated into the 

comprehensive biology programs currently in progress and planned at the GCMRC, 

especially the fish ecology programs. 

 The general organization of the proposed plan by GCMRC could be revised to 

provide more specificity to its primary objective i.e., proposing actions for non-native 

fish control. Major sections of the text could include: 

• Need and context for a Non-Native Fish Control Program 

• Risk to native fish habitat populations 

• Responding to legal mandates 

• Improving ecosystem conditions 

• Strategy for Non-Native Fish Control Program 

• Management and science program integration 

• Proposed short and long term control programs and supporting science 

• Control Programs 

• Research and monitoring programs 

• GCDAMP, agency and tribal implementation schedules 

• Resource requirements 

• Management agency and tribal management control costs 

• GCDAMP cooperative science programs and budgets needs 

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21

• Contingency plan and budget needs 

 The proposed planning of resource requirements and budget needs for 

implementation of the program should address the transition required from science 

activity to management actions. It should clarify individual agency program authorities 

and budget responsibilities, and how resolve of this issue would enhance program 

success.