Gateway West Transmission Line Final EIS

Appendix M

Biological Assessment
Biological Assessment

of

Threatened and Endangered Wildlife, Fish, and Plant Species

for the

Gateway West Transmission Line Project

Prepared by

Tetra Tech EC

Bothell, Washington

March 2013
Biological Assessment Gateway West Transmission Line Project

March 2013 i

TABLE OF CONTENTS

EXECUTIVE SUMMARY ......................................................................................................ES-1

1 PROJECT DESCRIPTION ................................................................................................ 1

1.1 Project Location and Action Area........................................................................... 6

2 METHODS ........................................................................................................................ 7

2.1 Published Literature and Agency Data................................................................... 7

2.2 Agency Input.......................................................................................................... 7

2.3 Field Surveys......................................................................................................... 7

2.4 Cumulative Effects................................................................................................. 8

3 ENVIRONMENTAL BASELINE, CURRENT STATUS, AND HABITAT USE...................11

3.1 Colorado River Species ........................................................................................16

3.2 Platte River Species..............................................................................................19

3.3 Mammals ..............................................................................................................21

3.3.1 Black-Footed Ferret (10(j) Nonessential, experimental population) ..............21

3.3.2 Canada Lynx (Threatened) ..........................................................................25

3.3.3 Grizzly Bear (Threatened)............................................................................29

3.3.4 Preble’s Meadow Jumping Mouse (Threatened) ..........................................33

3.4 Fish.......................................................................................................................36

3.4.1 Bull Trout (Threatened) ................................................................................36

3.5 Invertebrates.........................................................................................................39

3.5.1 Banbury Springs Limpet (Endangered) ........................................................39

3.5.2 Bliss Rapids Snail (Threatened)...................................................................42

3.5.3 Bruneau Hot Springsnail (Endangered)........................................................44

3.5.4 Snake River Physa Snail (Endangered) .......................................................46

3.6 Plants ...................................................................................................................48

3.6.1 Blowout Penstemon (Endangered)...............................................................48

3.6.2 Ute Ladies’-Tresses (Threatened)................................................................50

3.6.3 Slickspot Peppergrass (Proposed for Listing as Endangered)......................56

3.7 Cumulative Impacts ..............................................................................................69

4 IMPACTS.........................................................................................................................87

4.1 Colorado River Species ........................................................................................87

4.1.1 Direct and Indirect Effects ............................................................................87

4.1.2 Cumulative Effects .......................................................................................88

4.1.3 Critical Habitat..............................................................................................88

4.2 Platte River Species..............................................................................................88

4.2.1 Direct and Indirect Effects ............................................................................88

4.2.2 Cumulative Effects .......................................................................................89

4.2.3 Critical Habitat..............................................................................................89

4.3 Mammals ..............................................................................................................89

4.3.1 Black-Footed Ferret .....................................................................................89

4.3.2 Canada Lynx................................................................................................91

4.3.3 Grizzly Bear .................................................................................................93

4.3.4 Preble’s Meadow Jumping Mouse................................................................93

4.4 Fish.......................................................................................................................96

4.4.1 Bull Trout Critical Habitat..............................................................................96

4.5 Invertebrates.........................................................................................................97

4.5.1 Direct and Indirect Effects ............................................................................97

4.5.2 Cumulative Effects .....................................................................................101
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March 2013 ii

4.5.3 Critical Habitat............................................................................................102

4.6 Plants .................................................................................................................102

4.6.1 Blowout Penstemon ...................................................................................102

4.6.2 Ute Ladies’-Tresses ...................................................................................102

4.6.3 Slickspot Peppergrass................................................................................105

5 CONSERVATION MEASURES TO AVOID OR MINIMIZE ADVERSE IMPACTS .........107

5.1 Platte and Colorado River Species .....................................................................107

5.2 Black-footed Ferret .............................................................................................107

5.3 Canada Lynx ......................................................................................................107

5.4 Grizzly Bear........................................................................................................108

5.5 Preble’s Meadow Jumping Mouse ......................................................................108

5.6 Bull Trout ............................................................................................................108

5.7 Invertebrates.......................................................................................................108

5.8 Blowout Penstemon............................................................................................108

5.9 Ute Ladies’-Tresses............................................................................................109

5.10 Slickspot Peppergrass ........................................................................................109

6 INTERRELATED AND INTERDEPENDENT ACTIONS.................................................110

7 IRREVERSIBLE OR IRRETRIEVABLE COMMITMENT OF RESOURCES...................110

8 EFFECTS OF THE PROJECT ON THE EXPECTED STATUS OF SPECIES IN THE 

FUTURE ........................................................................................................................111

9 DETERMINATION OF EFFECTS SUMMARY FOR LISTED SPECIES .........................111

9.1 Colorado River Species ......................................................................................111

9.2 Platte River Species............................................................................................112

9.3 Black-Footed Ferret ............................................................................................112

9.4 Canada Lynx ......................................................................................................112

9.5 Grizzly Bear........................................................................................................112

9.6 Preble’s Meadow Jumping Mouse ......................................................................113

9.7 Bull Trout ............................................................................................................113

9.8 Invertebrates.......................................................................................................113

9.9 Blowout Penstemon............................................................................................113

9.10 Ute Ladies’-Tresses............................................................................................114

9.11 Slickspot Peppergrass ........................................................................................114

10 REFERENCES CITED ...................................................................................................116
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LIST OF TABLES

Table 2-1. Cumulative Effects Analysis Areas, by Species .................................................. 9

Table 2-2. Data Sources of the Cumulative Effects Analysis...............................................10

Table 3-1. Federally Threatened and Endangered Wildlife and Plant Species in 

Idaho and Wyoming that were determined to not have the Potential to 

Occur in the Action Area ....................................................................................12

Table 3-2. Federally Threatened and Endangered Wildlife and Plant Species 

Occurring in Idaho and Wyoming, Whether Each is Analyzed in the 

Biological Assessment, and the Rationale .........................................................15

Table 3-3. Number of Black-Tailed and White-Tailed Prairie Dog Colonies Crossed 

by the Project.....................................................................................................25

Table 3-4. Ute Ladies’-tresses Survey Results: Segment 1W .............................................54

Table 3-5. Ute Ladies’-tresses Survey Results: Segment 5 ................................................55

Table 3-6. Acres of Known Occurrences of Slickspot Peppergrass within the Action 

Area and Crossed by the Project Footprint, by Element Occurrence..................64

Table 3-7. Acres of Slickspot Peppergrass Occupied Habitat within the Action Area 

and Bisected by the Project Footprint, by Element Occurrence..........................65

Table 3-8. Acres of Potential Habitat and Slickspot Peppergrass Habitat and within 

the Action Area and Project Footprint.................................................................65

Table 3-9. HIP Transect and Associated EOs and Management Area within the 

Action Area ........................................................................................................66

Table 3-10. Unseeded Non-native Plant Cover (Percent) (Colket 2009; Kinter et al. 

2010, 2011, 2012)..............................................................................................66

Table 3-11. Seeded Non-native Plant Cover (Percent) (Colket 2009; Kinter et al. 

2010, 2011, 2012)..............................................................................................67

Table 3-12. Biological Soil Crust Cover in HIP Transect Slickspots (Percent) (Colket 

2009; Kinter et al. 2010, 2011, 2012) .................................................................67

Table 3-13. Population Data – Total Slickspot Peppergrass Plants (Colket 2009; 

Kinter et al. 2010, 2011, 2012)...........................................................................68

Table 3-14. Acres of Proposed Critical Habitat, by Subunit, within the Action Area...............68

Table 3-15. Acres of Proposed Critical Habitat within the Project Footprint, by Subunit 

and Project Component .....................................................................................69

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis..................70

Table 3-17. Proposed (i.e., Reasonably Foreseaable) Projects Considered within the 

Cumulative Effects Analysis...............................................................................85

Table 4-1. Acres of Vegetation Types that Would Be Affected During Construction 

and Operations ..................................................................................................87

LIST OF FIGURES

Figure 1-1. Gateway West Transmission Line Proposed Action – BLM Preferred 

Route.................................................................................................................. 2

Figure 3-1. Critical Habitat for the Four Species of Endangered Fish in the Colorado 

River Basin Addressed under the Upper Colorado Endangered Fish 

Recovery Program.............................................................................................18

Figure 3-2. Designated Whooping Crane Critical Habitat in relation to the Gateway 

West Project ......................................................................................................20
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March 2013 iv

Figure 3-3. Black-footed Ferret Range and Predicted Distribution........................................24

Figure 3-4. Canada Lynx Linkage Areas, Critical Habitat, and Analysis Units in the 

Action Area for the Gateway West Transmission Line Project Route .................27

Figure 3-5. Borders of the Primary Conservation Area, Suitable Habitat, and the 

Distinct Population Segment (DPS) of Yellowstone DPS Grizzly Bears, 

and the Gateway Transmission Line Route........................................................31

Figure 3-6. Preble’s Meadow Jumping Mouse Critical Habitat in Relation to the 

Gateway West Transmission Line Project Location............................................35

Figure 3-7. Distribution and Recovery Areas for Banbury Springs Limpet, Bliss 

Rapids Snail, Bruneau Hot Springsnail, and Snake River Physa Snail...............40

Figure 3-8a. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and 

Potential Habitat in relation to the Project (Map 1) .............................................60

Figure 3-8b. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and 

Potential Habitat in relation to the Project (Map 2) .............................................61

Figure 3-8c. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and 

Potential Habitat in relation to the Project (Map 3) .............................................62

Figure 3-8d. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and 

Potential Habitat in relation to the Project (Map 4) .............................................63

LIST OF ATTACHMENTS

Attachment A Definitions of Habitat Categories and Effect Assessment for Slickspot 

Peppergrass

Attachment B Limiting Factors Analysis for Bull Trout Critical Habitat
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ACRONYMS AND ABBREVIATIONS

°F degrees Fahrenheit

BA Biological Assessment

BLM Bureau of Land Management

BMP best management practice

CFR Code of Federal Regulation

CHU Critical Habitat Unit

CWA Clean Water Act

DPS distinct population segment

EA Environmental Assessment

EIS Environmental Impact Statement

EO element occurrence

EPM environmental protection measure

ESA Endangered Species Act

ESU evolutionarily significant unit

Forest Service U.S. Department of Agriculture, Forest Service

Gateway West Gateway West Transmission Line Project

GIS geographic information system

HIP Habitat Integrity and Population

IDFG Idaho Department of Fish and Game

IPaC Information, Planning, and Conservation System

kV kilovolt

LAU lynx analysis unit

LWD large woody debris

NEPA National Environmental Policy Act

NF National Forest

PCA Primary Conservation Area

PCE Primary Constituent Element

POD Plan of Development

Project Gateway West Transmission Line Project

Proponents Idaho Power Company and Rocky Mountain Power

PRRIP Platte River Recovery Implementation Program
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RM river mile

ROW right-of-way

SPCC Spill Prevention, Containment, and Countermeasures

SWPPP Stormwater Pollution Prevention Plan

UCEFRP Upper Colorado Endangered Fish Recovery Program

USACE U.S. Army Corps of Engineers

USFWS U.S. Fish and Wildlife Service

WGFD Wyoming Game and Fish Department
Biological Assessment Gateway West Transmission Line Project

March 2013 ES-1

EXECUTIVE SUMMARY

This biological assessment (BA) assesses the effects of the Bureau of Land 

Management’s (BLM’s) approval of the right-of-way (ROW) for construction and 

operations of the Gateway West Transmission Line Project (Project) on threatened and 

endangered wildlife, fish, and plant species identified by the U.S. Fish and Wildlife 

Service (USFWS) as having the potential to be affected by the Project. The

transmission line ROW would run from the Windstar Substation in Wyoming, just east of 

Glenrock, to the Hemingway Substation in Idaho, just west of Melba. The line would 

cross about 990 miles of private, state, and federal lands within Converse, Natrona, 

Carbon, Sweetwater, and Lincoln Counties in Wyoming; and Bear Lake, Franklin, 

Bannock, Power, Cassia, Twin Falls, Minidoka, Blaine, Lincoln, Jerome, Gooding, 

Owyhee, Elmore, and Ada Counties in Idaho. Table ES-1 summarizes the species 

considered in development of this BA, their statuses, and their corresponding 

determinations of effect. 

Table ES-1. Federally Threatened and Endangered Wildlife and Plant Species Occurring in 

Idaho and Wyoming, Their Effect Determinations, and the Rationale

Species Status

Effect 

Determination Rationale

Colorado River Species

Colorado 

pikeminnow

(Ptychocheilus 

lucius)

Endangered

May affect, 

likely to 

adversely affect

It is estimated that annual depletions would be 

0.3 acre feet from the Colorado River basin for 

use by the Project. The Proponents have 

committed to purchasing enough water to 

cover the extent of estimated water 

withdrawals from the Colorado River system 

for which consultation has already occurred; 

however, because the Proponents cannot yet 

identify the exact location for sources or 

precise amount of water per location that they 

plan to purchase until these water source 

locations and amounts have been fully 

identified, current project estimates for water 

usage lead to a threat determination for this 

Project of “may affect, likely to adversely 

affect” for the Colorado River endangered 

fishes, and a “may affect, not likely to 

adversely affect” their designated critical 

habitat.

Razorback sucker

(Xyrauchen texanus) Endangered

Bonytail chub

(Gila elegans) Endangered

Humpback chub

(Gila cypha) Endangered

Critical habitat for 

the four endangered 

Colorado River fish

Designated

May affect, not 

likely to 

adversely affect

critical habitat

Platte River Species

Interior least tern 

(Sterna antillarum 

athalassos)

Endangered

May affect, 

likely to 

adversely affect

It is estimated that annual depletions would be 

0.4 acre feet from the Platte River basin for 

use by the Project. The Proponents have 

committed to purchasing water from existing 

sources to cover the extent of estimated water 

withdrawals from the Platte River system and 

for which consultation has already occurred; 

however, the Proponents have not yet 

identified the sources or secured this water to 

date. Therefore, until these water sources

Piping plover

(Charadrius 

melodus)

Threatened

Whooping crane

(Grus americana) Endangered
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March 2013 ES-2

Table ES-1. Federally Threatened and Endangered Wildlife and Plant Species Occurring in 

Idaho and Wyoming, Their Effect Determinations, and the Rationale (continued)

Species Status

Effect 

Determination Rationale

Pallid sturgeon

(Scaphirhynchus 

albus)

Endangered

May affect, 

likely to 

adversely affect

and the precise amounts from each source 

have been fully identified, the threat 

determination for this Project is “may affect, 

likely to adversely affect” for these Platte River 

species, and “may affect, not likely to 

adversely affect” regarding their designated 

critical habitat.

Western prairie 

fringed orchid

(Platanthera 

praeclara)

Threatened

Whooping crane 

critical habitat Designated

May affect, not 

likely to 

adversely affect

critical habitat

Mammals

Black-footed ferret

(Mustela nigripes)

Endangered No effect

Based on recent determination by the U.S. 

Fish and Wildlife Service (USFWS March 6 

Letter to Scott Talbott, Director - Wyoming 

Game and Fish Department), the entire State 

of Wyoming has been block cleared, relaxing 

the requirements of Section 7 Consultation. 

No surveys would be required based on the 

agreement for block clearance, and it is 

determined that because wild endangered 

black-footed ferret populations are no longer 

present outside of the reintroduced 

populations ferrets, wild, free-ranging 

endangered ferrets would not be impacted by 

this project

10(j) 

Nonessential, 

experimental 

population

May affect, not 

likely to 

adversely affect

Unlikely to be encountered, and agencyrequired Environmental Protection Measures 

(EPMs) would be implemented. This species 

is included for agency coordination purposes.

Canada lynx

(Lynx canadensis) Threatened

May affect, not 

likely to 

adversely affect

Unlikely to be encountered, no critical habitat 

or LAUs impacted; however, two linkage 

areas would be crossed.

Grizzly bear 

(Ursus arctos) Threatened

May affect, not 

likely to 

adversely affect

Unlikely to be encountered, species is highly 

mobile, and the Project would affect only small 

portion of any individual’s home range which 

is located adjacent to an existing freeway.

Preble’s meadow 

jumping mouse

(Zapus hudsonius 

preblei)

Threatened

May affect, not 

likely to 

adversely affect

Unlikely to be encountered; however, surveys 

would be conducted in suitable habitat and 

occupied areas would be avoided during 

construction.

Fish

Bull trout critical 

habitat Designated

May affect, not 

likely to 

adversely affect

Critical habitat would be spanned by the 

transmission line, but no habitat disturbance 

would occur within the river and only limited 

disturbance in the riparian area (i.e., individual 

trees may be removed).
Biological Assessment Gateway West Transmission Line Project

March 2013 ES-3

Table ES-1. Federally Threatened and Endangered Wildlife and Plant Species Occurring in 

Idaho and Wyoming, Their Effect Determinations, and the Rationale (continued)

Species Status

Effect 

Determination Rationale

Invertebrates

Banbury Springs 

limpet

(Lanx sp.)

Endangered

May affect, not 

likely to 

adversely affect

A recovery area is located within the Action 

Area; however, this area would not be 

crossed by the line or any roads.

Bliss Rapids snail

(Taylorconcha 

serpenticola)

Threatened

May affect, not 

likely to 

adversely affect

A recovery area is located within the Action 

Area; however, it would be spanned, with no 

road crossings proposed.

Bruneau hot 

springsnail 

(Pyrgulopsis 

bruneauensis)

Endangered

May affect, not 

likely to 

adversely affect

A recovery area is located within the Action 

Area; however, this area would not be 

crossed by the line or any roads, and no water 

withdrawals would occur from hot-springs in 

the Bruneau River.

Snake River physa 

snail

(Physa natricina)

Endangered

May affect, not 

likely to 

adversely affect

A recovery area is located within the Action 

Area; however, it would be spanned, with no 

road crossings proposed.

Plants

Blowout penstemon

(Penstemon 

haydenii)

Endangered No Effect The Action Area does not intercept this 

species’ current distribution.

Ute ladies’-tresses

(Spiranthes 

diluvialis)

Threatened

May affect; not 

likely to 

adversely affect

The Action Area does not intercept any known 

occurrences of this species; however, it would 

cross this species known range. Surveys 

would be conducted and all occupied areas 

would be avoided during construction.

Slickspot 

peppergrass 

(Lepidium 

papilliferum)

Proposed 

Endangered

May affect, 

likely to 

adversely affect

Action Area intersects occupied habitat, 

slickspot peppergrass habitat, and potential 

habitat for this species, and some impacts to 

the species and its habitat are anticipated.

Slickspot 

peppergrass critical 

habitat

Proposed

May affect, 

likely to 

adversely affect

Action Area intersects proposed critical 

habitat for this species, and some impacts to 

PCEs are anticipated.
Biological Assessment Gateway West Transmission Line Project

March 2013 1

1 PROJECT DESCRIPTION

This Biological Assessment (BA) discusses the potential effects of the proposed 

Gateway West Transmission Line Project (Gateway West or Project) in Idaho and 

Wyoming on threatened and endangered wildlife, fish, and plant species pursuant to the 

Endangered Species Act (ESA) of 1973, as amended. This BA has been prepared for 

the purpose of consultation with the U.S. Fish and Wildlife Service (USFWS) on the 

expected effects of the agency preferred alternative on species listed under the ESA. 

This BA also presents conservation measures that would be applied to avoid or 

minimize the likelihood of impacts to listed species or their designated critical habitats. 

On May 7, 2007, Idaho Power Company and Rocky Mountain Power (the Proponents) 

applied to the Bureau of Land Management (BLM) for a right-of-way (ROW) grant to use 

public lands for portions of the Project. An Environmental Assessment (EA) and 

Environmental Impact Statement (EIS) have been prepared for this Project, and are 

incorporated into this BA by reference. The aboveground transmission line would

supplement existing transmission lines to relieve existing congestion, capacity, and 

reliability constraints in the electric transmission grid, allowing for the delivery of up to 

1,500 megawatts of energy. The Project would primarily serve future needs in Utah and 

Idaho. 

The Project’s construction is expected to begin after the Record of Decision is released 

in 2015, and be complete by December 2021, with multiple contractors working 

concurrently on the separate line segments and substations of the Project in order to 

meet the planned in-services dates. The last segment of the initial phase between 

Windstar and Populus would be completed by 2018. The second phase would extend 

from Populus to Hemingway with the last segment completed by the end of 2021.

The proposed federal action for consultation is the BLM’s approval of the applied for 

ROW grant for the construction and operation of an electric transmission system 

reaching from the Windstar Substation at Glenrock, Wyoming, and the Hemingway 

Substation just west of Melba and approximately 30 miles southwest of Boise, Idaho 

(Figure 1-1). Although route and structure alternatives for the Project have been 

proposed, only the route and alternatives preferred by the BLM will be analyzed in this 

BA. The proposed ROW grant includes the following Proponent actions:

• Construction and operations of about 990 miles of new 230-kilovolt (kV) and 500-

kV electric transmission lines in 10 segments, from Segment 1W at the eastern 

end in Wyoming to Segment 10 in Idaho; 

• Construction of permanent and temporary access roads; 

• Construction of permanent and temporary laydown and staging areas; 

• Construction of three substations; 

• Expansions or modifications of nine existing substations; and

• Construction or installation of other associated facilities including communication 

systems, optical fiber regeneration stations, and substation distribution supply 

lines. 
Biological Assessment Gateway West Transmission Line Project

March 2013 2

Figure 1-1. Gateway West Transmission Line Proposed Action – BLM Preferred Route
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March 2013 3

The Project would be supported by two types of transmission structures: steel H-frame 

230-kV structures and single 500-kV lattice steel towers. The installation of these 

structures requires preparation of each site, including vegetation removal and grading in 

order to obtain a relatively flat surface (necessary for the operation of the large cranes 

used to install the structures). Clearing individual structure sites would be done using a

bulldozer to blade the required area, which would be moved to staging areas by flatbed 

trucks along existing access roads. For construction laydown, tower assembly, and 

tower erection, areas measuring approximately 250 feet by 250 feet for each singlecircuit 500-kV structure and 150 feet by 125 feet for each 230-kV structure would be 

required. 

The 230-kV steel H-frames would be made of self-weathering steel. The average 

distance between H-frame structures would be approximately 700 feet. Typically, the 

230-kV single-circuit H-frame structures would have pole lengths ranging between 70 

and 100 feet. Embedment depths (for pole placements) are typically 10 percent of the 

pole length plus 2 feet (in the case of this Project, ranging from 9 to 12 feet). The 

structure heights above ground vary from 60 to 90 feet. 

The 500-kV lattice steel towers would be fabricated with galvanized steel treated to 

produce a dulled finish. The average distance between 500-kV towers would be 1,200 

to 1,300 feet. Structure heights would vary depending on terrain and the requirement to 

maintain minimum conductor clearances from ground (i.e., clearance requirement 

between the transmission line and the ground is at least 100 feet and clearance 

requirement between the line and any vegetation is at least 50 feet; see Appendix B of 

the EIS). The 500-kV towers would vary in height from 145 to 180 feet. The permanent

(for the 50-year life of the Project) foundations would be approximately 46 by 41 feet 

(0.43 acre).

Once the towers are assembled and in place, the conductors and the overhead ground 

wires would be strung. This is generally accomplished using a helicopter, but may be 

conducted from the ground if an access road that travels directly between towers is 

available or constructed. All areas not needed for normal transmission line 

maintenance, including fire and personnel safety clearance areas, would be graded 

following construction to blend as closely as possible with the natural contours and 

revegetated as required (Appendix B of the EIS contains the Proponents’ Plan of 

Development [POD], which includes their Reclamation Plan, postconstruction 

monitoring plan, as well as the success criteria they would use to assess 

revegetation/restoration success).

A communication system is required to control the transmission line and manage the 

flow of electricity. The backbone of this proposed communication system is a fiber optic 

wire contained within one of the overhead grounding wires that would be carried along 

the length of the transmission system. The fiber optic signal needs to be “boosted” or 

regenerated about every 55 miles along the system, which requires and optical signal 

regeneration station. These stations consist of a building, a fenced yard, access road, 

and distribution power supply from the local distribution system and are typically housed 

within a substation control house. However, if new sites need to be constructed (e.g., in 

places where substations are not located at sufficient distances for a regeneration 
Biological Assessment Gateway West Transmission Line Project

March 2013 4

station), then new lands will need to be developed. These optical fiber regeneration 

stations consist of a building 12 by 32 by 9 feet tall, a fenced yard, access road, and 

distribution power supply from the local distribution system. They would occupy a 100-

foot by 100-foot cleared area, with a fenced area of 75 feet by 75 feet. They are 

typically built as close to the transmission line as land use and physical features allow 

(more details about the optical fiber regeneration stations can be found in the 

“Transmission Line and Substation Components” section in Appendix B of the EIS).

The Project would include three new substations and expansions or modifications at 

nine existing substations. Construction of the proposed Anticline, Aeolus, and Cedar 

Hill Substations would be needed to electrically connect the new transmission line 

segments. Expansions of the yards at the Windstar, Heward, Jim Bridger, Populus, 

Borah, and Midpoint Substations would be required in order to accommodate the new 

line. Modifications at the Dave Johnston Power Plant, Shirley Basin, and Hemingway

Substations would also be required to accommodate the new line; however, no 

additional disturbance acreage would be needed.

The Project would require vehicular access to each structure during construction and 

periodically for inspection and live-line maintenance for the life of the Project (50 years). 

New access roads or improvements to existing access roads would be constructed 

using a bulldozer or grader, followed by a roller to compact and smooth the ground. 

Front-end loaders would be used to move the soil locally or off site. Typically, access to 

the transmission line ROW and tower sites requires a 14-foot-wide travel way for 

straight sections of road and a 16- to 20-foot-wide travel way at corners to facilitate safe 

movement of equipment and vehicles; however, construction disturbance along 

streambeds for crossings would disturb, on average, about 26 feet for the simpler 

crossings, up to 50 feet where permanent culverts would be installed. Wherever 

possible, new access roads would be constructed within the proposed transmission line 

ROW or existing roads would be used. In other cases, access roads would be required 

between the proposed transmission line and existing roads. Erosion control and 

sedimentation measures such as water bars, culverts, sediment basins, or perimeter 

control would be installed as required to minimize erosion on all lands, regardless of 

ownership, during and subsequent to construction of the Project. Roads retained for 

operations would be seeded with a native grass mix and allowed to revegetate. For 

normal maintenance activities, an 8-foot portion of the road would be used and vehicles 

would drive over the vegetation. For non-routine maintenance that requires access by 

larger vehicles, the full width of the access road (14 to 20 feet) may be used. Access 

roads would be repaired as necessary but not be routinely graded. Vegetation such as

taller shrubs and trees that may interfere with the safe operation of equipment would be 

managed on a cyclical basis. A total of 872.9 miles of new roads would be constructed,

and 914.6 miles of existing roads would be improved.
Biological Assessment Gateway West Transmission Line Project

March 2013 5

Areas used during construction but not needed during Project operation, for example 

staging areas, temporary roads, and fly yards, would be restored to their previous 

condition through reclamation procedures. Reclamation goals would include the 

replacement and stabilization of previously-existing vegetation, soil stabilization, and 

weed control. Methods used would include:

• stripping, stockpiling, and re-applying topsoil material at temporarily disturbed 

areas to restore soil horizons, use the existing seedbank, and establish surface 

conditions that would allow for the rapid re-establishment of vegetative cover;

• restore previously existing drainage patterns, minimize surface erosion and 

sedimentation, and facilitate plant establishment; and

• conducting post-construction weed monitoring for 3 years (see Appendix B of the 

EIS for more information on reclamation).

To ensure prompt restoration of vegetation following disturbance and to minimize the 

spread of weeds, the following environmental protection measure (EPM) would apply on 

all lands, regardless of ownership:

OM-15 To help limit the spread and establishment of noxious weed species in 

disturbed areas, desired vegetation needs to be established promptly 

after disturbance. The Proponents will rehabilitate significantly 

disturbed areas as soon as possible after ground-disturbing activities 

and during the optimal period. Seed and mulch will be certified 

“noxious weed free” and seed mix will be agreed to in advance by the 

landowner or land managing agency.

Operations and maintenance activities would include transmission line patrols, climbing 

inspections, tower and wire maintenance, insulator washing in selected areas as 

needed, and access roads repairs. The Proponents would keep necessary work areas 

around structures clear of vegetation and would limit the height of vegetation along the 

ROW. Periodic inspection and maintenance of each of the substations and 

communications facilities is also a key part of operating and maintaining the electrical 

system.

Impacts from construction on listed fish, plant, and wildlife species would include habitat 

removal, fragmentation, and alteration; ecological changes such as changes in predator 

or prey densities; noise and visual disturbance to foraging, breeding, and migrating 

animals; increased sedimentation in waterbodies; trampling; and vehicle collisions. 

Impacts from operations on listed fish, plant, and wildlife species would include noise 

and visual disturbance from project personnel and other human presence in the Action 

Area (Action Area defined in Section 1.1), habitat fragmentation, alteration of 

hydrological regimes, spread of invasive plants, potential alterations to the local fire 

regime (due to project-related ignitions as well as increased extent of invasive weeds 

increasing the rate and intensity of fire regimes), blockage of stream passage for fish, 

and reductions in large woody debris (LWD) input in streams and on the forest floor. 

These impacts would be minimized or avoided through EPMs and best management 

practices (BMPs). These are listed in Section 5, Conservation Measures to Avoid or 

Reduce Adverse Impacts, and in Table 2.7-1 of the EIS. 
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In addition, revegetated and restored areas would be monitored for 3 years to ensure 

that successful revegetation occurs, and to identify areas where additional measures 

would be required if successful revegetation/restoration does not occur (see REC-1 

through REC-15 and REC-17 in Table 2.7-1 of Chapter 2 in the EIS). This effort was 

not deemed sufficient on federally managed lands, however, and thus the following 

measures would be required on federally managed lands (as well as state managed 

and privately owned lands in Wyoming; see Table 2.7-1 of Chapter 2 in the EIS):

VEG-8 Annual post-construction monitoring and treatment of invasive plants on 

closed roads (access roads dedicated for use by Proponents only), 

temporary roads, fly yards, and other disturbed areas in the ROW shall 

continue for 3 years in areas where infestations or populations of noxious 

weeds have been identified. If after 3 years post-construction conditions are 

not equivalent to or better than pre-construction conditions (in accordance 

with applicable permit), monitoring and treatment will continue until these 

conditions are met. If adjacent land uses are contributing to the introduction 

and/or persistence of invasive plant species within areas disturbed by the 

project, then Proponents will not be required to treat noxious weeds for more 

than three years. 

The permitted life of the Project would be 50 years. The assessment of this Project 

includes the construction of the Project, the 50-year permitted life of the Project, as well 

as the10 years it is estimated to take for substantial site rehabilitation following 

decommissioning. Impacts resulting from decommissioning would be identical to those 

described for construction, such as habitat removal, fragmentation, and alteration; 

ecological changes such as changes in predator or prey densities; noise and visual 

disturbance to foraging, breeding, and migrating animals; increased sedimentation in 

waterbodies; trampling; and vehicle collisions

1.1 Project Location and Action Area

The total length of the proposed, BLM Preferred Route of the transmission line is about 

990 miles on private, state, and federal lands. The route is located in Converse, 

Natrona, Carbon, Sweetwater, Uinta, and Lincoln Counties in Wyoming; and Bear Lake, 

Franklin, Bannock, Oneida, Power, Cassia, Twin Falls, Minidoka, Blaine, Lincoln, 

Jerome, Gooding, Owyhee, Elmore, Ada, and Canyon Counties in Idaho (Figure 1-1). 

The Action Area must include all areas where any direct and indirect effects to the 

environment may be documented regardless of the presence or absence of a listed 

species (50 Code of Federal Regulations [CFR] §402.02). Therefore, it includes the 

ROW; access roads (both new roads and existing roads requiring improvement); 

substations (both proposed substations and existing substations requiring expansion); 

and yards for material storage, helicopter operations, and other purposes; and a 0.5-

mile buffer around these areas. Although they do not occur in the Action Area, certain 

listed species that occur in the Colorado River and Platte River basins downstream of 

the Wyoming portions of the Project will be assessed in this BA due to impacts from 

Project-related water withdrawals, as required by the Upper Colorado Endangered Fish 

Recovery Program (UCEFRP) and the Platte River Recovery Implementation Program 

(PRRIP). 
Biological Assessment Gateway West Transmission Line Project

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2 METHODS

The assessments and recommendations contained within this BA are based upon 

information obtained from several sources: published literature, unpublished agency 

reports and data, state and federal agency biologists, and field surveys.

2.1 Published Literature and Agency Data

Preliminary investigations included review of information and literature obtained from 

the USFWS, Wyoming Game and Fish Department (WGFD), Idaho Department of Fish 

and Game (IDFG), U.S. Department of Agriculture, Forest Service (Forest Service), and 

the BLM. The USFWS, BLM, Forest Service, and the state wildlife agencies in Idaho 

and Wyoming work closely together to develop, maintain and update a database of 

known occurrences of many wildlife and plant species, including all listed species 

described here; however, there are still important occurrence, habitat, and potential 

habitat data insufficiencies. Additional information was obtained from independent 

literature searches, examination of aerial photographs, and queries of Geographic 

Information System databases including IDFG’s Natural Heritage Program, the 

Wyoming Natural Diversity Database, and other databases maintained by the BLM, 

Forest Service, IDFG, and WGFD regarding known and potential locations of listed 

species and their habitats within the Action Area. 

2.2 Agency Input

Agency personnel who provided input on the preparation of this BA included Ms. 

Barbara Chaney (USFWS, Idaho), Ms. Julie Reeves (USFWS, Wyoming), Ms. Jeri 

Wood (USFWS, Idaho), Ms. Patricia Sweanor (USFWS, Wyoming), Mr. Frank 

Blomquist (BLM Biologist, Rawlins), Mr. Tim Carrigan (BLM Biologist, Idaho), Mr. Chris 

Keefe (BLM Biologist, Cheyenne), Ms. Kate Forster (BLM Biologist, Twin Falls), Mr. Jeff 

Carroll (BLM Biologist, Wyoming), Mr. Brandon Knapton (BLM Resource Coordinator, 

Boise), Ms. Lorraine Keith (BLM, Rock Springs), Mr. Paul Makela (BLM Wildlife 

Biologist, Boise), Ms. Ann Keysor (Forest Service, Caribou-Targhee National Forest 

[NF]), and Mr. Dennis Duehren (Forest Service, Caribou-Targhee NF).

2.3 Field Surveys

Surveys for Ute ladies’-tresses were completed in portions of the Action Area in 2009, 

2010, 2011, 2012 by Tetra Tech and URS (Tetra Tech 2010, 2011, 2013), using 

USFWS protocol for this species (USFWS 1992a). Based on review of habitats and 

elevations in the Action Area and information provided from the BLM, USFWS, Forest 

Service, Wyoming Natural Diversity Database, and IDFG, it was determined that 

portions of Segment 1W in Wyoming and Segment 5 in Idaho had the highest likelihood 

of containing suitable potential habitat for Ute ladies’-tresses. Prior to conducting field 

surveys, 27 areas, 22 along Segment 1W and 5 along Segment 5, were identified for 

surveys. Meandering pedestrian surveys were conducted along accessible stream 

features or other areas of potential habitat and habitat characteristics were assessed. 

Areas containing suitable potential habitat for Ute ladies’-tresses were noted; no 

individuals of this species were observed during surveys.
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Surveys in 2010 and 2012 were conducted during the USFWS interim survey protocol 

window (July 20–August 31), while surveys conducted in both 2009 and 2011 occurred 

between August 31 and September 4, just after the end of the period recommended by 

the USFWS’ interim survey protocol for Ute ladies’-tresses (USFWS 1992a). The 2009 

and 2011 surveys, however, were conducted during the range (mid-July to midSeptember) suggested in the Ute ladies’-tresses survey protocol published in 2011 by 

the BLM (BLM 2011a). Additionally, the timing of the surveys likely did not impact the 

results because little or no suitable habitat was documented within most of the areas 

surveyed during these years. Most of the areas surveyed in 2009 and 2011 were too 

heavily vegetated and/or disturbed by grazing to support the species. Other sites either 

lacked a floodplain or did not exhibit suitable hydrological characteristics. 

2.4 Cumulative Effects

Cumulative impacts, in regard to an ESA analysis, include those effects of future state, 

private, or tribal activities (not involving Federal activities) that are reasonably certain to

occur within the action area of the Federal action subject to consultation (50 CFR 

§402.02). Research was carried out to determine such projects that, when taken 

together with Gateway West, could have cumulative environmental impacts. Projects 

included in the assessment were those already in operation (i.e., existing projects that 

contribute to the existing environment), and those expected to take place during the 50-

year life of Gateway West plus the 10 years it is estimated to take for substantial site

rehabilitation following decommissioning. This list of projects includes activities that are 

known to the public through formal announcement and includes projects that have 

applied for a permit from a state or local agency. In some cases these projects are “on 

hold” and are not being actively pursued because of financial uncertainty; however, 

these projects are still listed in this section and considered in this analysis if the project 

proponent has not withdrawn the permit application from the state or local permitting 

entity. Note that federal actions are included in the list of past and existing projects, as 

these projects contribute to the existing baseline conditions of the area; however, 

reasonable foreseeable actions/projects in this analysis are limited to private and state 

actions as required by 50 CFR §402.02.

This cumulative effects analysis used the ranges for the species evaluated in the BA for 

its Analysis Area. These ranges were limited to the specific populations of interest (e.g., 

the distinct population segment assessed). Some species’ ranges were broken out for 

this assessment to encompass differences in species use or management designations. 

Table 2-1 details the species ranges used for the analyses. 

Streams were buffered during the analyses for aquatic species. For the Colorado, and 

North Platte Rivers, a 1-mile-wide buffer was analyzed from the stream centerline. This 

allowed the buffer to account for errors in stream digitization and variation in stream 

widths due to reservoir operations while still maintaining at least a 0.25-mile analysis 

distance from the river bank as a way to account for projects with potential water 

withdrawal activities in the stream corridor. The 0.25-mile minimum distance was 

selected as it is used in the North Platte Special Recreation Management Area for 

managing surface disturbing activities. Once projects were selected, they were 

reviewed for likelihood of impact to the area. Transmission line, pipeline, and road 
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crossings were not evaluated for impacts to Colorado and Platte River species, as the 

cumulative concern is regarding water withdrawals impacting flows downstream. 

Because the Snake River varies in width, a 0.25-mile buffer was used to capture the 

majority of the river and associated wetland habitat. The BLM uses this distance for 

restriction of surface disturbance from rivers as well. The Bruneau River centerline was 

buffered by 0.25 mile to conservatively estimate cumulative impacts to the Bruneau hot 

springsnail. The 0.25-mile distance is used by the BLM for surface disturbing activities. 

For the Bruneau River, this distance approximates the rim-to-rim distance of the 

canyon. Roads and stream crossings of all project types were evaluated for local 

impacts to the species.

Table 2-1. Cumulative Effects Analysis Areas, by Species

Species1/ Description

Grizzly bear The Greater Yellowstone Distinct Population Segment range

Lynx linkage habitat Generalized area to encompass lynx migration pathways 

within the population area near the project

Lynx habitat Includes Critical Habitat and Lynx Analysis Units within the 

population area near the project

Preble’s meadow jumping mouse Known range in Wyoming

Black-footed ferret 10J 10J population range and distribution

Bull trout Critical Habitat in the Upper Snake Recovery Unit, buffered 

500 feet 

Bruneau hot springsnail Bruneau River with 0.25 mile buffer from stream centerline

Snake River invertebrate species Snake River with 0.25 mile buffer from stream centerline

Colorado River species Colorado River with 1 mile buffer from stream centerline

Platte River species North Platte and Platte Rivers with 1 mile buffer from stream 

centerline

Slickspot peppergrass critical habitat Area considered for Critical Habitat designation

Slickspot peppergrass habitat Occupied and potential habitat areas

1/ Some species are broken out due to habitat/management use (Canada lynx and black-footed ferret), while others 

are grouped together (species in the Colorado, Snake and Platte Rivers), as effects are assessed in the BA as a unit.

Bull trout critical habitat is designated in Washington, Oregon, Idaho, and Montana, 

however only the Recovery Unit that would be crosses by the Project is the Upper 

Snake Recovery Unit. Therefore the cumulative effects analysis examined existing and 

potential projects within 500 feet of the designated critical habitat for bull trout in the 

Upper Snake Recovery Unit. The 500-foot buffer is reflective of the maximum riparian 

buffer distance used in many BLM management prescriptions. Roads and stream 

crossings of all project types were evaluated for local impacts to the species.

Additionally, while blowout penstemon and Ute’s ladies tresses are both species 

considered in the BA, specific data on existing habitat and occurrence were not 

available for cumulative assessment so data related to existing or reasonable 

foreseeable project in their range/habitat is not available. Potential projects such as 

additional development of mineral leases have the potential to impact these plant 

species by direct disturbance and water withdrawals, in addition to proposed actions 

such as wind farms and transmission line projects. 

Existing and potential projects that could occur within these ranges were quantified 

using the best available information. Data for power generation facilities, transmission 

lines, pipelines, roads, and mining were incorporated into this analysis. As oil wells are 
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extensive, the area for the leases and extent of oil and gas fields was assessed for 

additional impacts within the species’ ranges. Table 2-2 lists the data sources used in 

the cumulative effects analyses.

Table 2-2. Data Sources of the Cumulative Effects Analysis

Resource File Name Source Information

Mining 

Extraction

FEIS_Coal_Deposits_20121217 GIS file provided by Bothell office -

source is listed as Daniel Earnest

FEIS_Cumulative_Coal_Leases_20121217 BLM GeoCommunicator and LR2000

FEIS_Cumulative_OG_Leases_20121217 BLM GeoCommunicator and LR2000

FEIS_OG_Fields_20121217 Wyoming State Geologic Survey

FEIS_OG_Wells_IGS_20120709 Idaho Geologic Survey

FEIS_OG_Wells_WOGCC_20120709 Wyoming Oil and Gas Conservation 

Commission

FEIS_SM_Auth_20120722 BLM GeoCommunicator and LR2000

FEIS_Trona_Deposits_20121217 GIS file provided by Bothell office -

source is listed as Daniel Earnest

FEIS_Uranium_Permit_Areas_20121217 Parcels extracted from BLM GCDB 

based on BLM map of Lost Creek Project 

Power 

Generation

FEIS_Power_Generators_20130108 Various - see "Source" field in attribute 

table

wind_farms_region Ventyx 2012

Transmission 

lines

Ventyx_Tlines_Existing Ventyx 2012

Ventyx_Tlines_Proposed Ventyx 2012

Zephyr Digitized from online map originally at 

http://www.datcllc.com/datcprojects/zephyr/ 

Pipelines ng_pipe_polyline

maj_oil_pipe_polyline

Ventyx 2012

Roads Mjrrds ESRI

Only projects occurring within the selected species ranges were considered for the 

cumulative effects analysis. Projects were categorized by status (proposed or existing), 

project-type, jurisdiction, footprint, and species affected. Projects classified as “Federal” 

include those that trigger the National Environmental Policy Act (NEPA) process, 

usually by virtue of being sited on federal lands, including those owned or managed by 

the BLM, Forest Service, Bureau of Reclamation, and USFWS. NEPA may also be

triggered by non-land-based permitting or licensing, such as FERC licensing of 

hydropower plants. Federal nexus is not always inferable through raw geographic 

information system (GIS) data, though reasonable additional research was performed 

when necessary in order to ensure accurate reporting. Projects classified as “State” 

include projects existing or proposed for siting on lands owned or managed by a State 

agency (IDFG, for instance). The “Tribal” land, or Indian Reservation classification was 

based directly on the GIS data, and projects classified as “Private” are understood to be 

sited entirely on privately-owned lands, though in the case of proposed projects as the 

project proceeds, federal or state nexus may be triggered, thereby requiring a NEPA 

analysis. As described above, this is not always clear based on GIS data.
Biological Assessment Gateway West Transmission Line Project

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3 ENVIRONMENTAL BASELINE, CURRENT STATUS,

AND HABITAT USE 

The proposed Project would cross two major ecological zones: Temperate Steppe and 

Temperate Mountain. Ecoregions crossed are (from east to west): Northwestern Great 

Plains, Southern Rockies, Wyoming Basin, Wasatch and Uinta Mountains, Middle 

Rockies, and Northern Basin and Range. The most common vegetation types crossed 

by the Project are sagebrush/grasslands (41 percent of miles crossed), disturbed 

grassland (14 percent), disturbed sagebrush/grasslands (10 percent), and agriculture 

(10 percent). Other vegetation types present are dwarf shrub and greasewood (5 

percent each); juniper and saltbush (3 percent each); deciduous forest and conifer 

forest (2 percent each); wetland/riparian and disturbed/developed (1 percent each); and 

native grass, other shrub, water, and miscellaneous (less than 1 percent each). Most 

native shrublands and grasslands in the Action Area have had some level of

disturbance due to agriculture and rangeland practices, fire, residential developments, 

as well as industrial development (e.g., oil, gas, mining, wind-farms, pipelines, 

transmission lines). The existing baseline conditions of the general habitat along the 

Project are addressed in Sections 3.6.1.5, 3.7.1.5, 3.8.1.5, 3.9.1.5, 3.10.1.5, and 

3.11.1.5 of the EIS.

The list of threatened and endangered species considered for this Project was compiled 

for Wyoming by querying the Information, Planning, and Conservation System (IPaC), 

part of the Environmental Conservation Online System run by USFWS (list was 

generated on June 12, 2012); for Idaho, the list was compiled using “Endangered, 

Threatened, Proposed, and Candidate Species With Associated Proposed and Critical 

Habitats (Updated August 17, 2011),” from the USFWS Idaho Office (printed June 14, 

2012). 

The Proponents, in coordination with the USFWS, have determined that some of the

threatened and endangered species from this query do not have the potential to occur 

in the Action Area and therefore will not be fully analyzed in this BA. Table 3-1 lists the 

threatened and endangered species in Idaho and Wyoming that were determined not to 

have a potential to occur in the Action Area. The Project would have no effect to these 

species as they are not located within the Action Area, and as a result, they will not be 

addressed further within the BA.
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Table 3-1. Federally Threatened and Endangered Wildlife and Plant Species in Idaho and Wyoming that were determined to not 

have the Potential to Occur in the Action Area

Species Status

Fully Analyzed in this 

Biological Assessment? Rationale

Mammals

Northern Idaho ground 

squirrel

(Spermophilus brunneus 

brunneus)

Threatened No

This species has a very restricted range, and is only found in Adams and 

Valley Counties in west-central Idaho. The Project is not located in either 

one of these counties, and so does not overlap this species’ current range. 

The closest know occurrence of this species is located about 60 miles north 

of the Project’s Segment 8. As a result, the Project is not expected to impact 

Northern Idaho ground squirrel.

Selkirk Mountains 

woodland caribou

(Rangifer tarandus 

caribou)

Endangered No

This population of caribou is found in extreme northeastern Washington, 

northern Idaho, and southern British Columbia (48 Federal Register 1722). 

The closest this subspecies is found to the Project is along the Pend Oreille 

River in northern Idaho, approximately 300 miles to the north. As a result, 

the Project is not expected to impact Selkirk Mountains woodland caribou.

Fish

Bull trout

(Salvelinus confluentus) Threatened No

The Project crosses the Bruneau River, which has the potential to be used 

for foraging, migration, and overwintering by the Jarbidge River DPS of bull 

trout (USFWS 2004). At this time, bull trout have not been documented to 

use the Bruneau River, although the Bruneau River has been designated as 

bull trout critical habitat. Use of the Bruneau River by bull trout remains 

unconfirmed; therefore, the Project is not expected to impact bull trout.

Chinook salmon

(Oncorhynchus 

tshawytscha)

Threatened No

Two evolutionarily significant units (ESUs) of Chinook salmon occur in the 

vicinity of the Action Area: Snake River fall Chinook, and Snake River 

spring/summer Chinook. Snake River fall Chinook occur along the mainstem 

Snake River from the mouth in Washington to Hells Canyon Dam on the 

Oregon-Idaho border, and in the first few river miles of certain large tributaries, 

including the Tucannon, Grande Ronde, and Clearwater Rivers (Waples et al. 

1991). Adult fall Chinook migrate past Bonneville Dam on the Columbia River 

from August to October (Waples et al. 1991). Adult spring/summer Chinook 

migrate past Bonneville Dam from early March through August (Good et al. 

2005). Passage for both of these ESUs is blocked at Hells Canyon Dam on the 

Snake River, over 100 miles north of the Action Area. Hells Canyon Dam is the 

closest location of Snake River fall Chinook, while the Salmon River basin, 

approximately 70 miles to the north of the Action Area, is the closest occurrence 

of Snake River spring/summer Chinook.; therefore, the Project is not expected 

to impact Chinook salmon.
Biological Assessment Gateway West Transmission Line Project

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Table 3-1. Federally Threatened and Endangered Wildlife and Plant Species in Idaho and Wyoming that were determined to not 

have the Potential to Occur in the Action Area (continued)

Species Status

Fully Analyzed in this 

Biological Assessment? Rationale

Kendall warm springs 

dace

(Rhinichthys osculus 

thermalis)

Endangered No

This species is restricted to Kendall Warm Springs, which is approximately 

80 miles north of Segment 4 of the Project, and no Project activities would 

be taking place upstream of this species’ range. Therefore, the Project is not 

expected to impact Kendall Warm Springs dace.

Sockeye salmon

(Oncorhynchus nerka) Endangered No

The closest ESU of sockeye salmon to the Action Area is Snake River 

sockeye. The only extant population in this ESU is in Redfish Lake, 

approximately 80 miles to the north of Segment 8. Passage for this fish into 

the Action Area from the ocean is blocked by Hells Canyon Dam, 

approximately 100 miles north of the Action Area. Therefore, this Project is 

not expected to impact sockeye salmon.

Steelhead

(Oncorhynchus mykiss) Threatened No

The closest ESU of steelhead to the Action Area is Snake River steelhead. 

The passage of Snake River steelhead from the ocean into the Action Area

is blocked by Hells Canyon Dam, approximately 100 miles to the north. The 

closest these fish can be found to the Action Area as the crow flies is in the 

Salmon River basin, approximately 70 miles north of Segment 8. Therefore, 

the Project is not expected to impact steelhead.

White sturgeon 

(Kootenai River 

population)

(Acipenser 

transmontanus)

Endangered No

The closest area (in comparison to the Action Area) known to contain the 

Kootenai River population of white sturgeon is in the northern panhandle of 

Idaho, over 350 miles to the north. Therefore, the Project is not expected to 

impact white surgeon.

Amphibians

Wyoming toad

(Bufo baxteri) Endangered No

This species is known only from Mortenson Lake (NatureServe 2011), which 

is approximately 60 miles southeast of Segment 2 in Albany County. 

Therefore, the Project is not expected to impact the Wyoming toad.

Plants

Colorado butterfly plant

(Guara neomexicana

ssp. coloradoensis)

Threatened No

This plant’s range is limited to Laramie and Platte Counties in Wyoming, 

western Kimball County in Nebraska, and Weld County in Colorado. It is 

only known to occur in approximately 17 locations located in a small 

geographic area, measuring approximately 60 miles by 60 miles. The Action 

Area does not lie in either one of the Wyoming counties from which this plant 

is known; therefore, the Project is not expected to impact Colorado butterfly 

plant.
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Table 3-1. Federally Threatened and Endangered Wildlife and Plant Species in Idaho and Wyoming that were determined to not 

have the Potential to Occur in the Action Area (continued)

Species Status

Fully Analyzed in this 

Biological Assessment? Rationale

Desert yellowhead

(Yermo xanthocephalus) Threatened No

The desert yellowhead is sparsely distributed across an area of only 50 

acres in southeastern Fremont County, Wyoming (67 Federal Register

11442). The only known location where this species occurs, despite 

intensive survey efforts, is one small area of southeastern Fremont County, 

which is not in the Action Area. Therefore, the Project is not expected to 

impact desert yellowhead.

MacFarlane’s fouro’clock

(Mirabilis macfarlanei)

Threatened No

This plant occurs in Idaho and Oregon only at three sites: along the Snake 

River in Idaho County, Idaho; along the Salmon River in Idaho County, 

Idaho, and along the Imnaha River in Wallowa County, Oregon. The closest 

of these to the Action Area is about 130 miles to the north, and therefore the 

Project is not expected to impact MacFarlane’s four-o’clock.

Spalding’s catchfly

(Silene spaldingii) Threatened No

The closest known occurrence of Spalding’s catchfly to the Project is 

approximately 120 miles to the north, and therefore the Project is not 

expected to impact Spalding’s catchfly.

Water howellia

(Howellia aquatilis) Threatened No

Water howellia is known from Latah County, Idaho; Spokane, Clark, and 

Pierce Counties, Washington; and Lake and Missoula Counties, Montana 

(USFWS 1996b). The closest known occurrence of this plant to the Project 

is over 150 miles to the north, and therefore the Project is not expected to 

impact water howellia.
Biological Assessment Gateway West Transmission Line Project

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Table 3-2 lists all of the federally listed wildlife and plant species that could occur in the 

Action Area. As these species could occur within areas that would be affected by the 

Project they have been fully analyzed in this BA.

Table 3-2. Federally Threatened and Endangered Wildlife and Plant Species Occurring in 

Idaho and Wyoming, Whether Each is Analyzed in the Biological Assessment, 

and the Rationale

Species Status

Fully Analyzed in 

this BA? Rationale

Colorado River Species

Colorado pikeminnow

(Ptychocheilus lucius) Endangered

Yes

These species occur downstream of the 

Project in the Colorado River basin. 

Water withdrawals from the Colorado

River basin would occur due to the 

Project; therefore, the Project has the 

potential to affect these species.

Razorback sucker

(Xyrauchen texanus) Endangered

Bonytail chub

(Gila elegans) Endangered

Humpback chub

(Gila cypha) Endangered

Platte River Species

Interior least tern 

(Sterna antillarum 

athalassos)

Endangered

Yes

These species occur downstream of the 

Project in the Platte River basin. Water 

withdrawals from the Platte River basin 

would occur due to the Project; 

therefore, the Project has the potential to 

affect these species.

Piping plover

(Charadrius melodus) Threatened

Whooping crane

(Grus americana) Endangered

Pallid sturgeon

(Scaphirhynchus albus) Endangered

Western prairie fringed 

orchid

(Platanthera praeclara)

Threatened

Mammals

Black-footed ferret

(Mustela nigripes)

Endangered Yes 

The project traverses areas recently 

considered as non-block-cleared areas; 

however, the USFWS has recently 

block-cleared the entire State of 

Wyoming 

Nonessential, 

experimental 

population

Yes Borders of the 10(j) population would be 

crossed by the Project

Canada lynx

(Lynx canadensis) Threatened Yes Lynx linkage habitat would be crossed 

along Segment 4.

Grizzly bear 

(Ursus arctos) Threatened Yes

The Action Area passes through the 

southern part of the Yellowstone Distinct 

Population Segment.

Preble’s meadow jumping 

mouse

(Zapus hudonius preblei)

Threatened Yes Suitable habitat occurs within the Action 

Area.

Fish

Bull trout critical habitat Designated Yes Bull trout critical habitat is crossed by the 

Project
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Table 3-2. Federally Threatened and Endangered Wildlife and Plant Species Occurring in 

Idaho and Wyoming, Whether Each is Analyzed in the Biological Assessment, 

and the Rationale (continued)

Species Status

Fully Analyzed in 

this BA? Rationale

Invertebrates

Banbury Springs limpet

(Lanx sp.) Endangered Yes The entire known range of this species 

lies between Segments 8 and 9

Bliss Rapids snail

(Taylorconcha 

serpenticola)

Threatened Yes The entire known range of this species 

lies between Segments 8 and 9

Bruneau hot springsnail 

(Pyrgulopsis 

bruneauensis)

Endangered Yes The entire known range of this species is 

just south of Segment 9

Snake River physa snail

(Physa natricina) Endangered Yes The entire known range of this species 

lies between Segments 8 and 9

Plants

Blowout penstemon

(Penstemon haydenii) Endangered Yes

Detailed vegetation mapping indicates 

that no sand dune habitat occurs within 

the Action Area; however, the USFWS 

has indicated that all portions of the 

Action Area in Wyoming are within the 

potential range for this species (USFWS 

2012b); therefore, this species will be 

analyzed in this document.

Ute ladies’-tresses

(Spiranthes diluvialis) Threatened Yes

This plant could be found in potential 

habitat along Segments 1W, 2, 3, 4, and 

5.

Slickspot peppergrass 

(Lepidium papilliferum)

Proposed

Endangered Yes

Action Area intersects occupied habitat, 

slickspot peppergrass habitat, and 

potential habitat for this species, and 

despite incorporation of conservation 

measures some adverse impacts to the 

species and its habitat are anticipated.

The following subsections discuss the status, life history, and applicable baseline 

conditions for each listed species that could occur within the Action Area. Note that 

impacts to these species are discussed in Section 4.

3.1 Colorado River Species

The portion of the Action Area in southwestern Wyoming drains into the Colorado River 

watershed. The UCEFRP was established in 1988, and enacts conservation measures 

to minimize adverse effects to four endangered fish (Colorado pikeminnow, razorback 

sucker, humpback chub, and bonytail chub) and their critical habitat. This program 

addresses effects on these four listed fish and their critical habitat from water 

withdrawals that occur upstream of locations where these fish and their designated 

critical habitat occur. De minimis depletions (less than 0.1 acre-feet per year) require 

no depletion fee and would result in a no effect determination for the Colorado 

pikeminnow, razorback sucker, humpback chub, and bonytail chub and their designated 

critical habitat. Small depletions (between 0.1 and 100 acre-feet per year) require no 
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depletion fee, but would require consultation and would result in a may affect, likely to 

adversely affect determination for these fish species and a may affect, but not likely to 

adversely affect determination for their designated critical habitat. According to the 

UCEFRP, any depletions greater than 100 acre-feet per year require a one-time 

depletion fee, and depletions would require consultation, and determinations would be

may affect, likely to adversely affect for the fishes and a may affect determination for 

their critical habitat (McKee 2012a). However, the USFWS has indicated that if the 

entirety of this depletion is drawn from depletion locations for which consultation has 

already taken place, this project would not be considered to have additional withdrawal. 

This would result in no new effects to both the fish species and their designated critical 

habitat (McKee 2012a). If only part of water withdrawals can come from depletions for 

which consultation has taken place, the portion that has been consulted on can be 

subtracted from the total amount, and effects determinations may be based on the 

remaining amount. In order to calculate the number of acre-feet per year, the total 

amount of water withdrawn is divided over the life of the Project, not necessarily over 

the number of years during which water would actually be withdrawn (Abbott 2012). 

None of the four ESA-listed fish covered under the UCEFRP or their critical habitat 

(Figure 3-1) are found in the Action Area (USFWS 1990a, 2002c, 2002d, 2002e; 59 

Federal Register 13374); however, they do occur downstream of the Action Area and an 

analysis of effects is required based on the UCEFRP. 
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Figure 3-1. Critical Habitat for the Four Species of Endangered Fish in the Colorado River 

Basin Addressed under the Upper Colorado Endangered Fish Recovery Program
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3.2 Platte River Species

The eastern end of the Project, in central Wyoming, drains into the Platte River 

watershed. Federally listed species that could be affected by flow depletion in the Platte 

River watershed are the pallid sturgeon, interior least tern, and whooping crane, which 

are listed as endangered; and the piping plover and western prairie fringed orchid, 

which are listed as threatened. Portions of the Platte River are also designated as 

critical habitat for the whooping crane. Critical habitat for piping plover has been 

designated, but not in the Platte River basin; the other three species have no proposed 

or designated critical habitat. The PRRIP, established in 1997, implements actions 

designed to assist in the conservation and recovery of these target species and their 

associated habitats along the central and lower Platte River in Nebraska through a 

basin-wide cooperative approach agreed to by the states of Wyoming, Nebraska, and 

Colorado, as well as the U.S. Department of the Interior. The PRRIP addresses the 

adverse impacts of existing and certain new water-related activities on the Platte River 

target species and associated habitats, and provides ESA compliance for effects to the 

target species. The State of Wyoming is in compliance with its obligations under the 

PRRIP. The Wyoming State Engineer’s Office is responsible for determining if a water 

withdrawal is an existing or new water withdrawal and what level of withdrawal it 

constitutes. The level of withdrawal for a temporary industrial use would depend on the 

amount of depletion, and the existing conditions of the river at the time of the depletion. 

For federal actions and projects participating in the PRRIP, the PRRIP Final EIS 

(Bureau of Reclamation and USFWS 2006) and the June 16, 2006, programmatic 

Biological Opinion (USFWS 2006a) serve as the description of the environmental 

baseline and environmental consequences for the effects of the federal actions on the 

listed target species. Under the 2006 Programmatic Biological Opinion, any depletion 

from the Platte River system less than 0.1 acre-feet per year would result in a no effect

determination for the targeted species and whooping crane critical habitat, and would 

not require consultation with USFWS. Depletions greater than 0.1 acre-feet per year 

would require consultation, and would result in a may affect, likely to adversely affect

determination for the targeted species and a may affect, not likely to adversely affect

determination for designated whooping crane critical habitat (McKee 2012a). The 

USFWS has indicated that if all water can be drawn from depletions for which 

consultation has already taken place, this would not be considered an additional 

withdrawal and would result in no new effects to either the species or whooping crane 

designated critical habitat (McKee 2012a). However, in certain situations where the 

State Engineer’s Office determines that the new water withdrawal would constitute a 

change in use than the previous consultation addressed the no effect call may not be 

possible (McKee 2012b). In order to calculate the number of acre-feet per year, the 

total amount of water withdrawn is divided over the life of the Project, not necessarily 

over the number of years during which water would actually be withdrawn (Abbott 

2012). No depletion fee is associated with the PRRIP (McKee 2012a). None of the 

ESA-listed wildlife or plant species covered under the PRRIP or whooping crane critical 

habitat (Figure 3-2) are found in the Action Area (USFWS 1988a, 1990b, 1996a; Dryer 

and Sandvol 1993; CWS and USFWS 2007; 43 Federal Register 20938); however, they 

do occur downstream of the Action Area and an analysis of effects is required based on 

the PRRIP.
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Figure 3-2. Designated Whooping Crane Critical Habitat in relation to the Gateway West 

Project
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3.3 Mammals

Four federally threatened or endangered mammal species have the potential to occur in 

the vicinity of the Action Area, including the black-footed ferret, Canada lynx, grizzly 

bear, and Preble’s meadow jumping mouse. 

3.3.1 Black-Footed Ferret (10(j) Nonessential, experimental population)

Black-footed ferrets occur within the Action Area, where it comes near the 10(j) 

reintroduction area (i.e., the region where black-footed ferrets have been successfully 

reintroduced into the wild). The regulatory status of experimental nonessential would 

apply here and as will be discussed in detail below, the USFWS has agreed that wild 

ferret populations outside this area are not be expected. Again, efforts to save this 

species, including the reintroduction of black-footed ferrets into the wild (which includes 

the Shirley Basin 10(j) population within the Action Area) have been successful and the 

USFWS has determined that recovery and conservation will benefit from a recent 

decision to block-clear the entire rest of the State of Wyoming. The re-introduced 

populations are considered a nonessential experimental population and, by BLM policy, 

they are treated as an ESA proposed species (i.e., not protected under ESA from 

unintentional take). 

3.3.1.1 Status

The black-footed ferret was once described as “the rarest of North American mammals” 

(Whitaker 1980). This member of the weasel family was first designated as 

“endangered” by the Bureau of Sport Fisheries and Wildlife in 1966. It was then listed 

as “threatened with extinction” in March 1967, and its current status is endangered 

under the ESA. The USFWS in coordination with state wildlife agencies, have “blockcleared” the State of Wyoming, after determining that areas outside the reintroduction 

sites are no longer capable of supporting any wild, free-ranging black-footed ferrets. 

Block clearance means that activities within these areas that result in the removal of 

white-tailed or black-tailed prairie dogs or their habitat will no longer be required to meet 

the USFWS survey guidelines for black-footed ferrets, or undergo consultation under 

section 7 of the ESA. 

Black-footed ferrets were thought to be extinct until a small population was discovered 

in a prairie dog colony west of Meeteetse, Wyoming, in 1981. This population was 

decimated by outbreaks of canine distemper and sylvatic plague in 1986–1987 (WGFD 

2005). In 1991 through 2003, several nonessential experimental populations were 

established using reintroductions throughout the western and Midwestern U.S., the first 

of which was in the Action Area (i.e., in the Shirley Basin/Medicine Bow Management 

Area of southeastern Wyoming; 56 Federal Register 41473). This population is called

the Shirley Basin 10(j) population (hereafter referred to as “10(j)”). This re-introduced 

population is considered a nonessential experimental population and is treated as an 

ESA proposed species (i.e., not protected from unintentional take). 

3.3.1.2 Threats

Threats to black-footed ferrets can be evaluated by assessing threats to prairie dogs

(i.e., their primary prey source). Once abundant, prairie dogs have been the subject of

a deliberate eradication program across much of their range. In addition, much of the 
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open grassland habitat utilized by prairie dogs has been converted to agricultural uses; 

thereby resulting in habitat loss. Some estimates put the reduction in prairie dog 

populations since the 1900s to the present at 90 to 95 percent (USFWS 1988b). 

Strychnine and phostoxin gas have been used to control prairie dogs, and black-footed 

ferrets declined correspondingly (USFWS 1988b). 

In Wyoming, disease has been identified as the most influential variable affecting blackfooted ferret population dynamics (USFWS 1988b). Sylvatic plague is an exotic 

pathogen to which prairie dogs have no known natural immunity. The disease is highly 

infectious, and the death rate following infection is nearly 100 percent (Johnson et al. 

2011). Black-footed ferrets can contract sylvatic plague through bites from infected 

fleas, or by consuming infected prey (NatureServe 2011). Another disease that has 

been known to impact this species is canine distemper (USFWS 1988b).

3.3.1.3 Species Recovery

After the rapid decline of the remaining black-footed ferret population near Meeteetse, 

the 18 remaining individuals were captured and used as breeding stock for 

reintroductions throughout the Interior West and Mexico, which have been largely 

successful. A recovery plan was published for the black-footed ferret in 1988. The 

objective of this plan was to ensure the immediate survival of the black-footed ferret by 

a) increasing the captive population of breeding black-footed ferrets to 200 by 1991, b) 

establishing a wild population of 1,500 breeding adults in at least 10 populations by 

2014, and c) encouraging the widest possible distribution of reintroduced black-footed 

ferrets (USFWS 1988b). As of 2008, approximately 350 adults occurring in four 

successful reintroduced populations (i.e., Aubrey Valley, Cheyenne River Indian 

Reservation, Conata Basin, and Shirley Basin 10(j)); or approximately 23 percent of the 

goal of 1,500 free-ranging adults. There is an estimated 700 total individuals (when 

young are included) in these four reintroduced populations (USFWS 2008a).

3.3.1.4 Life History, Habitat Requirements, and Distribution

Black-footed ferrets are closely associated with prairie dogs, both as a prey item and 

because black-footed ferrets use prairie dog burrows for shelter and den sites (56 

Federal Register 41473); in fact, there have been no records of black-footed ferrets 

breeding outside of prairie dog colonies (56 Federal Register 41473). Black-footed 

ferrets hunt prairie dogs at night. Other animals taken include mice, gophers, and 

ground squirrels. Habitat requirements for the black-footed ferret are the same as for 

prairie dogs: open grasslands, steppe, and shrub steppe (NatureServe 2011).

The historical range is thought to be almost entirely coincident with that of the three 

North American prairie dog species, with an estimated 85 percent of ferrets occurring in

black-tailed prairie dog (Cynomys ludovicianus) habitat, 8 percent in Gunnison’s prairie 

dog (C. gunnisoni) habitat, and 7 percent in white-tailed prairie dog (C. leucurus) habitat

(USFWS 1988b, 2008). This area stretched from the great plains of Canada to the 

southwestern U.S., possibly into northern Mexico (USFWS 1988b). Historic 

distributions are thought to have encompassed 16 million acres in Wyoming; however, 

the current estimates place it at around 125,000 acres (USFWS 2000a). Currently, this 

species is found at 18 reintroduction sites in Montana, Wyoming, South Dakota, Utah, 

Colorado, Kansas, Arizona, New Mexico, and Mexico (USFWS 2008a).
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Reintroduction of black-footed ferrets in Wyoming (i.e., the 10(j) population) occurred at 

the 2,068 square mile white-tailed prairie dog complex in the Shirley Basin/Medicine 

Bow Management Area in 1991 (BLM 2005). Two hundred and twenty-eight ferrets 

were released over a four-year period at this site. As discussed above, this population

is considered a nonessential experimental population. The distribution of this 

population in relation to the Project is shown in Figure 3-3.

The 10(j) population discussed above is the only known population of black-footed 

ferrets in Wyoming and all other areas of the State have been block cleared, meaning 

that there is no requirement of survey or conduct Section 7 Consultation for these 

remaining areas.

3.3.1.5 Population Status

The global status of the black-footed ferret is critically Imperiled (NatureServe 2011). Of 

the 18 extant populations of black-footed ferret, 4 are considered successful, 2 

improving, 2 marginal, 2 unsuccessful, and 6 recent (initiated within the past 3 years). 

The Shirley Basin population (i.e., 10(j)) is currently classified as Successful, meaning it 

is self-sustaining, has at least 30 breeding adults, and can support translocations to 

other sites (USFWS 2008a). 

3.3.1.6 Critical Habitat

No critical habitat has been designated for the black-footed ferret.

3.3.1.7 Environmental Baseline

Species Presence

The only known black-footed ferrets in the vicinity of the Action Area are in the Shirley 

Basin in Wyoming (i.e., 10(j)), along Segment 1W and the eastern end of Segment 2

(Figure 3-3).

Habitat

The range of the 10(j) black-footed ferret population covers approximately 2,762,029

acres along Segments 1W and 2 of the Project, in southeastern Natrona County, 

northeastern Carbon County, and northwestern Albany County (Figure 3-3; WGFD 

2005). The Project would cross 6.3 miles of habitat within the predicted distribution of 

the 10(j)’s population (as defined by the USFWS within this species range; see Figure 

3-3); with 5.7 miles consisting of shrubland habitats, 0.5 mile consisting of grasslands, 

and the remaining length consisting of disturbed/developed areas or wetlands.
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Figure 3-3. Black-footed Ferret Range and Predicted Distribution
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Both white-tailed and black-tailed prairie dog colonies occur within the Action Area 

(Figure 3-3). Table 3-3 lists the number of white-tailed and black-tailed prairie dog 

colonies that would be crossed by the Project.

Table 3-3. Number of Black-Tailed and White-Tailed Prairie Dog Colonies Crossed by the 

Project

Segment Number Prairie Dog Colonies

Black-Tailed Prairie Dog Colonies

1W(a) 3

1W(c) 3

White-Tailed Prairie Dog Colonies

1W(a) 3

1W(c) 4

2 3

3 2

3A 4

4 8

Critical Habitat

No critical habitat has been designated for the black-footed ferret.

3.3.2 Canada Lynx (Threatened)

3.3.2.1 Status

The USFWS listed the Canada lynx as threatened in April 2000 (65 Federal Register

16052). Critical habitat for this species was designated on November 2006, and revised 

on February 2009 (71 Federal Register 66007; 74 Federal Register 8616).

3.3.2.2 Threats

The original reasons for listing lynx were loss, modification, or curtailment of its habitat 

or range, inadequacy of existing regulatory mechanisms, high-traffic-volume roads, and 

loss of habitat connectivity (65 Federal Register 16052). Habitat changes can 

negatively impact populations of snowshoe hare (Lepus americanus), the primary prey 

of lynx, and red squirrel (Tamiasciurus hudsonicus), a common alternate prey species. 

Clearcutting that decreases stem density, does not allow trees to reach a mature age, 

or does not allow the buildup of down wood is detrimental to lynx. Certain timber 

management practices can also lead to monotypic stands with sparse understories, 

which are not conducive to lynx or snowshoe hares. Fragmentation can also negatively 

impact lynx; although they readily cross clearcuts when traveling, too many clearcuts

can result in an insufficient amount of habitat for life processes.

Although overharvest was originally cited as a reason for lynx decline when the species 

was proposed for listing, new information at the time of listing showed that lynx naturally 

occur at low densities, especially at the southern extent of their range, and this does not 

necessarily indicate a declining population (65 Federal Register 16076). In the past 

decade, timber harvest within suitable lynx habitat has declined by approximately 80 

percent in the western U.S. 
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3.3.2.3 Species Recovery

Most states in which the Canada lynx occurs disallow or regulate the trapping of this 

species, and hunting laws were not a factor in the listing of lynx. Other regulatory 

mechanisms, however, are inadequate to protect this species, especially those that 

regulate changes to and destruction of habitat. Few habitat management goals and 

actions are specific to Canada lynx protection. At the time of listing, USFWS believed 

that there was a potential for adverse effects to lynx from goals and management 

actions outlined in federal land management plans. A substantial amount of forested 

habitat suitable for lynx is located on federal lands, and many planned actions, such as 

timber sales and road construction, could impact lynx. There is also a lack of sufficient 

habitat management regulations specifically aimed at lynx.

Although no recovery plan for Canada lynx exists, a recovery outline for this species in 

the contiguous U.S. has been drawn up (USFWS 2005), which lists a recovery strategy 

and goals, and areas which could be used as reintroduction sites. Areas of important 

habitat for Canada lynx, called lynx analysis units (LAUs), have been identified by the 

Forest Service and BLM in Wyoming, in units approximating the size of a typical home 

range for a female lynx. LAUs are considered important habitat for lynx, and are 

assumed to be occupied on National Forest lands (Forest Service 2007). There are 

about 555,604 acres of LAUs in total within Wyoming. No LAUs would be crossed by 

the Project, although there are two BLM LAUs located near Segment 4 in Wyoming, 

approximately 3 to 6 miles to the north (see Figure 3-4). 

3.3.2.4 Life History, Habitat Requirements, and Distribution

Lynx habitat is found generally at middle to upper elevations. Their habitat includes 

primarily cool, moist subalpine fir (Abies lasiocarpa) and Engelmann spruce (Picea 

engelmannii) forests, and moist lodgepole pine (Pinus contorta) forests. Cool, moist 

forests of Douglas-fir (Pseudotsuga menziesii), grand fir (Abies grandis), western larch 

(Larix occidentalis), and aspen (Populus tremuloides) contribute to lynx habitat where 

intermingled with, or adjacent to, Engelmann spruce or lodgepole pine. In extreme 

northern Idaho, cedar (Thuja spp.) hemlock (Tsuga spp.) habitat types may also be 

considered primary habitat (USFWS 2008b). In central Idaho, Douglas-fir on moist, 

high-elevation sites may be considered primary habitat as well (USFWS 2008b). Lynx 

tend to have very large home ranges, varying from 15,000 to 30,000 acres or 10 to 20 

square miles. Lynx are highly mobile, often making long-distance movements in excess 

of 60 miles. Studies have shown that they prefer contiguous forests and avoid large 

openings unless shrubs and trees provide enough hiding cover (Ruggiero et al. 1999). 

Lynx may also use lowland shrub habitats periodically, while dispersing between 

suitable high-elevation forest habitats, or while seeking shrub-dependent prey species 

(e.g., sage-grouse or jackrabbits [Lepus spp.]) while snowshoe hare populations are low

(Ruediger et al. 2000).
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Figure 3-4. Canada Lynx Linkage Areas, Critical Habitat, and Analysis Units in the Action 

Area for the Gateway West Transmission Line Project Route
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To protect the connectivity of this species’ habitats, an interagency/intergovernmental 

panel has designated lynx linkage habitat in Idaho, Montana, Utah, and Wyoming. 

These areas consist of regions that provide landscape connectivity between blocks of 

primary lynx habitat (Forest Service 2007). Linkage areas occur both within and 

between geographic areas where blocks of lynx habitat are separated by intervening 

areas of non-lynx habitat such as basins, valleys, or agricultural lands. 

Snowshoe hares are the primary prey of lynx, making up anywhere from 35 to 97 

percent of the diet (Ruggiero et al. 1999); therefore, any action that impacts snowshoe 

hares can have consequences to lynx. Other small mammal species, such as red 

squirrels, may be an important alternate prey, especially where hare populations are low 

(Ruggiero et al. 1999). 

3.3.2.5 Population Status

Although declines have occurred, this cat still apparently occurs throughout most of its 

historic range, and its global status is secure (NatureServe 2011). Current low numbers 

of Canada lynx in the southern part of their range may be natural, due to lower quality 

habitat at the periphery of their range (USFWS 2009, Murray 2008), and should not 

necessarily be interpreted as a downward trend in these areas. Due to the cyclic 

variability in lynx abundance (USFWS 2009), and limited monitoring in the southern 

extent of its range (USFWS 2009, Murray 2008), short-term recent trends are difficult to 

estimate. 

3.3.2.6 Critical Habitat

In November 2006 (71 Federal Register 66007), the USFWS designated critical habitat 

for the contiguous United States distinct population segment (DPS) of the Canada lynx: 

three units in Minnesota, Montana, and Washington. Lynx critical habitat was revised 

most recently in February 2009, and was expanded by approximately 23.7 million acres 

to comprise five units in Maine, Minnesota, Montana, Wyoming, Idaho, and Washington 

(74 Federal Register 8616). 

The Primary Constituent Element (PCE) is:

1. Boreal forest landscapes supporting a mosaic of differing successional forest 

stages and containing:

a. presence of snowshoe hares and their preferred habitat conditions, which 

include dense understories of young trees, shrubs, or overhanging boughs 

that protrude above the snow, and mature multistoried stands with conifer 

boughs touching the snow surface;

b. winter snow conditions that are generally deep and fluffy for extended periods 

of time;

c. sites for denning that have abundant coarse woody debris, such as downed 

trees and root wads; and

d. matrix habitat (e.g., hardwood forest, dry forest, non-forest, or other habitat 

types that do not support snowshoe hares) that occurs between patches of 

boreal forest in close juxtaposition (at the scale of a lynx home range) such 

that lynx are likely to travel through such habitat while accessing patches of 

boreal forest within a home range. 
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3.3.2.7 Environmental Baseline

Species Presence

In Idaho, lynx were likely never abundant, but were distributed sparsely throughout the 

northern part of the state. There are 35 verified records of lynx within the state between 

1960 and 1991. NFs in Idaho that have mapped primary and secondary lynx habitat 

and identified LAUs include the Sawtooth and Targhee, and the likelihood of lynx 

occupancy in both of these forests is unlikely and likely, respectively (USFWS 2008b). 

Most records in Wyoming, both historical and recent, are from the northwestern 

mountain ranges, and only 30 verified records exist since 1956 (65 Federal Register 

16052). Less than 100 individuals are currently estimated to live in each of Idaho and 

Wyoming (NatureServe 2011).

Habitat

The majority of the Action Area consists of unsuitable habitat for the Canada lynx, and 

no LAUs would be crossed, although two LAUs are only a few miles to the north of

Segment 4. 

Two linkage areas, through which lynx could conceivably travel, would be crossed by 

Segment 4 (Figure 3-4). The vegetation types within this general area consists

prominently of sagebrush habitats (66 percent of the area), grasslands (16 percent of 

the area), and agricultural fields (10 percent of the area).

Critical habitat

Critical Habitat Unit (CHU) 5 lies approximately 10 miles to the north of Segment 4 in 

Wyoming (Figure 3-4).

3.3.3 Grizzly Bear (Threatened)

3.3.3.1 Status

In July 1975, the grizzly bear was designated as threatened in the conterminous United 

States under the ESA. On March of 2007, the USFWS announced that the grizzly 

bear’s Yellowstone DPS had recovered and subsequently dropped their status as 

threatened under the ESA. In 2009, Montana District Court Judge Donald W. Molloy 

ruled that existing regulatory mechanisms outside the ESA were inadequate to protect 

the grizzly bears, and that the USFWS failed to adequately consider the impacts of 

global warming and other factors on food sources for the grizzly (especially whitebark 

pine), before delisting the Yellowstone DPS. Therefore, the Yellowstone DPS has been 

relisted as a threatened species under the ESA as of March 26, 2010 (75 Federal 

Register 14495). 

3.3.3.2 Threats

The main reason for the decline of grizzly bears in the continental U.S. is overhunting

(USFWS 1993, 72 Federal Register 14866). The primary threats to this species are

road and trail construction resulting in habitat modification and increased access by 

hunters, overhunting, population isolation, increasing presence of humans and livestock 

within its range, and impacts to whitebark pine (a food source for grizzly bears). Before 

European settlement, an estimated 50,000 grizzly bears lived in the western U.S. (62 
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Federal Register 35762); today those numbers are much less. The reported population 

size for the number of remaining wild bears varies. According to the USFWS website 

(updated December 19, 2012), approximately 1,400 to 1,700 bears are supported by 

remaining habitat in the lower 48 states (USFWS 2012c). The Interagency Grizzly Bear 

Committee, in contrast, reports 1,200 to 1,400 wild bears remaining, in an update 

written by the USFWS on October 10, 2012 (IGCB 2012). In September 2011, the 

USFWS published a 5-year review, which estimated that around 1,480 bears occur in 

the remaining habitat in Montana, Idaho, Wyoming, and Washington (USFWS 2011a). 

While it is known that the populations and distribution have increased since 1975, there 

is no published information for conclusive comparisons to historic levels (USFWS 

2011a).

3.3.3.3 Species Recovery

The Yellowstone DPS has increased from estimates as low as 136 individuals when this 

population was first listed in 1975, to more than 500 animals in 2006 (72 Federal 

Register 14866), with 582 individuals in 2010 (USFWS 2011a); population increases 

have occurred at a rate of 4 to 7 percent annually. The original recovery plan for this 

species was approved in 1982, and an updated plan was released in 1993. The 

recovery objective as stated in the plan revision is the delisting of each of the remaining 

grizzly bear populations as they achieve recovery targets. Actions needed are:

1. Minimize sources of human-bear conflict.

2. Limit habitat loss or degradation because of human actions such as road 

building, timber harvest, oil and gas exploration and development, mining, and 

recreation.

3. Improve habitat and/or security where applicable.

4. Understand the relationship between bear density and habitat value to better 

understand limiting factors.

5. Develop techniques to successfully move bears into areas where the populations 

are in need of augmentation.

6. Improve public relations and education to develop better support for and 

understanding of the species and to minimize adverse human actions.

7. Continue grizzly bear and habitat research to ensure adequate scientific 

knowledge is available on which to base management decisions (USFWS 1993).

The Primary Conservation Area (PCA) for the grizzly bear was established by the Final 

Conservation Strategy for the Grizzly Bear in the Greater Yellowstone Area (USFWS 

2007a), and the 1993 Grizzly Bear Recovery Plan (USFWS 1993). The PCA contains 

the minimum seasonal habitat components necessary to support grizzly bear 

populations. The PCA encompasses 9,209 square miles (5,893,760 acres) within three 

states: southern Idaho, southwest Montana, and northwest Wyoming (USFWS 2007a; 

Figure 3-5). In addition, the USFWS has designated the boundaries of the Yellowstone 

DPS and the acreage of suitable habitat within the DPS (USFWS 2007a; Figure 3-5). 
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Figure 3-5. Borders of the Primary Conservation Area, Suitable Habitat, and the Distinct 

Population Segment (DPS) of Yellowstone DPS Grizzly Bears, and the Gateway 

Transmission Line Route
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3.3.3.4 Life History, Habitat Requirements, and Distribution

Grizzly bears are habitat generalists; however, they are found most often in 

mountainous habitats, away from human developments. Forested areas interspersed 

with openings are often used, and one study found that only 1 percent of bears were 

found in dense forest more than a kilometer from an opening (Blanchard 1978, in 

USFWS 1993). The primary factors that determine the suitability and carrying capacity 

of habitat are overall habitat productivity, availability of food, and the level and types of 

human activities present. Food types utilized by the Yellowstone DPS grizzly bears 

vary by season, and can include ungulates, spawning cutthroat trout (Oncorhynchus 

clarki), whitebark pine seeds, and army cutworm moths (Euxoa auxiliaris; USFWS 

2007a). In fact, impacts to the whitebark pine due to global warming and infestation by 

pine beetles was one of the primary reasons for the relisting the Yellowstone DPS. 

Grizzly bears are solitary, with large home ranges; the density of grizzly bears in the 

Yellowstone Grizzly Bear Ecosystem in 1974 was estimated at 1 bear per 34 square 

miles (USFWS 1993). 

At the time of listing, grizzly bears in the continental U.S. existed in only three locations: 

the Selway-Bitterroot ecosystem (in Idaho and Montana), the Bob Marshall ecosystem 

(mostly in Montana), and the Yellowstone ecosystem (mostly in Wyoming). Their 

current distribution covers five geographic areas: the Cabinet/Yaak ecosystem 

(Montana and Idaho), the Selkirk ecosystem (Idaho and Washington), the North 

Cascades ecosystem (Washington), the Northern Continental Divide ecosystem 

(Montana), and the Yellowstone ecosystem (mostly Wyoming) in addition to a Nonessential experimental population in the Bitterroot area of Idaho and Montana (USFWS 

2011a).

3.3.3.5 Population Status

Recent estimates have shown that the number of grizzly bears in the Greater 

Yellowstone Area is over 500 bears, satisfying a recovery goal listed in the grizzly bear 

conservation strategy (USFWS 2007a). The success of recovery actions aimed at this 

DPS was sufficient to warrant delisting of this population (although the delisting was 

later overturned).

3.3.3.6 Critical Habitat

Critical habitat for grizzly bears was proposed in 1976; however, none has been 

designated.

3.3.3.7 Environmental Baseline

Species Presence

The closest known grizzly bear occurrence is located about 100 miles north of Segment 

4 (72 Federal Register 14866). The Project is not located within the extent of the PCA, 

or through areas identified by the USFWS as suitable grizzly bear habitats; however, 

Segments 3 and 4 would pass through the southernmost extent of the Yellowstone 

DPS for a total of 163.5 miles. Note that grizzly bears only occupy 68 percent of 

suitable habitats located within the DPS boundaries (indicating that bears are not 

located throughout the DPS); however, they may soon occupy the remainder of 
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available suitable habitat (USFWS 2007a). The Project’s crossing of the Yellowstone 

DPS would occur along the southernmost edge of the DPS boundary (outside of the 

PCA or suitable habitat), adjacent to Highway 80, Highway 30, and the town of 

Kemmerer (Figure 3-5). As a result, it is highly unlikely that grizzly bears would utilize 

the habitats crossed by the Project.

Habitat

The closest suitable habitat for grizzly bears to the Action Area is approximately 100 

miles to the north of Segment 4 (72 Federal Register 14866). The portion of the grizzly 

bear DPS crossed by the Project is located adjacent to Highway 80, Highway 30, and 

the town of Kemmerer, indicating that this area is highly disturbed by human 

developments and activities.

Critical habitat

No critical habitat has been designated for this species.

3.3.4 Preble’s Meadow Jumping Mouse (Threatened)

3.3.4.1 Status

The Preble’s meadow jumping mouse was listed as threatened throughout its range in 

May 1998 (63 Federal Register 26517). On February 2, 2005, the USFWS issued a 12-

month finding on a petition to delist the Preble's meadow jumping mouse and proposed 

to remove the mouse from the federal list of threatened and endangered species, due to 

their finding that the Preble’s meadow jumping mouse is not a discrete taxonomic entity 

and does not meet the definition of a subspecies (70 Federal Register 5404). In July 

2008, the Preble’s meadow jumping mouse was determined to be a valid subspecies 

and it maintained its threatened status in Colorado, but individuals in Wyoming were no 

longer listed and critical habitat in Wyoming was eliminated (73 Federal Register

39790). In August 2011, however, ESA protections for this species in Wyoming were 

reinstated, though critical habitat in Wyoming was not (76 Federal Register 47490).

3.3.4.2 Threats

The primary threat to the Preble’s meadow jumping mouse is serious declines of habitat 

quantity and quality and fragmentation of habitat, principally through conversion of 

prairie habitat containing well developed riparian areas to agricultural and residential 

developments (73 Federal Register 39790). Changes in stream flow regimes due to 

water developments, diversions, and flood control have decreased the vegetative cover 

these mice need for hiding, nests, food, and hibernation (73 Federal Register 39790). 

Road construction, bank stabilization, intense grazing, rock and sand extraction, 

invasive weeds, and fire have also been identified as threats. All threats to the Preble’s 

meadow jumping mouse are expected to be less severe in Wyoming than in Colorado 

due to Wyoming having a smaller human population (73 Federal Register 39790). 

There are also few regulatory mechanisms in place that would protect Preble’s meadow 

jumping mouse if ESA protections were removed (73 Federal Register 39790). Threats 

to this species in the North Platte River are believed to be less severe than those in the 

South Platte and Arkansas Rivers (USFWS 2003).
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3.3.4.3 Species Recovery

In 2003, a Preble’s meadow jumping mouse recovery team released a list of recovery 

recommendations for the species (USFWS 2003). The recovery objective for these 

recommendations is the delisting of this species. The recovery criteria for delisting are:

1. Document and maintain wild, self-sustaining Preble’s meadow jumping mouse 

populations.

2. Protect and manage habitat of Preble’s meadow jumping mouse populations.

3. Abate threats to Preble’s meadow jumping mouse populations.

4. Develop and implement a long-term management plan and cooperative 

agreement prior to delisting (USFWS 2003).

In 2009, the recovery team reconvened and is working toward development of a final 

recovery plan.

3.3.4.4 Life History, Habitat Requirements, and Distribution

Preble’s meadow jumping mouse habitat consists of dense, well-developed wetland and 

riparian areas with dense vegetation, as well as the adjoining uplands containing 

undisturbed shrub cover up to 328 feet beyond the 100-year floodplain. Upland areas 

are used for hibernation, foraging, and to escape flooding. They are found between 

4,650 and 7,600 feet elevation (73 Federal Register 39790). Hibernation occurs 

underground or beneath logs or other similar shelters from mid-October through early 

May (USFWS 2003). Studies show that the Preble’s meadow jumping mouse is 

capable of traveling more than 0.5 mile in a single night. The diet of these rodents 

includes arthropods, fungus, moss, pollen, and a wide variety of plants, especially 

willow (Salix spp.; USFWS 2003). The lifespan of these mice is short. Many animals 

prey upon them, including garter snakes (Thamnophis spp.), prairie rattlesnakes 

(Crotalus viridus), bullfrogs (Lithobates catesbeianus), foxes (Vulpes vulpes and/or

Urocyon cinereoargenteus), house cats, long-tailed weasels (Mustela frenata), and redtailed hawks (Buteo jamaicensis; USFWS 2003).

They are found from the eastern flank of the Laramie Mountains and the Laramie Plains 

in southeastern Wyoming south along the eastern flank of the Front Range in Colorado 

and into the headwaters of the Arkansas River basin near Colorado Springs, Colorado 

(USFWS 2003). The northern extent of the currently known distribution of Preble’s 

meadow jumping mouse is the North Platte River at Douglas, Wyoming, and the 

southern extent is Colorado Springs, Colorado (73 Federal Register 39790). The extent 

of their known distribution is shown in Figure 3-6.

3.3.4.5 Population Status

No reliable abundance estimates for the Preble’s meadow jumping mouse exist, and 

population trends and density are not well known (73 Federal Register 39790). Still, 

knowledge about the distribution of this species has increased dramatically since the 

time of original listing due to increased trapping and survey efforts. These efforts have 

resulted in an expansion of the known range of these mice, especially in Wyoming (73 

Federal Register 39790), and further studies are needed. The global status of the 

Preble’s meadow jumping mouse is Imperiled (NatureServe 2011).
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Figure 3-6. Preble’s Meadow Jumping Mouse Critical Habitat in Relation to the Gateway 

West Transmission Line Project Location 
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3.3.4.6 Critical Habitat

Critical habitat has been designated for Preble’s meadow jumping mouse in Colorado, 

totaling eight habitat units along approximately 411 miles of rivers and streams, totaling 

34,935 acres (75 Federal Register 78430); however, no critical habitat has been 

designated in Wyoming.

3.3.4.7 Environmental Baseline

Species Presence

In the North Platte River Basin these mice have been confirmed in Converse, Platte, 

Albany, Goshen, and Laramie Counties (73 Federal Register 39790). However, 

knowledge about the distribution of this species has increased dramatically since the 

time of original listing due to increased trapping and survey efforts; these efforts have 

resulted in an expansion of the known range of these mice, especially in Wyoming (73 

Federal Register 39790), and further studies are needed.

The closest known occurrence of a Preble’s meadow jumping mouse to the Analysis 

Area was one female from 1991 that was located approximately 3.7 miles east of 

Segment 1Wc; however, it is not a confirmed record (WYNDD 2010).

Habitat

The Preble’s meadow jumping mouse could utilize the portion of the Project that 

crosses through wetland and riparian areas within the eastern portion of the Wyoming 

segments of the Project (i.e., Segments 1W and 2), as well as 100-year floodplain and

upland areas within 328 feet of the 100-year floodplain; however, of the counties 

crossed by the Project, they have only been documented to occur within Converse 

County. Wetlands within this portion of the Action Area vary by type, and consist of 

approximately 2 percent of emergent wetlands, 4 percent of forested/shrub wetlands, 

and 94 percent open waters (e.g., rivers and ponds).

Critical Habitat

The closest critical habitat to the Action Area is the North Fork Cache La Poudre River 

Unit in Larimer County, Colorado, approximately 100 miles southeast of Segment 2

(Figure 3-6; 75 Federal Register 78430). 

3.4 Fish

There are no threatened or endangered fish species potentially occur in the vicinity of 

the Action Area; however, bull trout designated critical habitat does occur in the Action 

Area.

3.4.1 Bull Trout (Threatened)

The Columbia River DPS of bull trout was listed as threatened in June 1998 (63 Federal 

Register 31647). Likely once widespread throughout the Pacific Northwest, numbers 

and distribution of bull trout have declined dramatically. In southern Idaho, bull trout 

subpopulations are generally low in abundance, fragmented, and isolated. The primary 

reasons for listing were habitat fragmentation and degradation. Installations of dams 
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have blocked passage for bull trout, isolating populations, and have also created 

reservoirs, which provide suboptimal habitat for this species (USFWS 2002a). Irrigation 

diversions and roads have also created impassable barriers. Mining, timber harvest, 

road construction, grazing, and other land management activities have degraded 

habitat. Non-native and hatchery-raised trout cause problems for bull trout through 

hybridization, disease transmission, and predation (USFWS 2002a). Today, the closest 

bull trout to the Action Area are in the Boise River watershed, upstream of the 

impassable Lucky Peak Dam, just southeast of Boise, approximately 10 miles northeast 

of Segment 8. This area is outside of the Action Area. 

The Project crosses the Bruneau River, which has the potential to be used for foraging, 

migration, and overwintering by the Jarbidge River DPS of bull trout (USFWS 2004). 

The Jarbidge River DPS of bull trout which was listed as threatened in 1999 (64 Federal 

Register 17110). The Bruneau River is unsuitable for bull trout during several months of 

the year due to naturally occurring warm summer water temperatures. Adequate 

surveys to document species presence in the Bruneau River have not been conducted 

during the periods when water temperatures are favorable for bull trout (mid-October 

through mid-June). However, fluvial bull trout have been documented to use the 

mainstem Jarbidge River; and there are no known physical barriers preventing fish 

movement between the Jarbidge and Bruneau Rivers. Once in the Bruneau River, fish 

passage is physically unrestricted for approximately 40 miles downstream to Buckaroo 

Ditch Dam at Hot Springs, Idaho. At this time, bull trout have not been documented to 

use the Bruneau River, although the Bruneau River has been designated as bull trout 

critical habitat. Use of the Bruneau River by bull trout remains unconfirmed; therefore, 

the Project is not expected to impact bull trout, and the species will not be analyzed 

further in this document, except to discuss potential impacts to their critical habitat.

3.4.1.1 Critical Habitat

Critical habitat for bull trout was designated in October 2004 (69 Federal Register

59996), and revised in October 2010 (75 Federal Register 63898) to include a total of 

19,729 miles of streams and 488,252 acres of reservoirs or lakes. The extent of critical 

habitat along streams is the bankfull elevation of the stream. PCEs for bull trout critical 

habitat are:

1. Springs, seeps, groundwater sources, and subsurface water connectivity 

(hyporheic flows) to contribute to water quality and quantity and provide thermal 

refugia.

2. Migration habitats with minimal physical, biological, or water quality impediments 

between spawning, rearing, overwintering, and freshwater and marine foraging 

habitats, including but not limited to permanent, partial, intermittent, or seasonal 

barriers.

3. An abundant food base, including terrestrial organisms of riparian origin, aquatic 

macroinvertebrates, and forage fish.

4. Complex river, stream, lake, reservoir, and marine shoreline aquatic 

environments, and processes that establish and maintain these aquatic 
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environments, with feature such as large wood, side channels, pools, undercut 

banks, and unembedded substrates, to provide a variety of depths, gradients, 

velocities, and structure.

5. Water temperatures ranging from 36 to 59 degrees Fahrenheit (°F), with 

adequate thermal refugia available for temperatures that exceed the upper end of 

this range. Specific temperatures within this range will depend on bull trout lifehistory stage and form; geography; elevation; diurnal and seasonal variation; 

shading, such as that provided by riparian habitat; streamflow; and local 

groundwater influence.

6. In spawning and rearing areas, substrate of sufficient amount, size, and 

composition to ensure success of egg and embryo overwinter survival, fry 

emergence, and young-of-the-year and juvenile survival. A minimal amount of 

fine sediment, generally ranging in size from silt to coarse sand, embedded in 

large substrates, is characteristic of these conditions. The size and amounts of 

fine sediment suitable to bull trout will likely vary from system to system.

7. A natural hydrograph, including peak, high, low, and base flows within historic 

and seasonal ranges or, if flows are controlled, minimal flow departure from a 

natural hydrograph.

8. Sufficient water quality and quantity such that normal reproduction, growth, and 

survival are not inhibited.

9. Sufficiently low levels of occurrence of nonnative predatory (e.g., lake trout, 

walleye, northern pike, smallmouth bass); interbreeding (e.g., brook trout); or 

competing (e.g., brown trout) species that, if present, are adequately temporally 

and spatially isolated from bull trout.

Segment 9 of the transmission line would span a portion of the Jarbidge River CHU 

along the Bruneau River, approximately 10 miles south of C.J. Strike Reservoir; 

however, no road crossings would be located within bull trout critical habitat. 

The Jarbidge River CHU encompasses the Jarbidge and Bruneau River basins, which 

drain into the Snake River within C.J. Strike Reservoir upstream of Grand View, Idaho. 

The Jarbidge River CHU is located approximately 70 miles north of Elko within Owyhee 

County in southwestern Idaho and Elko County in northeastern Nevada, and includes 

152 miles of streams designated as critical habitat. The Jarbidge River CHU contains 

six local populations of resident and migratory bull trout and provides spawning, rearing, 

foraging, migratory, connecting, and overwintering habitat. Because fluvial bull trout 

have been documented to use the mainstem Jarbidge River, bull trout may also use the 

Bruneau River for foraging, migration, and overwintering habitat. However, as 

described above, bull trout are not known to occur in the Bruneau River, including the 

stretch of critical habitat along the Bruneau River that would be crossed by the Project 

(64 Federal Register 17110; USFWS 2004). 
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3.5 Invertebrates

Four federally threatened or endangered invertebrates could potentially occur in the 

vicinity of the Action Area. These include the Banbury Springs limpet, Bliss Rapids 

snail, Bruneau hot springsnail, and the Snake River physa snail.

3.5.1 Banbury Springs Limpet (Endangered)

3.5.1.1 Status

The Banbury Springs limpet was listed as endangered in January 1992 (57 Federal 

Register 59244). 

3.5.1.2 Threats

The principal threat to the Banbury Springs limpet is habitat modification, specifically 

hydrologic flow patterns, deteriorating water quality, and water diversion (USFWS 

2006b). Dams along the Snake River may have altered hydrologic flow patterns and 

decreased flooding, isolating the four known locations where this snail can be found 

from each other; individuals may have historically been able to move among locations 

during flooding (USFWS 2006b). Dams also slow water velocity, raise water 

temperature, and decrease dissolved oxygen in the water (USFWS 2006b). Output at 

each of the natural springs where this species is found has been reduced by water use 

for agricultural irrigation.

3.5.1.3 Species Recovery

A recovery plan for five federally listed snails found along the Snake River between C.J. 

Strike Reservoir and American Falls Dam, including the Banbury Springs limpet, was 

released in 1995 (USFWS 1995a). The short-term recovery objective of this recovery 

plan was to protect known live colonies of the five snails by eliminating or reducing 

known threats, and the long-term objective was to restore viable, self-reproducing 

colonies of the five snails within specific geographic ranges to the point that they are 

delisted (USFWS 1995a). To assist in these recovery goals, a recovery area for the 

Banbury Springs limpet was established, which includes tributary cold-water spring 

complexes to the Snake River between river miles (RM) 584.8 and 589.3 (Figure 3-7; 

USFWS 1995a). The 5-year review for this species found that the factors originally 

threatening this species with extinction still remain (USFWS 2006b). 

3.5.1.4 Life History, Habitat Requirements, and Distribution

This snail is only known to occur at coldwater (59 to 61°F) spring complexes in riffles 

and margins of rapids with well oxygenated water of good quality (USFWS 1995a). 

They are most often found on smooth basalt at 12 to 30 inches depth. They are 

intolerant of pollution (USFWS 1995a).

This species is known from only four coldwater springs along the middle Snake River: 

Thousand Springs, Box Canyon Springs, Banbury Springs, and Briggs Springs (USFWS 

2006b). These four locations are isolated from each other, with distances between 

them of 1 to 4 miles (USFWS 2006b).
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Figure 3-7. Distribution and Recovery Areas for Banbury Springs Limpet, Bliss Rapids 

Snail, Bruneau Hot Springsnail, and Snake River Physa Snail
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3.5.1.5 Population Status

Population size and trends for this snail are largely uncertain due to lack of data. Lack 

of long-term surveys with consistent methodology across years hinders knowledge of 

abundance and trends. During surveys in 1992, the number of individuals at Thousand 

Springs was estimated at between 600 and 1,200. The species has been described as 

common at Briggs Springs, with 4.7 individuals per cobble in 2006, and “rare” at Box 

Canyon Springs in 1994 (USFWS 2006b). The Banbury Springs limpet is considered to 

be critically imperiled (NatureServe 2011).

3.5.1.6 Critical Habitat

No critical habitat has been designated for the Banbury Springs limpet.

3.5.1.7 Environmental Baseline

Species Presence

The only known locations for the Banbury Springs limpet are at springs along a 7-mile 

stretch of the Snake River. This stretch of river is within the Action Area, between 

Segments 8 and 9 (Figure 3-7).

Habitat

Habitat for this species has been seriously altered, and the only known suitable habitat 

in the Action Area to which individuals could conceivably migrate are the four springs 

where the Banbury Springs limpet is extant. This portion of the Snake River in Idaho is 

heavily influenced by human use. Groundwater pumping has resulted in declines of 

spring discharges over the past 60 years. In addition, both fertilizers and animal wastes 

contribute to groundwater nitrates and these contaminants have been documented to 

reach toxic levels (Tesch et al. 2003; Neely 2005). Springs provide an important 

contribution in maintaining/improving water quality in the Snake River and adjacent cold 

water springs within the action area and as such, impacts from over-pumping of the 

aquifer or groundwater contamination can be expected to adversely affect habitats 

occupied by listed Snake River snails. Agricultural uses also impact the water quality of 

surface water sources and conveyances (e.g., streams, irrigation return canals) (Clark 

et al. 1998 ). In addition, aquaculture facilities in the middle Snake River region 

contributes wastes from fish food, fish metabolism, and processing (Clark et al. 1998) 

as well residual antibiotic and antiseptic compounds to the Snake River (EPA 2002 ). 

The lethal limits of these threats (e.g., aquifer depletion and spring discharge, 

increasing contaminant risks from growing agricultural industries) on listed Snake River 

snails are not known, but it is likely that continuing degradation and over-consumption of 

water resources (due to increasing human use) will degrade snail habitat and place 

listed Snake River snails at greater risk over time. In addition, listed Snake River snails 

may also be threatened by future introduction of invasive species. 

Critical Habitat

No critical habitat has been designated for the Banbury Springs limpet.
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3.5.2 Bliss Rapids Snail (Threatened)

3.5.2.1 Status

The Bliss Rapids snail was listed as threatened in December 1992 (57 Federal Register

59244). In June 2007, it was found that a petition to delist the species may be

warranted and that a status review of the Bliss Rapids snail would be conducted (72 

Federal Register 31250); however, the USFWS determined in September 2009 that the 

Bliss Rapids snail is likely to become endangered within the foreseeable future (74 

Federal Register 47536), and it retained its threatened status.

3.5.2.2 Threats

Construction of dams along the mainstem Snake River likely eliminated habitat between 

suitable sites, isolating populations by preventing movement of individuals between 

them (USFWS 1995a). Changing water levels resulting from operations of hydroelectric 

dams also decrease suitable habitat for this snail by dewatering shallow shoreline 

habitats or by flooding habitat with warm, lentic water. Dams also increase siltation in 

snail habitat. Declining water quality due to agriculture, feedlots, dairies, hatcheries, 

and municipal sewage also negatively impacts this sensitive species. Diversion of 

water from springs and from the Snake River Plain aquifer limits the amount of recharge 

of clean water which these snails require. The New Zealand mudsnail (Potamopyrgus 

antipodarum) is an exotic species widely distributed throughout the middle Snake River 

and experiencing explosive growth. Although this invasive snail is not currently 

abundant in habitats used by the Bliss Rapids snail, this adaptable species can tolerate 

a wide range of water and habitat conditions and has the potential to compete directly 

with the Bliss Rapids snail for the limited areas of appropriate habitat for this species. In 

addition, few regulatory mechanisms exist to protect the Bliss Rapids snail.

3.5.2.3 Species Recovery

A recovery plan for five federally listed snails found along the Snake River between C.J. 

Strike Reservoir and American Falls Dam, including the Bliss Rapids snail, was 

released in 1995 (USFWS 1995a). The short-term recovery objective of this recovery 

plan was to protect known live colonies of the five snails covered by the plan by 

eliminating or reducing known threats, and the long-term objective was to restore viable, 

self-reproducing colonies of the five snails within specific geographic ranges to the point 

that they are delisted (USFWS 1995a). The recovery plan established a recovery area 

for the Bliss Rapids snail. This is located along the mainstem Snake River and tributary 

coldwater spring complexes from RM 547 to 585 (Figure 3-7). 

By 2009, the range of the Bliss Rapids snail had not changed since the time of listing, 

and increased sampling effort has documented this species at many more locations 

within this range than were originally known.

3.5.2.4 Life History, Habitat Requirements, and Distribution

The Bliss Rapids snail is found in two different habitat types: springs and rivers. Spring 

habitat is coldwater springs and spring-fed tributaries to the Snake River; river habitat is 

in the Snake River. Spring habitat is more productive, containing higher density and 

abundance of snails, than river habitat (74 Federal Register 47536). Cold (59 to 61°F), 
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moving water of low turbidity with clean, cobble or boulder substrate free of attached 

plants is preferred by this snail (USFWS 1995a). It is not found in lentic habitats or with 

fine sediment substrate (74 Federal Register 47536). Diet consists primarily of epilithic 

periphyton, although detritus, bacteria, and protozoa are also consumed. Individuals 

hatch, reproduce, and die in a single year, and may reproduce more than once (74 

Federal Register 47536). 

The historical distribution of the Bliss Rapids snail was along the middle mainstem 

Snake River from Indian Cove Bridge and Twin Falls. River habitat sites containing this 

species are currently found at scattered locations along a 22-mile stretch of the 

mainstem Snake River between King Hill and Salmon Falls Creek, notably in the 

Hagerman reach and the tailwaters of Bliss and Lower Salmon Dams. Spring habitat 

sites are at several unpolluted springs in the Hagerman Valley, including Thousand 

Springs, Banbury Springs, Box Canyon Springs, and Niagara Springs (USFWS 1995a).

3.5.2.5 Population Status

This species can be locally abundant at areas where habitat is suitable. However, the 

Bliss Rapids snail has declined or been eliminated from several known sites (USFWS 

1995a), and all known threats to this species are still present throughout its range and 

continue to exert negative pressure on all populations (74 Federal Register 47536). 

Although the known range of this species has expanded, this is likely due to increased 

survey pressure since its listing rather than actual increases in range and abundance. 

The Bliss Rapids snail is considered to be critically imperiled (NatureServe 2011).

3.5.2.6 Critical Habitat

Critical habitat has not been designated for the Bliss Rapids snail.

3.5.2.7 Environmental Baseline

Species Presence

The stretch of the Snake River along which the Bliss Rapids snail is found is within the 

Action Area, between Segments 8 and 9 (Figure 3-7).

Habitat

All known remaining suitable habitat for this species is found within the Action Area, 

between Segments 8 and 9. This portion of the Snake River in Idaho is heavily 

influenced by human use. Groundwater pumping has resulted in declines of spring 

discharges over the past 60 years. In addition, both fertilizers and animal wastes 

contribute to groundwater nitrates and these contaminants have been documented to 

reach toxic levels (Tesch et al. 2003; Neely 2005). Springs provide an important 

contribution in maintaining/improving water quality in the Snake River and adjacent cold 

water springs within the action area and as such, impacts from over-pumping of the

aquifer or groundwater contamination can be expected to adversely affect habitats 

occupied by listed Snake River snails. Agricultural uses also impact the water quality of 

surface water sources and conveyances (e.g., streams, irrigation return canals; Clark et 

al. 1998). In addition, aquaculture facilities in the middle Snake River region contributes 

wastes from fish food, fish metabolism, and processing (Clark et al. 1998) as well 
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residual antibiotic and antiseptic compounds to the Snake River (EPA 2002). The lethal 

limits of these threats (e.g., aquifer depletion and spring discharge, increasing 

contaminant risks from growing agricultural industries) on listed Snake River snails are 

not known, but it is likely that continuing degradation and over-consumption of water 

resources (due to increasing human use) will degrade snail habitat and place listed 

Snake River snails at greater risk over time. In addition, listed Snake River snails may 

also be threatened by future introduction of invasive species. 

Critical habitat

Critical habitat has not been designated for the Bliss Rapids snail.

3.5.3 Bruneau Hot Springsnail (Endangered)

3.5.3.1 Status

The Bruneau hot springsnail was listed as endangered in January 1993 (58 Federal 

Register 5938). The USFWS was ordered to reconsider its determination by the courts, 

and reconfirmed this species’ endangered status in June 1998 (63 Federal Register

32981). 

3.5.3.2 Threats

The main threat to the Bruneau hot springsnail is loss of geothermal habitat and 

reduced water levels due to groundwater withdrawal, mostly for agriculture. In 1993, 50 

private wells were documented within 7.5 miles of the Indian Bathtub site using 

geothermal water for irrigation (USFWS 2002b). In 1991, it was determined that the 

quantity of water pumped from the underlying aquifer where Bruneau hot springsnails 

are found exceeded natural recharge (58 Federal Register 5938). Some habitat is 

rendered unsuitable due to increased sedimentation. The ability of Bruneau hot 

springsnails to disperse to unoccupied suitable habitat is very low due to the limited 

mobility of this species and its intolerance for intervening habitat that is unsuitable due 

to low temperature. Bruneau hot springsnails are also preyed upon by some species of 

introduced fish. There have been reports of direct trampling of individuals by livestock. 

In addition, the small, isolated nature of most populations makes them vulnerable to 

stochastic catastrophic events.

3.5.3.3 Species Recovery

A recovery plan for Bruneau hot springsnail was released in 2002. The stated recovery 

goal for this species is its delisting. Actions needed to reach this goal listed in the 

recovery plan include the following (USFWS 2002b):

1. Implementing conservation measures to increase water levels in the regional 

geothermal aquifer,

2. Implement a groundwater monitoring program to assess changes in the 

geothermal aquifer,

3. Implement a monitoring program to assess the survival and recovery of the 

Bruneau hot springsnail and its habitat,

4. Develop and implement a habitat restoration program, and
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5. Develop and implement a control program for non-native fish that prey upon the 

Bruneau hot springsnail.

An action plan published for this species describes these and other actions in further 

detail. The recovery area for this species is along the Bruneau River and a small 

portion of adjacent lower Hot Creek (Figure 3-7; USFWS 2002b). The 5-year review for 

this species found that the factors originally threatening this species with extinction still 

remain (USFWS 2007d). 

3.5.3.4 Life History, Habitat Requirements, and Distribution

Habitat is flowing thermal springs and seeps between 60 and 98°F, with highest snail 

densities recorded above 73°F (USFWS 2002b). Snails are found where these plumes 

of hot water enter the main river channel. Individuals use various exposed substrates 

such as rock, gravel, sand, mud, and algal film. Bruneau hot springsnails feed 

opportunistically on algae; species consumed are proportional to those present in the 

area (58 Federal Register 5938). Sexual maturity is reached at two months, and 

reproduction can occur throughout the year. Snails deposit their eggs on a hard 

surface, including occasionally on another snail’s shell. 

This species is found only along a 5-mile stretch of the Bruneau River in Owyhee 

County, southwest Idaho, in the springflows of Hot Creek and many small, flowing 

thermal springs and seeps along the Bruneau River. The 5-mile stretch reaches from 

about 2.5 miles below Hot Creek to 2.5 miles above Hot Creek (58 Federal Register

5938).

3.5.3.5 Population Status

The population of Bruneau hot springsnails declined by an estimated 50 percent 

between 1982 and 1991, corresponding with a 32 percent decrease in the number of 

geothermal springs and seeps occupied by this species between 1991 and 1998. The 

species has been eliminated at some local areas such as the Indian Bathtub springs 

due to water removal for agriculture and drought conditions. Groundwater withdrawals 

from the aquifer underlying the range of Bruneau hot springsnail decreased between 

1983 and 1993 due to the withdrawal of lands from agriculture through the Conservation 

Reserve Program; however, water levels in the aquifer continue to decline (58 Federal 

Register 5938). The Bruneau hot springsnail is considered to be critically imperiled 

(NatureServe 2011).

3.5.3.6 Critical Habitat

The USFWS determined that the designation of critical habitat for Bruneau hot 

springsnail is not prudent due to the very limited areas where this species is found. If 

critical habitat were designated, there would be the risk for vandalism and further losses 

to this species (58 Federal Register 5938).

3.5.3.7 Environmental Baseline

Species Presence

The stretch of the Bruneau River that comprises the entire known range of this species 

is approximately 5 miles south of Segment 9 (Figure 3-7).
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Habitat

The stretch of the Bruneau River that contains all known remaining suitable habitat for 

the Bruneau hot springsnail is approximately 5 miles south of Segment 9.

Critical Habitat

No critical habitat has been designated for the Bruneau hot springsnail.

3.5.4 Snake River Physa Snail (Endangered)

3.5.4.1 Status

The Snake River physa snail was listed as endangered in December 1992 (57 Federal 

Register 59244). 

3.5.4.2 Threats

Construction of dams along the mainstem Snake River likely eliminated habitat between 

suitable sites, isolating populations by preventing movement of individuals between 

them (USFWS 1995a). Changes in river flow resulting from operations of hydroelectric 

dams also decrease suitable habitat for this snail by flooding cold rapids with warm, 

lentic water. Dams also increase siltation in snail habitat. Declining water quality due to 

agriculture, feedlots, dairies, hatcheries, and municipal sewage further negatively 

impacts this sensitive species. Diversion of water from springs and from the Snake 

River Plain aquifer limits the amount of recharge of clean water, which these snails 

require. The New Zealand mudsnail (Potamopyrgus antipodarum) is an exotic species 

widely distributed throughout the middle Snake River and experiencing explosive 

growth. Although this invasive snail is not currently abundant in habitats used by the 

Snake River physa snail, this adaptable species can tolerate a wide range of water and 

habitat conditions and directly competes for habitat with the Snake River physa snail. In 

addition, few regulatory mechanisms exist to protect the Snake River physa snail.

3.5.4.3 Species Recovery

A recovery plan for five federally listed snails found along the Snake River between C.J. 

Strike Reservoir and American Falls Dam, including the Bliss Rapids snail, was 

released in 1995 (USFWS 1995a). The short-term recovery objective of this recovery 

plan was to protect known live colonies of the five snails covered by the plan by 

eliminating or reducing known threats, and the long-term objective was to restore viable, 

self-reproducing colonies of the five snails within specific geographic ranges to the point 

that they are delisted (USFWS 1995a). The recovery plan established a recovery area 

for the Snake River physa snail: the mainstem Snake River from RMs 553 to 675 

(Figure 3-7; USFWS 1995a).

3.5.4.4 Life History, Habitat Requirements, and Distribution

Habitat requirements for the Snake River physa snail are cold, unpolluted, welloxygenated flowing water with low turbidity. These snails use the undersides of gravelto-boulder size substrate in swift currents in the mainstem Snake River, sometimes in 

the deepest parts of the river at the margins of rapids (USFWS 1995a). It has been 

hypothesized that these snails live deeper than routine surveys explore (57 Federal 

Register 59244). The species is intolerant of pollution. 
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In 1995, the USFWS reported that the Snake River physa snail’s “modern” range 

extended from Grandview (RM 487) to the Hagerman Reach (RM 573). However, 

recently identified specimens collected by the Bureau of Reclamation (Gates and 

Kerans 2010) and Idaho Power Company from 1995 to 2003 (Keebaugh 2009) confirm 

its distribution to as far upstream as Minidoka Dam (RM 675) and as far downstream as 

Ontario, Oregon (RM 368), some 128 miles downstream of its previously recognized 

downstream range (Grandview). Two specimens were recovered from the Bruneau 

River arm (RM 4) of C.J. Strike Reservoir (Keebaugh 2009), representing the only 

tributary of the Snake River in which the species has been recorded. While the species 

is more widespread than previously thought, currently recorded from an estimated 307 

river miles, it has not been found at high densities within much of its current known 

range and is likely absent from portions of the river. The most extensive surveys 

conducted to date are from the 12-mile reach below Minidoka Dam (RM 663–675; 

Gates and Kerans 2010), in which live Snake River physa were recovered from 29 of 

365 samples collected. In plots where they were found, densities were typically 32 per 

square meter, but live animals reached relatively high densities in a few of these 

samples, estimated at 40 to 64 individuals per square meter. Elsewhere in the Snake 

River, surveys have been much less intensive and not specific to Snake River physa. 

Of 758 samples re-examined by Keebaugh (2009) between RMs 200 and 589.2, 

4.5 percent (34) contained Snake River physa. Of those, 67 percent (23) contained a 

single animal (0.25 per square meter) and one sample near Marsing, Idaho (RM 421) 

contained a high of 7 individuals, extrapolating to a density of 28 per square meter. 

Hence, in habitats sampled in the lower Snake River, the species would probably not be 

regarded as ubiquitous or abundant, but rather patchily distributed. River reaches 

upstream of the Hagerman area (est. RM 590) through Milner Reservoir (est. RM 663) 

have not received systematic surveys or re-examination of previously collected 

materials.

3.5.4.5 Population Status

This species is always rare at collection sites. One population, near Grandview, is 

believed to have gone extinct since the early 1980s (57 Federal Register 59244). The 

Snake River physa snail is considered to be critically imperiled (NatureServe 2011).

3.5.4.6 Critical Habitat

No critical habitat has been designated for the Snake River physa snail.

3.5.4.7 Environmental Baseline

Species Presence

The entire known range of this species along the Snake River lies within the Action 

Area, between Segments 8 and 9 (Figure 3-7).

Habitat

Suitable habitat for the Snake River physa snail could occur from Minidoka Dam (RM 

675) to Ontario, Oregon. This portion of the Snake River in Idaho is heavily influenced 

by human use. Groundwater pumping has resulted in declines of spring discharges 

over the past 60 years. In addition, both fertilizers and animal wastes contribute to 
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groundwater nitrates and these contaminants have been documented to reach toxic 

levels (Tesch et al. 2003; Neely 2005 ). Springs provide an important contribution in 

maintaining/improving water quality in the Snake River and adjacent cold water springs 

within the action area and as such, impacts from over-pumping of the aquifer or 

groundwater contamination can be expected to adversely affect habitats occupied by 

listed Snake River snails. Agricultural uses also impact the water quality of surface 

water sources and conveyances (e.g., streams, irrigation return canals) (Clark et al. 

1998 ). In addition, aquaculture facilities in the middle Snake River region contributes 

wastes from fish food, fish metabolism, and processing (Clark et al. 1998) as well 

residual antibiotic and antiseptic compounds to the Snake River (EPA 2002 ). The 

lethal limits of these threats (e.g., aquifer depletion and spring discharge, increasing 

contaminant risks from growing agricultural industries) on listed Snake River snails are 

not known, but it is likely that continuing degradation and over-consumption of water 

resources (due to increasing human use) will degrade snail habitat and place listed 

Snake River snails at greater risk over time. In addition, listed Snake River snails may 

also be threatened by future introduction of invasive species. 

Critical Habitat

No critical habitat has been designated for the Snake River physa snail.

3.6 Plants

Seven federally threatened or endangered plants potentially occur in the vicinity of the 

Action Area. However, only two of these species—blowout penstemon and Ute ladies’-

tresses—have the potential to be impacted by the Project and are discussed further in 

this BA. One species proposed for listing, slickspot peppergrass, and its proposed 

critical habitat also occur within the Action Area. Additionally, western fringed prairie 

orchid occurs downstream of the Project in the Platte River basin. This species is 

discussed along with other Platte River species (see Section 3.2).

3.6.1 Blowout Penstemon (Endangered)

3.6.1.1 Status

Blowout penstemon was declared to be an endangered species in September 1987 (52 

Federal Register 32926).

3.6.1.2 Threats

Suitable habitat for this species has been reduced by fire reduction management and 

range management practices such as dune stabilization that allow other plant species to 

establish and exclude blowout penstemon. Having evolved to use only early seral 

habitats, blowout penstemon declines as later successional species colonize (USFWS 

2012d), possibly due to competition for moisture. Reducing the distribution of this 

species also makes it less likely that new pockets of suitable habitat will be colonized as 

they arise, compounding the problem. Future development, particularly from energy 

development, may pose threats to occupied blowout penstemon habitat in Wyoming 

(USFWS 2012d). Off-road vehicle use may also impact individual plants and their 

habitat.
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3.6.1.3 Species Recovery

Approximately 13 percent of the Nebraska population of blowout penstemon was on 

USFWS refuge lands in 2008 and 23 percent on Forest Service land (USFWS 2012d). 

Under the ESA and the Nebraska Nongame and Endangered Species Conservation 

Act, it is prohibited to remove individuals of blowout penstemon, and possession, 

transportation, processing, and sale of this species are also regulated. Populations of 

blowout penstemon on BLM-administered land in Wyoming are on land managed by the 

Rawlins Field Office and the BLM Rawlins Office Resource Management Plan contains 

11 conservation measures that apply to areas containing blowout penstemon (USFWS 

2012d).

A recovery plan was published by the USFWS in 1992. The stated recovery objective 

for this species is delisting. The actions needed are listed as (USFWS 1992b):

1. Protect and monitor naturally occurring, reintroduced, and introduced 

populations.

2. Inventory suitable habitat for naturally occurring populations and determine 

potential reintroduction sites.

3. Conduct research to determine life history, minimum viable population 

parameters, and management criteria.

4. Establish new populations of blowout penstemon.

5. Establish and implement management plans for each population.

A 5-year review for blowout penstemon was published in 2012 (USFWS 2012d).

3.6.1.4 Life History, Habitat Requirements, and Distribution

Blowout penstemon is found within the Sandhills region of north central Nebraska, and 

in Carbon and Goshen Counties, Wyoming (NatureServe 2011). In Wyoming, there are 

3 distinct populations and 19 subpopulations of blowout penstemon, most of which 

occur on BLM-managed land (USFWS 2012d). This plant has a narrow distribution and 

is found in open (less than 10 percent vegetative cover) early successional habitat, 

especially blowouts in sand dunes, to which this plant is well adapted. Blowouts are 

craters actively being dug out of sand dunes by the swirling action of prevailing winds, 

and present challenges of wind, temperature, evapotranspiration, and soil moisture 

stress. In Wyoming, blowout penstemon is found primarily on the rim and lee slopes of 

blowouts, or the rim and steep faces of sandy slough slopes at the base of mountains or 

ridges (USFWS 2012d). The numerous fibrous roots are horizontal and can be twice as 

long as the height of the plant, which anchor it well in the sand (NatureServe 2011). 

This species can also recover from sand burial by sending off shoots at successively 

higher nodes. The reproductive strategy of blowout penstemon also appears to be 

suited for constantly colonizing newly formed blowouts. Plants typically flower in the 

second or third year and bees are believed to be the primary pollinators (Kottas 2008;

USFWS 2012d). While in bloom, large quantities of seed are produced; however,

seedlings in natural populations are rare (USFWS 2012d).
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3.6.1.5 Population Status

About 81 natural populations of this plant remain; there are 54 occurrences where 

plants have been introduced, and these locations are threatened by succession 

(NatureServe 2011). In Nebraska, the population of this species increased from 

approximately 2,788 in 1990 to 23,876 individuals in 2008 (Stubbendieck 2008 as cited 

in USFWS 2012d). Population estimates in Wyoming declined from approximately 

19,343 plants in 2005 to estimates of 5,000 to 8,000 plants in 2009 (USFWS 2012d). 

Blowout penstemon is considered to be critically imperiled due to few, small, isolated, 

and apparently not vigorous populations (NatureServe 2011).

3.6.1.6 Critical Habitat

No critical habitat has been designated for this species due to the transient nature of 

suitable dune blowout habitat (52 Federal Register 32928).

3.6.1.7 Environmental Baseline

Species Presence

The closest documented sites to the Action Area where blowout penstemon occurs are 

three separate sites in northwestern Carbon County, Wyoming, approximately 40 miles 

north of Segment 2. These sites comprise approximately 7,000 to 7,800 individuals 

total (Heidel 2005).

Habitat

Detailed vegetation mapping indicates that no sand dune habitat occurs within the 

Action Area; however, the USFWS has indicated that all portions of the Action Area in 

Wyoming are within the potential range for this species (USFWS 2012b); therefore, this 

species will be analyzed in this document.

Critical Habitat

No critical habitat has been designated for this species.

3.6.2 Ute Ladies’-Tresses (Threatened)

3.6.2.1 Status

A proposal to list Ute ladies’-tresses as threatened was filed with USFWS in November 

1990 (55 Federal Register 47350), and the species was listed as threatened in January 

1992 (57 Federal Register 2048).

3.6.2.2 Threats

The primary threats to Ute ladies’-tresses are competition from exotic weeds, vegetation 

succession, habitat loss through development and modification, mowing during 

flowering, grazing by livestock, overcollection, and vulnerability to stochastic events due 

to a slow reproductive rate and scattered distribution of populations (57 Federal 

Register 2048). Additional threats include loss of pollinators, natural herbivory, and 

changes in hydrology (Fertig et al. 2005), as well as absence or rarity of mycorrhizal 

symbionts, and conflicting management with other rare species (USFWS 2013). Much 

of this species’ riparian habitat has been modified or lost due to development, and much 
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of the habitat where remaining populations are located is subject to livestock grazing 

and trampling; however, about 35 percent of known populations are either in protected 

areas or are under some form of special management, and plants can be found in areas 

of human disturbance that were previously thought to be uninhabitable by the species 

(Fertig et al. 2005). The attractive inflorescence of the Ute ladies’-tresses has resulted 

in interest from collectors and wildflower enthusiasts, which threatens remaining 

individuals. Herbicides have the potential to be a threat (57 Federal Register 2048); 

however, the 1995 recovery plan does not list herbicides among the threats facing this 

plant (USFWS 1995b). Monitoring for this plant along the South Fork Snake River in 

2003 found little mortality due to herbicides (Murphy 2004). Ute ladies’-tresses is 

unable to compete with aggressive invasive plants such as reed canarygrass (Phalaris 

arundinacea), cattails (Typha spp.), and Canada thistle (Cirsium arvense; USFWS 

1995c; Fertig et al. 2005). In addition, no federal or state laws or regulations specifically 

addressed protection of this orchid prior to its listing under the ESA, besides a small 

amount of protection afforded by the Clean Water Act. 

3.6.2.3 Species Recovery

Of the eight states in which Ute ladies’-tresses is known to occur, only Nebraska and 

Nevada have state endangered species laws that specifically address vascular plants. 

These states prohibit the removal, destruction, export, possession, and sale of this 

species. Approximately 43 percent of known occupied acreage occurs on federal lands, 

and 49 percent occurs on private lands (Fertig et al. 2005). On federally managed and 

state lands, this species is protected by various land management plans.

A draft recovery plan was developed for Ute ladies’-tresses in 1995. Recovery 

objectives laid out in the plan include:

1. Obtaining information on life history, demographics, habitat requirements, and 

watershed processes that will allow specification of management and population 

goals and monitoring progress;

2. Managing watersheds to perpetuate or enhance viable populations of the orchid;

and

3. Protecting and managing Ute ladies’-tresses populations in wet meadow, seep, 

and spring habitats.

Identified actions needed include:

1. Define, manage, and restore watersheds, using watershed-based interagency, 

interdisciplinary teams as evaluation and planning aids;

2. Identify, protect, and manage populations that occur in wet meadow, seep, and 

spring sites;

3. Inventory remaining potential habitat;

4. Conduct genetic, life history, ecology, and habitat management studies;

5. Reintroduce orchids into appropriate sites; and

6. Conduct public education on watershed and riparian area management, use of 

recovery and interdisciplinary teams, and orchid ecology (USFWS 1995b).
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3.6.2.4 Life History, Habitat Requirements, and Distribution

This long-lived perennial forb likely reproduces exclusively by seed. Fruits are 

produced in late August or September, and seeds are shed shortly thereafter. Once the 

seed disperses to a suitable germination site and establishes a symbiotic mycorrhizal 

relationship, it remains dormant underground until roots are of sufficient size to develop 

above-ground leafy shoots. The number of years that this takes is unknown for Ute 

ladies’-tresses (Fertig et al. 2005), but in autumn ladies’-tresses (Spiranthes spiralis), 

this period lasts 11 years (USFWS 1995b). Shoots are produced in October, persist 

through winter, and resume growth in spring, becoming photosynthetic. Blooms show 

from early July to late October, although autumn ladies’-tresses individuals rarely flower 

in consecutive years or under unfavorable conditions, and this may be true for Ute 

ladies’-tresses as well (USFWS 1995b). Observations of individual Ute ladies’-tresses 

plants have shown that they can demonstrate no aboveground growth for at least one 

growing season (USFWS 1995b). The lifespan of individual plants can be over 50 

years (USFWS 1995b).

Habitat is primarily moist meadows associated with perennial streams, floodplains, and 

lake shores between 720 and 7,000 feet. Human-made features such as irrigation 

canals, berms, levees, gravel pits, and reservoirs are also used. This orchid appears to 

require moisture in the rooting zone through the growing season, which is most often 

provided by a high water table (BLM 2011b). Surrounding vegetation is not dense or 

heavily grazed, and periodic or recent disturbance maintains a minimal amount of 

competition. Most populations occur on lands managed for agriculture, recreation urban 

infrastructure, or open space. In Wyoming, Ute ladies’-tresses has been found near 

perennial streams, and in Idaho it has been found along rivers containing impoundment 

dams and reservoirs, and along supplemental irrigation structures (Fertig et al. 2005).

Ute ladies’-tresses occurs in central Washington, southwestern Montana, eastern Idaho, 

southeastern Nevada, southeastern Wyoming, northern and south-central Utah, central 

Colorado, western Nebraska, and British Columbia (Fertig et al. 2005). In Idaho, this 

plant is known from Bonneville, Fremont, Jefferson, and Madison Counties along the 

Snake River and from wetland sites along the Henry’s Fork River. In Wyoming, it has 

been found in Goshen, Converse, Laramie, and Niobrara Counties (Fertig et al. 2005).

3.6.2.5 Population Status

Increased survey effort for the Ute ladies’-tresses since its listing in 1992 has resulted in 

an expansion of this plant’s known range, from Colorado, Utah, and Nevada to include 

Wyoming, Montana, Nebraska, Idaho, and Washington (Fertig et al. 2005). In 2005, 63

occurrences of Ute ladies’-tresses were recognized, comprising up to approximately 

38,000 individuals (Fertig et al. 2005). Idaho and Wyoming contain a total of four extant 

populations each. Idaho contains an estimated 7,807 individuals (the most found in any 

state), and Wyoming has an estimated 1,212 individuals (Fertig et al. 2005). Population 

trends are very difficult to assess for this species due to great increases in survey 

efforts since listing in 1992 and surveys focusing on flowering plants, which 

underestimates true abundance by an unpredictable amount (Fertig et al. 2005). The 

global status of Ute ladies’-tresses is considered to be imperiled (NatureServe 2011). 
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3.6.2.6 Critical Habitat

Critical habitat for Ute ladies’-tresses has not been designated because publication of 

this information could lead to increased collection of specimens, further threatening the 

persistence of this species, especially due to its very low reproductive rate (57 Federal 

Register 2052).

3.6.2.7 Environmental Baseline

Species Presence

This species occurs in moist stream banks, wet meadows, and abandoned stream 

channels in Idaho and Wyoming; however, Ute ladies’-tresses is not known to occur in 

the Action Area. No portions of the Action Area in Idaho are in counties where Ute 

ladies’-tresses is known or expected to occur. In Wyoming, this species has been 

reported from Goshen, Laramie, Converse, and Niobrara Counties. The closest known 

occurrences of Ute ladies’-tresses to the Action Area are in northern Bonneville County, 

Idaho, approximately 80 miles north of Segment 4; and in northwestern Converse 

County, Wyoming, approximately 40 miles north of Segment 1W (Fertig et al. 2005; 

BLM 2007). Species-specific surveys for Ute ladies’-tresses were conducted in areas of 

potential suitable habitat within the Action Area along Segment 1W and Segment 5 in 

2009, 2010, 2011, and 2012; no plants were found during these surveys (see Section 

2.3 – Field Surveys). Tables 3-4 and 3-5 list areas where surveys were conducted and 

the results of these surveys.

Habitat

Ute ladies’-tresses could be found in potential habitat (riparian and wetland areas) 

containing suitable characteristics along Segments 1W, 2, 3, 4, and 5. Known 

observations of Ute ladies’-tresses; however, only occur north of Segment 1W in 

Wyoming and north of Segment 4 in Idaho. Additionally, review of existing habitats and 

elevation in the Action Area and information provided by the BLM, USFWS, Wyoming 

Natural Diversity Database, and IDFG indicate that the likelihood of finding potential Ute 

ladies’-tresses or potential habitat is low along Segments 2, 3, and 4 and that portions 

of Segment 1W in Wyoming and Segment 5 in Idaho have the highest likelihood of 

containing suitable potential habitat for Ute ladies’-tresses. Surveys were conducted 

between 2009 and 2012 in 27 areas, 22 along Segments 1W and 5 along Segment 5, 

that were identified as potentially containing suitable habitat for Ute ladies’-tresses. 

Little or no suitable habitat; however, was documented within most of the areas

surveyed (Tables 3-4 and 3-5). In areas containing suitable habitat features for some 

criteria (e.g., those with broad floodplains, perennial hydrology, or suitable soils), most 

were too heavily vegetated and/or disturbed by grazing to support the species. Other 

sites either lacked a floodplain or did not exhibit suitable hydrological and soil 

characteristics. During the surveys, only 4 of the 25 areas surveyed (all along Segment 

1W) were identified as containing suitable potential habitat for Ute ladies’-tresses 

(Table 3-5). 
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Table 3-4. Ute Ladies’-tresses Survey Results: Segment 1W 

Area ID

Drainage 

Name Results

Years 

Surveyed

Potential 

habitat? 1/

Resurvey 

(Years 

Remaining) 2/

Area 1 Deer Creek

Large perennial, low sinuosity stream. Large boulders, sandy rocky 

cobble, and gravel stream bed with no developed floodplain. 

Forested riparian zone with dense vegetation along banks.

2009, 2010, 

2011, 2012 Yes 0

Area 2 Hess Draw Not a stream channel. No hydrology. 2009 No No

Area 3 Negro Creek Intermittent stream with areas of ponded water. Densely vegetated, 

heavily grazed and hummocked. Heavy soils. 2009 No No

Area 4 Bates Creek Stream intermittent within the study area. Standing water. Dense, 

rhizomatous vegetation. Heavily grazed and hummocked.

2009 No No

Area 5 East Spring 

Creek

Perennial stream, numerous springs and seeps, some alluvial 

deposition and sand bars, a large un-shaded floodplain with a high 

groundwater table. Dense, rhizomatous vegetation and heavily 

grazed.

2009 No No

Area 6 Indian Creek Steeply entrenched perennial stream. Narrow floodplain. 

Predominantly shaded with mature riparian overstory.

2009 No No

Area 7 North Fork 

Deer Creek No Access Not surveyed Access required to assess habitat Yes (3?)3/

Area 8 Deer Creek

Intermittent drainage with wide floodplain, heavily shaded, with 

mature riparian overstory. With scattered pools of standing, 

stagnant water.

2010 No No

Area 9 Little Deer 

Creek

Forested riparian/wetland. Meandering perennial stream with no 

developed floodplain. Heavily shaded with de87nse overgrown 

vegetation.

2010 No No

Area 10 Willow 

Creek

Shrub and herbaceous riparian/wetland zone. Heavily shaded 

meandering stream with moderate floodplain in places. Poorly 

drained soil.

2010 No No

Area 11 West Fork 

Deer Creek Need to add when receive final 2011 or 2012 survey report 2011, 2012 No No

Area 12 Spring 

Creek Sedge dominated community with moderate grazing. 2011, 2012 Yes Yes (1)

Area 13 King Creek Need to add when receive final 2011 or 2012 survey report 2011, 2012 No No

Area 14 King Creek Need to add when receive final 2011 or 2012 survey report 2011, 2012 No No

Area 15 King Creek Sedge dominated community with moderate grazing. 2011, 2012 Yes Yes (1)

Area 16 Andys Creek Sedge dominated community with moderate grazing. 2011, 2012 No (2010); Yes 

(2011) Yes (1)

Area 17 Soldier 

Creek No Access Not surveyed Access required to assess habitat Yes (3?)3/

Area 18 Deer Creek Despite permission, attempts to access this area failed. 2011 No No
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Table 3-4. Ute Ladies’-tresses Survey Results: Segment 1W (continued)

Area ID

Drainage 

Name Results

Years 

Surveyed

Potential 

habitat? 1/

Resurvey 

(Years 

Remaining) 2/

Area 19 Deer Creek

Four foot wide perennial meandering stream with stable bank, not 

incised. Situated within wide floodplain. Dense rhizomatous 

vegetation with moderate grazing. 

2010 Yes Yes (2)

Area 20 Texas Creek

Narrow, low flow ephemeral meandering stream with narrow 

unshaded floodplain. Dense rhizomatous vegetation with light 

grazing

2010, 2011 Yes (2010); No 

(2011) No

Area 21 Curry Creek

Narrow, meandering perennial stream within broad 

grassland/shrub valley. Slight imbedding, cutbanks. A large 

unshaded floodplain with a high groundwater table. Dense, 

rhizomatous vegetation; heavily grazed. 

2010, 2011 Yes (2010); No 

(2011) No

Area 22 Sandell 

Creek

Meandering ephemeral stream with areas of silty clay surrounding 

well drained areas of granite cobble/gravel. Wide flood plain, no 

shade, no water. Site feeds large stock pond. Area heavily grazed. 

2010 No No

1/ Potential habitat characteristics include:

 Perennial hydrology or a water table within 18 inches of the surface;

 Existence of a stabilized floodplain or terraces; 

 Well drained soils;

 Locations in full sun and low vegetation density; and

 Low occurrence of disturbance.

2/ Number of survey years remaining to meet the required protocol of 3 years of surveys, if applicable. Areas where no potential habitat exists do not need to be resurveyed.

3/ Area has not been surveyed on the ground. If surveys demonstrate that no potential habitat exists, no additional surveys will be needed.

Table 3-5. Ute Ladies’-tresses Survey Results: Segment 5 

Area 

ID Drainage Name Results

Years 

Surveyed

Potential 

habitat? Resurvey

Area 1 Bannock Creek Heavily grazed upland community situated on bench above floodplain. 

Spring seep from nearby irrigation ditch. 2010 No No

Area 2 Bannock Creek Perennial stream and spring with poorly drained clay soils. Stagnant 

water source present and evidence of heavy grazing 2010 No No

Area 3 Moonshine Creek

15 foot wide entrenched perennial stream. Steep banks, no developed 

floodplain. Evidence of heavy grazing disturbance. Dense rhizomatous 

vegetation with poorly drained loam soils. 

2010 No No

Area 4 Moonshine Creek Perennial stream with evidence of heavy grazing disturbance. No 

developed floodplain. Dense rhizomatous vegetation. 2010 No No

Area 5 Moonshine Creek Heavily grazed, dense rhizomatous vegetation. No developed floodplain. 2010 No No

1/ Potential habitat characteristics include:

 Perennial hydrology or a water table within 18 inches of the surface;

 Existence of a stabilized floodplain or terraces; 

 Well drained soils;

 Locations in full sun and low vegetation density; and

 Low occurrence of disturbance.
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Critical Habitat

No critical habitat has been designated for this species.

3.6.3 Slickspot Peppergrass (Proposed for Listing as Endangered)

3.6.3.1 Status

Slickspot peppergrass was proposed for listing as endangered in 2002 (67 Federal 

Register 46441), was withdrawn from consideration in 2004 (69 Federal Register 3094), 

was reinstated as a proposed endangered species in October 2006 (71 Federal 

Register 62078), was again withdrawn from consideration for listing in 2007 (72 Federal 

Register 1622), and was again proposed for listing in 2008 based on a U.S. District 

Court ruling (73 Federal Register 54345). In October 2009, slickspot peppergrass was 

listed as threatened (74 Federal Register 52014). However, on August 8, 2012, the 

U.S. District Court in Boise, Idaho, vacated this listing and remanded it for further 

consideration. The Court vacated the listing on the grounds that the USFWS failed to 

specify the time frame when the plant will become endangered. As a result, at this time 

the USFWS currently considers the slickspot peppergrass to be a proposed species 

under the Act, as they await further legal guidance regarding the court’s decision.

During this interim period (i.e., until a final decision regarding the listing status of this 

species is determined), the BLM has decided to conference on the slickspot 

peppergrass, under section 7 of the ESA, to ensure conservation of the species and to 

adhere to the Conservation Agreement for slickspot peppergrass between the BLM and 

the USFWS. Therefore, this species and its proposed critical habitat are addressed 

within this BA.

3.6.3.2 Threats

The primary threat to slickspot peppergrass is destruction or modification of its habitat 

due to changes in the fire regime and invasion by nonnative plants, particularly 

cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae). 

Invasion of native sagebrush-steppe by annual grasses such as cheatgrass increases 

the frequency and severity of fires, which slickspot peppergrass and the native 

sagebrush-steppe ecosystem in which it occurs are not adapted to (USFWS 2011b). 

These fires also burn more uniformly, leaving no pockets of unburned native vegetation 

that could reseed burned areas. This change in the fire regime reduces the abundance 

of slickspot peppergrass and its native plant associates, and is conducive to the further 

spread of these invasive grasses, thus creating a self-perpetuating cycle (74 Federal 

Register 52014). In addition, cheatgrass competes directly with slickspot peppergrass. 

Another serious threat to slickspot peppergrass is development, both agricultural and 

residential, which results in direct destruction of plants, seedbanks, and slickspots, and 

also fragments and isolates populations. Fragmentation of populations and loss of 

pollinators is considered a moderate threat. Trampling by livestock, military training, 

and recreation are considered minor threats (74 Federal Register 52014).

3.6.3.3 Species Recovery

A Candidate Conservation Agreement between the State of Idaho, BLM, Idaho Army 

National Guard, and nongovernmental cooperators (private land owners who also hold 

BLM livestock grazing permits) has been in place for conservation of this species since 
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December 2003. There is also a 2006 conservation agreement between the BLM and 

USFWS for slickspot peppergrass that outlines conservation measures protecting this 

species. This 2006 agreement was updated in 2009, and is currently being evaluated 

for a 2013 update.

3.6.3.4 Life History, Habitat Requirements, and Distribution

Slickspot peppergrass is a small flowering plant in the mustard family (Brassicaceae) 

that grows in unique microsite habitats known as slickspots found within the semiarid 

sagebrush-steppe ecosystem in Ada, Canyon, Elmore, Gem, Owyhee, and Payette 

Counties of southwestern Idaho. It does not occur in Wyoming. The species is 

endemic to this region, known only from the Snake River Plain and its adjacent northern 

foothills (an area approximately 90 by 25 miles), with a smaller disjunct population on 

the Owyhee Plateau. Approximately 95 percent of the occupied slickspot peppergrass

habitat occurs on federal lands (BLM, U.S. Air Force, Bureau of Reclamation). The 

remaining occupied habitat is in State of Idaho ownership or privately owned (USFWS 

2011b).

Slickspot peppergrass occurs primarily in slickspot microsites, visually distinct openings 

characterized by areas of high sodium content and distinct clay layers, scattered within 

the greater semiarid sagebrush-steppe ecosystem of southwestern Idaho. Slickspots 

are distinguished from the surrounding sagebrush matrix by having the following 

characteristics: water pools when rain falls (Fisher et al. 1996), sparse vegetation, 

distinct soil layers with a columnar or prismatic structure, high alkalinity and clay content 

and natric properties (Fisher et al. 1996; Meyer and Allen 2005; Palazzo et al. 2008), 

and reduced levels of organic matter and nutrients due to lower biomass production 

(Meyer and Quinney 1993; Fisher et al. 1996). Fisher et al. (1996) describe slickspots 

as having a “smooth, panlike surface” that is structureless and slowly permeable when 

wet and moderately hard and cracked when dry. Although the low permeability of 

slickspots helps hold moisture (Moseley 1994), once the thin crust dries out the survival 

of slickspot peppergrass seedlings depends on the ability to extend the taproot into the 

argillic horizon and extract moisture from the deeper saline, sodic, natric zone (Fisher et 

al. 1996). Slickspots are scattered within a matrix of sagebrush steppe habitat. Menke 

and Kaye (2006a) describe high quality matrix habitat conditions for slickspot 

peppergrass as sagebrush-steppe habitat in late seral condition, and Fisher et al. 

(1996) note that “habitat with vigorous slickspot peppergrass populations has not been 

recently burned, is not heavily grazed, and has an understory of native bunchgrasses 

and a well-developed microbiotic soil crust.” The climatic conditions that allowed for the 

formation of slickspots are thought not to exist presently, and therefore the loss or 

destruction of a slickspot is considered permanent. Likely due to its dependence on 

specific soil conditions, slickspot peppergrass is only rarely found outside of slickspots 

(Menke and Kaye 2006b).

Slickspot peppergrass has an annual or biennial life history strategy. Aboveground 

populations may fluctuate greatly from year to year depending on precipitation and other 

factors. The aboveground plants represent only a small portion of the population, most 

of which is present in the soil seed bank because only a fraction of seeds germinate in a 

given year (Mancuso and Moseley 1998; Meyer et at. 2005). Although a slickspot may 
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not contain aboveground plants in a given year, they may contain viable slickspot 

peppergrass seeds (USFWS 2011b). 

3.6.3.5 Population Status

Increased survey efforts for slickspot peppergrass have resulted in an increase in the 

amount of known occupied habitat, although the known range of this species has not 

substantially expanded. The historic and extant distribution of slickspot peppergrass is 

tracked by the Idaho Natural Heritage Program through the use of element occurrences 

(EOs) (USFWS 2011b). All occupied slickspots within a 0.6-mile distance of another 

occupied slickspot are combined into a single EO (USFWS 2011b). Each EO is then 

given a letter ranking (A, B, C, D, E, F, H, or X) based on habitat quality and the 

abundance of slickspot peppergrass within the EO. Higher rankings (“A” is the highest 

ranking) indicate sites with greater habitat quality and larger population sizes and B, C, 

and D rankings indicating a decreasing continuum of detectable plants, native plant 

community, habitat condition, and overall landscape context within 0.6 mile of occupied 

slickspots, with a B ranking signifying a greater number of plants and better habitat 

conditions and a D ranking signifying few plants and poor conditions (USFWS 2011b). 

As of 2009, approximately 80 EOs of this species were extant and most of these extant 

EOs were small and threatened by ongoing habitat loss (USFWS 2011b). 

Slickspot peppergrass abundance has declined in the past, and its current range-wide 

short-term trend is rapidly to very rapidly declining (NatureServe 2011). The exact trend 

is difficult to ascertain, however, partly due to the wide variability in the number of 

aboveground-flowering individuals in a given year; only a small fraction of slickspot 

peppergrass seeds germinate annually (USFWS 2011b).

3.6.3.6 Critical Habitat

Critical habitat was proposed for slickspot peppergrass on May 10, 2011 (76 Federal 

Register 27184), which includes a total of 57,756 acres. Due to the current uncertainty 

on the status of the species under the Act subsequent to the August 2012 court 

decision, the future date of final critical habitat designation for slickspot peppergrass is 

unknown. Four units of critical habitat are proposed, one each in Payette, Ada, Elmore, 

and Owyhee Counties, Idaho. The four PCEs are:

1. Ecologically functional microsites or “slickspots,” characterized by:

a. High sodium and clay content and a three-layer soil horizonation 

sequence.

b. Sparse vegetation with low to moderate introduced, invasive, non-native 

plant species cover.

2. Relatively intact, native Wyoming big sagebrush vegetation assemblages, 

represented by native bunchgrasses, shrubs, and forbs, within 820 feet of 

slickspot peppergrass element occurrences to protect slickspots and plants from 

disturbance from wildlife, slow the invasion of slickspots by non-native species 

and native harvester ants, and provide the habitats needed by slickspot 

peppergrass’s pollinators.
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3. A diversity of native plants whose blooming times overlap to provide pollinator 

species with sufficient flowers for foraging throughout the seasons and to provide 

nesting and egg-laying sites; appropriate nesting materials; and sheltered, 

undisturbed places for hibernation and overwintering. In order for genetic 

exchange of slickspot peppergrass to occur, pollinators must be able to move 

freely between slickspots. Alternative pollen and nectar sources are needed to 

support pollinators during times when slickspot peppergrass is not flowering, 

when distances between slickspots are large, and in years when slickspot 

peppergrass is not a prolific flowerer.

4. Sufficient pollinators for successful fruit and seed production, particularly 

pollinator species of the sphecid and vespid wasp families, species of the 

bombyliid and tachnid fly families, honeybees, and halictid bee species, most of 

which are solitary insects that nest outside of slickspots in the surrounding 

sagebrush-steppe vegetation, both in the ground and within the vegetation.

3.6.3.7 Environmental Baseline

As described above (Section 3.6.3.2 – Threats), modification of habitat, changes to fire 

regime, invasion by non-native plants, and development have reduced the amount and 

suitability of potential habitat for slickspot peppergrass and has resulted in direct loss of 

individuals across its range, including within the Action Area. The status of slickspot 

peppergrass within the Action Area is further discussed below.

Species Presence

Eleven known occurrences of slickspot peppergrass are found within the Action Area,

five of which would be crossed by Segment 8 (Figure 3-8). The majority of the EOs 

within the Action Area and bisected by the Project are ranked as “C” and two of the 

occurrences are ranked as “F” (failed to find). Table 3-6 below summarizes the acres of 

known occurrences of slickspot peppergrass, by EO number and rank that occur within 

the Action Area and within the Project footprint. 
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Figure 3-8a. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and Potential Habitat in relation to the Project

(Map 1)
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Figure 3-8b. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and Potential Habitat in relation to the Project

(Map 2)
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Figure 3-8c. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and Potential Habitat in relation to the Project

(Map 3)
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Figure 3-8d. Slickspot Peppergrass Proposed Critical Habitat, Occupied Habitat, and Potential Habitat in relation to the Project

(Map 4)
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Table 3-6. Acres of Known Occurrences of Slickspot Peppergrass within the Action Area 

and Crossed by the Project Footprint, by Element Occurrence1/

EO 

Number EO Rank2/ Acres Within Action Area Acres Within Project Footprint3/

15 D 47.0 --

18 C 21.8 --

24 C 90.4 1.7

25 C 14.9 --

30 B 156.8 <0.01

31 C 71.5 1.3

42 F 2.1 0.03

51 BD 3.6 --

54 F 0.5 --

72 C 19.4 --

104 C 80.6 0.2

Total 508.6 3.2

1/ All known occurrences within the Action Area and crossed by the Project footprint occur along Segment 8.

2/ Only acres of extant EOs included in table; extirpated occurrences not included.

EO Rank Definitions (from Colket et al. 2006): 

A-Rank: SIZE: >1000 detectable genets. CONDITION: Native plant community is intact with trace introduced plant species cover. 

Slickspots have zero or trace introduced weed cover and/or livestock disturbance. Zero or few minor anthropogenic disturbances 

are present. EO is unburned. LANDSCAPE CONTEXT: Surrounding landscape less than 1 km away has not been fragmented by 

agricultural lands, residential or commercial development, introduced annual grasslands, or drill seeding projects.

B-Rank: SIZE: 400–999 detectable genets. CONDITION: Native plant community is intact with low introduced plant species cover. 

Slickspots have low introduced weed cover and/or livestock disturbance. Zero or few minor anthropogenic disturbances present. EO 

is predominantly unburned. LANDSCAPE CONTEXT: Surrounding landscape less than 0.6 mi away is minimally to partially 

fragmented by agricultural lands, residential or commercial development, introduced annual grasslands, or drill seeding projects. 

C-Rank: SIZE: 50–399 detectable genets. CONDITION: Native plant community is partially intact with low-to-moderate introduced 

plant species cover. Slickspots have low-to-moderate introduced weed cover and/or livestock disturbance. Few or several minimally 

to moderately severe anthropogenic disturbances are evident. EO has partially burned. Portions of EO may have been drill seeded, 

but slickspots are largely intact. LANDSCAPE CONTEXT: Surrounding landscape less than 0.6 mi away is partially to predominantly 

fragmented by agricultural lands, residential or commercial development, introduced annual grasslands, or drill seeding projects. 

D-Rank: SIZE: 1–49 detectable genets. CONDITION: Few components of the native plant community remain and introduced plant 

species cover is high. Slickspots have high introduced weed cover and/or livestock disturbance. Few or several moderately severe 

anthropogenic disturbances are evident. EO has been predominantly to completely burned. Portions of EO may have been drill 

seeded, and slickspot soils have been altered by drill seeding. LANDSCAPE CONTEXT: Surrounding landscape less than 0.6 mi 

away is moderately to completely fragmented by agricultural lands, residential or commercial development, introduced annual 

grasslands, or drill seeding projects. 

F-Rank (Failed to find): EO has been surveyed by experienced individuals who failed to find any slickspot peppergrass individuals, 

despite searching under conditions appropriate for the element at a location where it was previously recorded. 

3/ Acres do not include the Project right-of-way as vegetation clearing within the right-of-way would only occur in forested vegetation 

communities.

Habitat

Occupied slickspot peppergrass habitat1 and slickspot peppergrass habitat would be 

crossed by Segment 8 of the Project. Potential slickspot peppergrass habitat would be 

crossed by Segments 8 and 9 (Figure 3-8). Approximately 11,108.8 acres of slickspot 

peppergrass occupied habitat occurs within the Action Area and 248.1 acres occurs 

within the Project footprint. Table 3-7 displays the acres of occupied slickspot habitat, 

by EO, that occur within the Action Area and are crossed by Segment 8.

 

1 Three habitat categories are used by the BLM for slickspot peppergrass: occupied habitat, slickspot peppergrass 

habitat, and potential habitat. See Attachment A of this document for definitions of these habitat categories.
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Table 3-7. Acres of Slickspot Peppergrass Occupied Habitat within the Action Area and 

Bisected by the Project Footprint, by Element Occurrence1/ 

EO 

Number EO Rank2/ Acres Within Action Area Acres Within Project Footprint3/

15 D 623.7 13.8

18 C 661.7 17.6

24 C 2,643.9 63.1

25 C 913.5 44.3

30 B 1,266.6 7.2

31 C 975.0 16.8

42 F 592.5 12.8

51 BD 767.7 2.6

54 F 326.3 4.6

62 C 176.2 --

72 C 914.4 23.9

104 C 1,123.8 41.4

105 D 123.5 --

Total 11,108.8 248.1

1/ All acres of occupied habitat within the Action Area and within the Project footprint occur along Segment 8.

2/ EO Rank Definitions: See Table 3-6 above. 

3/ Acres do not include the Project right-of-way as vegetation clearing within the right-of-way would only occur in forested vegetation 

communities.

Approximately 20,878.5 acres of slickspot peppergrass habitat and 49,414.8 acres of 

potential habitat occur within the Action Area. Approximately 515.5 acres of slickspot 

peppergrass habitat and 815.6 acres of potential habitat for slickspot peppergrass occur 

within the Project footprint (Table 3-8). 

Table 3-8. Acres of Potential Habitat and Slickspot Peppergrass Habitat and within the 

Action Area and Project Footprint

Segment

Habitat Category 1/

Potential Habitat Slickspot Peppergrass Habitat

Action Area

(Acres)

Project 

Footprint 

(Acres)

Action Area

(Acres)

Project 

Footprint 

(Acres)

Segment 8 20,034.0 382.6 20,878.5 515.4

Segment 9 29,380.8 433.0 – –

Total2/ 49,414.8 815.6 20,878.5 515.4

1/ Three habitat categories are used by the BLM for slickspot peppergrass: occupied habitat, slickspot peppergrass habitat, and 

potential habitat. See Attachment A of this document for definitions of these habitat categories.

2/ Acres do not include the Project right-of-way as vegetation clearing within the right-of-way would only occur in forested vegetation 

communities.

Habitat Integrity and Population Monitoring Data

Monitoring data for slickspot peppergrass have been collected since the late 1990s 

(Colket 2006). Habitat Integrity and Population (HIP) monitoring protocol was developed 

in 2004 to monitor and assess slickspot peppergrass abundance, habitat integrity, and 

disturbance, for the purpose of evaluating and improving management actions 

implemented by the Candidate Conservation Agreement (Colket 2006). This monitoring 

protocol replaced the previously used habitat integrity index monitoring protocol. 
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Between 2004 and 2005, 79 permanent HIP transects were established within slickspot 

peppergrass EOs and various attributes, such as abundance, habitat condition, and 

disturbance, have been measured annually within each slickspot along transect (Colket 

2006; Kinter et al. 2012). 

Table 3-9 displays the HIP transects and Management Areas associated with known 

occurrences or occupied habitat of slickspot peppergrass that occur within the Action 

Area and could potentially impacted by Project activities.

Table 3-9. HIP Transect and Associated EOs and Management Area within the Action Area

Management Area HIP Transect Number EO Number/ (Rank)1/

6

018A; 018B; 019A 18 (C)

024 24 (C) 

025 25 (C)

042 42 (F)

8A

015 15 (D) 

030B 30 (B)

031 31 (C)

8B

054 54 (F)

072B; 072C 72 (C)

072A 104 (C)

9 051A; 051B 51 (BD)

062 62 (C)

N/A2/ N/A 105 (D)

1/ EO Rank Definitions: See Table 3-6 above. 

2/ No Management Area or HIP monitoring transect is currently associated with this EO. Monitoring data 

for EO 42, a nearby EO, are used to characterize baseline conditions for this EO in this analysis.

HIP monitoring data characterizing the baseline conditions of slickspot occurrences and 

occupied habitat from 2004 through 2011 are described below in Tables 3-10 through 

3-13. Additional data on slickspot habitat attributes (e.g., ground disturbance, condition 

of native vegetation) have been collected for HIP transects. Summaries of the baseline 

conditions of these parameters, as well as the potential effects of the Project on 

baseline conditions within slickspot peppergrass occupied habitat in the Action Area,

are described in Attachment A (Effects Determination Checklist for Slickspot 

Peppergrass).

Table 3-10. Unseeded Non-native Plant Cover (Percent) (Colket 2009; Kinter et al. 2010, 

2011, 2012)

HIP Transect 

Number

Year

2004 2005 2006 2007 2008 2009 2010 2011

015 4.6 8.2 7.6 14.1 1.3 6.5 4.8 8.7

018A 34.5 30.0 14.5 11.2 2.7 3.2 17.5 37.3

018B 25.5 6.7 12.6 15.2 3.2 1.3 3.0 8.2

019A 20.1 26.3 9.6 11.1 4.4 13.3 45.5 38.3

024 32.8 47.0 66.3 55.0 21.9 27.7 46.3 66.3

025 32.8 35.5 52.5 57.5 6.6 3.2 30.8 37.5

030B 1.2 14.1 7.7 29.0 6.6 4.1 10.3 12.5

031 1.0 1.5 3.7 7.1 2.0 2.4 5.2 7.2

042 No data 22.5 57.3 57.3 32 17.5 66.8 76.3

051A 0.7 3.9 2.0 1.5 1.8 1.3 1.8 4.4
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Table 3-10. Unseeded Non-native Plant Cover (Percent) (Colket 2009; Kinter et al. 2010, 

2011, 2012) (continued)

HIP Transect 

Number

Year

2004 2005 2006 2007 2008 2009 2010 2011

051B 1.0 1.5 1.7 1.7 1.3 0.5 6.1 11.4

054 No data 3.7 10.1 5.3 2.5 4.4 10.1 6.3

062 No data 4.4 6.7 2.0 1.8 4.9 8.0 3.5

072A 21.5 25.5 35.0 10.3 8.4 11.2 15.2 21.4

072B 17.5 15.5 27.8 8.2 3.7 12.6 7.7 9.6

072C 13.5 9.0 14.1 8.8 4.1 11.2 9.2 14.6

Table 3-11. Seeded Non-native Plant Cover (Percent) (Colket 2009; Kinter et al. 2010, 2011, 

2012)

HIP Transect 

Number

Year

2004 2005 2006 2007 2008 2009 2010 2011

015 0 0 0 0 0 0 0 0

018A 0 0 0 0 0 0 0 0

018B 0.4 0.1 0.3 0 0 0.1 0 0.1

019A 3.1 3.7 0.3 0.1 0 0.1 0.2 0.3

024 0.1 1.6 1.5 0 1.0 1.5 1.3 1.3

025 0 0 0 0 0 0 0 0

030B 0 0 0 0 0 0 0 0

031 0 0 0 0 0 0 0 0

042 0 0 0 0 0 0 0 0

051A 0 0 0 0 0 0 0.1 0

051B 0 0 0 0 0 0 0 0

054 0 0 0 0 0 0 0 0

062 0 0 0 0 0 0 0 0

072A 0 0.1 0 0 0 0 0 0

072B 0 0 0 0 0 0 0 0

072C 1.9 0.7 0.2 0.1 0.4 0.3 0.3 1.0

Table 3-12. Biological Soil Crust Cover in HIP Transect Slickspots (Percent) (Colket 2009; 

Kinter et al. 2010, 2011, 2012)

HIP Transect 

Number

Year

2004 2005 2006 2007 2008 2009 2010 2011

015 5.3 5.1 43.3 33.5 2.4 15.1 38.8 50.5

018A 12.4 12.3 47.6 30.6 33.9 27.5 21.6 40.6

018B 33.1 25.6 55.0 35.3 53.8 36.0 45.0 73.3

019A 20.2 21.3 57.8 43.3 54.5 57.3 37.9 47.3

024 14.5 29.3 47.3 34.8 45.8 21.4 23.2 29.5

025 39.3 20.9 70.1 54.8 60.0 49.6 42.3 52.1

030B 19.1 44.0 44.3 43.3 46.3 38.1 41.3 59.5

031 15.1 61.3 45.0 37.0 44.6 47.3 59.5 57.3

042 No data 37.0 52.0 55.0 66.8 61.3 43.0 62.5

051A 52.8 40.9 55.0 57.0 61.0 36.1 44.3 53.8

051B 53.3 61.3 64.3 57.3 48.0 36.8 28.5 69.0

054 No data 12.6 15.1 3.7 4.8 7.1 19.5 31.9

062 No data 17.3 52.0 35.0 26.5 7.2 17.5 22.6

072A 32.0 29.8 53.5 37.0 37.8 38.4 43.5 48.0

072B 21.0 24.5 32.1 31.5 21.2 21.1 31.0 44.8

072C 25.5 15.9 57.5 25.0 22.8 19.4 36.9 35.6
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Table 3-13. Population Data – Total Slickspot Peppergrass Plants (Colket 2009; Kinter et al. 

2010, 2011, 2012)

HIP Transect 

Number

Year

2004 2005 2006 2007 2008 2009 2010 2011

015 49 37 20 108 417 932 158 3

018A 581-780 653 33 336 391 86 4660 192

018B 332 498 298 923 1585 454 3622 1744

019A 0 0 0 0 1 0 1 0

024 386-634 171 42 0 170 83 596 104

025 1002-1449 455 42 112 375 248 1453 120

030B 1 6 2 3 5 0 0 0

031 5 59 42 458 388 242 51 0

042 No data 0 0 0 0 0 0 0

051A 175-224 860 65 2 315 91 45 26

051B 18 60 25 4 20 7 3 3

054 No data 0 0 0 0 0 0 0

062 No data 297 9 0 19 8 16 11

072A 728-927 480 13 5 170 10 61 0

072B 98 295 172 388 437 143 35 0

072C 218 195 21 45 115 38 14 0

Critical Habitat

Two units (Units 2 and 3) of proposed critical habitat are located near Segment 8. 

Approximately 4.3 miles of Segment 8 would cross through proposed slickspot 

peppergrass critical habitat (Figure 3-8). Approximately 4,378.8 acres of proposed 

critical habitat occur within the Action Area, the majority of which (approximately 51 

percent) is within Subunit 2b (Table 3-14). Approximately 188.6 acres2 of proposed 

critical habitat, 180.5 acres in Unit 2 and 8.1 acres in Unit 3, occur within the Project 

footprint. Table 3-15 summarizes, by subunit and Project component, the acres of 

proposed critical habitat that occur within the Project footprint.

Table 3-14. Acres of Proposed Critical Habitat, by Subunit, within the Action Area 

Critical Habitat 

Subunit

Acres of Proposed Critical 

Habitat1/

2b 2,243.4

2d 934.9

3a 883.5

3b 317.0

Total 4,378.8

1/ All acres of proposed critical habitat within the Action Area occur along Segment 8.

 

2 Acres are for entire Project footprint including entire ROW. Only a portion of the ROW would be disturbed for Project 

construction and operation and maintenance.
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Table 3-15. Acres of Proposed Critical Habitat within the Project Footprint, by Subunit and

Project Component

Project Segment and 

Component1/

Critical Habitat Subunit (Acres) Total by 

Project 

2b 2d 3a 3b Component

Segment 8

Crossing -- 0.03 -- -- 0.03

Deadend Pulling – 500kV 

(1-SC)

3.8 6.9 -- -- 10.7

Existing Road - Improved 11.4 4.3 6.0 2.1 23.8

Fly Yard 12.4 11.8 -- -- 24.2

New Road 2.4 3.7 -- -- 6.1

Pad – 500kV 16.6 8.6 -- -- 25.2

Pulling-Tensioning –

500kV (1-SC)

3.7 -- -- -- 3.7

Total by Subunit 50.3 35.3 6.0 2.1 93.7

1/ Acres do not include the Project right-of-way as vegetation clearing within the right-of-way would only occur in forested 

vegetation communities.

3.7 Cumulative Impacts

This section establishes the baseline conditions related to cumulative effects and

defines the list of reasonably foreseeable future actions that could occur within the 

Action Area. Cumulative effects as they related to specific species are addressed in 

Section 4.

Projects identified in the cumulative effects analysis area include transmission lines, 

pipelines, road projects, power generation facilities, and resource extraction projects. 

High-voltage transmission lines (typically 115-, 230-, 345-, or 500-kV) carry electricity long 

distances and begin and end at substations that serve as either generation or load 

centers. Large-diameter pipelines (at least 12 inches for liquids and at least 24 inches for 

natural gas) transport liquid petroleum products or natural gas long distances. Power 

generation facilities include coal-fired, oil-fired, diesel-fired, and natural gas-fired power 

plants; geothermal facilities; wind energy facilities; hydroelectric projects; biomass and 

cogeneration facilities; and solar facilities. Resource extraction activities found in the area

include coal, trona, crude oil, petroleum products, natural gas, and phosphate. 

Existing projects occurring within the species ranges are included in Table 3-16. 

Mineral leases and oil and gas fields were analyzed by overall acreages for the 

resource and assessed for the acres occurring within range of the species of interest. 
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Table 3-16. Existing Projects considered within the Cumulative Effects Analysis

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Transmission 

Lines

Amps to Tap PacifiCorp Federal 34 miles Canada lynx linkage 

habitat7/

5 miles

Anaconda (Mill Creek) to 

Peterson Flats

NorthWestern Corp Federal 83 miles grizzly bear5/ 10 miles

Canada lynx linkage 

habitat7/

8 miles

Antelope to Yellowcake PacifiCorp Federal 45 miles Preble's meadow jumping 

mouse4/

45 miles

Archer to Stegall Western Area Power 

Administration

Private 61 miles Preble's meadow jumping 

mouse4/

50 miles

Atlantic City to Wyopo PacifiCorp Federal 29 miles Canada lynx linkage 

habitat7/

7 miles

grizzly bear5/ 29 miles

Ault to Craig (Co) Western Area Power 

Administration

Federal 181 miles Preble's meadow jumping 

mouse4/

36 miles

Badwater to Waltman PacifiCorp Federal 26 miles grizzly bear5/ 26 miles

Billings to Yellowtail NorthWestern Corp Federal 42 miles grizzly bear5/ 42 miles

Birch Creek to Ben Lomond PacifiCorp Federal 55 miles Canada lynx linkage 

habitat7/

14 miles

Blacks Fork to West Vaco PacifiCorp Federal 10 miles grizzly bear5/ 10 miles

Blue Rim Switching Station to

Palisades SW

PacifiCorp Federal 4 miles grizzly bear5/ 4 miles

Blue Rim Switching Station to 

South Trona

PacifiCorp Federal 13 miles grizzly bear5/ 12 miles

Casper North to Dave 

Johnston

PacifiCorp Federal 31 miles grizzly bear5/ 2 miles

Preble's meadow jumping 

mouse4/

16 miles

Casper North to Midwest PacifiCorp Private 40 miles grizzly bear5/ 20 miles

Casper to Casper North PacifiCorp Private 2 miles grizzly bear5/ 2 miles

Dave Johnston to Difficulty PacifiCorp Federal 44 miles black-footed ferret 10J 

population

17 miles

Preble's meadow jumping 

mouse4/

21.6 miles

Dave Johnston to Laramie 

River

Basin Electric Power 

Coop

Federal 77 miles Preble's meadow jumping 

mouse4/

77 miles

Dave Johnston to Stegall Western Area Power 

Administration

Private 126 miles Preble's meadow jumping 

mouse4/

119 miles

Difficulty to Miners PacifiCorp Federal 42 miles black-footed ferret 10J 

population

42 miles

Fish Creek to Tap PacifiCorp Private 0.1 miles grizzly bear5/ 0.1 miles
Biological Assessment Gateway West Transmission Line Project

March 2013 71

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Transmission 

Lines

Frannie to Garland PacifiCorp Federal 13 miles grizzly bear5/ 13 miles

Garland to Oregon Basin PacifiCorp Federal 42 miles grizzly bear5/ 42 miles

Grass Creek to Thermopolis PacifiCorp Federal 23 miles grizzly bear5/ 23 miles

Jim Bridger to Borah PacifiCorp Federal 340 miles Canada lynx linkage 

habitat7/

44 miles

grizzly bear5/ 124 miles

Jim Bridger to Goshen PacifiCorp Federal 226 miles Canada lynx linkage 

habitat7/

47 miles

grizzly bear5/ 209 miles

Jim Bridger to Kiport PacifiCorp Federal 234 miles Canada lynx linkage 

habitat7/

44 miles

grizzly bear5/ 124 miles

Jim Bridger to Rock Springs PacifiCorp Federal 33 miles grizzly bear5/ 13 miles

Kinport to Goshen PacifiCorp Tribal 40 miles grizzly bear5/ 25 miles

Laramie River Sidney to 

Sidney

Tri State Generation & 

Transmission 

Association Inc.

Federal 123 miles Preble's meadow jumping 

mouse4/

60 miles

Laramie River to Stegall Tri State Generation & 

Transmission 

Association Inc.

Private 57 miles Preble's meadow jumping 

mouse4/

53 miles

Laramie River to Story Basin Electric Power 

Coop

Private 173 miles Preble's meadow jumping 

mouse4/

93 miles

Laramie River to Tap Basin Electric Power 

Coop

Federal 80 miles Preble's meadow jumping 

mouse4/

80 miles

Lost River to Spar Canyon Bonneville Power 

Administration

Federal 53 miles Canada lynx linkage 

habitat7/

10 miles

Mansface to Blue Rim 

Switching Station

PacifiCorp Federal 4 miles grizzly bear5/ 4 miles

Midwest to Buffalo PacifiCorp Federal 67 miles grizzly bear5/ 10 miles

Miners to Platte PacifiCorp Federal 31 miles black-footed ferret 10J 

population

20 miles

Monument SW to Blacks Fork PacifiCorp Federal 7 miles grizzly bear5/ 7 miles

Monument SW to Naughton PacifiCorp Federal 30 miles grizzly bear5/ 2 miles

Monument SW to Shute Creek PacifiCorp Federal 16 miles grizzly bear5/ 16 miles

Mustang to Jim Bridger PacifiCorp Federal 73 miles grizzly bear5/ 73 miles
Biological Assessment Gateway West Transmission Line Project

March 2013 72

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Transmission 

Lines

Naughton to Treasureton PacifiCorp Federal 78 miles grizzly bear5/ 9 miles

Canada lynx linkage 

habitat7/

31 miles

Oregon Basin to Grass Creek PacifiCorp Federal 41 miles grizzly bear5/ 41 miles

Palisades SW to West Vaco PacifiCorp Federal 11 miles grizzly bear5/ 11 miles

Peterson Flats to Tap NorthWestern Corp. Federal 38 miles Canada lynx linkage 

habitat7/

18 miles

Point of Rocks to Jim Bridger PacifiCorp Federal 8 miles grizzly bear5/ 5 miles

Riverton to Casper North PacifiCorp Federal 110 miles grizzly bear5/ 110 miles

Riverton to Thermopolis PacifiCorp Federal 51 miles grizzly bear5/ 51 miles

Canada lynx linkage 

habitat7/

10 miles

Rock Springs to Atlantic City PacifiCorp Federal 69 miles grizzly bear5/ 69 miles

Rock Springs to Firehole PacifiCorp Federal 7 miles grizzly bear5/ 4 miles

Rock Springs to Palisades SW PacifiCorp Federal 13 miles grizzly bear5/ 13 miles

Sheridan to Buffalo PacifiCorp Private 40 miles grizzly bear5/ 7 miles

South Trona to Monument SW PacifiCorp Federal 19 miles grizzly bear5/ 15 miles

Spence to Dave Johnston PacifiCorp Federal 70 miles grizzly bear5/ 41 miles

Preble's meadow jumping 

mouse4/

16 miles

Spence to Mustang PacifiCorp Federal 77 miles grizzly bear5/ 77 miles

Tap to Ault Tri State Generation & 

Transmission 

Association Inc.

Federal 30 miles Preble's meadow jumping 

mouse4/

8 miles

Teckla to Antelope PacifiCorp Federal 2 miles Preble's meadow jumping 

mouse4/

3 miles

Thermopolis to Badwater PacifiCorp Federal 2 miles grizzly bear5/ 44 miles

Canada lynx linkage 

habitat7/

10 miles

Unknown3/ to Frannie PacifiCorp Federal 55 miles grizzly bear5/ 55 miles

Canada lynx linkage 

habitat7/

7 miles

Waltman to Spence PacifiCorp Federal 40 miles grizzly bear5/ 40 miles

Wyopo to Riverton PacifiCorp Federal 20 miles grizzly bear5/ 20 miles

Yellowcake to Dave Johnston PacifiCorp Private 20 miles Preble's meadow jumping 

mouse4/

20 miles

Yellowtail to Custer Western Area Power 

Administration

Federal 62 miles grizzly bear5/ 32 miles
Biological Assessment Gateway West Transmission Line Project

March 2013 73

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Transmission 

Lines

Yellowtail to Goose Creek SW 

Station

PacifiCorp Tribal 60 miles grizzly bear5/ 60 miles

Natural Gas 

Pipelines

Unknown Bitter Creek Pipelines Unknown8/ 1 mile grizzly bear5/ 1 mile

Unknown Cheyenne Light Fuel & 

Power Co.

Unknown8/ 32 miles Preble's meadow jumping 

mouse4/

32 miles

Unknown Colorado Interstate 

Gas Co

Federal 1,116 miles black-footed ferret 10J 

population

111 miles

Canada lynx linkage 

habitat7/

10 miles

Preble's meadow jumping 

mouse4/

254 miles

grizzly bear5/ 526 miles

Unknown DCP Midstream Federal 177 miles grizzly bear5/ 108 miles

Unknown EnCana Oil & Gas 

(USA) Inc.

Unknown8/ 45 miles grizzly bear5/ 45 miles

Unknown Energy West Wyoming Unknown8/ 161 miles grizzly bear5/ 161 miles

Unknown Fort Union Gas 

Gathering LLC

State 54 miles Preble's meadow jumping 

mouse4/

1 mile

Private Preble's meadow jumping 

mouse4/

29 miles

Unknown8/ Preble's meadow jumping 

mouse4/

24 miles

Unknown Gas Transmission 

Northwest Corp 

Federal 48 miles Canada lynx linkage 

habitat7/

48 miles

Snake River species 1 mile

Unknown Intermountain Gas Co. Private 7 miles grizzly bear5/ 4 miles

Unknown8/ grizzly bear5/ 2 miles

Unknown Kinder Morgan Inc. Federal 191 miles black-footed ferret 10J 

population

44 miles

Preble's meadow jumping 

mouse4/

75 miles

grizzly bear5/ 23 miles

Unknown Kinder Morgan 

Interstate Gas 

Transmission LLC

Federal 666 miles Canada lynx linkage 

habitat7/

5 miles

Preble's meadow jumping 

mouse4/

355 miles

grizzly bear5/ 277 miles
Biological Assessment Gateway West Transmission Line Project

March 2013 74

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Natural Gas 

Pipelines

Unknown Kinder Morgan 

Intrastate Casper 

Division

Federal 650 miles black-footed ferret 10J 

population

72 miles

grizzly bear5/ 473 miles

Canada lynx linkage 

habitat7/

8 miles

Preble's meadow jumping 

mouse4/

54 miles

Unknown MGTC Inc. State 13 miles Preble's meadow jumping 

mouse4/

0.4 mile

Private Preble's meadow jumping 

mouse4/

8 miles

Unknown8/ grizzly bear5/ 5 miles

Unknown MIGC LLC Federal 99 miles Preble's meadow jumping 

mouse4/

99 miles

Unknown Northern Natural Gas 

Co.

Federal 69 miles Snake River species 1 mile

Unknown Northwest Pipeline 

Corp.

Federal 267 miles Canada lynx linkage 

habitat7/

89 miles

grizzly bear5/ 101 miles

Snake River species 3 miles

Unknown Northwest Pipeline 

Corp.

Federal 32 miles Bruneau hot springsnail 0.6 mile

Unknown Overthrust Pipeline 

Co.

Federal 163 miles grizzly bear5/ 50 miles

Unknown Public Service Co. of 

Colorado

Unknown8/ 2 miles Preble's meadow jumping 

mouse4/

2 miles

Unknown Questar Gas Co. Private 2 miles grizzly bear5/ 2 miles

Unknown Questar Pipeline Co. Federal 249 miles Preble's meadow jumping 

mouse4/

2 miles

grizzly bear5/ 57 miles

Canada lynx habitat 1 mile

Unknown Rockies Express 

Pipeline LLC

Unknown8/ 6 miles Preble's meadow jumping 

mouse4/

6 miles

Unknown Southern Star Central 

Gas Pipeline Inc.

Federal 165 miles black-footed ferret 10J 

population

44 miles

Preble's meadow jumping 

mouse4/

76 miles

grizzly bear5/ 14 miles

Unknown Trailblazer Pipeline 

Co.

Unknown8/ 6 miles Preble's meadow jumping 

mouse4/

6 miles
Biological Assessment Gateway West Transmission Line Project

March 2013 75

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Natural Gas 

Pipelines

Unknown Viking Gas 

Transmission Co.

Federal 56 miles Snake River species 0.6 mile

Unknown WestGas InterState 

Inc.

Unknown8/ 8 miles Preble's meadow jumping 

mouse4/

8 miles

Unknown Williston Basin 

Interstate Pipeline Co.

Unknown8/ 345 miles Canada lynx linkage 

habitat7/

9 miles

grizzly bear5/ 336 miles

Unknown Wyoming Interstate 

Co. Ltd.

Federal 659 miles black-footed ferret 10J 

population

66 miles

Preble's meadow jumping 

mouse4/

467 miles

grizzly bear5/ 79 miles

Oil Pipelines

Express Kinder Morgan Inc. Private 221 miles grizzly bear5/ 4 miles

Canada lynx linkage 

habitat7/

9 miles

Unknown8/ grizzly bear5/ 207 miles

Platte Kinder Morgan Inc. Private 143 miles Preble's meadow jumping 

mouse4/

33 miles

State Preble's meadow jumping 

mouse4/

4 miles

Unknown8/ Preble's meadow jumping 

mouse4/

98 miles

Pacific Energy Partners Sinclair/Salt Lake Core 

System

Federal 358 miles black-footed ferret 10J 

population

15 miles

Preble's meadow jumping 

mouse4/

1 mile

grizzly bear5/ 24 miles

Private black-footed ferret 10J 

population

28 miles

Preble's meadow jumping 

mouse4/

0.5 mile

grizzly bear5/ 47 miles

State black-footed ferret 10J 

population

3 miles

grizzly bear5/ 3 miles

Unknown8/

black-footed ferret 10J 

population

16 miles

Preble's meadow jumping 

mouse4/

87 miles
Biological Assessment Gateway West Transmission Line Project

March 2013 76

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Linear Projects

Oil Pipelines

Suncor Energy Inc Suncor Unknown8/ 87 miles Preble's meadow jumping 

mouse4/

87 miles

True Oil LLC Butte Unknown8/ 30 miles Preble's meadow jumping 

mouse4/

30 miles

Major Roads

Interstate Highways NA Federal 2,176 miles black-footed ferret 10J 

population

69 miles

Canada lynx linkage 

habitat7/

78 miles

Preble's meadow jumping 

mouse4/

608 miles

grizzly bear5/ 1,224 miles

Snake River species 33 miles

U.S. Highways NA Federal 3,350 miles black-footed ferret 10J 

population

70 miles

Canada lynx linkage 

habitat7/

417 miles

Preble's meadow jumping 

mouse4/

336 miles

grizzly bear5/ 2,430 miles

Bull trout critical habitat 0.2 mile

Snake River species 51 miles

State Highways/Routes NA State 3,599 miles black-footed ferret 10J 

population

174 miles

Canada lynx linkage 

habitat7/

384 miles

Preble's meadow jumping 

mouse4/

886 miles

grizzly bear5/ 1,969 miles

Bruneau hot springsnail 0.7 mile

Bull trout critical habitat 27 miles

Snake River species 34 miles

Other Major Roads NA -- 1,314 miles black-footed ferret 10J 

population

97 miles

Canada lynx linkage 

habitat7/

34 miles

Preble's meadow jumping 

mouse4/

410 miles

grizzly bear5/ 733 miles

Bull trout critical habitat 3 miles

Snake River species 0.5 mile
Biological Assessment Gateway West Transmission Line Project

March 2013 77

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Wind Farms

Campbell Hill Wind Three Buttes Wind, 

LLC

Federal 13,560 acres Preble's meadow jumping 

mouse4/

13,560 acres

Camp Reed Wind Farm RP Wind ID LLC Federal 900 acres slickspot peppergrass 

potential habitat6/

65 acres

Cassia Gulch Wind Park Cassia Gulch Wind 

Park LLC

Private 204 acres slickspot peppergrass 

potential habitat6/

42 acres

Cassia Wind Farm Cassia Wind Farm 

LLC

Private 64 acres slickspot peppergrass 

potential habitat6/

0 acres

Dunlap Wind Farm Rocky Mountain 

Power/PacifiCorp

Federal 16,608 acres black-footed ferret 10J 

population

16,608 acres

Foote Creek I AES Wind Generation 

Inc.

Federal 265 acres black-footed ferret 10J 

population

265 acres

Foote Creek II AES Wind Generation 

Inc.

State 40 acres black-footed ferret 10J 

population

40 acres

Foote Creek III AES Wind Generation 

Inc.

Federal 279 acres black-footed ferret 10J 

population

279 acres

Foote Creek IV AES Wind Generation 

Inc.

Federal 170 acres black-footed ferret 10J 

population

170 acres

Glenrock Wind Energy Project PacifiCorp Private 15,111 acres Preble's meadow jumping 

mouse4/

15,111 acres

Goshen II BP Wind Energy North 

America Inc.

Private 8,668 acres grizzly bear5/ 8,668 acres

Happy Jack Wind Happy Jack 

Windpower LLC

Private 1,028 acres Preble's meadow jumping 

mouse4/

1,028 acres

High Plains Wind (WY) PacifiCorp Federal 4,231 acres black-footed ferret 10J 

population

4,231 acres

Preble's meadow jumping 

mouse4/

4,231 acres

Horse Butte Wind Farm Utah Associated 

Municipal Power 

System

Federal 5,734 acres grizzly bear5/ 5,734 acres

Hot Springs Windfarm Hot Springs Windfarm 

LLC

Private 208 acres slickspot peppergrass 

potential habitat6/

70 acres

McFadden Ridge Wind PacifiCorp Federal 10,592 acres black-footed ferret 10J 

population

9,522 acres

Preble's meadow jumping 

mouse4/

8,510 acres

Medicine Bow (Prpa) Platte River Power 

Authority

Private 193 acres black-footed ferret 10J 

population

193 acres
Biological Assessment Gateway West Transmission Line Project

March 2013 78

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Wind Farms

Oregon Trail Wind Park RP Wind ID LLC Private 1,201 acres slickspot peppergrass 

potential habitat6/

155 acres

Paynes Ferry Wind Park RP Wind ID LLC Private 1,796 acres slickspot peppergrass 

potential habitat6/

203 acres

Pilgrim Stage Station Wind 

Park

RP Wind ID LLC Private 1,128 acres slickspot peppergrass 

potential habitat6/

107 acres

Rock Creek I (SEENGR) SeaWest Energy 

Group, Inc.

Federal area 

unknown8/

black-footed ferret 10J 

population

area unknown8/

Rock River I LLC AES Wind Generation 

Inc.

Federal 1,211 acres black-footed ferret 10J 

population

1,211 acres

Rolling Hills Wind PacifiCorp Private area 

unknown8/ Preble's meadow jumping mouse4/

area unknown8/

Salmon Falls Wind Farm RP Wind ID LLC Private 1,274 acres slickspot peppergrass 

potential habitat6/

650 acres

Sawtooth Wind Farm Powerworks Private 1496 acres slickspot peppergrass 

potential habitat6/

2 acres

Seven Mile Hill Wind PacifiCorp Federal 8,968 acres black-footed ferret 10J 

population

8,968 acres

Silver Sage Wind Farm Silver Sage 

Windpower LLC

Private 2,584 acres Preble's meadow jumping 

mouse4/

2,584 acres

Thousand Springs Wind Park RP Wind ID LLC Private 1,244 acres slickspot peppergrass 

potential habitat6/

3 acres

Top of The World Windpower 

Project

Top of The World Wind 

Energy LLC/Duke 

Energy NA

Federal 18,152 acres Preble's meadow jumping 

mouse4/

18,152 acres

Tuana Gulch Wind Park RP Wind ID LLC Private 486 acres slickspot peppergrass 

potential habitat6/

19 acres

Warren Air Force Wind Amec Wind Energy Ltd Federal 21 acres Preble's meadow jumping 

mouse4/

21 acres

Wolverine Creek Wind Invenergy Federal 10,893 acres grizzly bear5/ 10,893 acres

Yahoo Creek Wind Park RP Wind ID LLC Private 1,915 acres slickspot peppergrass 

potential habitat6/

451 acres

Oil-fired Power 

Plants

Blacks Fork Gas Processing 

Plant

Questar Gas 

Management Co.

Federal area 

unknown8/ grizzly bear5/ area unknown8/

area 

unknown8/

black-footed ferret 10J 

population

area unknown8/

Grant Village Clark Fork & Blackfoot, 

LLC

Federal area 

unknown8/ grizzly bear5/ area unknown8/

Lake Diesel Clark Fork & Blackfoot, 

LLC

Federal area 

unknown8/ grizzly bear5/ area unknown8/
Biological Assessment Gateway West Transmission Line Project

March 2013 79

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Oil-fired Power 

Plants

Old Faithful Clark Fork & Blackfoot, 

LLC

Federal area 

unknown8/ grizzly bear5/ area unknown8/

area 

unknown8/ Canada lynx linkage habitat7/

area unknown8/

Natural Gas-fired 

Power Plants

Labarge Shute Cogeneration ExxonMobil Corp. Federal area 

unknown8/ grizzly bear5/ area unknown8/

Coal-fired Power 

Plants

Dave Johnston PacifiCorp Private area 

unknown8/ Preble's meadow jumping mouse4/

area unknown8/

Jim Bridger PacifiCorp Federal area 

unknown8/ grizzly bear5/ area unknown8/

Laramie River Basin Electric Power 

Cooperative

Private area unknown Preble's meadow jumping 

mouse4/

area unknown8/

Platte River Species area unknown8/

SF Phosphates Limited Co. SF Phosphates, Ltd. 

Co.

Private area 

unknown8/ grizzly bear5/ area unknown8/

Hydropower 

Plants

Alcova U.S. Bureau of 

Reclamation

Federal area 

unknown8/ Platte River Species area unknown8/

American Falls Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Anderson Ranch U.S. Bureau of 

Reclamation

Federal 4,601 acre 

reservoir

Bull trout critical habitat area unknown8/

Arrowrock Arrowrock 

Hydroelectric Project

Federal 3,049 acre 

reservoir

Bull trout critical habitat area unknown8/

Bliss Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Brownlee Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

C J Strike Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Fontenelle U.S. Bureau of 

Reclamation

Federal area 

unknown8/ Colorado River species area unknown8/

Fremont Canyon U.S. Bureau of 

Reclamation

Federal area 

unknown8/

Platte River Species area unknown8/

Gem State Idaho Falls, ID (City of) Federal area 

unknown8/ Snake River Species area unknown8/

Glendo U.S. Bureau of 

Reclamation

Federal area 

unknown8/ Platte River Species area unknown8/

Hells Canyon Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/
Biological Assessment Gateway West Transmission Line Project

March 2013 80

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Hydropower 

Plants

Kortes US Bureau of 

Reclamation

Federal area 

unknown8/ Platte River Species area unknown8/

Lower Malad (IDPC) Idaho Power Co. Federal area 

unknown8/

Snake River Species area unknown8/

Lower Salmon Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Milner Hydro Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Minidoka US Bureau of 

Reclamation

Federal area 

unknown8/ Snake River Species area unknown8/

Oxbow (OR) Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Palisades (ID) U.S. Bureau of 

Reclamation

Federal area 

unknown8/ Snake River Species area unknown8/

Seminoe U.S. Bureau of 

Reclamation

Federal area 

unknown8/ Platte River Species area unknown8/

Shoshone Falls Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Swan Falls Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Twin Falls (ID) Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Upper Salmon Falls A Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Upper Salmon Falls B Idaho Power Co. Federal area 

unknown8/ Snake River Species area unknown8/

Oil and Gas 

Leases

Multiple Projects Various Federal 935,484 

acres

black-footed ferret 10J 

population

215,830 acres

Preble's meadow jumping 

mouse4/

272,040 acres

grizzly bear5/ 6,933,531 acres

Canada lynx habitat 339,915 acres

Canada lynx linkage 

habitat7/

595,090 acres

Colorado River species 203,381 acres

Snake River Species 324 acres

Platte River Species 70,943 acres

State 94,285 acres black-footed ferret 10J 

population

6,531 acres
Biological Assessment Gateway West Transmission Line Project

March 2013 81

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Oil and Gas 

Leases

Multiple Projects Various State 94,285 acres Preble's meadow jumping 

mouse4/

14,388 acres

grizzly bear5/ 82,199 acres

Canada lynx habitat 565 acres

Canada lynx linkage 

habitat7/

2,336 acres

Tribal 15,252 acres grizzly bear5/ 0.4 acres

Canada lynx linkage 

habitat7/

288 acres

Private 625,202 

acres

black-footed ferret 10J 

population

60,348 acres

Preble's meadow jumping 

mouse4/

1,144,967 acres

grizzly bear5/ 1,195,583 acres

Canada lynx habitat 58,063 acres

Canada lynx linkage 

habitat7/

101,665 acres

Trona Mining

Multiple Projects NA Federal 753,780 

acres

black-footed ferret 10J 

population

406 acres

Preble's meadow jumping 

mouse4/

406 acres

grizzly bear5/ 649,059 acres

Colorado River species 81,564 acres

Multiple Projects NA State 29,527 acres black-footed ferret 10J 

population

207 acres

Preble's meadow jumping 

mouse4/

207 acres

grizzly bear5/ 24,267 acres

Multiple Projects NA Tribal -- -- --

Multiple Projects NA Private 319,533 

acres

black-footed ferret 10J 

population

5,921 acres

Preble's meadow jumping 

mouse4/

5,921 acres

grizzly bear5/ 272,113 acres

Coal Deposits

Multiple Projects Various Federal 939,104 

acres

black-footed ferret 10J 

population

103,127 acres

Preble's meadow jumping 

mouse4/

6,658 acres
Biological Assessment Gateway West Transmission Line Project

March 2013 82

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Coal Deposits

Multiple Projects Various Federal 939,104 

acres

grizzly bear5/ 168,233 acres

Colorado River species 2,538 acres

Platte River Species 3,369 acres

Multiple Projects Various State 287,759 

acres

black-footed ferret 10J 

population

30,520 acres

Preble's meadow jumping 

mouse4/

25,478 acres

grizzly bear5/ 949 acres

None NA Tribal -- -- --

Multiple Projects Various Private 277,643 

acres

black-footed ferret 10J 

population

274,777 acres

Preble's meadow jumping 

mouse4/

267,299 acres

grizzly bear5/ 188,724 acres

Coal Leases

Multiple Projects Various Federal 48,869 acres black-footed ferret 10J 

population

14,886 acres

Preble's meadow jumping 

mouse4/

1,435 acres

grizzly bear5/ 16,169 acres

Colorado River species 1,749 acres

Platte River Species 319 acres

Multiple Projects Various State 740 acres black-footed ferret 10J 

population

644 acres

Preble's meadow jumping 

mouse4/

2 acres

grizzly bear5/ 0.3 acres

None NA Tribal -- -- --

Multiple Projects Various Private 38,600 acres black-footed ferret 10J 

population

1,445 acres

Preble's meadow jumping 

mouse4/

9,390 acres

grizzly bear5/ 1,953 acres

Oil and Gas 

Fields 9/

Multiple Projects Various Federal 729,385 

acres

black-footed ferret 10J 

population

1,854 acres

Preble's meadow jumping 

mouse4/

24,265 acres

grizzly bear5/ 564,457 acres

Canada lynx habitat 26,342 acres

Canada lynx linkage 

habitat7/

124 acres
Biological Assessment Gateway West Transmission Line Project

March 2013 83

Table 3-16. Existing Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction 1/

Project 

Footprint2/

Species Range 

Overlapped

Project Footprint 

within Species 

Range2/

Non-Linear Projects

Oil and Gas 

Fields 9/

Multiple Projects Various Federal 729,385 

acres

Colorado River species 24,449 acres

Platte River Species 3,971 acres

State 92,049 acres black-footed ferret 10J 

population

860 acres

Preble's meadow jumping 

mouse4/

36,229 acres

grizzly bear5/ 44,563 acres

Canada lynx habitat 1,442 acres

Canada lynx linkage 

habitat7/

133 acres

Tribal 15,235 acres grizzly bear5/ 15,252 acres

Private 620,683 

acres

black-footed ferret 10J 

population

6,951 acres

Preble's meadow jumping 

mouse4/

254,693 acres

grizzly bear5/ 217,513 acres

Canada lynx habitat 7,231 acres

Canada lynx linkage 

habitat7/

922 acres

1/ Jurisdiction was determined through examination of land ownership as well as project action. Projects that would trigger a federal nexus were classified as 

"Federal" jurisdiction projects.

2/ These acreages correspond to raw acreages within the species range/Analysis-Area, and do not necessarily directly correspond to acres within suitable habitat 

(i.e., there can be extensive areas of unsuitable habitat within a species range, and complete habitat information is not available at the level assessed for cumulative 

effects).

3/ Data did not provide information on proposed point of origin.

4/ Analysis of Preble's meadow jumping mouse habitat was restricted to the state of Wyoming.

5/ Grizzly bear habitat analysis extent consists of habitat for the Greater Yellowstone Area (GYA) population and includes the GYA BMU, and suitable habitat areas 

within this extent.

6/ Slickspot peppergrass potential habitat includes data for both areas of occupied and potential habitat.

7/ Canada lynx linkage areas is a generalized area around the directional linkage areas identified by cooperative agreement between the U.S. Department of 

Agriculture Forest Service, Bureau of Land Management, and U.S. Fish and Wildlife Service in 2000 and published in 2003.

8/ The available data for this project was a point file with no area attributes; therefore, no Project Footprint or area in species range was calculated.
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These areas represent existing and potential utilization. Because proposed utilization is 

not known at this time, reasonable and foreseeable impacts to the species could not be 

directly determined for this analysis. Furthermore, these acreages correspond to raw 

acreages within the species range/Analysis Area, and do not necessarily directly 

correspond to acres within suitable habitat (i.e., there can be extensive areas of 

unsuitable habitat within a species range, and complete habitat information is not 

available at the level assessed for cumulative effects). 

Reasonably foreseeable projects occurring within the species ranges are listed in 

Table 3-17. Wind generation facilities are the dominant proposed projects that occur on 

land other than federal. Slickspot peppergrass habitat would be impacted by 8 of the 13 

proposed wind projects, grizzly bear habitat occurs in 4, and Preble’s meadow jumping 

mouse and Canada lynx linkage habitat each occur in one proposed wind project. 

Preble’s meadow jumping mouse is the only species with habitat crossed by the 

proposed transmission lines. Wind generation projects generally do not occur in 

suitable habitat for Ute ladies’-tresses, and blowout penstemon’s range does not extend 

into Idaho. However, as these plants could occur in areas considered for the Project 

and additional potential project activity, there is a possibility of cumulative impacts to the 

species.
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Table 3-17. Proposed (i.e., Reasonably Foreseaable) Projects Considered within the Cumulative Effects Analysis

Project Type Project Name Project Owner Jurisdiction1/

Project 

Footprint2/

Species Range 

Overlapped

Project 

Footprint 

within Species 

Range 2/

Linear Projects

Transmission 

Lines

Ault to Cheyenne Western Area Power 

Administration

Private 35 miles Preble's meadow 

jumping mouse4/

9 miles

Top of The World 

Windpower Project to 

Windstar

Duke Energy Corp. Private 6 miles Preble's meadow 

jumping mouse4/

6 miles

Unknown3/ to Campbell 

Hill

PacifiCorp Private 12 miles Preble's meadow 

jumping mouse4/

12 miles

Non-Linear Projects

Wind Farms

Black Canyon Wind Black Canyon LLC Private 84 acres grizzly bear5/ 84 acres

Cold Springs Wind Farm 

(ID)

Aegis Renewables LLC Private 264 acres slickspot peppergrass 

potential habitat6/

64 acres

slickspot peppergrass 

critical habitat7/

12 acres

Hammett Hill Windfarm Aegis Renewables LLC Private 495 acres slickspot peppergrass 

potential habitat6/

371 acres

Mainline Windfarm Aegis Renewables LLC Private 1,476 acres slickspot peppergrass 

potential habitat6/

636 acres

Mission Creek Wind 

Project

Sagebrush Energy LLC Private 2,051 acres grizzly bear5/ 2,051 acres

Canada lynx linkage 

habitat8/

2,051 acres

Pathfinder Wind Pathfinder Renewable 

Wind Energy, LLC

Private area 

unknown9/

Preble's meadow 

jumping mouse4/

area unknown9/

Ryegrass Wind Farm Aegis Renewables LLC Private 1,444 acres slickspot peppergrass 

potential habitat6/

854 acres

slickspot peppergrass 

critical habitat7/

192 acres

Schwendiman Wind Schwendiman Wind LLC Private 246 acres grizzly bear5/ 246 acres

Two Ponds Windfarm Aegis Renewables LLC Private 1,636 acres slickspot peppergrass 

potential habitat6/

1 acres

Desert Meadow Wind 

Farm

Aegis Renewables LLC Private 1,829 acres slickspot peppergrass 

potential habitat6/

837 acres
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Table 3-17. Proposed (i.e., Reasonably Foreseaable) Projects considered within the Cumulative Effects Analysis (continued)

Project Type Project Name Project Owner Jurisdiction1/

Project 

Footprint2/

Species Range 

Overlapped

Project 

Footprint 

within Species 

Range 2/

Wind Farms

High Mesa Wind Project High Mesa Energy LLC Private 1,304 acres slickspot peppergrass 

potential habitat6/

497 acres

Magic Wind Magic Wind LLC Private 1,328 acres slickspot peppergrass 

potential habitat6/

156 acres

Idaho Falls (Bone area) Idatherm Private area 

unknown9/ grizzly bear5/ area unknown9/

1/ Jurisdiction was determined through examination of land ownership as well as project action. Projects that would trigger a federal nexus were classified as 

"Federal" jurisdiction projects and were not included in the analysis of "Proposed" actions.

2/ These acreages correspond to raw acreages within the species range/Analysis-Area, and do not necessarily directly correspond to acres within suitable habitat 

(i.e., there can be extensive areas of unsuitable habitat within a species range, and complete habitat information is not available at the level assessed for 

cumulative effects).

3/ Data did not provide information on proposed point of origin.

4/ Analysis of Preble's meadow jumping mouse habitat was restricted to the state of Wyoming.

5/ Grizzly bear habitat analysis extent consists of habitat for the Greater Yellowstone Area (GYA) population and includes the GYA BMU, and suitable habitat 

areas within this extent.

6/ Slickspot peppergrass potential habitat includes data for both areas of occupied and potential habitat.

7/ Slickspot peppergrass critical habitat includes data for proposed critical habitat area.

8/ Canada lynx linkage areas is a generalized area around the directional linkage areas identified by cooperative agreement between the U.S. Department of 

Agriculture Forest Service, Bureau of Land Management, and U.S. Fish and Wildlife Service in 2000 and published in 2003.

9/ The available data for this project was a point file with no area attributes; therefore, no Project Footprint or area in species range was calculated.
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4 IMPACTS

This section describes the direct, indirect, and cumulative effects of the proposed action 

on listed species within the Action Area. Direct impacts are immediate effects of an 

action. Indirect impacts are those that result from the action and occur later in time but 

are still reasonably certain to occur. Cumulative impacts are effects from state and 

private activities that are reasonably certain to occur within the action area of the federal 

action subject to consultation; future federal actions that are unrelated to the proposed 

action are not considered in this section because they are addressed in a separate 

NEPA process and require separate consultation pursuant to Section 7 of the ESA (see 

Chapter 4 of the EIS). In order to form a frame of reference for the analysis of impacts 

below, the numbers of acres of various habitat types impacted within the Action Area

during Project construction and operation are presented below (Table 4-1).

Table 4-1. Acres of Vegetation Types that Would Be Affected During Construction and 

Operations

Vegetation Type

Acres of Disturbance 

during Construction

Acres of Disturbance 

during Operation

Grassland 2,960 327

Shrubland1/ 11,716 1,591

Forest/Woodland2/ 1,494 1,245

Wetland/Riparian 198 28

Other Cover Type3/ 3,559 439

Total4/ 19,925 3,636

1/ “Shrubland” includes sagebrush, saltbrush, greasewood, and dwarf shrublands.

2/ “Forest/Woodland” includes conifer and deciduous forests as well as juniper woodlands

3/ “Other Cover Type” includes agricultural, disturbed/developed areas, open water, as well as areas with no 

vegetation.

4/ Columns may not sum exactly due to rounding.

4.1 Colorado River Species

4.1.1 Direct and Indirect Effects

The four endangered fish addressed under the UCEFRP (i.e., Colorado pikeminnow, 

razorback sucker, humpback chub, and bonytail chub, as well as their critical habitat) all 

occur far downstream from the Action Area (Figure 3-1); with the closest known 

occurrence located approximately 78 miles from the Project Area. Recovery of 

Colorado River fishes depends on the protection of instream flow and to protect this 

important resource for recovery, all water depletions of the system must be addressed 

as to their amount and potential for reducing that protected flow. Project-related actions 

that could affect local or near-stream conditions would have no effect on these far 

downstream habitats because the system where these species reside would be 

unchanged from local conditions, but the Project would have associated withdrawals of 

water from the system. In this manner then, and because the Project would use water 

that may be drawn in part from the Colorado River system for dust abatement/control, 

the requirements found in the UCEFRP regarding water withdrawals would apply to this 

Project.
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The Proponents estimate that Project-related water use during construction for Segment 

3 and half of the estimated usage for Segment 4 (because approximately half of 

Segment 4 lies in the Colorado River basin) would total 4,795,710 gallons (14.7 acrefeet; see Table D.16-12 of the EIS). Using this estimate and providing for the 

assumption that all of this water could be withdrawn from the Colorado River system 

(which may not be the case given the Proponent-committed conservation measures) 

total depletion within the basin would be no more than 0.3 acre-feet per year. This 

amount is greater than the identified threshold of 0.1 acre-feet per year from the 

UCEFRP, for which a “no effect” determination could be made. However, because the 

Proponents are currently unable to identify all of the future withdrawal locations and 

precise amount per each location, the depletion of 0.3 acre-feet annually from the 

Colorado River basin may affect, and is likely to adversely affect, the Colorado 

pikeminnow, razorback sucker, humpback chub, and bonytail chub; and though 

depletions may affect, they are not likely to adversely affect critical habitats due to 

insignificant effects.

4.1.2 Cumulative Effects

No other proposed projects were identified along the Colorado River basin in the vicinity 

of the Project (see Table 3-17); however, it is anticipated that if any other projects were 

proposed/constructed, they would be required to comply with the requirements of the 

UCEFRP and coordinate or consult with the USFWS if withdrawals exceed 0.1 acre-feet 

per year. This would likely minimize impacts; however, any impacts that do occur would 

add cumulatively to those from Gateway West. 

4.1.3 Critical Habitat

No critical habitat for any of the four endangered Colorado River fish occurs within the 

Action Area, so direct impacts are not anticipated. However, based on the requirements 

of the UCEFRP, and the fact that all necessary water sources have not been identified 

or acquired at this time, the Project may affect, but is not likely to adversely affect critical 

habitat for the Colorado pikeminnow, razorback sucker, humpback chub, and bonytail 

chub.

4.2 Platte River Species

4.2.1 Direct and Indirect Effects

The five listed species addressed under the PRRIP (i.e., pallid sturgeon, interior least 

tern, whooping crane, piping plover, and western prairie fringed orchid, as well as

whooping crane designated critical habitat) all occur far downstream from the Action 

Area (Figure 3-2). Recovery of Platte River species depends on the protection of 

instream flow and to protect this important resource for recovery, all water depletions of 

the system must be addressed as to their amount and potential for reducing that 

protected flow. Project-related actions that could affect local or near-stream conditions 

would have no effect on these far downstream habitats because the system where 

these species reside would be unchanged from local conditions, but the project will 

have associated withdrawals of water from the system. In this manner then, and 

because the Project would use water for dust abatement/control (which may be drawn 
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in part from the Platte River system), the requirements found in the PRRIP regarding 

water withdrawals would apply to this Project.

The Proponents estimate that Project-related water usage during construction along 

Segments 1W and 2, which lie in the Platte River basin, would be 6,016,293 gallons 

(18.5 acre-feet; see Table D.16-12, Appendix D of the EIS). Assuming all of this would 

be drawn from the Platte River system (which may not be the case), this comes to 0.4 

acre-feet per year when divided over the life of the Project (50 years), which is greater 

than the threshold of 0.1 acre-feet per year identified by the PRRIP, above which a no 

effect call is no longer possible and consultation is required. However, because the 

Proponents are currently unable to identify all of the future withdrawal locations and 

precise amount per each location, the depletion of 0.4 acre-feet annually from the Platte 

River basin may affect, and is likely to adversely affect the pallid sturgeon, interior least 

tern, whooping crane, piping plover, and western prairie fringed orchid, and though 

depletions may affect, they are not likely to adversely affect critical habitats due to 

insignificant effects.

4.2.2 Cumulative Effects

No other proposed projects were identified along the Platte River basin in the vicinity of 

the Project (see Table 3-17); however, it is anticipated that if any other projects were 

proposed/constructed, they would be required to comply with the requirements of the 

UCEFRP and coordinate or consult with the USFWS if withdrawals exceed 0.1 acre-feet 

per year. This would likely minimize impacts; however, any impacts that do occur would 

add cumulatively to those from Gateway West. 

4.2.3 Critical Habitat

No critical habitat for whooping crane occurs within the Action Area (Figure 3-2); 

however, as stated above, the Project may affect, but is not likely to adversely affect,

whooping crane critical habitat.

4.3 Mammals

4.3.1 Black-Footed Ferret

4.3.1.1 Direct and Indirect Effects

As discussed above, the only population of black-footed ferret within the action area for 

which consultation is conducted is for the reintroduced 10(j) population in the Shirley 

Basin Area (which is considered a nonessential experimental population).

Quantitative Impacts to Habitat within the Range of the 10(j) Population

During construction, 21 acres of suitable black-footed ferret habitat would be disturbed 

within the 10(j) population’s range along Segment 1W(a), 57 along Segment 1W(c), and 

22 along Segment 2. Following restoration, Project operation would impact 5 acres 

along Segment 1W(a), 5 along Segment 1W(c), and 7 along Segment 2. Even if habitat 

removal takes place where no ferrets are currently present, habitat quality could still be 

reduced, potentially reducing the success of future ferret reintroductions. 
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General Impacts 

Construction and operations of the Project could have direct and indirect impacts on 

black-footed ferrets, including noise and dust disturbance; direct mortality; loss or 

modification of habitat; impacts to their primary prey species (i.e., the prairie dog); and 

increased susceptibility to predation. Project impacts to black-footed ferrets would be 

minimized by micrositing the Project to avoid active prairie dog burrows in proximity to 

the 10(j) reintroduction area that are identified prior to construction. 

Noise and dust disturbance would occur primarily during construction, but also during 

operational maintenance work, from personnel and equipment within the ROW. 

Disturbance could make habitat temporarily unsuitable for black-footed ferrets; to 

minimize this, the Proponents have developed measures within their Traffic and 

Transportation Management Plan to control dust near construction activities. This plan 

also includes measures to control traffic (both existing and Project-related) near 

construction activities, to reduce the likelihood of vehicular related mortality of wildlife 

during construction. The presence of vehicles during construction and operations would 

also pose a risk of death to black-footed ferrets if they are struck. Impacts from 

disturbance and vehicle collisions could be compounded beyond direct Project impacts 

by the increased unauthorized use of Project roads by the public during operation. In 

order to minimize this risk, the Proponents would install and maintain gates at potential 

access points, thereby limiting the access of unauthorized vehicles. 

Increased human and vehicular presence in the Action Area could result in an increased 

fire risk, which could alter black-footed ferret habitat (e.g., fires can be started due to the 

heat generated by vehicles igniting the grass along roads). The risk of this would be 

minimized by controlling public access to Project roads during construction (TRANS-5) 

and by installing gates to control access during operation (OM-6). 

Impacts to prairie dogs during construction and operations would be similar to impacts 

to black-footed ferrets, and would include disturbance, mortality, modification of habitat, 

destruction of burrows, and increased predation pressure. Due to EPMs that would 

apply to this and other species, the Project is not expected to result in population level 

effects to prairie dogs within the Action Area (see the assessment of impacts to prairie

dogs found in Section 3.11 of the EIS). Therefore, black-footed ferrets are not expected 

to experience a significant loss of prey availability. 

The Project would not likely serve as a barrier to the black-footed ferret’s movement, 

because these animals naturally occupy open habitat types and so they are unlikely to 

be hesitant to cross the ROW, and the towers and lines would not physically block 

movement. However, predation pressure on black-footed ferrets could increase due to 

the presence of transmission towers in its habitat, due to their becoming an attractant to 

raptor and ravens as nesting and perching structures (Gilmer and Wiehe 1977; Knight 

and Kawashima 1993; Steenhof et al. 1993; Connelly et al. 2004; Manzer and Hannon 

2005; Coates and Delehanty 2010). This consolidation of birds of prey along 

transmission lines could result in an increase of predation on prey animals that use 

habitats surrounding the transmission line, including black-footed ferrets. The effect of 

increased raptor and raven predation rates would be most prominent where the Project 

is located in areas that do not already contain other tall structures, such as existing 
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transmission lines or trees. Approximately 99 percent of the portion of the Project 

located in black-footed ferret habitat is located adjacent to (within 1 mile of) existing 

transmission lines that already serve as nesting and perching habitats for raptors and 

ravens. In these areas, the Project could cumulatively add to the numbers of raptors 

and ravens that are already utilizing existing transmission lines in the general area. In 

the remaining areas where the Project would not be collocated with existing lines (i.e.,1 

percent of the length), it could create new nesting and perching opportunities. To 

reduce the effects of the Project on raptor/raven predation pressures, the Agencies 

would require EPM TESWL-1 on federally managed lands, and the Proponents have 

indicated that they would also apply this EPM to certain applicable state/private lands 

(see Table 2.7-1 in Chapter 2):

TESWL-1 H-frame structures shall be equipped with anti-perch devices to reduce 

raven and raptor use, and limit predation opportunities on special status 

prey species.

4.3.1.2 Cumulative Effects

No other proposed projects were identified within the range of the 10(j) populations; 

however, it is anticipated that if any other projects were proposed/constructed, they

would be required to coordinate or consult with the USFWS on any potential project 

related impacts that could occur to this listed species. Furthermore, if other projects are 

constructed, their possible impacts to the black-footed ferret could include increased 

predation from raptors using the transmission towers, disturbance from maintenance 

activities, habitat loss, and impacts to prey base. These impacts could add cumulatively 

to impacts from Gateway West.

4.3.1.3 Critical Habitat

No critical habitat has been designated for the black-footed ferret.

4.3.2 Canada Lynx

4.3.2.1 Direct and Indirect Effects

Potential effects of the Project on Canada lynx include disturbance, loss or modification 

of habitat, and impacts to prey. Fragmentation of lynx habitats is not likely to occur as 

no LAUs would be crossed or impacted, and the projects effects to lynx linkage habitats 

is not expected to create long-term impacts that would fragment these habitats (see 

further discussion below).

If lynx are in the Action Area, construction and maintenance activities could cause lynx 

to avoid the area while these activities are taking place. Due to the Canada lynx’s large 

home range size (10 to 20 square miles) and high mobility, it would be relatively easy 

for individuals to avoid noisy project areas temporarily until activities ceased, without 

losing use of a large portion of their home range or adversely affecting the individual. 

Furthermore, it has been suggested that Canada lynx are generally tolerant of human 

presence (Staples 1995; Roe et al. 1999; Mowat et al. 2000; Ruediger et al. 2000), 

indicating that the amount of disturbance expected during construction or operation is 

unlikely to result in adverse impacts on this species. Also, studies have shown that 
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March 2013 92

moderately used roads do not appear to affect habitat use by lynx (McKelvey et al. 

2000; Ruediger et al. 2000).

Lynx linkage habitat consists of areas that provide landscape connectivity between 

blocks of primary lynx habitat. Linkage areas occur both within and between 

geographic areas where blocks of lynx habitat are separated by intervening areas of 

non-lynx habitat such as basins, valleys, or agricultural lands. These linkage habitats 

often consist of shrub-steppe habitats that contain low human and/or road densities and 

may provide important linkage habitat between the lynx’s primary forest habitat 

(Ruediger et al. 2000). Linkage habitat has been identified in Idaho, Montana, Utah, 

and Wyoming by an interagency/ intergovernmental panel (Forest Service 2007). The 

Project would cross multiple paths that have been designated as lynx linkage habitat 

(Forest Service 2007), all of which are located along Segment 4 (see Figure 3-4). This 

includes a linkage path that connects the southern portion of the Caribou-Targhee NF to 

the northeastern border of Utah; another linkage path connects the portion of the lynx 

core habitat that would be impacted by the Project to the northeastern border of Utah. 

Lynx would likely not utilize these linkage habitats during construction activities due to 

the presence of construction machinery and noise; resulting in a temporary adverse 

impact to the utility of these linkage habitats. Long-term impacts on the ability of these 

areas to serve as linkage habitats would be low due to the limited degree of habitat 

disturbance, lack of major active roads constructed through these habitats as a result of 

the Project, limited expected human presence in these areas during operation, the 

restoration and revegetation efforts proposed (see Appendix B of the EIS), as well as 

the Canada lynx tolerant of human presence and limited road use (Staples 1995; Roe et 

al. 1999; Mowat et al. 2000; Ruediger et al. 2000; McKelvey et al. 2000; Ruediger et al. 

2000). However, restoration in shrub-steppe habitats could take decades to restore 

conditions to preconstruction levels, and access roads could allow some illegal human 

access to these areas (even with the measures proposed to limit this illegal use); 

indicating that some effects to linkage habitats could continue beyond the construction 

phase, but to an unquantifiable degree. 

Snowshoe hares are the primary prey of lynx; therefore, any impacts from the Project 

on snowshoe hares could also impact lynx. Impacts to the snowshoe hare could 

include disturbance and loss or reduced function of habitat. However, there are no 

known occurrences of snowshoe hare in the Action Area (further indicating that the 

Action Area is not ideal habitat for the Canada lynx); therefore, adverse impacts to 

snowshoe hare are not expected. Lynx use other small mammals as prey where 

snowshoe hare are not available, such as red squirrel. Impacts to alternate lynx prey 

species would be similar to potential impacts on snowshoe hares. Although individual

small mammals could be impacted, a substantial overall decrease in small mammals in 

the Action Area that could impact lynx prey base is not expected due to the relatively 

small area impacted relative to a lynx’s home range, the high reproductive output of 

most small mammals, the abundance of small mammals in the area, and that the area 

impacts is not ideal lynx habitat (i.e., they are not expected to hunt primarily in this 

area).
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4.3.2.2 Cumulative Effects

No other proposed projects were identified within lynx LAUs or critical habitat; however, 

there is a proposed wind project (i.e., Mission Creek Wind Project) that would occupy 

about 2,051 acres of habitat within lynx linkage habitat. This would cumulatively add to 

the Project-related impacts to lynx linkage habitats. 

4.3.2.3 Critical Habitat

CHU 5 lies approximately 10 miles to the north of Segment 4 in Wyoming. This unit is

not within the Action Area, and the Project would have no effect on Canada lynx critical 

habitat.

4.3.3 Grizzly Bear

4.3.3.1 Direct and Indirect Effects

Direct and indirect impacts from the Project on grizzly bears could include disturbance, 

habitat loss and modification, and disruption of food sources. Noise and visual 

disturbance could cause grizzly bears to avoid the Action Area during construction and 

during maintenance activities in the operations phase. 

The Proposed Route would impact a total of about 2,561 acres of land within the range 

of the Yellowstone DPS; however, no lands would be impacted within the grizzly bear 

PCA or within areas identified by the USFWS as suitable grizzly bear habitats. The 

majority of impacts that would occur within the DPS boundary would occur adjacent to 

Highway 80, Highway 30, and the town of Kemmerer. Due to the wide habitat 

requirements of the grizzly bear, direct impacts to lands resulting from the Project’s 

construction would not have a measurable effect on habitat availability for this species. 

Furthermore, the Project has been re-routed to avoid known location of whitebark pine; 

therefore, no impacts to this important food source for grizzly bears are expected to 

occur.

4.3.3.2 Cumulative Effects

There are four proposed wind projects (see Table 3-17) that would occupy habitats 

within the range of the Yellowstone DPS of the grizzly bear. This would cumulatively 

add to the Project-related impacts to habits within the range of this species; however, no 

habitats identified as suitable or occupied by the grizzly bear would be impacted by 

Gateway West (thereby minimizing Gateway West’s contribution to cumulative effects).

4.3.3.3 Critical Habitat

No critical habitat has been designated for grizzly bears.

4.3.4 Preble’s Meadow Jumping Mouse

4.3.4.1 Direct and Indirect Effects

Direct and indirect impacts of the Project on the Preble’s meadow jumping mouse 

include disturbance, mortality, habitat loss or modification, fragmentation, and increased 

predation. Project impacts to the Preble’s meadow jumping mouse would be minimized 
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by conducting surveys in suitable habitats in Converse County, and micrositing the 

Project to avoid occupied areas. 

Noise and visual disturbance during construction and maintenance activities could make 

habitat temporarily unsuitable for Preble’s meadow jumping mice, causing them to 

suspend life activities such as foraging or mating, or to flee the area until disturbance 

ceased. This disruption of normal activities would last only as long as the disturbance, 

up to a couple weeks at most during construction. Individuals could also be killed by 

vehicles or equipment. This impact is expected to be minimal due to the speed limit that 

would be in effect on all lands regardless of ownership:

TRANS-6 Construction vehicles will follow a 25 miles per hour speed limit on 

unposted project roads.

The mobility of this animal would largely allow it to escape the danger of vehicle 

collisions. Increased predation, due to raptors using the transmission towers as perch 

sites for hunting and the removal of hiding cover, could also result in increased mortality 

to Preble’s meadow jumping mice. 

The Projects construction would impact approximately 245 acres of suitable Preble’s 

meadow jumping mouse habitat (i.e., wetlands and riparian areas as well as 328 feet 

beyond the 100-year floodplain in the eastern portion of the Project), while 

approximately 60 acres would be permanently disturbed (i.e., impacted by permanent 

facilities or by maintenance activities). All areas disturbed during construction (with the 

exception of areas used as permanent access roads, substation footprints, and pole 

structure bases) would be revegetated following construction in accordance with the 

Reclamation Plan (see Appendix B of the EIS). However, revegetation efforts are 

aimed primarily at reestablishing herbaceous or shrub cover, reestablishing original site 

configurations, and preventing erosion, but do not specifically address impacts to 

riparian zones, or the reestablishment of stream/wetland shade vegetation and/or LWD. 

Therefore, the Agencies have identified EPMs WET-1 (which would apply on federal 

land, plus all land in Wyoming and in Idaho along Segments 6, 8, and 9), and WET-2 

through WET-4 (which would apply on all lands, regardless of ownership), and TESWL14 (which the Agencies would require on federally managed lands) to reduce impacts to 

riparian habitats. 

WET-1 Impacts on wetland and riparian areas will be avoided unless physically 

or economically infeasible or where activities are permitted. Land 

management agencies’ plans (Resource Management Plans, 

Management Framework Plans, and Forest Plans) that have standards, 

guidelines, stipulations, or avoidance buffers will be adhered to. Where 

these do not exist, Inland Fish Strategy buffers will be followed.

WET-2 Wetland delineations will be performed prior to construction to support 

Clean Water Act (CWA) Section 404 permitting and to minimize Project 

impacts. The delineation will identify both wetland and non-wetland 

waters of the United States that would be affected by the Project.
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WET-3 Where impacts on wetlands are not avoidable, site-specific crossing 

plans and measures to mitigate impacts will be submitted to the 

appropriate regulatory agency, as well as the land managing agency. 

The Proponents will obtain all necessary permits prior to discharging 

dredged or fill material to waters of the U.S. and state.

WET-4 To meet U.S. Army Corps of Engineers (USACE) requirements for 

CWA 404 permitting, the Proponents will submit a mitigation plan that is

accepted by the USACE. The framework for this plan is included in the 

Final EIS.

TESWL-14 For the protection of aquatic and riparian/wetland dependent species, 

surface disturbing and disruptive activities will be avoided in the 

following areas: 1) identified 100-year floodplains; 2) areas within 500 

feet of perennial waters, springs, wells, and wetlands; and 3) areas 

within 100 feet of the inner gorge of ephemeral channels on federally 

managed lands. Where it is not possible to avoid wetland and riparian 

habitat, crossing-specific plans will be developed. These plans will: 1) 

demonstrate that vegetation removal is minimized; 2) show how 

sediment would be controlled during construction and operation within 

wetland and riparian areas; 3) attempt to intersect the wetland or 

riparian habitat at its edge; and 4) provide measures to restore habitat 

and ensure conservation of riparian microclimates. This plan will be 

submitted to the appropriate land management agency and approved 

prior to construction of any portion of the Project within sensitive 

riparian habitat.

Long-term habitat loss would primarily be associated with access roads, transmission 

pole structures, and substations; however, these would be located outside of wetland 

and riparian zones when feasible. This avoidance of wetland and riparian habitats 

would be conducted not only to minimize impact to these sensitive areas, but also 

because these areas are typically unsuitable for the long-term stability of project 

structures.

The transmission line would not serve as a barrier or hazard to the Preble’s meadow 

jumping mouse due to implementation of the above EPMs, plus additional EPMs that 

are listed in Table 2.7-1 of the EIS. However, any roads that are constructed within 

riparian habitats could result in a barrier to movement and could fragment habitat,

although these impacts would occur in areas outside of this species’ known range.

As discussed for the black-footed ferret, the presence of the transmission line could 

affect the predation rates for raptor and raven prey species (which would include the 

Preble’s meadow jumping mouse) by potentially consolidating raptor and raven 

populations along the line. The effect of increased raptor and raven predation rates 

would be most prominent where the Project is located in areas that do not already 

contain other tall structures, such as existing transmission lines or trees. However, the 

entire length of the portion of the Project located within the known range of the Preble’s 

meadow jumping mouse (see Figure 3-6) is located adjacent to (within 1 mile of) 

existing transmission lines that already serve as nesting and perching habitats for 
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raptors and ravens. To reduce the effects of the Project on raptor/raven predation 

pressures, EPM TESWL-1 would be applied on federally managed lands as well as

certain applicable state/private lands (see Table 2.7-1 in Chapter 2).

4.3.4.2 Cumulative Effects

There are three proposed transmission line projects (totaling 27 miles of crossed 

habitat) and one proposed wind farm (the windfarm proponents have not specified the

exact project footprint at this time) located within the analyzed range of the jumping 

mouse (see Table 3-17). This would cumulatively add to the Project-related impacts to 

habits within the range of this species.

4.3.4.3 Critical Habitat

The closest critical habitat to the Action Area is the North Fork Cache La Poudre River 

Unit in Larimer County, Wyoming, approximately 100 miles southeast of Segment 2 (75 

Federal Register 78430; Figure 3-6); therefore, the Project is not expected to impact 

critical habitat for the Preble’s meadow jumping mouse due to its distance from the 

Action Area.

4.4 Fish

4.4.1 Bull Trout Critical Habitat

As previously described, bull trout have not been documented to use the Bruneau River 

within the Jarbidge CHU. Fish associated with the Jarbidge critical habitat unit are 

found in the Jarbidge River watershed, over 25 miles to the south of the Action Area, so 

only critical habitat, not fish, may be affected by this crossing (64 Federal Register

17110). 

Segment 9 would span bull trout critical habitat along the Bruneau River, just south of 

C.J. Strike Reservoir. Vegetation at the crossing location was defined as “Wetland and 

Riparian” during Project-specific remote sensing, with adjacent areas defined as

“Disturbed Sagebrush.” Towers would be placed outside of the riparian area along the 

river in the disturbed sagebrush. The only riparian vegetation that may be removed are 

trees that are of sufficient height that they could interfere with the transmission lines; 

these would be removed individually. No construction work would occur and no towers 

or roads would be installed within critical habitat. Impacts to critical habitat from work 

nearby could include sedimentation from erosion and contamination from spills of 

hazardous materials. The risk of these impacts to bull trout critical habitat would be 

minimized by EPMs such as TESWL-14, which protects aquatic and riparian/wetland 

dependent species, plus additional EPMs such as the following, which would apply on 

all lands, regardless of ownership:

WQA-7 Approved sediment and erosion control BMPs will be installed and 

maintained until disturbed areas meet final stabilization criteria.

WQA-8 Temporary BMPs will be used to control erosion and sediment at 

staging areas (equipment storage yards, fly yards, lay down areas) and 

substations.
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WQA-10 Damaged temporary erosion and sediment control structures will be 

repaired in accordance with the Stormwater Pollution Prevention Plan 

(SWPPP).

WQA-11 Upon completion of construction, permanent erosion and sediment 

BMPs will be installed along the transmission line within the ROW, at 

substations, and at related facilities in accordance with the SWPPPs.

WQA-13 Construction industry standard practices and BMPs will be used for spill 

prevention and containment.

WQA-14 Construction spills will be promptly cleaned up and contaminated 

materials hauled to a disposal site that meets local jurisdictional 

requirements.

WQA-16 If an upland spill occurs during construction, berms will be constructed 

with available equipment to physically contain the spill. Absorbent 

materials will be applied to the spill area. Contaminated materials will 

be excavated and temporarily placed on and covered by plastic 

sheeting in a containment area a minimum of 100 feet away from any 

wetland or waterbody, until proper disposal is arranged. 

WQA-17 If a spill occurs which is beyond the capability of on-site equipment and 

personnel, an Emergency Response Contractor will be identified and 

available to further contain and clean up the spill.

WQA-18 For spills in standing water, floating booms, skimmer pumps, and 

holding tanks will be used as appropriate by the contractor to recover 

and contain released materials on the surface of the water.

WQA-28 Migration of construction-related sediment to all adjacent surface 

waterbodies will be prevented. 

The Proponents’ Spill Prevention, Containment, and Countermeasures (SPCC) Plan

would provide additional protection to aquatic and riparian habitats (see Appendix B of 

the EIS). These prevention and control measures, along with avoidance of critical 

habitat, would minimize the potential impacts on bull trout critical habitat PCEs. The 

limiting factors analysis for bull trout critical habitat is provided in Attachment B.

4.4.1.1 Cumulative Effects

No other proposed projects were identified within bull trout designated critical habitat; 

however, it is anticipated that if any other projects were proposed/constructed, they

would be required to coordinate or consult with the USFWS on any potential projectrelated impacts that could occur to this designated critical habitat. 

4.5 Invertebrates

4.5.1 Direct and Indirect Effects

Potential impacts to the four listed invertebrate species in the Action Area (i.e., Banbury 

Springs limpet, Bliss Rapids snail, Bruneau hot springsnail, and Snake River physa 
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snail) would include mortality and loss or modification of habitat. These impacts are 

unlikely, however, because no crossings by roads are proposed through the known 

distributions of these four species. In areas where the transmission line would cross 

these species’ recovery areas, these areas would be spanned, with no direct impacts 

expected occur to the snails or their habitat. Transmission towers would not be located 

in aquatic areas, per standard engineering practices. If snails are discovered outside of 

their currently known ranges and in the vicinity of Project activity, all requirements of the 

ESA would apply, including cessation of work, notification of USFWS, and possible reinitiation of consultation. 

The Project would not cross through the recovery area of the Banbury Springs limpet or 

the Bruneau hot springsnail. However, the transmission line would span the Bliss 

Rapids snail and Snake River physa snail recovery areas along three segments of the 

Snake River: at RM 541.5, RM 573.5, and RM 624.0. These crossings are located 

along areas that contain either agricultural or shrub-dominated habitats; therefore, only 

limited disturbance to vegetation would occur along these crossings (i.e., any individual 

trees that are tall enough to interfere with the transmission line would be removed). The 

potential removal of isolated trees along the mainstem of the Snake River at RM 541.5, 

RM 573.5, and RM 624.0 is not expected to result in substantial increases in stream 

temperatures due to the limited extent of existing vegetation present, but could result in 

some sedimentation. Vegetation clearing and weed control near water crossings would 

be conducted primarily via mechanical methods; however, some herbicides may be 

used. To prevent adverse impact to aquatic life resulting from potential herbicide use, 

the Proponents have proposed the following EPM, which would apply on federally 

managed land, and on all lands in Wyoming and along Segments 6, 8, and 9 in Idaho:

OM-20 Only herbicides approved by the land managing agency as safe to use 

in aquatic environments and reviewed by the Proponents for 

effectiveness will be used within 100 feet of sensitive aquatic resources.

EPMs WET-1 through WET-4 (see Section 4.3.4, above) would reduce impacts to 

riparian habitats due to loss of vegetation. If impacts are unavoidable, the Agencies 

have identified TESWL-14 to further reduce potential impact to wetland- and ripariandependent species. 

Disturbance adjacent to streams and springs occupied by any of these listed snails 

associated with construction of the ROW could result in sediment entering the water. 

Sedimentation would be controlled through the Proponents’ SPCC Plan, and the

Agencies have identified EPMs WQA-7, WQA-8, WQA-10, WQA-11, and WQA-28 (see

Section 4.4.1, above). This plan would also address spills of toxic materials that could 

enter streams and springs by requiring that fluids such as oil and fuel be stored at 

certain distances away from waterbodies. During ROW construction and maintenance, 

individual snails could also be crushed by personnel, vehicles, or equipment that enter

the water. These disturbances could also bury eggs or algal food supplies under 

sediment. However, because of the lack of crossings where the invertebrate species 

occur, this risk is unlikely. The BLM and USFWS recommend that if any changes to the 

siting of the transmission line or roads occur, the Proponents do not consider crossing 

cold-water springs or spring creeks near the Snake River or the Bruneau River when 
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developing their final engineering design. If changes to the locations of roads or the 

transmission line result in expected impacts to any of these four snails or their habitat, 

consultation with the USFWS would to be re-initiated. Long-term loss of habitat for any 

of these snails is not expected from the route currently being analyzed due to the limited 

scope of initial impact and the restoration efforts aimed at restoring the ROW following 

construction. 

If any road crossings are proposed and a culvert is needed, all culverts (both temporary 

and permanent) would be designed and installed to ensure the continued free flow of 

water, as well as to allow both the upstream and downstream movement of aquatic 

organisms. The following EPMs would apply on federally managed lands, and on all 

lands in Wyoming and in Idaho along Segments 6, 8, and 9:

FISH-1 On BLM-administered land, all culverts, whether temporary or 

permanent, must be designed to meet BLM Gold Book standards 

(Surface Operating Standards and Guidelines for Oil and Gas 

Exploration Development). On National Forest System lands, Forest 

Plan standards and guidelines shall apply.

WQA-24 On federal lands, consult with appropriate land management agency 

staff prior to siting and design for stream crossings (location, alignment, 

and approach for culvert, drive-through, and ford crossings). This may 

include a hydrologist, engineer and, for perennial and many intermittent 

streams, an aquatic biologist.

WQA-25 All culverts on National Forest System lands, both permanent and 

temporary, shall be designed and installed to meet desired conditions 

for riparian and aquatic species as identified in the applicable Forest 

Plan. Culverts should not be hydraulically controlled. Hydraulically 

controlled culverts create passage problems for aquatic organisms. 

Culvert slope should not exceed stream gradient and should be 

designed and implemented (typically by partial burial in the streambed) 

to maintain streambed material in the culvert.

WQA-26 Culvert sizing on National Forest Service lands should also comply with 

Guidance for Aquatic Species Passage Design, Forest Service 

Northern Region & Intermountain Region (Forest Service 2003).

The following measure would apply on non-federal lands:

WQA-27 On non-federal lands, culvert placement should comply with state 

BMPs.

As stated earlier, no road crossings or culverts are currently proposed through ESAlisted aquatic invertebrate habitats; however, if culverts were to be constructed and 

disturbance resulting from culvert construction is one acre or more, the Proponents 

would conduct construction and decommissioning of culverts under a Construction 

General Permit required for stormwater operations, which includes the development of 

BMPs to protect surface water from stormwater runoff. All culverts that are not 

necessary for operation of the Project would be removed in accordance with the 
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Proponents’ Traffic and Transportation Plan (see Appendix B of the EIS). In addition, 

culverts would be inspected regularly (permanent culverts inspected annually during 

operations) to make sure that they are not plugged and are functioning properly. The 

Proponents’ responsibility for inspecting culverts, as well as conducting all necessary 

repairs, would continue as long as the culverts are present within the watershed (this 

would continue for the life of the Project for permanent culverts). The BLM and Forest 

Service have specific requirements regarding culvert design and installation on lands 

they manage. The Proponents would consult with the Forest Service and BLM prior to 

construction, regarding design, layout, and decommissioning requirements for each 

temporary and permanent culvert that would located on federally managed lands. All 

culverts located on federally managed lands would be constructed in accordance with 

the applicable federal agency’s management plan standards. In addition, if any culverts 

are installed that could impact listed snails, the USFWS would be contacted to 

determine if further Section 7 consultation would be required. In all other areas where 

more restrictive regulations are not in place, the following specifications would be used:

• Culverts would be designed and installed under the guidance of a qualified 

engineer who, in collaboration with a hydrologist and aquatic biologist where 

required by the land management agency, would recommend placement 

locations; culvert gradient, height, and sizing; and proper construction methods. 

• Culvert design would consider bedload and debris size and volume. 

• The disturbance footprint for culvert installation is estimated to be 50 feet wide 

(along the waterbody) and 150 feet long (along the road) for 7,500 square feet or 

0.17 acre at each crossing. 

• Ground-disturbing activities would comply with Agency-approved BMPs. 

• Construction would occur during periods of low water or normal flow. 

• The use of equipment in streams would be minimized. 

• All culverts would be designed and installed to meet desired riparian conditions, 

as identified in applicable unit management plans. 

• Culvert slope would not exceed stream gradient. 

• Typically, culverts would be partially buried in the streambed to maintain 

streambed material in the culvert. Sandbags or other non-erosive material would 

be placed around the culverts to prevent scour or water flow around the culvert. 

Adjacent sediment control structures such as silt fences, check dams, rock 

armoring, or riprap may be necessary to prevent erosion or sedimentation. 

Stream banks and approaches may be stabilized with rock or other erosion 

control devices. 

• Culverts would be inspected and maintained annually for the life of the Project 

(estimated at 50 years or longer) for proper operation and to protect water 

quality.

Again, no road crossings or culverts are currently proposed through ESA-listed aquatic 

invertebrate habitats; however, these BMPs, EPMs, and construction design 

requirements would ensure that culverts would not impede the movement of, or 
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fragment aquatic habitats for, these listed aquatic invertebrates or other aquatic 

organisms, if road crossing layouts are changed in the future. 

As discussed for the Colorado and Platte River Systems, water may be withdrawn from 

the Snake River system (which includes the Bruneau River) during construction; 

however, the Proponents have committed to purchasing enough water to cover any 

needed water withdrawals from the Snake River system (see Appendix B of the EIS). 

As a result, water levels are not expected to decrease in the Snake or Bruneau Rivers 

due to this Project. The appropriate agencies would need to approve the final list of 

water sources purchased by the Proponents before the Notice to Proceed would be 

issued. No water withdrawals from springs along the Snake or Bruneau Rivers would 

be conducted by the Proponents or approved by the agencies nor would water be taken 

from existing wells that may currently draw their water from the Snake or Bruneau 

River’s thermal aquifers; as a result, no effects to the thermal aquifer along hot springs

in these rivers are expected.

4.5.2 Cumulative Effects

No reasonably foreseeable projects were identified near the areas where Banbury 

Springs limpet, Bliss Rapids snail, Bruneau hot springsnail, or Snake River physa snail 

are found; however, it can be assumed that ongoing and future agricultural usages will 

continue to develop in this area. Possible impacts to these snails and their habitat from 

these usages could include decreases in water quality if water is released into the 

Snake or Bruneau Rivers in or upstream of the distribution of any of these species; and 

decrease in water availability, if water is drawn or diverted from or upstream of the 

ranges of these snails. Agricultural uses (water diversions and irrigation, ground water 

pumping, and pesticide use) and aquaculture on non-Federal lands also impact water 

quality and availability essential for the recovery listed Snake River snails and the 

Bruneau hot springsnail. Furthermore, global climate change may alter precipitation 

rates in this area, resulting in more water demands on these water systems; this could 

have a detrimental effect on water levels in these systems. Climate change projections 

indicate that areas in central and southern Idaho may experience moderate to extreme 

drought over the next 50 years (Rieman and Isaak 2010, p. 5). Increasing temperatures 

(earlier spring snowmelt) and decreasing precipitation (declining snowpacks) may 

ultimately have impacts on flow volume in the Snake River. Should this result in 

increased human demand of river water (or decreasing availability of that resource), 

especially for agricultural use, reduced river flows and elevated water temperatures 

could further impair water quality (e.g., lowering dissolved oxygen concentrations). In 

addition, increased groundwater pumping in the Bruneau-Grand View geothermal 

aquifer that may occur due to increasing drought conditions would decrease the 

availability of hot spring habitat for the Bruneau hot springsnail. The multiple 

contingencies that could be attributable to climate change, forecasts for which are 

variable and uncertain, are difficult to predict with any degree of confidence; however, 

most scenarios would likely not be beneficial to listed Snake River snails or the Bruneau 

hot springsnail. These impacts could add cumulatively to impacts from Gateway West. 
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4.5.3 Critical Habitat

No critical habitat has been proposed or designated for Banbury Springs limpet, Bliss 

Rapids snail, Bruneau hot springsnail, or Snake River physa snail.

4.6 Plants

4.6.1 Blowout Penstemon

4.6.1.1 Direct and Indirect Effects

Impacts from the Project on blowout penstemon could include crushing or uprooting of 

individuals, loss or modification of habitat, alteration of fire regimes, and introduction or 

spread of invasive weeds. Blowout penstemon inhabits highly transitory, temporary, 

early-succession blowout habitats, the exact location of which can be somewhat difficult 

to predict. Although no known occurrences of blowout penstemon occur within the 

Action Area, USFWS has indicated that this plant is potentially found in all Wyoming 

counties crossed by the Action Area (USFWS 2012b). If occurrences of blowout 

penstemon are in the ROW, at a tower location, or where a road is planned for 

construction, plants, seedlings, seeds, or blowout habitat could be destroyed. In order 

to avoid this risk, the Proponents would implement TESPL-1 and TESPL-5 on federally 

managed lands and on all lands in Wyoming and in Idaho along Segments 6, 8, and 9

(see Section 5.8). Spread of invasive plants into blowout penstemon habitat would be 

minimized through EPMs that address weeds (see Table 2.7-1 of the EIS). This would 

also decrease the risk of fire associated with the Project. Risk of fire would be further 

reduced by installation and maintenance of gates at access points to the ROW (OM-6), 

which will reduce the amount of unauthorized access to the ROW by the public, which 

could cause fires from vehicles, campfires, and other means.

4.6.1.2 Cumulative Effects

Although blowout penstemon is not known to occur in the Action Area, all of the Action 

Area in Wyoming is considered to be potential habitat. In Wyoming, existing and 

reasonably foreseeable projects include transmission lines; roads; pipelines; coal, gas, 

wind, geothermal, and hydroelectric energy generation projects; oil, gas, and mineral 

extraction; commercial, industrial, and residential development; and land use 

restrictions. Possible impacts to this plant from these projects include crushing or 

uprooting of individuals, loss or modification of habitat, alteration of fire regimes, and 

introduction or spread of invasive weeds. These impacts could add cumulatively to 

impacts from Gateway West.

4.6.1.3 Critical Habitat

No critical habitat has been designated or proposed for blowout penstemon.

4.6.2 Ute Ladies’-Tresses

4.6.2.1 Direct and Indirect Effects

Possible impacts to Ute ladies’-tresses from Project construction and operations are 

trampling of plants and disturbance to seeds not showing a recognizable aboveground 

component. Ute ladies’-tresses is not known to occur in the Action Area, but USFWS 
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protocol surveys for this species will be carried out in certain areas containing suitable 

habitat, regardless of land ownership (TESPL-7; Section 5.9). Areas with suitable 

habitat where protocol surveys cannot be performed due to access or timing issues will 

be avoided. This will minimize the risk of physically destroying plants or seeds. 

Another potential impact is habitat removal and modification of hydrology resulting in a 

drying out of moist soils. Construction of roads could alter drainage patterns and cause 

wet areas to dry out, making them unsuitable for this plant; however, due to EPMs such 

as culvert installation and restoration of original land contours (REC-20, which would be 

applied on all lands), the risk of this is low. These EPMs include:

REC-20 Temporarily disturbed lands within the ROW will be re-contoured to 

blend with the surrounding landscape. Re-contouring will emphasize 

restoration of the existing drainage patterns and landform to preconstruction conditions, to the extent practicable. (Tower pads would 

not be re-contoured.)

REC-21 De-compaction: Areas within the ROW, laydown or staging yards, and 

other areas of extensive vehicle travel will typically contain compacted 

soils. These soils will be de-compacted on a case-by-case basis 

through negotiation with the landowner or land management agency. 

Because Ute ladies’-tresses occur most often in riparian areas and wetlands, measures 

that protect these habitat types would be implemented and would help minimize impacts 

to this orchid. Most riparian areas and wetlands would be spanned, and in those that 

are crossed by roads, measures, such as use of temporary matting for temporary 

access roads (in wetlands within the Bear River Plain), would be taken to minimize soil 

compaction and reduce vegetation damage. Measures that would help protect wetland 

and riparian habitat for Ute ladies’-tresses include:

WET-1 Impacts on wetland and riparian areas will be avoided unless physically 

or economically infeasible or where activities are permitted. Land 

management agencies’ plans (RMPs, MFPs, and Forest Plans) that 

have standards, guidelines, stipulations, or avoidance buffers will be 

adhered to. Where these do not exist, Inland Fish Strategy (INFISH) 

buffers will be followed,

WET-3 Where impacts on wetlands are not avoidable, site-specific crossing 

plans and measures to mitigate impacts will be submitted to the 

appropriate regulatory agency, as well as the land managing agency. 

The Proponents will obtain all necessary permits prior to discharging 

dredged or fill material to waters of the U.S. and state.

SOIL-4 Detrimental soil disturbance such as compaction, erosion, puddling, and 

displacement will be minimized through implementing measures 

identified in the SWPPP. Measures may include road ripping, frequent 

waterbars, cross-ditching (e.g., rolling dips) or other methods to reduce 

compaction while preventing gully formation. Ripping pattern should be 

altered to a crossing, diagonal, or undulating pattern of tine paths to 

avoid concentrated runoff patterns that can lead to gullies.
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WQA-1 The appropriate NPDES permits for construction activities that disturb 

one acre or more of land will be obtained from the Department of 

Environmental Quality and USEPA or their designees.

WQA-2 NPDES permit requirements will be met. This includes implementing 

and maintaining appropriate BMPs for minimizing impacts to surface 

water.

WQA-5 The Storm Water Pollution Prevention Plan (SWPPPs) will identify 

areas with critical erosion conditions that may require special 

construction activities or additional BMPs to minimize soil erosion.

WQA-6 Stormwater BMPs will be maintained on all disturbed lands during 

construction activities, as described in the SWPPP.

WQA-7 Approved sediment and erosion control BMPs will be installed and 

maintained until disturbed areas meet final stabilization criteria.

TESWL-14 For the protection of aquatic and riparian/wetland dependent species, 

surface disturbing and disruptive activities will be avoided in the 

following areas: 1) identified 100-year floodplains; 2) areas within 500 

feet of perennial waters, springs, wells, and wetlands; and 3) areas 

within 100 feet of the inner gorge of ephemeral channels on federally 

managed lands. Where it is not possible to avoid wetland and riparian 

habitat, crossing-specific plans will be developed. These plans will: 1) 

demonstrate that vegetation removal is minimized; 2) show how 

sediment would be controlled during construction and operation within 

wetland and riparian areas; 3) attempt to intersect the wetland or 

riparian habitat at its edge; and 4) provide measures to restore habitat 

and ensure conservation of riparian microclimates. This plan will be 

submitted to the appropriate land management agency and approved 

prior to construction of any portion of the Project within sensitive 

riparian habitat.

Additional measures identified in the SWPPP would be implemented to minimize 

detrimental soil disturbance such as compaction, erosion, puddling, and displacement. 

Disturbed areas would be revegetated and restored to preconstruction conditions as 

described in the Reclamation, Revegetation, and Weed Management Plan. 

Habitat loss through spread of invasive weeds would also be controlled through 

implementation of appropriate measures. Table 2.7-1 of the EIS lists all proposed 

EPMs for the proposed Project.

4.6.2.2 Cumulative Effects

Although Ute ladies’-tresses is not known to occur in the Action Area, potential habitat 

exists along Segments 1W through 5. Along these segments, existing and reasonably 

foreseeable projects include transmission lines; roads; pipelines; coal, gas, wind, 

geothermal, and hydroelectric energy generation projects; oil, gas, and mineral 

extraction; commercial, industrial, and residential development; and land use 
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restrictions and activities such as livestock grazing and pesticide use for weed control. 

Possible impacts to Ute ladies’-tresses from these projects include trampling and 

disturbance to seeds that could occur during construction or maintenance activities, and 

mortality of plants from livestock and weed control. These impacts could add 

cumulatively to impacts from Gateway West.

4.6.2.3 Critical Habitat

No critical habitat has been designated for Ute ladies’-tresses.

4.6.3 Slickspot Peppergrass

4.6.3.1 Direct and Indirect Effects

Direct and indirect impacts on slickspot peppergrass from the Project could include 

trampling of plants, destruction of seed beds, spread of invasive weeds, physical 

destruction of slickspots, changes in the fire regime, degradation of surrounding native 

sagebrush-steppe communities, fragmentation of populations, and loss of pollinators. 

Spread of invasive weeds as a result of Project construction, operation, and 

maintenance may not only result in direct competition between non-native species and 

slickspot peppergrass and alteration of this species habitat, but may result in increased 

fire risk, which may also affect slickspot peppergrass individuals and/or occupied and 

potential habitat. Soil compaction from construction and maintenance vehicles, where 

slickspots are not avoidable, may also directly affect individuals of and habitat for this 

species. Although minor in scale, impacts associated with road construction and 

improvement and structure placement could directly and indirectly impact individuals 

and habitat for slickspot peppergrass habitat. Loss or degradation of native shrub cover 

and/or biological soil crusts in occupied or potential slickspot peppergrass habitat could 

also indirectly affect this species. Attachment A provides further assessment of the 

potential direct and indirect effects to slickspot peppergrass from Project construction 

and operations.

Preconstruction surveys for slickspot peppergrass and slickspots within potential habitat 

and slickspot peppergrass habitat prior to construction will be carried out (TESPL-3; 

Section 5.10). If no slickspots are found during surveys, the area would be considered 

unoccupied and construction would proceed, and if slickspots are found, the area would 

be considered occupied. For a slickspot or other habitat that is considered occupied to 

be deemed unoccupied and for ground disturbance to be permitted to proceed, 3 years 

of surveys must be carried out during years with at least 60 percent of average spring 

precipitation. Plants and slickspots found during surveys would be marked and avoided 

by 50 feet on all lands, regardless of ownership (TESPL-4; Section 5.10). No overland 

travel or vegetation clearing would be conducted within slickspots. Also, no topsoil 

would be stored in slickspots. Alteration of habitat by spread of invasive annual plants 

would be minimized through implementation of measures designed to prevent the 

spread of weeds during habitat rehabilitation (see Table 2.7-1 of the EIS); minimizing 

the proliferation of weeds in slickspot peppergrass habitat would also prevent long-term 

changes to the fire regime. The creation of roads into slickspot peppergrass habitat 

could result in an increased chance of fires starting due to increased human presence 

(both Project-related and unauthorized) in the ROW. This would be minimized by 
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implementing measures aimed at preventing accidental fires, and by preventing 

unauthorized access to the Action Area (see Table 2.7-1 of the EIS). Removing native 

sagebrush-steppe vegetation surrounding occupied slickspots would fragment slickspot 

peppergrass populations, and also impact insect pollinators upon which this plant 

depends. Insect pollinators of slickspot peppergrass require sufficient quantity and 

diversity of native plants that flower throughout the season and provide cover and 

nesting substrate. All Project activities will adhere to the applicable 2006 Conservation 

Agreement (BLM and USFWS 2006) and updated 2009 measures. 

4.6.3.2 Cumulative Effects

Multiple wind-farms have been proposed within the assessed range of the slickspot 

peppergrass, with a combined estimated footprint of 3,620 acres within the assessed 

range of this species (see Table 3-17). Possible impacts to slickspot peppergrass from 

these reasonably foreseeable actions include trampling, seedbed destruction, spread of 

invasive weeds, physical destruction of slickspots, changes to the fire regime, 

degradation of surrounding native sagebrush-steppe communities, fragmentation of 

populations, and loss of insect pollinators. These impacts could add cumulatively to 

impacts from the Project.

4.6.3.3 Critical Habitat

Two units, units 2 and 3, of proposed critical habitat would be within the Action Area for 

the Project, near Segment 8. Approximately 4,378.8 acres of proposed critical habitat 

occur within the Action Area, the majority of which (approximately 73 percent) is within 

Unit 2. Approximately 188.6 acres3 of proposed critical habitat, 180.5 acres in Unit 2 

and 8.1 acres in Unit 3, occur within the Project footprint. Additionally, construction and 

operation could potentially impact PCEs 2, 3, and 4 within these units of critical habitat. 

Project construction, operation and maintenance could increase the spread or 

proliferation of which could impact PCEs 1 (slickspots with sparse vegetation), 2 (intact 

native vegetation assemblages), 3 (a diversity of native plants), and 4 (sufficient 

pollinators). Clearing of the ROW could impact PCE 2, PCE 3 (undisturbed suitable 

habitat for native pollinators), and PCE 4 (sufficient pollinator populations) by removing 

native vegetation, fragmenting habitat, and destroying insect pollinator nesting sites. 

Additionally, soil compaction from overland travel of construction and maintenance 

vehicles, where slickspots are not avoidable, may affect slickspot peppergrass and PCE 

1 (3-layer soil horizonation sequence, slickspots with sparse vegetation, and low 

invasive plant cover) of proposed critical habitat.

The risk of these impacts would be minimized by restoration of areas disturbed during 

construction, de-compaction of areas with extensive vehicle travel, weed control, and 

preconstruction surveys and subsequent micrositing of Project components to avoid 

slickspots, where possible (see Table 2.7-1 of the EIS and Section 5.10). 

 

3 Acres are for entire Project footprint including entire ROW. Only a portion of the ROW would be disturbed for 

Project construction and operation and maintenance.
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5 CONSERVATION MEASURES TO AVOID OR MINIMIZE

ADVERSE IMPACTS

The following procedures would be implemented by the Proponents and their 

contractors to eliminate or substantially reduce the likelihood of potential adverse effects 

of the proposed project on threatened and endangered wildlife and plant species and

their habitats. Agency-proposed and Proponent-proposed measures that specifically 

address the listed species addressed in this BA are presented below. Many additional

measures that would protect these species, but were not written specifically for them

(e.g., those addressing vegetation restoration, construction site clean-up, erosion, fire, 

invasive weeds, dust, water quality, herbicides, training project personnel regarding 

protection of biological resources, and survey requirements), are presented in Table 

2.7-1 of the EIS.

5.1 Platte and Colorado River Species

The following EPM would be required (based on the USFWS tiered Biological Opinion 

on the Colorado River water withdrawals) if the Project results in depletions greater than 

100 acre-feet per year from the Colorado River:

TESWL-12 Colorado River T&E Fishes – A payment of a one-time fee, based on a 

fee schedule provided by the USFWS, will be made based on the 

amount of water used during construction of any segments that cross 

the Colorado River system.

Other mitigation and environmental protection requirements that would protect Platte 

and Colorado River listed species are listed in the respective programs for these two 

basins (Bureau of Reclamation and USFWS 2006; USFWS 2006a; NPS 2006; USDI 

2005).

5.2 Black-footed Ferret

The Project proposal (see Appendix B of the EIS) includes a preconstruction survey for 

black-footed ferrets in white-tailed colonies. However, to ensure complete coverage of 

suitable habitat (i.e., the potential for black-footed ferret presence in black-tailed prairiedog colonies as well as white-tailed colonies), TESWL-3 would be implemented on all 

land ownerships. 

TESWL-3 Black-Footed Ferret – Pre-construction surveys will be conducted for the 

black-tailed prairie dog (in addition to those already proposed for the 

white-tailed prairie dog) in Segment 1W.

5.3 Canada Lynx

There are no specific EPMs for the Canada lynx; however, as stated above, general 

measures would be applied (e.g., those addressing vegetation restoration, construction 

site clean-up, erosion, fire, invasive weeds, dust, water quality, herbicides, training

project personnel regarding protection of biological resources, and survey 

requirements).
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5.4 Grizzly Bear

There are no specific EPMs for the grizzly bears; however, as stated above, general 

measures would be applied (e.g., those addressing vegetation restoration, construction 

site clean-up, erosion, fire, invasive weeds, dust, water quality, herbicides, training

project personnel regarding protection of biological resources, and survey 

requirements).

5.5 Preble’s Meadow Jumping Mouse

The Proponents have committed, in their POD, to conduct preconstruction surveys for

threatened and endangered species in suitable habitats (see Appendix B of the EIS). 

As stated above, there are no specific EPMs for the Preble’s meadow jumping mouse; 

however, general measures would be applied (e.g., those addressing vegetation 

restoration, construction site clean-up, erosion, fire, invasive weeds, dust, water quality, 

herbicides, training project personnel regarding protection of biological resources, and 

survey requirements).

5.6 Bull Trout

There are no specific EPMs for the bull trout; however, as stated above, general 

measures would be applied (e.g., those addressing vegetation restoration, construction 

site clean-up, erosion, fire, invasive weeds, dust, water quality, herbicides, training

project personnel regarding protection of biological resources, and survey 

requirements).

5.7 Invertebrates

There are no specific EPMs for the listed invertebrates; however, as stated above, 

general measures would be applied (e.g., those addressing vegetation restoration, 

construction site clean-up, erosion, fire, invasive weeds, dust, water quality, herbicides, 

training project personnel regarding protection of biological resources, and survey 

requirements).

5.8 Blowout Penstemon

To avoid impacting blowout penstemon, the Proponents have proposed the following 

species-specific EPMs, which would apply on federally managed lands, and all lands in 

Wyoming and along Segments 6, 8, and 9 in Idaho:

TESPL-1 Blowout Penstemon – Surface disturbance will be allowed in suitable 

habitat for blowout penstemon where species-specific surveys have 

determined that no populations are present. The species-specific 

surveys will be conducted the year prior to construction, and the 

proposed disturbance areas will be redesigned to avoid direct impact to 

populations.

TESPL-5 Sand dune plant communities should be avoided, where feasible.
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5.9 Ute Ladies’-Tresses

To comply with USFWS requirements regarding this orchid, the following EPM would 

apply on all lands, regardless of ownership:

TESPL-3 Qualified botanists shall conduct preconstruction surveys during a 

season when target species are readily identifiable for special status or 

globally rare species. Where feasible, micrositing of project facilities 

shall avoid direct impacts to identified populations. Survey reports 

documenting the surveys, their results, and recommendations must be 

provided to land management agency for approval prior to construction. 

Agency botanists may evaluate individual sites based on site-specific 

conditions. Documentation of the evaluation of avoidance of impacts to 

sensitive and globally rare plants must be provided to the Agencies 

prior to construction.

TESPL-7 Ute ladies’-tresses – Qualified botanists shall conduct preconstruction 

surveys during a season when target species are readily identifiable for 

special status or globally rare species. Where feasible, micrositing of 

project facilities shall avoid direct impacts to identified populations. 

Survey reports documenting the surveys, their results, and 

recommendations must be provided to land management agency for 

approval prior to construction. Agency botanists may evaluate 

individual sites based on site-specific conditions. Documentation of the 

evaluation of avoidance of impacts to sensitive and globally rare plants 

must be provided to the Agencies prior to construction.

5.10 Slickspot Peppergrass

To comply with BLM Manual 6840 direction and the U.S. Department of the Interior

Conservation Agreement (USDI 2006) concerning slickspot peppergrass, the following 

measures would be employed where there is the potential to encounter slickspot 

peppergrass. 

The following EPM would apply on all lands, regardless of ownership:

TESPL-3 Qualified botanists shall conduct preconstruction surveys during a 

season when target species are readily identifiable for special status or 

globally rare species. Where feasible, micrositing of project facilities 

shall avoid direct impacts to identified populations. Survey reports 

documenting the surveys, their results, and recommendations must be 

provided to land management agency for approval prior to construction. 

Agency botanists may evaluate individual sites based on site-specific 

conditions. Documentation of the evaluation of avoidance of impacts to 

sensitive and globally rare plants must be provided to the Agencies 

prior to construction.

TESPL-4 Slickspot Peppergrass – Environmental monitors will survey for and 

mark slickspots and aboveground populations of slickspot peppergrass 
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within 50 feet of the construction area prior to ground disturbance 

(including roads) in potential or occupied slickspot peppergrass habitat. 

No construction shall occur within 50 feet of any slickspot peppergrass 

plants or slickspots found by the environmental monitor. Also, 

construction shall not occur within 50 feet of previously known occupied 

slickspot peppergrass areas, based on Idaho Conservation Data Center

data, even if aboveground plants are not observed by the environmental 

monitor. Within proposed critical habitat, impacts to Primary Constituent 

Elements, such as native sagebrush/forb vegetation, will be avoided to 

the extent practicable. Seeding during reclamation in areas of suitable 

habitat will use methods that minimize soil disturbance such as no-till 

drills or rangeland drills with depth bands. Reclamation will use certified 

weed-free native seed. Excess soils will not be stored or spread on 

slickspots.

The terms “potential and occupied” habitat in EPM TESPL-4 do not specifically refer to 

the BLM categories because the EPM was designed for all lands (see Table 2.7-1 in the 

Final EIS). However, it is assumed that all areas of potential and/or occupied habitat, 

including slickspot peppergrass habitat as defined by the BLM (see Attachment A), 

would be surveyed for slickspot peppergrass on BLM-managed lands. All surveys for 

slickspot peppergrass would be conducted in accordance with current BLM survey 

protocols for this species (i.e., protocols used by the BLM at the time of the survey).

6 INTERRELATED AND INTERDEPENDENT ACTIONS

Effects of the action under consultation are analyzed together with the effects of other 

activities that are interrelated to, or interdependent with, that action (50 CFR 402.01). 

Interrelated actions are those that are part of a larger action (i.e., the action under 

consultation) and depend on the larger action for their justification. Interdependent 

actions are those that have no significant independent utility apart from the action under 

consideration. Interrelated or interdependent actions can include actions under the 

jurisdiction of other federal agencies, state agencies, or private parties.

An interrelated activity is an activity that is part of the proposed action and depends on 

the proposed action for its justification or is associated with the proposed action. An 

interdependent activity is an activity that has no independent utility apart from the action 

under consultation or because of the proposed action. There are no projects identified 

as either interrelated or interdependent actions associated with the Agency Preferred 

Alternative for Gateway West. 

7 IRREVERSIBLE OR IRRETRIEVABLE COMMITMENT

OF RESOURCES

Section 7(d) of the ESA prohibits federal agencies and permit applicants from making 

any "irreversible or irretrievable commitment of resources" that has the effect of 

foreclosing the formulation or implementation of any reasonable and prudent alternative 

measures which would not violate section 7(a)(2) of the Act, during consultation under 
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section 7(a)(2). Section 7(a)(2) prohibits federal actions that jeopardize the continued 

existence of listed species or that destroy or adversely modify their critical habitat. After 

initiation or any reinitiation of consultation required under section 7(a)(2) of the Act, the 

federal agency and any applicant shall make no irreversible or irretrievable commitment 

of resources with respect to the agency action during the consultation process and 

continues until the requirements of section 7(a)(2) are satisfied. This provision does not 

apply to the conference requirement for proposed species or proposed critical habitat 

under section 7(a)(4) of the ESA.

Irreversible commitments of resources are those that would be committed to the Project 

throughout the life of the Project. Irretrievable commitments of resources are uses of 

resources that are neither renewable nor recoverable for use during or beyond the life of 

the Project. Irreversible and irretrievable impacts to ESA-listed plants and wildlife from 

the Project could include mortality to individuals, for example birds colliding with Project 

structures or plants that are trampled; removal of habitat, especially trees and slickspot 

microsites; and impacts to aquatic habitats. The potential for these impacts are 

analyzed in detail in Sections 3 and 4 of this BA. Section 5 discusses various 

conservation measures to avoid and minimize impacts.

8 EFFECTS OF THE PROJECT ON THE EXPECTED 

STATUS OF SPECIES IN THE FUTURE

Provided that the measures described in Section 6 are implemented, the proposed 

action is not expected to alter the current status of, or result in any decreased survival 

of, any of the species discussed in this document during the Project or after Project 

completion.

9 DETERMINATION OF EFFECTS SUMMARY FOR 

LISTED SPECIES

Determination of effects for listed species are discussed by species in the following 

subsections and summarized in Table 9-1 at the end of this section.

9.1 Colorado River Species

The Colorado pikeminnow, bonytail chub, humpback chub, and razorback sucker, and 

designated critical habitat for each of these species, occur downstream of the Action Area

within the Colorado River basin, and thus have the potential to be impacted by water 

withdrawals from the Colorado River basin. The Proponents have committed (in their POD) 

to purchasing enough water (from existing water withdrawals for which consultation has 

already occurred) to cover any water needs from the Colorado River system. However, the 

Proponents have not yet identified the sources or exact amount of water they plan to 

purchase, nor have they secured these water withdrawals at this time. As a result, it is 

uncertain if the Proponents would be able to acquire enough water, in which consultation 

with the USFWS has already occurred, to cover the Project’s water needs. Therefore, until 

these water needs have been fully identified and enough water has been acquired, the 

threat determination for this Project would be may affect, likely to adversely affect for the 
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Colorado pikeminnow, razorback sucker, humpback chub, and bonytail chub and a may 

affect, not likely to adversely affect determination for their critical habitat. The appropriate 

agencies would need to approve the final list of water sources the Proponents would 

purchase before the Notice to Proceed would be issued.

9.2 Platte River Species

The interior least tern, piping plover, whooping crane, pallid sturgeon, and western 

prairie fringed orchid, and designated critical habitat for the whooping crane, occur 

downstream of the Action Area within the Platte River basin, and thus have the potential 

to be impacted by water withdrawals from the Platte River basin. The Proponents have 

committed (in their POD) to purchasing enough water (from existing water withdrawals 

for which consultation has already occurred) to cover any water needs from the Platte 

River system. However, the Proponents have not yet identified the sources or exact 

amount of water they plan to purchase, nor have they secured these water withdrawals 

at this time. As a result, it is uncertain if the Proponents would be able to acquire 

enough water, in which consultation with the USFWS has already occurred, to cover the 

Project’s water needs. Therefore, until these water needs have been fully identified and 

enough water has been acquired, the threat determination for this Project would be may 

affect, likely to adversely affect for the pallid sturgeon, interior least tern, whooping 

crane, piping plover, and western prairie fringed orchid and a may affect, not likely to 

adversely affect determination for critical habitat for the whooping crane. The 

appropriate agencies would need to approve the final list of water sources the 

Proponents would purchase before the Notice to Proceed would be issued.

9.3 Black-Footed Ferret

The Project could have direct and indirect effects on individual black-footed ferrets within the 

10(j) population (along Segment 1 and 2). Project impacts to black-footed ferrets would be 

minimized by micrositing the Project to avoid active burrows identified prior to construction. 

As a result, the Project may affect, but is not likely to adversely affect, the reintroduced 10(j) 

population (i.e., the nonessential experimental population of black-footed ferrets).

9.4 Canada Lynx

The Project would pass within a few miles of two LAUs but would not cross or impact 

LAUs. The Project would cross lynx linkage areas (Figure 3-4). The Project is not 

expected to have a substantial long-term impact to linkage areas, nor is it expected to 

substantially impact the lynx’s prey base or result in long-term impedance to movement. 

Therefore, the Project’s construction and operations may affect, but are not likely to 

adversely affect, the Canada lynx. The Project would not cross designated critical 

habitat for Canada lynx or impact any PCEs; therefore, the Project would have no effect

on lynx critical habitat.

9.5 Grizzly Bear

The Project would cross through the southern extent of the grizzly bear’s Yellowstone 

DPS adjacent to Highway 80, Highway 30, and the town of Kemmerer (i.e., in an area 

highly disturbed by human developments and activities). The Project would not cross 
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through or impact the PCA or areas identified by the USFWS as suitable grizzly bear 

habitats. As a result, the Project’s construction and operations may affect, but are not 

likely to adversely affect, the grizzly bear.

9.6 Preble’s Meadow Jumping Mouse

The Project could have direct and indirect effects Preble’s meadow jumping mouse. 

Project impacts to this species would be minimized by conducting preconstruction 

surveys in suitable habitats in Converse County, and micrositing the Project to avoid 

occupied areas. As a result, the Project may affect, but is not likely to adversely affect

the Preble’s meadow jumping mouse.

9.7 Bull Trout

Because there is no distribution of bull trout within the Action Area, the Project is 

expected to have no effect on bull trout.

Construction would not take place within critical habitat; however, the transmission line 

would span critical habitat. No road crossings within critical habitat are proposed. 

Removal of riparian vegetation would be limited to any trees of sufficient height to 

interfere with transmission lines. EPMs and the Proponents’ SPCC Plan would be in 

place to prevent erosion, sedimentation, and hazardous material spills. However, the 

critical habitat is within the Action Area for the Project, and there is a potential for 

impacts to the stream (due to removal of individual trees); therefore, the Project may 

affect, but is not likely to adversely affect bull trout critical habitat.

9.8 Invertebrates

No road crossings are proposed within habitats that support any of the four listed 

aquatic snails analyzed in this document. The transmission line would span habitat for 

these species in areas that currently contain agricultural or shrubland vegetation; 

therefore, vegetation removal and maintenance would be minimal. In addition, the 

Proponents have committed to purchasing enough water to cover any needed water 

withdrawals from the Snake River system; therefore, effects associated with decreased 

water levels in the Snake River due to this Project are not anticipated to occur. No 

water withdraws from springs along the Snake or Bruneau River would be conducted by 

the Proponents or approved by the agencies nor would water be taken from any existing 

wells that may currently draw their water from the Snake or Bruneau River’s thermal 

aquifers; as a result, no effects to the thermal aquifer along the Bruneau River hot

springs are expected. EPMs would be applied to limit potential impacts to riparian- and 

wetland-dependent species. Based on impacts related to the limited ROW maintenance 

and the implementation of EPMs, the Project may affect, but is not likely to adversely 

affect, the Banbury Springs limpet, Bliss Rapids snail, Bruneau hot springsnail, or 

Snake River physa snail.

9.9 Blowout Penstemon

The known distribution of blowout penstemon does not overlap with the Action Area, and 

detailed vegetation mapping within the Action Area shows no suitable sand dune habitat for 

this plant species. Therefore, the Project would have no effect on blowout penstemon.
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9.10 Ute Ladies’-Tresses

This species is difficult to survey for because it does not flower every year and is 

inconspicuous when not in flower. In addition, populations may consist of a small 

number of plants that can easily be missed by surveyors. A one-time survey could miss 

populations if it was conducted before or after blooming occurs, even if it is carried out

during the proper survey window. If populations are missed during the surveys, Ute 

ladies’-tresses plants and/or populations could be destroyed or damaged during 

construction. No known Ute ladies’-tresses populations occur within the Action Area;

however, known occurrences should not be considered exhaustive. Therefore, where 

the Proponents have permission to access areas of suitable Ute ladies’-tresses habitat, 

three years of surveys have been carried out, following USFWS protocol for this species 

(USFWS 1992b). The plant was not found in surveyed areas following 3 years of 

protocol surveys. Where the Proponents did not have permission to survey, and where 

suitable habitat is present, the Project alignment will be modified and routed to avoid 

these areas. However, indirect effects could still occur to this plant due to alterations in 

hydrology and the spread of weeds. Therefore, this Project may affect, but is not likely 

to adversely affect, Ute ladies’-tresses.

9.11 Slickspot Peppergrass

The Proponent-proposed EPMs are insufficient to protect slickspot peppergrass 

because this species is an annual or biennial plant, and its aboveground populations 

may fluctuate greatly from year to year, depending on precipitation or other 

environmental factors. The aboveground plants represent only a small portion of the 

population, with the largest components consisting of the soil-stored seed bank. Only a 

small portion of the seeds germinate in a single year; therefore, the seed bank typically 

covers a larger area than what is occupied by aboveground plants in any given year. A 

single preconstruction survey could miss slickspot peppergrass populations, and 

slickspots that do not currently exhibit aboveground plants could still contain this 

species. Three years of surveys are required in order to say that habitat is unoccupied 

by slickspot peppergrass. It is unlikely that these survey requirements could be met in 

all areas of potential habitat and slickspot peppergrass habitat prior to construction. In 

addition, the Project would not be able to avoid impacting all slickspots or occupied 

slickspot peppergrass habitat, or the associated native shrub-steppe ecosystem 

necessary to support sufficient pollinators for this plant. Project construction, operation, 

and maintenance could increase the potential for further spread and proliferation of nonnative plants and increased risk of wildland fire, which may affect slickspot peppergrass 

and slickspot peppergrass habitat. Additionally, soil compaction, soil disturbance, loss 

of native vegetation, and disturbance or loss of biological crusts due to Project activities 

may occur and may affect slickspot peppergrass and slickspot peppergrass habitat. 

Therefore, the BLM determined that the Project may affect, and is likely to adversely 

affect, slickspot peppergrass.

Proposed critical habitat would be crossed by the ROW of Segment 8. Impacts of the 

Project on this proposed critical habitat could include the spread of invasive plants, 

removal of native vegetation near slickspots, destruction or alteration of slickspots, and 

impacts to undisturbed suitable habitat for native pollinators. These impacts are 
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expected to be minimized by conducting preconstruction surveys for slickspots and 

avoiding observed slickspots by 50 feet, minimizing removal of native vegetation within 

820 feet of EOs (which includes proposed critical habitat), and restoring any native 

vegetation removed. The BLM determined that Project may affect, and is likely to 

adversely affect, proposed critical habitat for slickspot peppergrass.

Table 9-1. Summary of Effects Determination of Federally Threatened and Endangered 

Wildlife and Plant Species Occurring in Idaho and Wyoming

Species Status Effect Determination

Colorado River Species

Colorado pikeminnow (Ptychocheilus lucius) Endangered

May affect, likely to adversely affect Razorback sucker (Xyrauchen texanus) Endangered

Bonytail chub (Gila elegans) Endangered

Humpback chub (Gila cypha) Endangered

Critical habitat for the four endangered 

Colorado River fish Designated May affect, not likely to adversely affect

Platte River Species

Interior least tern (Sterna antillarum 

athalassos) Endangered

May affect, likely to adversely affect

Piping plover (Charadrius melodus) Threatened

Whooping crane (Grus americana) Endangered

Pallid sturgeon (Scaphirhynchus albus) Endangered

Western prairie fringed orchid

(Platanthera praeclara) Threatened

Whooping crane critical habitat Designated May affect, not likely to adversely affect

Mammals

Black-footed ferret (Mustela nigripes)

Endangered No effect

Nonessential, 

experimental 

population

May affect, not likely to adversely affect

Canada lynx (Lynx canadensis) Threatened May affect, not likely to adversely affect

Grizzly bear (Ursus arctos) Threatened May affect, not likely to adversely affect

Preble’s meadow jumping mouse

(Zapus hudsonius preblei) Threatened May affect, not likely to adversely affect

Fish

Bull trout critical habitat Designated May affect, not likely to adversely affect

Invertebrates

Banbury Springs limpet (Lanx sp.) Endangered May affect, not likely to adversely affect

Bliss Rapids snail (Taylorconcha 

serpenticola) Threatened May affect, not likely to adversely affect

Bruneau hot springsnail (Pyrgulopsis 

bruneauensis) Endangered May affect, not likely to adversely affect

Snake River physa snail (Physa natricina) Endangered May affect, not likely to adversely affect

Plants

Blowout penstemon (Penstemon haydenii) Endangered No effect

Ute ladies’-tresses (Spiranthes diluvialis) Threatened May affect, not likely to adversely affect

Slickspot peppergrass (Lepidium papilliferum) Proposed 

Endangered May affect, likely to adversely affect

Slickspot peppergrass critical habitat Proposed May affect, likely to adversely affect
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ATTACHMENT A

DEFINITIONS OF HABITAT CATEGORIES AND EFFECT ASSESSMENT 

FOR SLICKSPOT PEPPERGRASS 
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Definitions of Habitat Categories for Slickspot Peppergrass as described within 

Bureau of Land Management Biological Assessment (BLM 2009, p. B-2 and BLM 

2012, pp. 7-8)

Potential Habitat –

Areas within the known range of slickspot peppergrass that have certain general soil 

and elevation characteristics that indicate the potential for the area to support 

slickspot peppergrass, although the presence of slickspots or the plant is unknown. 

These areas meet the following criteria:

−Natric and natric-like soils forming “slickspots,” and associated soil series, or 

phases thereof, which support Loamy 7- to 10-inch and 10- to 13-inch Wyoming 

big sagebrush Ecological Sites (Major Land Resource Areas 11—Snake River 

Plains, and 25—Owyhee High Plateau) and have an aridic bordering on xeric soil 

moisture regime; and

− 2,200 to 5,400 feet elevation.

Occupied Habitat –

In the BLM’s 2012 Assessment, the term “occupied habitat” refers to areas where 

slickspot peppergrass has been documented or identified as an element occurrence 

(EO) and includes the area generally within 0.5 mile of that occurrence that is 

important to maintain or improve habitat integrity and pollinator populations 

necessary for species conservation. For analysis purposes in this BA, a generalized 

area delineated by a 0.5 mile radius circle was drawn around each EO (this circle 

may include areas of non-habitat). This area identified as occupied habitat may or 

may not include additional slickspots or slickspot peppergrass plants beyond the EO. 

Further refinement of occupied habitat may be accomplished through field surveys 

considering existing resource conditions as well as specific habitat quality and 

integrity. 

Slickspot Peppergrass Habitat –

Potential habitat areas with Wyoming big sagebrush ecological sites that through 

Stage 1 surveys have documented slickspot microsites (natric and natric-like soil 

types) within 2,200 feet and 5,400 feet elevation in Southwest Idaho. Slickspot

peppergrass habitat includes areas with slickspots of unknown occupancy and, in 

some cases, may be dominated by non-native vegetation such as annual grasses or 

crested wheatgrass (Agropyron cristatum). In addition, to maintain ecological

continuity, if there is less than 0.5 mile between areas defined as slickspot 

peppergrass habitat, then the entire area is considered slickspot peppergrass 

habitat. Surveyed potential habitat not meeting these criteria will no longer be 

considered habitat for slickspot peppergrass.
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Slickspot Peppergrass Assessment

EFFECTS DETERMINATION CHECKLIST FOR SLICKSPOT PEPPERGRASS 

SLICKSPOT PEPPERGRASS PHYSIOGRAPHIC REGION NAME__Snake River Plains 

NAME OF PROJECT BEING EVALUATED:___Gateway West Transmission Project 

/or suitable habitat.

PROJECT TYPE Energy Development and Transmission 

PROJECT STATUS Proposed Action 

NARRATIVE SUMMARY OF SLICKSPOT PEPPERGRASS OBSERVATIONS WITHIN 

ACTION AREA (Element Occurrence #, Element Occurrence Ranking, Survey Year, 

Survey Intensity, Number of Slickspot Peppergrass Plants Observed, Precipitation within 

Survey Year, etc.) 

No Project specific surveys for slickspot peppergrass have been conducted within the Action 

Area.

Element Occurrence Number(s): 

EOs that are within the Action Area and intersected by the Project footprint: 

EO Number EO Rank

Within Action 

Area

Intersected by 

Project 

Footprint

15 D Yes No

18 C Yes No

24 C Yes Yes

25 C Yes No

30 B Yes Yes

31 C Yes Yes

42 F Yes Yes

51 BD Yes No

54 F Yes No

72 C Yes No

104 C Yes Yes

Occupied habitat (i.e., the 0.5-mile buffer around the EO) of two additional EOs, EO 62 and EO 

105, occurs within the Action Area but is not intersected by the Project footprint. Management 

areas for known occurrences and occupied habitat that are intersected by the Action Area are 

listed below (by CCA Management Area):

• Kuna Management Area - MA 6 / EOs #18, 24, 25, 42, (1051/)
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• Orchard Management Area – MA 8A and 8B / EOs #15, 30, 31, 54, 72, 104

• Mountain Home Management Area – MA 9 / EOs # 51, 62

HIP Transect Number(s):

EO Number HIP Transect Number

15 015

18 018A, 018B, 019A

24 024

25 25

30 030B

31 031

42 042

51 051A, 051B

54 054

62 062

72 072B, 072C

104 072A

105 –1/

1/ No HIP monitoring transect is currently associated with this EO. Monitoring data for EO 42, a nearby EO, are 

used to characterize baseline conditions for this EO in this analysis.
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Potential Effects 

Pathways Indicators

Baseline Indicator Conditions Effect of Action on Indicator Condition

Current Condition Description

Current 

Quality 

Ranking

(H, M, L)

Description of Potential Effects of 

the Action on the Baseline within 

the Action Area

Restore, 

Maintain or 

Degrade 

Habitat

Expected 

Modification 

of Baseline

↑ → ↓

A. Slickspot 

Conditions

A-1. Density of 

nonnative annual 

and/or nonnative 

perennial plants 

established within 

slickspots

Predominantly occupied by 

nonnative invasive species, 

predominantly cheatgrass (Bromus

tectorum).

L Project construction, operation, and 

maintenance increase the potential 

for further spread and proliferation 

of non-native plants and increased 

risk of wildland fire, which may 

affect slickspot peppergrass and 

PCE 1, 2, 3, and 4 of proposed 

critical habitat.

Maintenance roads may be 

beneficial to slickspot peppergrass, 

because two-track maintenance 

roads and bare soil areas 

associated with line structures may 

act as fuel breaks, potentially 

limiting spread of wildfire and 

subsequent spread of weeds. 

Maintenance roads may also 

provide access for fire suppression 

activities. 

Degrade ↓

A-2. Level of ground 

disturbance within 

slickspots 

Observed disturbance is restricted

to livestock compaction and

trampling, ant mound and badger

burrow establishment, and invasive

species encroachment. However,

few of the slickspots demonstrated

the cryptogamic crusts

characteristic of pristine slickspots.

M Soil compaction and soil 

disturbance stemming from 

construction activities and overland 

travel of construction and 

maintenance vehicles, where 

slickspots are not avoidable, may 

affect slickspot peppergrass and 

PCE 1 of proposed critical habitat.

Degrade ↓
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Potential Effects 

Pathways Indicators

Baseline Indicator Conditions Effect of Action on Indicator Condition

Current Condition Description

Current 

Quality 

Ranking

(H, M, L)

Description of Potential Effects of 

the Action on the Baseline within 

the Action Area

Restore, 

Maintain or 

Degrade 

Habitat

Expected 

Modification 

of Baseline

↑ → ↓

A. Slickspot 

Conditions

(continued)

A-3. Level of organic 

debris and/or soil 

deposition and 

accumulation within 

slickspots

Most slickspots lacked a late seral

cryptogamic crust and consisted of

a moderate to high proportion of 

bare soil; lack of crust is most likely

attributable to wildfire as opposed

to aeolian or fluvial deposition. 

Where invasive species

encroachment occurred, organic

debris deposition was a 

subsequent byproduct.

L The proposed action is expected to 

impose minimal soil deposition 

effects on slickspots. There is 

potential for increased spread and 

proliferation of invasive species 

which may indirectly increase 

organic debris deposition in 

slickspot microsites over time, 

which may affect slickspot 

peppergrass and PCE 1 of 

proposed critical habitat. However, 

this increase in organic debris 

deposition is expected to be so 

small it cannot be meaningfully 

measured, detected, or evaluated.

Maintain →

B. Habitat 

Characteristics 

within the 

Action Area 

Surrounding 

Occupied 

Slickspots

B-1. Level of ground 

disturbance within the 

action area

In areas where the corridors are 

situated along existing roads, 

ground disturbance can be 

significant. In areas away from 

existing roads, ground disturbance 

is restricted to residual wildfire 

impacts and typical post-wildfire 

grazing impacts.

L As described above (A-2), some soil 

disturbance could occur from 

Project construction, operation, and 

maintenance. Although relatively 

minor in scale, permanent impacts 

associated with road improvement 

and construction, as well as tower 

placement, will impose irreversible 

negative effects to the landscape by 

effectively transferring the land use. 

Degrade ↓
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Potential Effects 

Pathways Indicators

Baseline Indicator Conditions Effect of Action on Indicator Condition

Current Condition Description

Current 

Quality 

Ranking

(H, M, L)

Description of Potential Effects of 

the Action on the Baseline within 

the Action Area

Restore, 

Maintain or 

Degrade 

Habitat

Expected 

Modification 

of Baseline

↑ → ↓

B. Habitat 

Characteristics 

(continued)

B-2. Condition of 

native vegetation within 

the action area - Level 

of habitat fragmentation

The condition of native vegetation

is degraded and sparse. Small

pockets of sagebrush exist and

Sandberg bluegrass (the latter 

likely a function of overgrazing). 

Intact communities of purple threeawn exist in good condition but 

occur few and far between on 

steeper, south-facing. Habitat 

fragmentation is demonstrable and 

widespread. Much of the area has 

been fragmented due to past 

wildfires, with pockets of shrubs in 

both potential and occupied habitat 

within the action area.

L Assume there will be some loss of 

native shrub cover within the 

construction footprint of the project 

as well as during some Project 

maintenance activities, which could 

impact the species as well as PCEs 

2 and 4 of proposed critical habitat.

Degrade ↓

B-3. Condition of 

native vegetation within 

the action area -

presence of nonnative 

annuals and/or 

nonnative perennial 

plants

The presence of non-native 

species is prevalent and 

widespread and represents the 

overall characterization of the 

Action Area.

L The proposed action has potential 

to increase the spread and 

proliferation of non-native species, 

particularly annual species, which 

may affect the species as well as 

PCEs 2, 3, and 4 of proposed 

critical habitat.

Degrade ↓

B-4. Condition of 

native vegetation within 

the action area - % 

cover of biological soil 

crusts

In association with residual native

vegetation, biological soil crusts

exhibit higher than expected cover. 

However, outside of these native

pockets, crust cover is minimal and

of an early seral state.

L Assume some loss of biological soil 

crust forb cover within the 

construction footprint of the project 

as well as during some Project 

maintenance activities, which could 

impact the species as well as PCE 

2 of proposed critical habitat.

Degrade ↓
Biological Assessment Gateway West Transmission Line Project

March 2013 A-7

Potential Effects 

Pathways Indicators

Baseline Indicator Conditions Effect of Action on Indicator Condition

Current Condition Description

Current 

Quality 

Ranking

(H, M, L)

Description of Potential Effects of 

the Action on the Baseline within 

the Action Area

Restore, 

Maintain or 

Degrade 

Habitat

Expected 

Modification 

of Baseline

↑ → ↓

B. Habitat 

Characteristics

(continued)

B-5. Condition of 

native vegetation within 

the action area - % 

cover of native forbs

The presence of non-native 

species is widespread and 

represents the overall 

characterization of the Action Area.

Native forb cover is 

correspondingly low.

Assume some loss of native forb 

cover within the construction 

footprint of the project as well as 

during some Project maintenance 

activities, which could impact the 

species as well as PCEs 2, 3, and 4 

of proposed critical habitat.

Degrade ↓

SUMMARY Summary of Overall Status of 

Baseline within the Action Area

Thirteen EOs (including occupied 

habitat of 2 EOs) currently exist 

within the Action Area. Five of 

these would be intersected by the 

Project footprint. EOs within the 

Action Area include two as F 

(failed to find), one as “B”, seven

as “C”, two as “D”, and one as 

“BD”. EOs intersected by the 

Project footprint are ranked as: F 

(2), C (3), and B (1).

The presence of non-native 

species is prevalent and 

widespread and condition of native 

vegetation is degraded and 

sparse. Observed disturbance; 

however, is restricted to livestock 

compaction and trampling, ant 

mound and badger burrow 

establishment, and invasive 

species encroachment. However, 

few of the slickspots demonstrate 

the cryptogamic crusts 

characteristic of pristine slickspots.

L Summary of Potential Effects of 

the Action on the Baseline within 

the Action Area

Project construction, operation, and 

maintenance increase the potential 

for further spread and proliferation 

of non-native plants and increased 

risk of wildland fire, which may 

affect slickspot peppergrass and 

PCEs 1, 2, 3, and 4 of proposed 

critical habitat. Additionally, soil 

compaction, soil disturbance, loss of 

native vegetation, and disturbance 

or loss of biological crusts due to 

construction and operation and 

maintenance activities may occur 

and may affect slickspot 

peppergrass, slickspot peppergrass 

habitat and PCEs 1, 2, 3, and 4 of 

proposed critical habitat. 

Permanent impacts to slickspots; 

however, are expected to be 

relatively minor in scale. 

Degrade ↓
Biological Assessment Gateway West Transmission Line Project

March 2013 A-8

Dichotomous Key for Effects Determinations

Lepidium papilliferum Conference Framework

Dichotomous Key for Effects Determinations

1. Are there documented occurrences of Lepidium papilliferum or proposed or designated 

critical habitat, or is potential habitat or slickspot peppergrass habitat present in the 

Action Area? 

A. NO No Effect–Conference is not necessary

B. YES Go to #2

2. Does the Effects Determination Checklist show any effect whatsoever on the species 

and/or its critical habitat or on potential habitat or slickspot peppergrass habitat resulting 

from the action?

A. NO No Effect–Conference is not necessary

B. YES Go to #3

3. Does the Effects Determination Checklist show any potential change 

(degradation/restoration or downward/upward trends) in any of the Matrix Indicators 

resulting from the action?

A. NO No Effect–Conference is not necessary

B. YES Go to #4

4. Is there a negative effect of the action on any Matrix Indicators that is able to be 

meaningfully measured, detected, or evaluated OR is reasonable certain to occur to 

individuals or populations of Lepidium papilliferum or its habitat (i.e., critical habitat 

Primary Constituent Elements, potential habitat, slickspot peppergrass habitat) within the 

Action Area?

A. NO May Affect, is Not Likely to Adversely Affect–Informal 

Conference with the Service is advised

B. YES May Affect, is Likely to Adversely Affect – Formal Conference

with the Service is advised
Biological Assessment Gateway West Transmission Line Project

March 2013 A-9

PCE/Pathway Indicator Crosswalk for Slickspot Peppergrass

PCE PCE Description Corresponding Pathway Indicator

1 Ecologically functional microsites or 

“slickspots” that are characterized by: 

(a) a high sodium and clay content and 

a three-layer soil horizonation and (b) 

sparse vegetation with low to moderate 

introduced plant species cover

A-1. Density of nonnative annual and/or nonnative 

perennial plants established within slickspots

A-2. Level of ground disturbance within slickspots

A-3. Level of organic debris (litter or feces) and/or 

soil deposition and accumulation within 

slickspots

2 Relatively intact native Wyoming big 

sagebrush vegetation assemblages 

within 820 feet (250 meters) of 

slickspots

B-1. Level of ground disturbance within the action 

area

B-2. Condition of native vegetation within the 

action area - level of habitat fragmentation

B-3. Condition of native vegetation within the 

action area - presence of nonnative annuals 

and/or nonnative perennial plants

B-4. Condition of native vegetation within the 

action area - percent cover of biological soil 

crusts

B-5. Condition of native vegetation within the 

action area - percent cover of native forbs

3 A diversity of native plants for insect 

pollinator habitat requirements

B-3 and B-5

4 Sufficient pollinators for successful fruit 

and seed production

B-1, B-2, B-3, and B-5
Biological Assessment Gateway West Transmission Line Project

March 2013

ATTACHMENT B

LIMITING FACTORS ANALYSIS FOR BULL TROUT CRITICAL 

HABITAT 
Biological Assessment Gateway West Transmission Line Project

March 2013 B-1

Bruneau River Environmental Baseline Summary and Anticipated Effects of the Gateway 

West Transmission Project on Bull Trout and its Critical Habitat 

Watershed Condition 

Indicator Pathways

Environmental Baseline 

Condition Effects of the Action

Indicator Properly

Functioning 

Functioning

at Risk

Not Properly 

Functioning Restore Maintain Degrade

SPECIES

Subpopulation 

Characteristics 

Within 

Subpopulation 

Watersheds

Subpopulation size X X 

Growth and survival X X

Life history diversity 

and isolation X X

Subpopulation trend* X

Persistence and genetic 

integrity X X

HABITAT

Water Quality

Temperature X X

Sediment/Turbidity X X+

Chemical 

contamination/nutrients X X

Habitat 

Access Physical barriers X X

Habitat 

Elements

Substrate

embeddedness in 

rearing areas

X X+

Large woody debris* X^

Pool frequency X X

Pool quality* X

Off-channel habitat* X

Refugia* X

Channel 

Condition & 

Dynamics

Wetted width/maximum 

depth ratio in scour 

pools in a reach*

X

Streambank condition X X

Floodplain connectivity* X

Flow/

hydrology

Change in peak/base 

flows* X

Increase in drainage 

network* X

Watershed 

conditions

Road density & 

location* X

Disturbance history* X

Riparian Habitat 

Conservation Area* X^

Disturbance regime* X

Integration of 

species and 

habitat*

X

* = No environmental baseline data available

+ = Some sediment may be introduced into the Bruneau River, but effects to primary constituent elements 

of bull trout critical habitat are expected to be insignificant (so small that they cannot be meaningfully 

measured, detected, or evaluated).

^ = A few individual trees may be removed from the Riparian Habitat Conservation Area, but effects to 

primary constituent elements of bull trout critical habitat are expected to be insignificant (so small that 

they cannot be meaningfully measured, detected, or evaluated).