REVISED RECOVERY PLAN 

FOR THE 

PAIUTE CUTTHROAT TROUT

(Oncorhynchus clarki seleniris)

Original Approved: January 25, 1985

Region 1

U. S. Fish and Wildlife Service

Portland, Oregon
i

DISCLAIMER

Recovery plans delineate reasonable actions that are believed to be

required to recover and/or protect listed species. We, the U.S. Fish and Wildlife

Service, publish recovery plans, sometimes preparing them with the assistance of

recovery teams, contractors, State agencies, and other affected and interested

parties. Objectives of the recovery plan will be attained and any necessary funds

made available subject to budgetary and other constraints affecting the parties

involved, as well as the need to address other priorities. Recovery plans do not

obligate other parties to undertake specific tasks and may not represent the views

nor the official positions or approval of any individuals or agencies involved in

recovery plan formulation, other than our own. They represent our official

position only after they have been signed by the California/Nevada Operations

Manager, Regional Director, or Director as approved. Recovery plans are

reviewed by the public and submitted to additional peer review before we adopt

them as approved final documents. Approved recovery plans are subject to

modification as dictated by new findings, changes in species status, and the

completion of recovery actions.

LITERATURE CITATION SHOULD READ AS FOLLOWS:

U.S. Fish and Wildlife Service. 2004. Revised Recovery Plan for the Paiute

cutthroat trout (Oncorhynchus clarki seleniris). Portland, Oregon. ix +

105 pp.

An electronic version of this recovery plan will also be made available at

http:/pacific.fws.gov/ecoservices/endangered/recovery/plans.html and

http://endangered.fws.gov/recovery/index.html.
ii

ACKNOWLEDGMENTS

We gratefully acknowledge the commitment and efforts of the following

individuals to the recovery of the Paiute cutthroat trout. Without their assistance,

this revision would not have been possible.

Dawne Becker, California Department of Fish and Game

Brian Finlayson, California Department of Fish and Game

Eric Gerstung, California Department of Fish and Game

Jim Harvey, U.S. Forest Service, Humboldt-Toiyabe National Forest

Stafford Lehr, California Department of Fish and Game

Lisa Sims, U.S. Forest Service, Inyo National Forest

Pat Shanley, U.S. Forest Service, Humboldt-Toiyabe National Forest

William Somer, California Department of Fish and Game

Stan Stephens, California Department of Fish and Game

Phil Strand, U.S. Forest Service, Sierra National Forest

Darrell Wong, California Department of Fish and Game
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EXECUTIVE SUMMARY

Background: The Silver King Creek drainage is located on the eastern slope of

the Sierra Nevada Range, in Alpine County, California. It is a major tributary to

the East Fork of the Carson River, which drains into the Lahontan Basin. It

provides habitat for one fish species, Paiute cutthroat trout (Oncorhynchus clarki

seleniris), that is listed as threatened under the Endangered Species Act of 1973, as

amended. It also provides known or potential habitat for two amphibian candidate

species, the Sierra Nevada population of the mountain yellow-legged frog (Rana

muscosa) and the Yosemite toad (Bufo canorus). All Paiute cutthroat trout

recovery actions were evaluated to minimize adverse impacts to the frog and toad.

Current Species Status: The Paiute cutthroat trout was originally listed as

endangered on March 11, 1967 (U.S. Fish and Wildlife Service 1967) under the

Endangered Species Preservation Act of 1966. On July 16, 1975, Paiute cutthroat

was reclassified as threatened under the Endangered Species Act of 1973 (U.S.

Fish and Wildlife Service 1975) to facilitate management and allow regulated

angling. It currently occupies approximately 18.6 kilometers (11.5 miles) of

historically fishless stream habitat in the Silver King drainage above Llewellyn

Falls and above a barrier in Corral and Coyote Creeks (Figures 1 and 2). Four 

self-sustaining, genetically pure populations of Paiute cutthroat trout are known to

occur out-of-basin in the North Fork of Cottonwood Creek, Stairway Creek,

Sharktooth Creek, and Cabin Creek (Figures 1, 3, and 4). 

Recovery Priority: The Paiute cutthroat trout has a recovery priority number of 9,

per criteria published by a Federal Register notice in 1983 (U.S. Fish and Wildlife

Service 1983). This priority number indicates a subspecies with moderate degree

of threat and a high potential for recovery.

Habitat requirements: The life history and habitat requirements for Paiute

cutthroat trout are similar to those reported for other western stream-dwelling

salmonids. All life stages require cool, well-oxygenated waters. Adult fish prefer

stream pool habitat in low gradient meadows with undercut or overhanging banks

and abundant riparian vegetation. Paiute cutthroat trout can survive in lakes, but

there is no evidence that they ever occurred naturally in any of the lakes within the
iv

Silver King basin. To spawn successfully, they must have access to flowing

waters with clean gravel substrates. 

Recovery Goal: Recovery of Paiute cutthroat trout sufficient to allow delisting

of the species.

Recovery Objectives: Improve the status and habitat of Paiute cutthroat trout

and eliminate competition from nonnative salmonid species.

Recovery Criteria: Paiute cutthroat trout will be considered for delisting when

the following objectives are met:

1) All nonnative salmonids are removed from Silver King Creek and its

tributaries downstream of Llewellyn Falls to fish barriers in Silver King

Canyon;

2) A viable population occupies all historic habitat in Silver King Creek and

its tributaries downstream of Llewellyn Falls to fish barriers in Silver

King Canyon; 

3) Paiute cutthroat trout habitat is maintained in all occupied streams; 

4) The refuge populations in Corral and Coyote Creeks, Silver King Creek,

and tributaries above Llewellyn Falls as well as out-of-basin populations

are maintained as refugia and are secured from the introduction of other

salmonid species; and

5) A long-term conservation plan and conservation agreement are developed,

which will be the guiding management documents once Paiute cutthroat

trout are delisted. 
v

Recovery Actions:

1. Remove nonnative trout from historic Paiute cutthroat trout habitat.

2. Reintroduce Paiute cutthroat trout into historic habitat.

3. Protect and enhance all occupied Paiute cutthroat trout habitat.

4. Continue to monitor and manage existing and reintroduced populations.

5 Develop a long-term conservation plan and conservation agreement. 

6. Provide public information.

Implementation Participants: The California Department of Fish and Game

and the U.S. Forest Service will assist the U.S. Fish and Wildlife Service in

implementing recovery tasks.

Total Estimated Cost of Recovery ($1,000's):

Year Action 1 Action 2 Action 3 Action 4 Action 5 Action 6

2004 38 -- 2 19.73 -- 2.9

2005 31 -- 49.5 31.23 -- 2.9

2006 31 -- 51.1 38.31 -- 2.9

2007 -- 8 37 20.73 -- 2.9

2008 -- 8 4.08 20.73 -- 0.4

2009 -- 8 3.6 23.81 -- --

2010 -- 8 2 20.73 6 --

2011 -- 8 2 20.73 6 --

2012 -- -- 3.6 20.81 -- --

2013 -- -- 4.08 18.73 -- --

 

TOTAL 100 40 158.95 235.5 12 12

The total estimated cost of recovering Paiute cutthroat trout is $558,450, plus

additional costs that cannot be estimated at this time.

Date of Recovery: Delisting of the Paiute cutthroat trout could be initiated in

2013, if tasks are implemented as recommended and recovery criteria are met.
vi

TABLE OF CONTENTS

I. INTRODUCTION ..............................................1

A. Brief Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

B. Species Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

C. Associated Candidate Species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

1. Sierra Nevada Population of Mountain Yellow-legged Frog . . 7

2. Yosemite Toad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

D. Life History and Habitat Requirements . . . . . . . . . . . . . . . . . . . . . . . 10

E. Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

F. Abundance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

1. Silver King Creek Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . 16

2. North Fork of Cottonwood Creek . . . . . . . . . . . . . . . . . . . . . . 23

3. Cabin Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

4. Stairway Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

5. Sharktooth Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

G. Habitat Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

1. Silver King Creek Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . 27

2. North Fork of Cottonwood Creek . . . . . . . . . . . . . . . . . . . . . . 32

3. Cabin Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

4. Stairway Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

5. Sharktooth Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

H. Reasons for Listing and Current Threats . . . . . . . . . . . . . . . . . . . . . . 41

I. Conservation Efforts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

II. RECOVERY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

A. Objective and Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

B. Recovery Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

C. Narrative Outline of Recovery Actions . . . . . . . . . . . . . . . . . . . . . . . 52

III. IMPLEMENTATION SCHEDULE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65

IV. REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

A. Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

B. In Litt. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79

C. Personal Communications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
vii

APPENDIX A. Summary of General Aquatic Wildlife System (GAWS)

Survey Locations, Sediment Sampling, and

Macroinvertebrate Sampling . . . . . . . . . . . . . . . . . . . . A-1

APPENDIX B. Summary of Threats and Recommended Recovery Actions

for the Paiute Cutthroat Trout . . . . . . . . . . . . . . . . . . . . B-1

APPENDIX C. Summary of Comments on the Draft Revised Recovery

Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1

LIST OF TABLES

Table 1. Recorded Transplants of Paiute Cutthroat Trout . . . . . . . . . . . . . 17

Table 2. Physical Characteristics of Silver King Creek and its Principal 

Tributaries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Table 3. Summary of Habitat Condition Index (HCI) Ratings from 1984,

1987, and 1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

Table 4. Common and scientific names of the riparian plant communities in

the Silver King Creek drainage . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Table 5. Summary of Habitat Survey on Stairway Creek Conducted in 

1996. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 6. Cross Sectional Data From 2000 Survey of Stairway Creek . . . . 37

Table 7. Transect Data From 2000 Survey of Stairway Creek . . . . . . . . . 38

Table 8. Cross Sectional Data From 1999 Survey of Sharktooth Creek . . 40

Table 9. Transect Data From 1999 Survey of Sharktooth Creek . . . . . . . . 40
viii

Table A1. Summary of GAWS station site characteristics . . . . . . . . . . . . A-1

Table A2. Summary of sediment samples collected in 1984 and 1990 . . A-4

Table A3. Summary of macroinvertebrate diversity index (DAT) ratings from

1984, 1987, and 1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-5

Table A4. Summary of macroinvertebrate standing crop data from 1984, 

1987, and 1990 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-6

Table A5. Summary of macroinvertebrate Biotic Condition Index (BCI)

ratings from 1984, 1987, and 1990 . . . . . . . . . . . . . . . . . . . . . A-7

Table B1. Summary of Threats and Recommended Recovery Actions . . . B-1

LIST OF FIGURES

Figure 1. Distribution of Paiute cutthroat trout in east-central California . . 2

Figure 2. Silver King Creek and its tributaries, Humboldt-Toiyabe 

National Forest, Alpine County, California ..................5

Figure 3. North Fork Cottonwood Creek and Cabin Creek, Inyo 

National Forest, Mono County, California. . . . . . . . . . . . . . . . . . 18

Figure 4. Stairway Creek, Madera County and Sharktooth Creek, Fresno

County, California, Sierra National Forest. . . . . . . . . . . . . . . . . . 19

Figure 5. Historical population estimates (1964 to 2001) from the Upper 

Fish Valley reach of Silver King Creek. . . . . . . . . . . . . . . . . . . . 21

Figure 6. Historical population estimates (1964 to 2000) from Four Mile 
ix

Creek. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Figure 7. Historical population estimates (1984 to 2000) from Fly 

Valley Creek. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 8. Historical population estimates (1974 to 2000) from Corral 

Valley Creek.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Figure 9. Historical population estimates (1984 to 2000) from Coyote 

Valley Creek . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Figure 10. Visual observations from the North Fork of Cottonwood 

Creek since 1989. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Figure A1. Location of GAWS stations on Silver King, Four Mile Canyon, 

Fly Valley, and Bull Canyon Creeks . . . . . . . . . . . . . . . . . . . . A-2

Figure A2. Locations of GAWS stations on Corral Valley and Coyote Valley 

Creeks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
1

I. INTRODUCTION 

A. Brief Overview

The Paiute cutthroat trout (Oncorhynchus clarki seleniris) is native to

Silver King Creek in the East Fork Carson River drainage on the HumboldtToiyabe National Forest, Alpine County, California. This basin also provides

known or potential habitat for two amphibian candidate species, the Sierra

Nevada population of the mountain yellow legged frog (Rana muscosa) and the

Yosemite toad (Bufo canorus). Paiute cutthroat trout evolved in isolation from

other fish species in this headwater tributary of the Lahontan Basin. 

The Paiute cutthroat trout was originally listed as endangered on March

11, 1967 (U.S. Fish and Wildlife Service 1967) under the Endangered Species

Preservation Act of 1966. On July 16, 1975, the Paiute cutthroat trout was

reclassified as threatened under the Endangered Species Act of 1973 (U.S. Fish

and Wildlife Service 1975) to facilitate management and allow regulated angling.

Critical habitat has not been designated for this species. The historical

distribution of Paiute cutthroat trout is thought to have been limited to Silver King

Creek and its tributaries below an impassable barrier (Llewellyn Falls) to

downstream barriers located in Silver King Canyon. In the early part of the

twentieth century they were eliminated from their presumed historic habitat

through hybridization with introduced rainbow trout (Oncorhynchus mykiss),

golden trout (Oncorhynchus mykiss aguabonita), and Lahontan cutthroat trout

(Oncorhynchus clarki henshawi). Their range was extended into the upper

reaches of Silver King Creek and its tributaries by one or more unofficial

transplants of fish above Llewellyn Falls starting in 1912. 

The current distribution of Paiute cutthroat trout within the Silver King

Creek drainage is the upper reaches of Silver King Creek and its tributaries above

Llewellyn Falls, and Corral Valley and Coyote Valley Creeks below Llewellyn

Falls. The progeny of these early day transplants have been introduced into

several other lakes and streams in California and at least four self-sustaining

populations have become established outside the historic drainage (Figure 1). 

The four out-of-basin populations occur in the North Fork of Cottonwood Creek
Figure 1. Distribution of Paiute cutthroat trout in east-central California, showing locations of 

currently occupied streams (yellow circles) and introductions that have failed or introgressed with 

other trout species (red circles).

Silver King Creek

Delaney Creek

Birchim Lake

Leland Lakes

Cabin Creek

North Fork 

Cottonwood Creek

Stairway Creek

Sharktooth Creek

McGee Creek

Heenan Lake

Bull Lake

2
3

 and Cabin Creek (Inyo National Forest, Mono County, California), Sharktooth

Creek (Sierra National Forest, Fresno County, California), and Stairway Creek

(Sierra National Forest, Madera County, California). To prevent the extinction of

this fish and to attain its recovery, all viable extant populations must be

maintained and secured, nonnative fish must be removed from historic habitat,

and Paiute cutthroat trout must be successfully reintroduced into Silver King

Creek from Llewellyn Falls downstream to Silver King Canyon.

A recovery plan for the Paiute cutthroat trout was prepared in 1985 (U.S.

Fish and Wildlife Service 1985). The objectives of the 1985 recovery plan were

to reestablish a pure population of Paiute cutthroat trout in Silver King Creek

above Llewellyn Falls, and secure and maintain the integrity of the occupied

habitats in Silver King Creek, North Fork Cottonwood Creek, and Stairway

Creek, all which occur outside of the presumed historic habitat. The 1985

recovery plan did not address recovering Paiute cutthroat in its historic habitat

because it was not known that natural barriers existed which would prevent

upstream migration of non-native salmonids into historic habitat. This revised

recovery plan will incorporate recent research data and address the species’

current status, threats, distribution, and recovery needs. It also addresses the

effects of recovery actions on the mountain yellow-legged frog and Yosemite

toad, both of which occur within the Silver King Creek drainage and at the sites

of the out-of-basin populations. All Paiute cutthroat trout recovery actions have

been evaluated to minimize adverse impacts to the frog and toad. In keeping with

our current policy (U.S. Fish and Wildlife Service and National Oceanic and

Atmospheric Administration 1994), this recovery plan identifies tasks to maintain

ecosystem integrity as well as recover the listed species.

Based on new information and completed tasks, we have determined it is

necessary to revise recovery criteria and tasks within the 1985 Paiute cutthroat

trout recovery plan. The new information and completed tasks include: 1) the

discovery of fish barriers downstream of Llewellyn Falls that would enable the

expansion of Paiute cutthroat trout into historic habitat, 2) elimination and

reduction of threats to existing populations, 3) increased knowledge about Paiute

cutthroat trout population dynamics based on long-term trend data, and
4

4) information about the current status of out-of-basin populations based on

recent population estimates. 

The extremely limited native range of the Paiute cutthroat trout,

approximately 14.7 kilometers (9.1 miles) of stream habitat within a single

watershed (Figure 2), is the primary factor in identifying recovery tasks. Potential

recovery activities within the native range include the reintroduction of Paiute

cutthroat trout downstream from Llewellyn Falls to Silver King Canyon once

nonnative fish have been removed, and the protection of stream habitat in the

Silver King Creek watershed. If the Paiute cutthroat trout occurred only in its

currently occupied habitat, it would be highly vulnerable to extinction because: 

1) genetic diversity could be dramatically reduced by a catastrophic event within

any of the five drainages it currently occupies, 2) populations could become

quickly introgressed (lose their distinctiveness due to introduction of genes from

another population into the gene pool) as the result of an unauthorized

introduction of other salmonids, and 3) genetic diversity could be subjected to

additional severe bottlenecks due to inadequate population size. However,

reintroduction of Paiute cutthroat trout to historical habitat, in combination with

populations existing upstream of Llewellyn Falls and out-of-basin, will

substantially reduce these extinction threats. 

B. Species Description 

The Paiute cutthroat trout is a distinctive member of the cutthroat trout

complex, distinguishable from other cutthroat trouts by body coloration and the

absence, or near absence, of body spots. Snyder (1933, 1934) described these fish

as a new species, (Salmo seleniris), based on: 1) absence of body spots, 2)

slender body form, 3) relatively small scales, and 4) vivid coloration. Subsequent

comparisons of the type specimens with other cutthroat subspecies (Ryan and

Nicola 1976, Behnke 1980) revealed that the meristic (relating to number and

relation of body parts) and morphometric (relating to measurement of external

form) characters for Paiute cutthroat trout are also typical of those characterizing

Lahontan cutthroat trout. In recognition of the similarity of Paiute cutthroat trout 
Figure 2. Historic (blue) and currently occupied (red) habitat for Paiute cutthroat trout in 

Silver King Creek, Humboldt-Toiyabe National Forest, Alpine County, California.

5
6

and other cutthroat subspecies, Vestal (1947) relegated the Paiute cutthroat trout

to a subspecies of Salmo clarki. Miller (1950) and Shapovalov and Dill (1950)

accepted this reclassification and it was recognized as Salmo clarki seleniris. All

western North American trout have been reclassified from the genus Salmo to the

genus Oncorhynchus, as summarized by Smith and Stearly (1989) and adopted by

the American Fisheries Society’s Committee on Names of Fishes (Robins et al.

1991).

Behnke and Zarn (1976) concluded, on the basis of gillraker comparisons,

that the separation of Paiute cutthroat from Lahontan cutthroat occurred relatively

recently (no more than 5,000 to 8,000 years ago), following the desiccation of

Lake Lahontan. Paiute cutthroat trout and Lahontan cutthroat trout both typically

possess 150 to 180 lateral series scales, 60 to 63 total vertebrae, 50 to 70 pyloric

caeca (finger-like projections of the small intestine), and 21 to 27 gill rakers

(bony projections from the gill arches). In the past, it was not possible to

distinguish between the two subspecies on the basis of electrophoretic analytical

techniques (Busack and Gall 1981). However, development of diagnostic DNA

microsatellite markers may provide discrimination in the future (B. May,

University of California, Davis, California, pers. comm. 2001).

Body spotting is the primary diagnostic character distinguishing the Paiute

cutthroat trout from the Lahontan cutthroat trout. Paiute cutthroat trout have been

known to have up to 9 body spots, but rarely more than 5, whereas Lahontan

cutthroat trout typically possess 50 to 100 body spots and may have more. A

secondary, but unquantifiable, distinguishing character is body coloration. Paiute

cutthroat trout are typically coppery to purplish-pink, whereas Lahontan cutthroat

trout from comparable stream environments are normally silver-yellow to light

green. 

C. Associated Candidate Species

In addition to Paiute cutthroat trout, two amphibian species that are

candidates for listing, the mountain yellow-legged frog (Rana muscosa) and

Yosemite toad (Bufo canorus), are known to occur in the Silver King Creek

drainage.
7

1. Sierra Nevada Population of Mountain Yellow-legged Frog

On October 12, 2000, we published a 90-day finding for a petition to list

the Sierra Nevada population of the mountain yellow-legged frog under the

Endangered Species Act (U.S. Fish and Wildlife Service 2000a). We found the

petition to have substantial evidence that listing the species as endangered may be

warranted. We subsequently prepared a 12-month finding on the petition to list

the Sierra Nevada population of the mountain yellow-legged frog. This finding

was published in the Federal Register on January 16, 2003 (U.S. Fish and

Wildlife Service 2003). We found that proposing to list this population was

warranted but precluded by higher priority listing actions, and the population is

now considered a candidate for listing. The southern California population of the

mountain yellow-legged frog, which is currently listed as endangered, does not

occur within the range of the Paiute cutthroat trout.

The mountain yellow-legged frog is a member of the family Ranidae (true

frogs). It is a medium-sized frog with adults reaching 50 to 80 millimeters (2.0 to

3.1 inches) in length. The species attains lengths of 67 millimeters (2.6 inches) in

males and 80 millimeters (3.1 inches) in females (Zweifel 1955, 1968). Their

undersides range from a cream color to brilliant yellow. Dorsal coloration varies

from drab olive to dark brown, with patterns ranging from discrete dark spots that

can be few and large, to smaller and more numerous spots with a mixture of size

and shapes. Tadpoles reach up to 76 millimeters (3.0 inches) in size and take from

2 to 4 years to metamorphose. Male frogs can smell strongly of garlic during the

breeding season. The call of the male frogs is rarely heard because they vocalize

while underwater.

Within the Silver King Creek drainage, mountain yellow-legged frogs

have been observed along the mainstem in Upper Fish Valley, the artificial

channel in Upper Fish Valley, the lower portion of Fly Valley Creek, and at

Whitecliff Lake. As recently as 1993, several thousand mountain yellow-legged

frogs were observed in the Silver King Creek drainage along the shores of

Whitecliff Lake (P. Shanley, U.S. Forest Service, pers. comm. 2000). Prior to

2001, mountain yellow-legged frog occurrence information was primarily

gathered during fish survey or management activities. In the summer of 2001, the
8

California Department of Fish and Game conducted a drainage-wide survey for

amphibians. No adult mountain yellow-legged frogs were observed at Whitecliff

Lake or other areas within the Silver King Creek drainage. However, two

mountain yellow-legged frog tadpoles were observed in an artificial channel

created as rearing habitat for Paiute cutthroat trout in Upper Fish Valley. In 2002,

three adult mountain yellow-legged frogs were observed above Llewellyn Falls in

the course of Paiute cutthroat trout surveys.

Chango and Wolf Creek Lakes, south of the Silver King Creek drainage in

the West Walker River drainage, historically supported mountain yellow-legged

frogs. Chango Lake is approximately 4.0 kilometers (2.5 miles) from upper

Silver King Creek. Wolf Creek Lake is approximately 4.8 kilometers (3.0 miles)

from upper Silver King Creek. In 1999, approximately 200 adult and 300 larval

frogs were seen at Chango Lake (P. Shanley, pers. comm. 2000). An early survey

in 2001 at Chango Lake yielded no mountain yellow-legged frogs. However, in a

follow-up late-season survey, a total of 3 adults and 95 tadpoles were observed

(D. Becker, California Department of Fish and Game, pers. comm. 2001). The

population in Wolf Creek Lake is believed to be extirpated. 

A conservation assessment and strategy program has been initiated for the

mountain yellow-legged frog. A draft assessment has been prepared by the U.S.

Forest Service, in cooperation with State and Federal agencies, universities, and

research scientists, but has not yet been finalized. This conservation assessment

will synthesize the best available information, including life history, habitat

association, and risk factors and identify occupied and unoccupied habitats

essential for the conservation of the species (U.S. Forest Service 2001).

2. Yosemite Toad

On October 12, 2000, we published a 90-day finding for the petition to list

the Yosemite toad (U.S. Fish and Wildlife Service 2000b). We found the petition

to have substantial evidence that listing the species as endangered may be

warranted. Our 12-month finding on the petition to list the Yosemite toad was

published in the Federal Register on December 10, 2002 (U.S. Fish and Wildlife

Service 2002). We found that proposing to list the Yosemite toad was warranted,
9

but precluded by higher priority listing actions; the species is now considered a

candidate for listing. 

The Yosemite toad is a high elevation species that occurs in the central

Sierra Nevada Range (Stebbins 1966). Within the Silver King Creek drainage,

the range of the Yosemite toad and western toad (Bufo boreas) overlap, and some

degree of hybridization is suspected to occur. The Yosemite toad is a close

relative of three toad species, the western toad, black toad (B. exsul), and

Amargosa toad (B. nelsoni) (Blair 1972, Stebbins 1966). Yosemite/western toad

hybridization occurs in the northern portion of the Yosemite toad’s range in the

Blue Lake region of the Carson-Iceberg Wilderness, just southeast of Carson Pass

in Alpine County (Karlstrom 1962, Stebbins 1966). The Yosemite toad is a small

to medium-sized toad with no head crests and large, flat circular parotoid glands

(warty poison glands on the head) that are slightly separated (Karlstrom 1962). 

Yosemite toads show a high degree of sexual dimorphism (differing appearance

of males and females). Females are larger and darker colored, with irregular dark

blotches bordered with white, and males are smaller and speckled with black

spots on a dull yellow to olive-greenish background and without distinct dark

patches on their back (Karlstrom 1962). 

A California Department of Fish and Game summer amphibian survey in

2001 documented occurrence of Yosemite toads, western toads, and hybrid

Yosemite/western toads in the Silver King Creek drainage. Yosemite toads have

also been observed in Silver Creek Meadows, which is situated below Chango

Lake, in the West Walker River drainage. No quantitative surveys have been

conducted to assess population size in the Silver King drainage. Additionally, the

Sierra National Forest has been conducting surveys for Yosemite toads for the

past decade. Yosemite toads have been noted in the Stairway Creek drainage in

1996, 2000, and 2001, and at Sharktooth Lake in 1999 (P. Strand, Sierra National

Forest, pers. comm. 2002). A conservation assessment that is similar to efforts by

the U.S. Forest Service for the mountain yellow-legged frog will also be

undertaken for the Yosemite toad.

Other than recent surveys, no specific conservation actions directed

towards the mountain yellow-legged frog and Yosemite toad in the Silver King
10

Creek drainage have been completed. However, several measures including

livestock grazing closures and other habitat improvement projects have likely

benefitted the mountain yellow-legged frog and Yosemite toad. Habitat

improvements to the artificial channel in Upper Fish Valley have been a benefit to

both amphibians. The chemical treatment of Bull Canyon Creek above the falls

to Whitecliff Lake and the cessation of stocking in Tamarack Lake have reduced

the impacts associated with introduced trout.

Prior to treatment to remove introgressed fish below Llewellyn Falls,

amphibian surveys will be conducted on lower Silver King Creek, Tamarack

Lake, Tamarack Creek, and other tributaries entering into the mainstem in that

reach. All amphibians captured in surveys will be relocated during the

treatments. There may be some negative impacts on amphibians if they are not

captured during the relocation process or through stress of handling. However,

the long-term effects of removal of nonnative and hybrid fish will be beneficial to

native amphibians.

Whitecliff Lake, Tamarack Lake, and their outflows will be maintained as

fishless waters. Amphibian populations will be monitored annually and

biological and ecological data will be gathered. An evaluation is expected to be

completed annually following the treatment to determine whether recolonization

is occurring naturally or if the reintroduction from adjacent amphibian

populations is necessary.

Recommendations from the range-wide conservation assessment and

strategy efforts will be incorporated into management activities within the Silver

King Creek drainage. These two amphibian species also co-occur with the four

out-of-basin populations of Paiute cutthroat trout (North Fork Cottonwood,

Stairway, Sharktooth, and Cabin Creeks), and conservation efforts will also be

undertaken at these locations.

D. Life History and Habitat Requirements

Few studies have been completed on the biology of the Paiute cutthroat

trout. Most of what is known is based on studies conducted by Wong (1975) and
11

Diana (1975) on the introduced population in the North Fork of Cottonwood

Creek, Mono County, California. Its life history and habitat requirements appear

to be similar to those reported for other western stream-dwelling salmonids. All

life stages require cool, well-oxygenated waters. Adult fish prefer stream pool

habitat in low gradient meadows with undercut or overhanging banks and

abundant riparian vegetation (Behnke and Zarn 1976). Pools are important

rearing habitat for juveniles and act as refuge areas during winter (Raleigh et al.

1984; Swales et al. 1986; Berg 1994). During the winter months, trout move into

pools to avoid physical damage from ice scouring (Hartman 1965; Scrimgeour et

al. 1994) and to conserve energy (Everest and Chapman 1972; Cunjak 1996). As

with other salmonids, suitable winter habitat may be more restrictive than summer

habitat (Jakober et al. 1998). Paiute cutthroat trout survive in lakes, but there is

no evidence that they ever occurred naturally in any lakes within the Silver King

basin. Paiute cutthroat trout demonstrate fluvial spawning behavior and must have

access to flowing waters with clean gravel substrates. 

Paiute cutthroat trout reach sexual maturity at the age of 2 years. Peak

spawning activity occurs in June and July (Wong 1975). The eggs hatch in 6 to 8

weeks and the fry emerge from the gravel in another 2 to 3 weeks. Young-of-theyear fish rear in mainstem shoals or backwaters, and often move into intermittent

tributary streams until they reach about 50 millimeters (2.0 inches) in length

(Diana and Lane 1978; W. Somer, California Department of Fish and Game, pers.

comm. 2001). 

Paiute cutthroat trout are opportunistic feeders, utilizing whatever aquatic

and terrestrial invertebrates occur in the drift. They set up dominance hierarchies

and defend these positions (Wong 1975). The largest fish typically occupy pools,

while the smaller fish utilize runs and riffles and whatever other unoccupied

habitats are available. Growth rates vary with water temperature and the

abundance of food organisms. In stream environments Paiute cutthroat trout

seldom reach sizes in excess of 250 millimeters (10 inches) total length (Moyle

1976). They attain a maximum size of 342 millimeters (13.5 inches) in Silver

King Creek (W. Somer, pers. comm. 2002). In lakes they may grow to 450

millimeters (18 inches) or more (Ryan and Nicola 1976). 
12

Paiute cutthroat trout eggs and fry have several natural predators -- water

shrews (Sorex palustris), dippers (Cinclus mexicanus), and trichopteron larvae --

but adult fish have few predators. Disease is apparently a significant cause of

adult mortality, particularly in the post-spawning period. Wong (1975) observed

extensive fungal infections on the dorsal and caudal fins of several spawned-out

fish in the North Fork of Cottonwood Creek. Many of these fish were so

weakened by spawning they were unable to recover. This fungal infection has

never been observed outside of North Fork of Cottonwood Creek. Few Paiute

cutthroat trout apparently live beyond the age of 3 years in a wild stream

environment (Wong 1975).

Paiute cutthroat trout are less wary than other trouts, presumably because

they evolved in a high mountain environment where terrestrial and avian

predators are not frequently encountered (Moyle 1976). Their unwariness makes

them highly vulnerable to angling. Significant population declines have been

noted in waters that are exposed to moderate or even light fishing pressure

(MacPhee 1966; Behnke 1980). 

E. Distribution

The presumed historic distribution of the Paiute cutthroat trout is limited

to 14.7 kilometers (9.1 miles) of habitat, in Silver King Creek (from Llewellyn

Falls downstream to Silver King Canyon) as well as the accessible reaches of

three small named tributaries: Tamarack Creek, Tamarack Lake Creek, and the

lower reaches of Coyote Valley Creek downstream of barrier falls (Figure 2). 

This watershed is entirely within the boundaries of the Humboldt-Toiyabe

National Forest. The issue of what constitutes the native range is complicated by

the paucity of early collection records and the conflicting recollections of early

observers. The situation is further complicated by one or more unofficial

transplants, and by natural events that may have altered the course of Silver King

Creek. The account presented here is based on the conclusions of Ryan and

Nicola (1976) and supported by Behnke (1980). 

A barrier or series of barriers that developed in the Silver King Canyon

during the last 10,000 years led to the isolation of Paiute cutthroat trout from
13

Lahontan cutthroat trout. Connell and others reported that a high falls exists on

lower Silver King Creek a short distance upstream from its confluence with

Snodgrass Creek (Ashley 1970). A 1994 California Department of Fish and

Game survey identified six potential fish barriers in the Silver King Canyon, the

two highest being 2.44 meters (8 feet) and 3.05 meters (10 feet) in two separate

channels. 

Steep barrier falls exist at several locations on the mainstem and

tributaries of Silver King Creek. The locations of all known fish barriers in the

Silver King Creek drainage are shown in Figure 2. Llewellyn Falls is assumed to

have been a historic barrier to upstream fish movements in Silver King Creek on

the basis of Virgil Connell's observations and recollections. Connell, an early

grazing permittee in the basin, reported that there were no fish above Llewellyn

Falls in the early 1890's (V. Connell, letter in Ryan and Nicola 1976). In 1912,

Joe Jaunsaras, a herdsman employed by Connell, caught some fish below

Llewellyn Falls and transplanted them into Silver King Creek above the falls (V.

Connell, letter in Ryan and Nicola 1976). According to Connell these (unspotted)

fish increased in numbers above the falls ". . . until in 1924 the stream was so well

stocked, that fishing above the falls was better than below." Connell also noticed

that sometime during this period the fish below the falls became " . . . mixed with

other kinds, probably due to the stocking on the lower stream of different

varieties.” 

An alternative scenario for the introduction of Paiute cutthroat trout into

upper Silver King Creek is presented by Ashley (1970). He concluded, on the

basis of conversations with a herdsman, that the 1912 transplant was a failure and

that the population above Llewellyn Falls became established as the result of an

introduction in 1924. John Jaunsaras, the brother of the herdsman who made the

1912 transplant, reported that he and another man carried 75 5-gallon buckets of

trout upstream around the falls. The fish reportedly originated from a small

tributary of Silver King Creek that entered the mainstem just below Llewellyn

Falls. Ryan and Nicola (1976) rejected this explanation because large numbers of

fish were reported to be present above Llewellyn Falls by Connell in 1924, and

because the purported donor population below Llewellyn Falls may already have
14

become introgressed by 1924. There is no evidence to suggest that the population

above Llewellyn Falls became introgressed anytime before 1949. 

The means by which rainbow trout and Lahontan cutthroat trout gained

access to historic Paiute cutthroat trout habitat, and the date on which it first

occurred, are not known. It may have happened in the mid-1920's as the result of

a flood that changed the course of Silver King Creek. Ashley (1970) accepted

Connell's account of a severe cloudburst in the Silver King Creek drainage in

1927, and concluded that the resultant flood altered the course of Silver King

Creek near its confluence with Snodgrass Creek and eliminated a historic

waterfall. Alternatively, rainbow trout and Lahontan cutthroat trout may have

been introduced by early ranchers or anglers. 

By 1933 when Snyder made his collections in Silver King Creek, the

population below Llewellyn Falls consisted of heavily spotted fish, and the

population above Llewellyn Falls was made up of fish without any, or with only a

small number of, body spots. Of the 79 specimens of Paiute cutthroat trout

collected by Snyder from above Llewellyn Falls in 1933, 47 had no body spots

and the remaining 32 had from 1 to 9 body spots (S. Nicola, pers. comm. in U.S.

Fish and Wildlife Service 1985). 

It is not known if Paiute cutthroat trout are native to Corral Valley Creek

and its tributary Coyote Valley Creek (Figure 2). Falls near the mouth of Corral

Valley Creek are assumed to have been a historic fish barrier. However, there are

no records to confirm that this tributary was originally barren of fish. Ashley

(1970) reported that both Corral Valley and Coyote Valley Creeks contained

Paiute cutthroat trout when Connell first visited the area in 1889. Connell

believed their presence was due to the activities of French-Canadian loggers who

were working in the area in the 1860's (Ashley 1970). Vestal (1947) made the

first documented collections from these two streams in 1946, and believed that the

streams were ". . . formerly barren of fish life." He attributed their presence to the

activities of sheepmen who ". . . reportedly planted Piute (sic) trout a few at a

time in buckets from Upper Fish Valley." 
15

Sometime after 1950, Paiute cutthroat trout in Silver King Creek above

Llewellyn Falls became introgressed as the result of introductions of rainbow and

Lahontan cutthroat trout into the upper watershed by the California Department of

Fish and Game. Planting records indicate that 5,040 rainbow trout fry were

stocked above Llewellyn Falls during September 1949. It is unclear when or

where Lahontan cutthroat trout were stocked above Llewellyn Falls. The

populations in Corral Valley and Coyote Valley Creeks also became introgressed

sometime during the 1950's from an unknown source.

Efforts to restore pure populations of Paiute cutthroat trout above

Llewellyn Falls appear to have been successful following multiple chemical

treatments, combined with removal of hybridized trout using electrofishing. A 3-

year chemical treatment project conducted during 1991 through 1993 successfully

removed hybrid trout from Silver King Creek in Upper Fish Valley upstream from

Llewellyn Falls. The population of Paiute cutthroat trout in Fly Valley Creek has

remained isolated by a barrier falls. Hybridized trout have been removed from

Four Mile Canyon Creek by electrofishing and chemical treatment during 1991

through 1993. Corral Valley Creek was chemically treated during 1964, and

retreated during 1977 to remove hybridized trout. Electrofishing surveys

following the 1977 treatment eliminated surviving hybridized trout. The chemical

treatments of Coyote Valley Creek during 1964 and 1977 failed, however,

retreatment during 1987 and 1988 appears successful because no hybrid trout

have been observed during subsequent electrofishing surveys. These results have

been reconfirmed by allozyme and nuclear DNA analysis of tissue samples from

all populations (Israel et al. 2002).

In summary, available evidence suggests that the native range of the

Paiute cutthroat trout is limited to the reach of Silver King Creek between

Llewellyn Falls and a presumed historic barrier in Silver King Canyon, and all

accessible tributaries within this reach. This range constitutes about 14.7

kilometers (9.1 miles) of stream habitat. It is also possible that Paiute cutthroat

trout are native to Corral Valley and Coyote Valley Creeks, but that will probably

remain a matter of conjecture because there are no collection records available

from these streams to document their faunal composition before they were

influenced by man. For this reason, there is also a slight possibility that Connell's
16

account of the situation is incorrect and that the true native range of the Paiute

cutthroat trout is Silver King Creek above Llewellyn Falls. 

Following Snyder's discovery and description, the California Department

of Fish and Game made several attempts to transplant Paiute cutthroat trout into

other waters. The first documented introduction was made in 1937 into upper and

lower Leland Lakes. That transplant failed, but another effort was made in 1946

when they were introduced into the North Fork of Cottonwood Creek. Progeny of

that transplant survive to the present. A list of known transplant attempts is

shown in Table 1. The present distribution of Paiute cutthroat trout consists of a

population in Silver King Creek above Llewellyn Falls and tributary populations

in Fly Valley, Four Mile Canyon Creek, Coyote Valley, and Corral Valley Creeks

(Figure 2), and four self-sustaining, pure populations outside the native drainage

in the North Fork of Cottonwood and Cabin Creeks (Figure 3), and Stairway and

Sharktooth Creeks (Figure 4). The introduced population in Delaney Creek,

Yosemite National Park, Tuolumne County, introduced in 1968, is suspected to

be extirpated due to the presence of brook trout (Salvelinus fontinalis). The only

known self-sustaining lake population in Birchim Lake (Inyo National Forest,

Inyo County) was confirmed to be introgresssed with rainbow trout in 1984 (D.

Wong, California Department of Fish and Game, pers. comm. 2000). 

F. Abundance

1. Silver King Creek Drainage

Paiute cutthroat trout now occupy a minimum of 33.2 kilometers (20.6

miles) of stream habitat in five widely separated drainages. Populations in the

Silver King Creek drainage occupy about 18.6 kilometers (11.5 miles) of stream

habitat, including 12.9 kilometers (8 miles) of good quality habitat that supports

on average 1,020 adult fish (> 150 millimeters [6 inches]) in 6 stream populations. 

Paiute cutthroat trout occupy approximately 4.3 kilometers (2.7 miles) in Silver

King Creek above Llewellyn Falls. Results from the 2001 population survey in

Upper Fish Valley were within the range of its historical population abundance, 
17

Table 1. Recorded transplants of Paiute cutthroat trout.

Water Location Year Source Number Status

Lower and Upper Leland

Lakes (El Dorado Co., CA)

1937 Silver King Cr. 400 Disappeared by

1941.

North Fork of Cottonwood

Cr. (Mono Co., CA)

1946 Silver King Cr.

Coyote Valley Cr.

Corral Valley Cr.

125

249

27

Reproducing

population

established.

McGee Cr. (Mono Co., CA) 1956 North Fork of

Cottonwood Cr.

? Unsuccessful.

Bull Lake (Alpine Co., CA) 1957 Silver King Cr. 46 Unsuccessful. 

Birchim Lake (Inyo Co.,

CA)

1957 North Fork of

Cottonwood Cr.

70 Highly

Introgressed.

Delaney Cr.

(Tuolumne Co., CA)

1966 Four Mile Canyon Cr.

Fly Valley Cr.

40

3

Displaced by 

brook trout.

Sharktooth Lake (Fresno

Co., CA)

1968 North Fork of

Cottonwood Cr.

Delaney Cr.

23

6

Population 

established in

outflow

(Sharktooth

Creek).

Cabin Cr. (Mono Co., CA) 1968 North Fork of

Cottonwood Cr.

60 Small reproducing

population 

established.

Stairway Creek (Madera

Co., CA)

1972 Delaney Cr. 77 Reproducing

population

established.

Heenan Lake (Alpine Co..

CA)

1983 Coyote Valley Cr. 170 Unsuccessful. 
Figure 3. Refugial populations of Paiute cutthroat trout in North Fork Cottonwood Creek and Cabin 

Creek, Inyo National Forest, Mono County, California.

18
Figure 4. Refugial populations of Paiute cutthroat trout in the Sierra National Forest, in Stairway Creek, 

Madera County, and Sharktooth Creek, Fresno County, California.

19
20

suggesting that the population may still be expanding (Figure 5). A total of 217

adult trout were observed during the snorkel and electrofishing surveys in 2001. 

Based on population estimates that compare multiple-pass electrofished test

sections, the population could consist of as many as 424 adult fish, which is the

average number of adults for this 1,900-meter (1.2-mile) reach. Figures 4 through

8 show how variable these populations can be as well as how quickly Paiute

cutthroat trout rebound from chemical treatments and natural disturbance. 

Twenty population estimate surveys have been conducted on Four Mile

Canyon Creek. The first was in 1968, and they have been conducted nearly every

year since 1984. Figure 6 shows the results from those surveys. In 2000,

California Department of Fish and Game surveyed 250 meters (820 feet) of

stream and estimated 78 adult fish per kilometer (126 per mile), which is lower

than the average of 133 adult fish per kilometer (215 per mile). Adult numbers

have stayed relatively constant while juvenile numbers have fluctuated widely. 

Paiute cutthroat trout occupy approximately 3 kilometers (1.9 miles) of habitat in

Four Mile Canyon Creek.

Seven population estimate surveys have been conducted on Fly Valley

Creek. The first survey was in 1984 and the last was in 2000 (Figure 7). In 2000,

California Department of Fish and Game surveyed 150 meters (492 feet) of

stream and estimated 118 adult fish per kilometer (190 per mile), which is lower

than the average of 221 adult fish per kilometer (356 per mile). While juvenile

numbers have historically fluctuated, adult numbers have stayed relatively

constant. Paiute cutthroat trout occupy approximately 1.8 kilometers (1.1 miles)

of habitat in Fly Valley Creek.

Eight population estimate surveys have been conducted on Corral Valley

Creek. The first survey was in 1974 and the last was in 2000 (Figure 8). In 2000,

California Department of Fish and Game surveyed a 150-meter (492-foot) section

and estimated 59 adult fish per kilometer (95 per mile), which is lower than the

average of 148 adult fish per kilometer (238 per mile). It is unclear why the

population decreased in 2000, but this decrease is most likely due to natural

fluctuations in the population. Paiute cutthroat trout occupy approximately 3.6

kilometers (2.2 miles) of habitat in Corral Valley Creek. 
21

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Year

0

250

500

750

1000

1250

1500

1750

2000

Popu al t oi n Est mi a et

JUVPCT

ADULTPCT

1965 1970 1975 1980 1985 1990 1995 2000 2005

Year

0

100

200

300

400

500

600

Est mi a et d number of f si h / mi el

JUVPCT

ADULTPCT

Figure 5. Historical population estimates (1964 to 2001) from the Upper Fish

Valley reach of Silver King Creek. The white bars represent adult Paiute

cutthroat trout (over 150 millimeters [6 inches]) and the dark bars

represent juvenile Paiute cutthroat trout (under 150 millimeters [6

inches]). Upper Fish Valley was treated with rotenone in 1964, 1976,

and 1991 to 1993. The Silver King Creek drainage experienced heavy

runoff in 1982, 1986, and 1998. (W. Somer, California Department of

Fish and Game, unpubl. data).

Figure 6. Historical population estimates (1968 to 2000) from Four Mile Canyon

Creek in the Silver King Creek drainage. The white bars represent adult

Paiute cutthroat trout (over 150 millimeters [6 inches]) and the dark bars

represent juvenile Paiute cutthroat trout (under 150 millimeters [6

inches]). In 1968, 1973, and 1980 population estimates represent both

adult and juvenile fish. Four Mile Canyon Creek was treated with

rotenone from 1991 to 1993. The Silver King Creek drainage

experienced heavy runoff in 1982, 1986, and 1998. (W. Somer,

California Department of Fish and Game, unpubl. data).
22

1980 1985 1990 1995 2000 2005

Year

0

100

200

300

400

500

600

700

Est mi a et d number of f si h / mi el

JUVPCT

ADULTPCT

Figure 7. Historical population estimates (1984 to 2000) from Fly Valley Creek in

the Silver King Creek drainage. The white bars represent adult Paiute

cutthroat trout (over 150 millimeters [6 inches]) and the dark bars

represent juvenile Paiute cutthroat trout (under 150 millimeters)[6

inches]. Fly Valley Creek has never been treated with rotenone. The

Silver King Creek drainage experienced heavy runoff in 1982, 1986, and

1998. (W. Somer, California Department of Fish and Game, unpubl.

data).

1970 1975 1980 1985 1990 1995 2000 2005

Year

0

100

200

300

400

500

600

Est mi ated number of f si h / mi el

JUVPCT

ADULTPCT

Figure 8. Historical population estimates (1974 to 2000) from Corral Valley Creek in

the Silver King Creek drainage. The white bars represent adult Paiute

cutthroat trout (over 150 millimeters [6 inches]) and the dark bars represent

juvenile Paiute cutthroat trout (under 150 millimeters [6 inches]). Corral

Valley Creek was treated with rotenone in 1964 and 1977. The Silver King

Creek drainage experienced heavy runoff in 1982, 1986, and 1998. (W.

Somer, California Department of Fish and Game, unpubl. data).
23

Population estimates on Coyote Valley Creek were sporadically conducted

from 1964 to 2000 (Figure 9). Two separate 150-meter (492-foot) sections,

Upper Meadow and Lower Meadow, were surveyed. In 2000, California

Department of Fish and Game estimated 508 adult fish per kilometer (819 per

mile) for the Upper Meadow section, which is slightly lower than the average of

528 adult fish per kilometer (852 per mile). The Lower Meadow section had an

estimated 589 adult fish per kilometer (950 per mile), which is higher than the

average of 444 adult fish per kilometer (716 per mile). Paiute cutthroat trout

occupy approximately 4.9 kilometers (3 miles) of habitat in Coyote Valley Creek.

2. North Fork of Cottonwood Creek

Occupied habitat for Paiute cutthroat trout in the North Fork of

Cottonwood Creek is limited to the uppermost 5.5 kilometers (3.4 miles) of

stream above the Tres Plumas barrier. In 1946, 401 Paiute cutthroat trout from

the Silver King Creek drainage (Table 1) were stocked. A standard section of

stream, from Granite Meadow downstream to a standard point just above the Tres

Plumas barrier, has been surveyed visually since 1989 by the California

Department of Fish and Game (Figure 10). The exclusion of grazing since 1993

and spawning enhancement projects in 1995 and 1996, which created 51

spawning sites, appear to have increased Paiute cutthroat trout numbers (D.

Becker, unpubl. data).

3. Cabin Creek

Cabin Creek was originally stocked in 1968 with 60 individuals from the

North Fork of Cottonwood Creek. Occupied habitat for Paiute cutthroat trout in

Cabin Creek is approximately 2.4 kilometers (1.5 miles). Visual surveys were

conducted on Cabin Creek in 1995 and 2000 (D. Becker, California Department

of Fish and Game, unpubl. data). In 1995, 139 fish were observed and were

broken down into size classes. Thirty-eight fish were between 100 and 200

millimeters (4 and 8 inches). The remaining 101 fish were between 200 to 254

millimeters (8 to 10 inches). In 2000, 186 fish were observed. This survey did

not break down individual sizes, although multiple size classes were present. 
24

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Year

0

250

500

750

1000

1250

1500

1750

2000

Est mi ated number of fish / mi el

1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Year

0

250

500

750

1000

1250

1500

1750

2000

Est mi ated number of f si h / mi el

JUVPCT

ADULTPCT

A

Figure 9. Historical population estimates (1984 to 2000) from Coyote

Valley Creek in the Silver King Creek drainage. Figure A

represents the Upper Meadow section and figure B represents

the Lower Meadow section. The white bars represent adult

Paiute cutthroat trout (over 150 millimeters [6 inches]) and the

dark bars represent juvenile Paiute cutthroat trout (under 150

millimeters [6 inches]). Coyote Valley Creek was treated with

rotenone in 1964, 1977, and 1987 to1988. The Silver King

Creek drainage experienced heavy runoff in 1982, 1986, and

1998. (W. Somer, California Department of Fish and Game,

unpubl. data).

B
25

1985 1990 1995 2000 2005

Year

0

100

200

300

400

N

u

m

b

ers

Figure 10. Visual observations from the North Fork of Cottonwood

Creek, Inyo National Forest, since 1989. The numbers include

all size classes observed (D. Becker, California Department of

Fish and Game, unpubl. data).

4. Stairway Creek

The population in Stairway Creek occupies approximately 3.5 kilometers

(2 miles) of stream habitat. Strand and Eddinger (1999) provide a summary of

historic population estimates in Stairway Creek. In 1972, 77 individuals from

Delaney Creek were stocked into Stairway Creek. Population surveys in Stairway

Creek using electrofishing methods occurred in 1974 through 1977 and 1981. In

1974, surveys located 5 adults and in 1975, 12 individuals were located (6 adults

and 6 juveniles). Surveys conducted in 1976 and 1977 showed a large increase in

numbers found with 150 and 118 individuals respectively. In 1981, a more

thorough survey was conducted, which estimated the population at 36.6

individuals per 100 meters (590 per mile) (excluding young of year) with 76

percent of the population estimated as adults (greater than 127 millimeters [5

inches]). In 1996, the Sierra National Forest conducted visual observations of

Paiute cutthroat trout in each habitat by life stage on 2.5 kilometers (1.5 miles) of

stream. Strand and Eddinger (1999) reported seeing 22.7 individuals per 100
26

 meters (366 per mile) with an estimated 70 percent of the population being adults

(greater than 127 millimeters [5 inches]). Comparison of population estimates

between years is not statistically reliable since different methods were used and

different lengths of stream were surveyed. A rain on snow event that occurred in

1997 resulted in down-cutting of the stream channel, reduced habitat complexity,

and fewer fish during the 2000 survey (P. Strand, pers. comm 2002). However,

the fish that were observed appeared more robust. Because of past mortality rates

from electrofishing salmonids on the Sierra National Forest, fly rod depletion

(Stephens and Christenson 1980) was selected as a means to estimate the number

of fish per pool during the 2000 survey. Thirty pools were sampled with an

average of 4.3 individuals per pool (P. Strand, unpubl. data). The fly rod

depletion method is not intended to be statistically reliable and is biased towards

larger fish; however, it can be used to determine the minimum number of fish per

pool. 

5. Sharktooth Creek

Strand and Eddinger (1999) also provided a summary of historic

population estimates in Sharktooth Creek. In 1968, 29 individuals, 6 from

Delaney Creek and 23 from North Fork of Cottonwood Creek, were stocked into

Sharktooth Lake. In 1970, a 4-hour angling survey conducted in the lake resulted

in no fish taken. In 1973, visual surveys of the lake and outlet stream (Sharktooth

Creek) resulted in no observations. In 1975, personnel of the California

Department of Fish and Game noted several Paiute cutthroat trout in the outlet

stream. The next survey was conducted in 1999 by Sierra National Forest

personnel. Fish from Sharktooth Lake evidently moved downstream into

Sharktooth Creek and now occupy approximately 3.2 kilometers (2 miles) of

stream from the outlet of Sharktooth Lake to the confluence with Lost Keys Lake

outlet stream. Fly rod depletion and visual observation were selected as a means

to estimate the number of fish per pool (Stephens and Christenson 1980). 

Twenty-five pools were sampled in the only low gradient section of occupied

habitat. Fifty-eight individuals were caught or observed in the pools for an

average of 2.32 fish per pool. The fly rod depletion method is not intended to be

statistically reliable and is biased towards larger fish; however, it can be used to

determine the minimum number of fish per pool. 
27

G. Habitat Description

1. Silver King Creek Drainage

As part of the California Wilderness Act, 65,000 hectares (160,000 acres)

were set aside in 1984 as the Carson-Iceberg Wilderness. This area is managed

both by the Humboldt-Toiyabe and Stanislaus National Forests. The entire

portion of the Silver King Creek drainage occurs within the Humboldt-Toiyabe

National Forest. This description of habitat is based on the account presented by

Ryan and Nicola (1976).

Silver King Creek is a tributary of the East Fork Carson River, which

drains into the Lahontan Basin. The creek originates at 2,926 meters (9,600 feet)

elevation in the southernmost portion of the drainage, and flows north through

three distinct valleys for approximately 22.5 kilometers (14 miles) where it meets

the East Fork Carson River. Between the headwaters and the confluence of Silver

King Creek with the East Fork Carson River, eight tributaries, three above and

five below Llewellyn Falls, join Silver King Creek. Llewellyn Falls, at an

elevation of 2,438 meters (8,000 feet), is located at the head of Lower Fish

Valley, some 16.2 kilometers (10 miles) above the confluence with the East Fork

Carson River. The physical characteristics of Silver King Creek and its

tributaries are described in Table 2.

From its source, Silver King Creek flows precipitously for 3.2 kilometers

(2.0 miles) before beginning a gradual descent to Upper Fish Valley in an area of

washed-out beaver ponds just above the mouth of Fly Valley Creek. For 2.4

kilometers (1.5 miles), through Upper Fish Valley, it is a typical meandering

meadow creek, averaging 3.7 meters (12 feet) wide and 0.3 meter (1 foot) deep in

the summer. Several soda springs occur in the valley, with some seeping directly

into the stream. From the southeast, Four Mile Canyon Creek enters 2.0

kilometers (1.2 miles) above Llewellyn Falls, while Bull Canyon Creek joins the

mainstem from the west 0.8 kilometer (0.5 mile) above Llewellyn Falls. In 1984,

an abandoned stream channel was reconnected with the mainstem, providing 0.46

kilometers (0.3 miles) of spawning and juvenile rearing habitat. The upstream

portion of the channel begins approximately 0.2 kilometer (0.1 mile) below the
28

Table 2. Physical characteristics of Silver King Creek and its principal tributaries. Modified from 

and Nicola (1976). 1

Stream Length

(kilometers)

Occupied

habitat

(kilometers

Historic

habitat

(kilometers)

Drainage

area

(hectares)

Elevation 

(meters)

 max min

Ave

gra

 (per

Fly Valley 2 1.8 0 414.4 2,682 2,512 8Four MileCanyon

4.5 3.0 0 880.6 3,048 2,487 1

Bull Canyon 4 1.0 0 673.4 2,902 2,463 1Tamarack Lake 2 0 0.3 181.3 2,835 2,423 2Unnamedtributaries

2.3 0 0.9 51.8 2,877 2,414 2

Tamarack 4.8 0 3.4 932.4 2,804 2,365 9Coyote Valley 8 4.9 0.5 1,217.3 3,048 2,377 8Corral Valley 5.6 3.6 0 1,346.8 3,347 2,743 7Snodgrass 3.6 0 0 854.7 2,438 2,088 9Silver King(exclusive oftributaries)

22.5 4.3 9.6 5,335.4 2,865 1,951 4

Total 59.3 18.6 14.7 11,914

1 Distances, areas, and elevations measured from USGS topographic maps.
29

confluence of Silver King Creek and Four Mile Canyon Creek. The lower portion

of the channel rejoins the mainstem immediately above the confluence of Silver

King Creek and Bull Canyon Creek. 

At the lower end of Upper Fish Valley, the stream gradient increases

through a sparsely forested section before reaching Llewellyn Falls. The vertical

drop of Llewellyn Falls is approximately 6.1 meters (20 feet). Within the 2.8-

kilometer (1.7-mile) length of Lower Fish Valley, two small tributaries enter the

mainstem from the west: Tamarack Lake Creek, located 1.2 kilometers (0.7 mile)

below Llewellyn Falls, and a short, unnamed tributary downstream another 1.2

kilometers (0.7 mile). Long Valley, only 1.5 kilometers (0.9 mile) long, is the

shortest of the three valleys. No tributaries enter this section of Silver King

Creek. Between Lower Fish Valley and Long Valley the gradient increases, but

no barriers similar to Llewellyn Falls are known to exist in this section. Below

Long Valley, Tamarack Creek enters Silver King Creek from the west 0.6

kilometer (0.4 mile) below Long Valley, and Coyote Valley Creek enters from the

east 1 kilometer (0.6 mile) farther downstream.

Approximately 2.8 kilometers (1.7 miles) below the mouth of Coyote

Valley Creek, Silver King Creek descends through Silver King Canyon and

emerges from the canyon in the vicinity of Snodgrass Creek. Upstream from

Snodgrass Creek, in the canyon, a series of falls present a fish barrier to nonnative

trout and nonsalmonid native fish species that occur downstream. No tributary of

significance enters Silver King Creek from Snodgrass Creek downstream for 5.4

kilometers (3.4 miles) until its confluence with the East Fork Carson River. 

Three small lakes occur in the drainage: 1) Tamarack Lake, 2) Whitecliff Lake,

and 3) an unnamed lake in the headwaters of Four Mile Canyon Creek. The

average gradient of Silver King Creek is 4.1 percent, which is less than any of its

tributaries. However, the portion of Silver King Creek between Fly Valley and

Corral Valley Creeks, has an average gradient of 1.6 percent.

In 1984, 1987, and 1990, personnel from the California Department of

Fish and Game, U. S. Fish and Wildlife Service, and the U.S. Forest Service

along with volunteers from Trout Unlimited participated in interdisciplinary

functional assistance trips to the Silver King Creek drainage to conduct physical

habitat and biological field surveys (see Appendix A). The objectives of this
30

effort were to provide the National Forest with a general assessment of habitat

and to provide recommendations for future management. Habitat surveys were

performed using the General Aquatic Wildlife System procedures (Duff et al.

1989). A Habitat Condition Index is obtained using the General Aquatic Wildlife

System methodology which can then be used to provide habitat trend data. Nine

stations were monitored on Silver King Creek above Llewellyn Falls, two stations

on Bull Canyon Creek, one station on Fly Valley Creek, two stations on Four

Mile Canyon Creek, four stations on Coyote Valley Creek, and two stations on

Corral Valley Creek (Appendix A, Table A1 and Figures A1 and A2). The

Habitat Condition Index over this 6 year period improved in nearly all of the

stations monitored, which was primarily due to a change in grazing management

(Table 3). However, even though most stations increased their Habitat Condition

Index rating, 12 of the 21 stations still rated as fair to poor. No habitat monitoring

has been done since 1990, nor has any habitat monitoring been done throughout

the historic range of Paiute cutthroat trout from Llewellyn Falls downstream to

Silver King Canyon.

Sediment samples were taken using a hollow core sampler during the

functional assistance trips in 1984 and 1990. Five samples were taken in riffle

areas at each station to determine how much fine sediment (particle sizes less than

6.35 millimeters [0.2 inches]) was present. Excess fine sediment is known to

increase mortality of salmonid embryos (Chapman 1988; Bjornn and Reiser 1991)

and could be a limiting factor in recruitment. Duff (1991) recommended that the

minimum amount of fine sediment should not exceed 30 percent and that natural

fine sediment amounts in Silver King Creek fluctuated between 20 and 30

percent. Results from this sampling effort revealed that the amount of fine

sediment stayed constant between 1984 and 1990 (39.3 and 39.4 percent

respectively) (Table A2). No sediment sampling has been done since grazing was

stopped in 1994. The basin was logged in the 1860's, used as pasture for sheep in

the early 1900's through the late 1930's, and used as pasture for cattle from the

1940's through 1994 (Overton et al. 1993; P. Shanley, pers. comm. 2000). 
31

Table 3. Summary of Habitat Condition Index (HCI) ratings from 1984,

1987, and 1990. (Modified from Duff 1991).

Stream Station Channel

Type

HCI

1984

HCI

Rating

1984

HCI

1987

HCI

Rating

1987

HCI

1990

HCI

Rating

1990

Silver King S1:610 C3 51.5 Poor 54.9 Poor 58.6 Poor

Silver King S2:640 C3 65 Fair 55.3 Poor 84.2 Good

Silver King S3:641 C3 64.8 Fair 54.6 Poor 78.8 Good

Silver King S4:700 C3 38.5 Poor 37.9 Poor 68.4 Fair

Silver King S5:725 C3 28.8 Poor 35.4 Poor 65.9 Fair

Silver King S6:738 C3 48.3 Poor 54.6 Poor 69.7 Fair

Silver King S6A:745 C3 58.5 Poor 66.7 Fair 70.4 Fair

Silver King S7:775 B2/B3 63 Fair 63 Fair 69.7 Fair

Silver King S8:813 C3 41.7 Poor 46.9 Poor 51 Poor

Bull Canyon S1:040 C3 82.4 Good 83.7 Good 88.2 Excel.

Bull Canyon S2:100 B2 54.3 Poor 57.8 Poor 69.4 Fair

Fly Valley S1:500 B2/C2 84.4 Good 82.6 Good 83.4 Good

Four Mile S1:250 C3 53 Poor 63.3 Fair 76.3 Good

Four Mile S2:267 C3 --- --- 77.7 Good 77.7 Good

Coyote S1:400 C6 53 Poor 72 Good 75.2 Good

Coyote S2:467 C3 58 Poor 61 Fair 77.4 Good

Coyote S3:500 C6 40 Poor 68 Fair 69.1 Fair

Coyote S4:542 C3 54.5 Poor 56.4 Poor 67.1 Fair

Corral S1:571 C3 56 Poor 65.1 Fair 49 Poor

Corral S2:574 C3 46.5 Poor 60.2 Fair 57.5 Poor

HCI Scale by Stream Type

HCI Rating C3 C6 B2

Excellent > 85 > 80 > 85

Good 75-84.9 70-79.9 75-84.9

Fair 60-74.9 60-69.9 60-74.9

Poor < 60 < 60 < 60

Channel typesfollow Rosgen (1996): 

B: Moderate gradient, riffle-dominated stream.

C: Low gradient,, meandering, riffle-pool stream. 

Numbers denote streambed composition: boulders (2), cobble (3), or silt/clay (6)
32

Macroinvertebrate sampling also occurred during the functional assistance

trips in 1984, 1987, and 1990. Samples were collected at most of the General

Aquatic Wildlife System stations using a Winget-modified surber net. Three

types of indices were reported: (1) a diversity index (DAT), which combines a

measure of dominance and number of taxa (Table A3); (2) standing crop, which is

the community dry weight biomass per sample (Table A4); and (3) a biotic

condition index (BCI), which indicates, as a percentage, how close an aquatic

ecosystem is to its own potential (Table A5). No trends were observed during

these functional assistance trips, however, both the diversity and biotic condition

indices were rated good to excellent while the standing crop data ranged from

poor to excellent. 

In the late 1940's and early 1950's, beaver (Castor canadensis) were

introduced into Silver King Creek and the upper East Fork of the Carson River

drainages (Hensley 1946; Ingles 1965). By 1964, they had established active

colonies in lower and upper Four Mile Canyon Creek, and in Fly Valley at the

confluence of Fly Valley and Silver King Creeks. Beaver have since been

trapped out or have abandoned their colonies, so as of 2002, there are no active

beaver colonies in the drainage. 

In the nonmeadow portions of the watershed, Jeffrey pine (Pinus jeffreyi),

lodgepole pine (Pinus contorta), and red fir (Abies magnifica) are the dominant

conifers, while dense stands of aspen (Populus tremuloides) are common

throughout the drainage. Sagebrush (Artemisia tridentata) is common near the

outer periphery of the mainstem meadows. Six species of willow and sedges are

the dominant riparian species present in the Silver King Creek drainage (Table 4).

2. North Fork of Cottonwood Creek

The North Fork of Cottonwood Creek is a small, spring-fed brook that

originates on the east slope of Paiute Mountain, in the White Mountains of

east-central California. All occupied portions of the stream occur within the Inyo

National Forest in Mono County (Figure 3). The stream flows southeasterly for

approximately 7.2 kilometers (4.5 miles) before merging with the South Fork to
33

Table 4. Common and scientific names of the riparian plant communities in

the Silver King Creek drainage (Modified from Winward 1984).

Common Name Scientific Name

Geyer willow Salix geyeriana

Lemmons willow Salix lemmonii

Blueberry willow Salix boothii

Eastwoods willow Salix eastwoodiae

Sierra willow Salix orestera

Little willow Salix planifolia

Rocky Mountain sedge Carex scopulorum

Nebraska sedge Carex nebrascensis

Water sedge Carex aquatilis

Rusty sedge Carex subfusca

Winged sedge Carex microptera

Beaked sedge Carex rostrata

Kentucky bluegrass Poa pratensis

Tufted hairgrass Deschampsia caespitosa

Red fescue Festuca rubra

Western needlegrass Achnatherum occidentalis
34

form Cottonwood Creek, which then flows eastward into Fish Lake Valley,

Nevada. Only one major tributary, Tres Plumas Creek, enters the North Fork of

Cottonwood Creek approximately 1.6 kilometers (1.0 mile) above its mouth. 

From its headwaters at 3,096 meters (10,155 feet) to the mouth of Tres Plumas

Creek at 2,784 meters (9,141 feet), the North Fork of Cottonwood Creek descends

312 meters (1,023 feet) in 5.6 kilometers (3.5 miles) (Wong 1975). The average

gradient is 5.6 percent, greater than that of Silver King Creek (Ryan and Nicola

1976). Despite the high gradient, the streambed is composed predominantly of

fine sediments. The relatively stable, spring-fed flows, together with a low

frequency of flooding, are believed to be responsible for the high amount of fine

sediments (Wong 1975). Mean stream width is 2.3 meters (7.5 feet) with a 1:1

ratio of pools and riffles (Wong 1975). Pool depths range between 0.3 and 2.0

meters (1 and 7 feet) (Wong 1975). 

Wong (1975) described the stream in three sections. The upper section

flows through relatively flat stringer meadows with sections of heavy willow

(Salix sp.) growth. The second section flows through a narrow canyon that

increases the gradient, creating a series of cascades that form barrier falls 3 to 4

meters (10 to 13 feet) high. The stream is characterized by large boulders that

create plunge pools and it is heavily overgrown with a tree canopy of aspen and

understory of willow. The third section again flows through more meadows with

low gradient, and willow dominates as stream cover. A 2.3-meter (7-foot) barrier

is located 100 meters (330 feet) above the confluence with Tres Plumas Creek.

The climate of the Cottonwood Creek basin is cool and dry, as it is

throughout the higher elevations of the White Mountains (Ryan and Nicola 1976). 

Studies in 1973 by Wong (1975) and in 1974 by Diana (1975) determined that the

summer stream discharge ranges from 0.6 to 1.8 cubic feet per second, with daily

maximum water temperatures ranging from 12 to 15.8 degrees Celsius (53.6 to

60.4 degrees Fahrenheit). Despite the abundance of spring-fed water sources,

diurnal water temperatures varied as much as 10.5 degrees Celsius (18.9 degrees

Fahrenheit). Limber pine (Pinus flexilis), aspen, and mountain mahogany

(Cercocarpus ledifolius) are found in the drainage in addition to bristlecone pine

(Pinus longaeva), but on the whole, there are considerably fewer species of trees

than in the Silver King Creek drainage. 
35

As in Silver King Creek, beavers were introduced into the Cottonwood

Creek drainage. A colony became established in the North Fork of Cottonwood

Creek, primarily between the Granite Meadow tributary and the mouth of Tres

Plumas Creek (Ryan and Nicola 1976). Efforts to eliminate beaver from the

North Fork of Cottonwood Creek have been successful. Grazing has occurred

since the surrounding area was first settled. Originally, sheep were grazed, then

beginning in 1923 only cattle were grazed. However, grazing within the North

Fork Cottonwood drainage has been vacant and inactive since 2000.

3. Cabin Creek 

Cabin Creek is a high elevation stream (3,200 meters [10,500 feet])

located 16 kilometers (10 miles) north of Cottonwood Creek in the White

Mountains, Inyo National Forest, Mono County, California (Figure 3). Like

Cottonwood Creek, Cabin Creek is small, flowing most of the year at less than 1

cubic foot per second. It flows south into Leidy Creek, which then flows

eastward across the California-Nevada border into Fish Lake Valley. Dawne

Becker (unpubl. data) characterizes Cabin Creek as a high gradient stream with

many riffles, a few small pools, little spawning habitat, and poor winter habitat. 

The average gradient for the entire stream is 14.4 percent. The lower section of

stream, from the confluence with Leidy Creek to about 3,000 meters (9,840 feet)

elevation, has a gradient of 20.2 percent. The upper section of stream has an

average gradient of 9.2 percent. Most of the stream is heavily vegetated with

dense willows of all age classes with grasses, sedges (Carex sp.), and paintbrush

(Castilleja sp.). Upland vegetation includes sagebrush, lupine (Lupinus sp.), and

a few pine trees. Cabin Creek is within an active livestock grazing allotment. 

Some degradation of the riparian zone and stream is occurring from

overutilization. Sloughing banks and trampling of tributary spring channels are

causing increased sediment input.

4. Stairway Creek

Stairway Creek, Madera County, California, originates in two forks at

2,743 meters (9,000 feet) elevation and flows south into the Middle Fork San

Joaquin River. The creek is located within the Ansel Adams Wilderness Area on

the Sierra National Forest (Figure 4). Strand and Eddinger (1999) described
36

Stairway Creek based on a survey conducted in 1996. The survey focused on a

2.5-kilometer (1.6-mile) low gradient section of stream, just upstream of a 500-

meter (1,640-foot) long section of stream with a greater than 40 percent gradient,

above the confluence with the Middle Fork of the San Joaquin River. This

section serves as a natural barrier to fish from downstream. A combination of A2

(greater than 4 percent gradient, confined channel, boulder substrate) and B3 (1 to

4 percent gradient, moderately confined channel, boulder/cobble substrate)

Rosgen types (Rosgen 1996) describe this 2.5-kilometer (1.6-mile) reach. Using

U.S. Forest Service Region 5 habitat typing methods (U.S. Forest Service 1996),

6 percent of the stream length was characterized as fast water while 94 percent

was slow water. A breakdown of these data are summarized in Table 5. Channel

stability (Pfankuch 1975) was rated “good” for all reaches sampled. Canopy

cover was approximately 40 percent in the riparian zone, accounting for the low

quantity of large woody debris, 3.3 pieces per 100 meters (328 feet), found in the

stream.

A 650-meter (2,132-foot) Stream Condition Inventory (U.S. Forest

Service 1996) reach was established in 2000 by Sierra National Forest personnel

(P. Strand, unpubl. data), in order to monitor long-term habitat trends within

Stairway Creek. This Stream Condition Inventory reach was within the

2.5-kilometer (1.6-mile) reach originally surveyed in 1996, and consisted of 41

percent (linear length) slow water habitats and 59 percent fast water habitats. 

Other information collected is summarized in Tables 6 and 7. 

5. Sharktooth Creek

Sharktooth Creek exits Sharktooth Lake at 2,999 meters (9,836 feet). It is

a headwater tributary to Fish Creek that flows northwest into the Middle Fork San

Joaquin River, Fresno County, California. The creek is located within the John

Muir Wilderness Area in the Sierra National Forest (Figure 4). Sharktooth Creek 
37

Table 5. Summary of habitat surveys on Stairway Creek conducted in 1996. 

All habitats were reduced to pool, riffle, or run based on data

output from FISHHAB program (U.S. Forest Service R5 Version

2) (Strand and Eddinger 1999). See Rosgen (1996) for description

of stream type. 

Reach # Stream

Type

Length

(meters)

Percent

Pools

Percent

Riffles

Percent

Runs

1 A2 314 92 1 7

2 B3 269 32 11 57

3 A2a+ 257 70 30 0

4 B3 747 26 6 68

5 A2a+ 377 71 7 22

6 B2 121 31 0 69

7 A2 418 56 5 39

Mean 54 8 38

Table 6. Cross sectional data from 2000 survey of Stairway Creek (P.

Strand, U.S. Forest Service, unpubl. data).

Cross Section Gradient

(percent)

Entrenchment

(meters)

Width/Depth

Ratio

1 2.4 2.0 23.0

2 0.53 8.8 25.0

Mean 1.46 5.4 24.0
38

Table 7. Transect data from 2000 survey of Stairway Creek (P. Strand, U.S.

Forest Service, unpubl. data).

Transect

Number

Bankfull

Width

(meters)

Depth

(meters)

Width at

2X

Bankfull

Depth

(meters)

Width/Depth

Ratio

Entrenchment

(meters)

5 6.35 0.35 12.0 18 1.9

10 5.05 0.40 50.5 13 10.0

15 5.35 0.35 8.5 15 1.6

20 9.05 0.43 74.2 21 8.0

25 9.95 0.28 11.5 36 1.16

30 6.7 0.31 9.0 22 1.3

35 7.75 0.37 62.0 21 8.0

40 6.0 0.34 7.0 18 1.17

45 11.55 0.33 14.0 35 1.21

50 7.05 0.37 14.0 19 2.0

Mean 7.48 0.35 26.27 21.8 3.63
39

is described by Strand and Eddinger (1999) as having high gradient sections that

provide natural migration barriers. A 250-meter (820-foot) section of stream near

the confluence with Lost Keys Lake outflow is described as a cascade/falls that

has a gradient of 35 percent with large cobble and boulders as substrate. 

Upstream of this point a step-pool sequence develops as the gradient reduces to

less than 15 percent. Then comes a low gradient (less than 2 percent) section,

approximately 1,565 meters (5,133 feet) in length, that is described in greater

detail below. Above this section, the stream again increases in gradient to the

outflow of Sharktooth Lake.

A Stream Condition Inventory (U.S. Forest Service 1996) reach was

established in 1999 by Sierra National Forest personnel on the lower gradient

middle section (approximately 1,565 meters [5,133 feet]) of Sharktooth Creek

(Strand and Eddinger 1999), in order to monitor long-term habitat trends within

Sharktooth Creek. This section of stream was a Rosgen type C3 (less than 2

percent gradient, well developed floodplain, mostly cobble with lesser amounts of

gravel and sand, Table 8), and included 205 pieces of large woody debris with 7

aggregations, and stream shading was 71 percent, which indicates that the riparian

area is dominated by large woody species of trees. Sixty percent of the stream

length was characterized as fast water (riffles, cascades, and step-pools) while 40

percent was slow water (pools, glides and runs). Bank stability was 75 percent or

greater for all 50 transect points, which are considered good ratings (U.S. Forest

Service 1996). The mean temperature was 12 degrees Celsius (54 degrees

Fahrenheit) with a pH of 7 and a dissolved oxygen reading of 10.4 milligrams per

liter. These water quality data indicate that Sharktooth Creek does not have any

water quality deficiencies for Paiute cutthroat trout, which require cool, well

oxygenated water for all life stages. Table 8 shows cross section data while Table

9 provides transect data.
40

Table 8. Cross sectional data from 1999 survey of Sharktooth Creek (Strand

and Eddinger 1999).

Cross Section Gradient

(percent)

Entrenchment

(meters)

Width/Depth

Ratio

1 1.64 2.15 11.12

2 1.37 3.17 19.25

3 1.19 6.52 14.37

Mean 1.4 3.95 14.91

Table 9. Transect data from 1999 survey of Sharktooth Creek (Strand and

Eddinger 1999).

Transect

Number

Bankfull

Width

(meters)

Depth

(meters)

Width at 2X

Bankfull

Depth

(meters)

Width/Depth

Ratio

Entrenchment

(meters)

5 8.6 0.32 > 30 26.87 3.49

10 3.1 0.41 8.1 7.52 2.61

15 3.3 0.45 14.65 7.33 4.44

20 3.21 0.12 7.79 26.75 2.43

25 4.25 0.19 9.1 22.37 2.14

30 4.2 0.3 9.8 14 2.33

35 3.08 0.24 7.05 12.83 2.29

40 2.7 0.12 4.1 22.5 1.52

45 5.95 0.37 8.05 16.08 1.35

50 3.1 0.64 8.85 4.84 2.85

Mean 4.15 0.32 10.75 16.11 2.55
41

H. Reasons for Listing and Current Threats

Species are placed on the endangered species list based on one or more of

the five listing factors for Federal listing of a species in section 4(a)(1) of the

Endangered Species Act. The five listing factors are: (1) The present or

threatened destruction, modification, or curtailment of habitat or range; (2) 

Overutilization for commercial, recreational, scientific, or educational purposes;

(3) Disease or predation; (4) Inadequacy of existing regulatory mechanisms; and

(5) Other natural and manmade factors affecting the species’ continued existence. 

The Paiute cutthroat trout was originally listed as endangered under the

Endangered Species Preservation Act on March 11, 1967 (U.S. Fish and Wildlife

Service 1967), and was reclassified to threatened on July 16, 1975 to facilitate

management and allow regulated angling (U.S. Fish and Wildlife Service 1975). 

Threats at the time of reclassification included livestock grazing, recreational

development, and hybridization from rainbow trout introduction. Appendix B

delineates the relationships between threats, recovery actions that address them,

and recovery criteria. Existing threats are as follows:

(1) The present or threatened destruction, modification, or curtailment of habitat

or range.

Valuable cover for stream populations of cutthroat trout is provided by

undercut banks, which are dependent on extensive vegetative cover for their

stability (Behnke and Zarn 1976). Streambank sloughing occurs as the result of

normal erosive forces (floods, channel realignment, etc.) but can be accelerated

by human-caused activities (off-highway vehicle use, grazing, logging, etc.). 

Heavy recreation, such as use by anglers and backpackers, can also result in

streambank degradation. Streambank sloughing results in the loss of instream

cover, increased water temperatures, streambed sedimentation, elimination of

spawning habitat, and reduced food supplies, and can retard the growth of

willows and aspen along the stream bank (Armour et al. 1994; Bohn and

Buckhouse 1985; Duff 1977; Kauffman et al. 1983a, 1983b; Marlow and

Pogacnik 1985; and Meehan and Platts 1978). 

Cattle last grazed the Silver King Basin during the summer of 1994. On

March 31, 1995, all authorized grazing on the Silver King Allotment was placed
42

under administrative rest and the allotment is currently vacant. It will remain

vacant unless appealed and upheld under the administrative appeal process. The

Cottonwood Creek and Tres Plumas allotments in the North Fork of Cottonwood

Creek also have the potential to affect Paiute cutthroat trout habitat (Kondolf

1994). Grazing was suspended for both these allotments in 2000, and will be in

non-use status for at least 10 years in the Cottonwood Basin (D. Hubbs, U.S.

Forest Service, pers. comm. 2002). Cabin Creek is within an active grazing

allotment and some degradation of habitat is occurring due to bank failure and

increased sediment input. Grazing does not currently affect occupied habitat in

Stairway and Sharktooth Creeks due to the inaccessibility of the area to livestock

(P. Strand, pers. comm. 2003).

Beavers have been a past threat to Paiute cutthroat trout because they

degrade spawning substrates and water quality. Beavers were introduced to the

east slope of the Sierra Nevada (Hensley 1946; Ingles 1965). Willow and aspen

growth along Silver King Creek and its tributaries, and the North Fork of

Cottonwood Creek is not adequate to support a permanent beaver colony. When

beavers colonize an area, as they did in upper Silver King Creek, they remove the

aspen faster than it can be regenerated. Consequently after a short period, the

beavers are forced to move on to other areas in search of food. After the beavers

move out, the abandoned dams and lodges wash out, and the fine silt and sand

from the dams is eroded and deposited in the streambed. The collapse of old

beaver dams, and associated down-cutting in Four Mile Canyon Creek has caused

degradation of that stream habitat. This series of events led to a 10-fold decline in

the population (Ryan in litt. 1982).

(2) Overutilization for commercial, recreational, scientific, or educational

purposes. 

Paiute cutthroat trout are susceptible to unregulated angling. Connell

(letter in Ryan and Nicola 1976) reported that in 1890 he and a companion took

1,500 fish from Silver King Creek in only 3 days of fishing. He noted that

"...they fished only a very small part of the time" and that their angling success

was enhanced when his fishing companion " ...conceived the idea of putting two

hooks on his line and succeeded in bringing out two fish in the majority of his

casts”. From 1952 to 1965, Silver King Creek was open to angling to reduce the
43

number of hybrid fish and the population above Llewellyn Falls was severely

depleted. Angling has been closed in Silver King Creek above Llewellyn Falls

since 1965. In the early 1970's, the population above the Falls was again

significantly reduced following a brief period of unauthorized angling by military

personnel (Ryan and Nicola 1976). Currently, overutilization for commercial,

scientific, or educational purposes is not occurring.

(3) Disease or predation

There are several natural predators (water shrews [Sorex palustris],

dippers [Cinclus mexicanus], and trichopteron larvae) on Paiute cutthroat trout

eggs and fry, but few on adult fish. Predation does not seem to be a significant

threat at this time. 

Disease is apparently a significant cause of adult mortality in the North

Fork of Cottonwood Creek, particularly in the post-spawning period. Wong

(1975) observed extensive fungal infections on the dorsal and caudal fins of

several spawned-out fish in the North Fork of Cottonwood Creek. Many of these

fish were so weakened by spawning that they were unable to recover. Few Paiute

cutthroat trout apparently live beyond the age of 3 in a wild stream environment

(Wong 1975). This disease has not been observed outside of the North Fork of

Cottonwood Creek.

(4) Inadequacy of existing regulatory mechanisms.

Existing regulatory mechanisms appear to be adequate at this time. 

However, agency commitments to recovery actions may be limited due to

budgetary constraints.

(5) Other natural and manmade factors affecting the species’ continued existence.

In the early part of the twentieth century, Paiute cutthroat trout were

eliminated from their presumed historic habitat through hybridization with

introduced rainbow trout, golden trout, and Lahontan cutthroat trout. Stocking

records from 1930 to 1953 document the plantings of thousands of nonnative
44

salmonids within the Silver King Basin. Nonnative salmonids continue to occupy

all of the historic habitat of the Paiute cutthroat trout.

Effective fish barriers are needed to keep other trout from invading Paiute

cutthroat trout waters. Even with effective barriers, there is an ever-present risk

that other trout will be introduced above the barriers by humans. Due to the

proximity of nonnative fish below Llewellyn Falls, the threat of an unauthorized

introduction of fish from below this area will remain until nonnative fish are

removed and Paiute cutthroat trout are reestablished below the falls. This action

will isolate Paiute cutthroat trout within the Silver King Basin because the Silver

King Canyon contains several barriers that will prevent salmonids from migrating

upstream. The Silver King Canyon is also difficult to access, which should

discourage humans from moving other trout above the barriers into historical

Paiute cutthroat trout habitat. The pre-1973 contamination of a portion of the

North Fork of Cottonwood Creek population was apparently the result of an

unauthorized trout introduction. 

Paiute cutthroat trout have a distinctive evolutionary history that

complicates management efforts to recover this fish. Paiute cutthroat trout

evolved in isolation from other fish species, and accordingly faced substantially

different selection pressures than most other North American salmonids. As a

consequence, this subspecies has developed behavioral traits that render its

prospects for coexisting with potential competitors highly unlikely. In those

situations where other salmonids have invaded Paiute cutthroat trout habitats, the

Paiute cutthroat trout have eventually been displaced. When associated with

Lahontan cutthroat trout or rainbow trout, the Paiute cutthroat trout tend to lose

their distinctiveness through introgressive hybridization. When associated with

brook trout, Paiute cutthroat trout tend to be displaced by competition (Schroeter

1998).

The Paiute cutthroat trout faces several threats to its existence because of

its limited distribution and its susceptibility to displacement by other salmonids. 

Several events have occurred in the past to imperil its existence, including: 1) the

early introduction of rainbow trout and Lahontan cutthroat trout into the Silver

King Creek drainage and subsequent introgression, 2) the introduction of beavers

into the Silver King Creek drainage, 3) the occurrence of a flood in Silver King
45

Creek that may have eliminated a natural barrier and allowed nonnative salmonids

to enter the drainage, 4) the degradation of habitat caused by livestock grazing

and off-highway vehicle use in the North Fork of Cottonwood Creek, and (5)

excessive angling. Its extremely limited distribution makes it vulnerable to

extinction in the event of a large disturbance (Dunham et al. 2003; Miller et al.

2003). Dunham et al. (2003) reported that the degree to which fish are affected

by a disturbance, such as fire, is related to the quality of the habitat before the

disturbance, the quantity and distribution of habitat (habitat fragmentation), and

the habitat requirements of the species impacted by the disturbance. The Paiute

cutthroat trout population in Silver King Creek, once it becomes re-established

throughout its native range, will be less susceptible than the out-of-basin

populations due to the size of the drainage, the size of the population, and the

quality and distribution of habitat in which it evolved. 

I. Conservation Efforts

All Paiute cutthroat trout habitat is publicly owned. Silver King Creek

and its tributaries are situated within the Humboldt-Toiyabe National Forest, the

North Fork of Cottonwood Creek and Cabin Creek are located within the Inyo

National Forest, and Stairway and Sharktooth Creeks lie within the Sierra

National Forest. Silver King Creek and its tributaries are within the CarsonIceberg Wilderness, Stairway Creek is within the Ansel Adams Wilderness, and

Sharktooth Creek is within the John Muir Wilderness. The California Department

of Fish and Game, with cooperation from us and the Humboldt-Toiyabe National

Forest, has proposed activities intended to extend the range of Paiute cutthroat

trout in Silver King Creek downstream of Llewellyn Falls to the Silver King

Canyon during the fall of 2004.

Previous management efforts to protect and restore the Paiute cutthroat

trout have primarily involved: 1) mechanical and chemical treatments to remove

competing or introgressed fish, 2) transplants to restore fish populations in

fishless waters, 3) land exchanges to secure essential habitat, 4) fishing closures,

and 5) fish habitat restoration projects. 

Paiute cutthroat trout have been introduced into several lakes and streams

within and outside their native range (Table 1). Self-sustaining populations have
46

been established in Silver King Creek above Llewellyn Falls, Fly Valley Creek,

Corral Valley Creek, Coyote Valley Creek, and Four Mile Canyon Creek in the

Silver King Creek drainage. Self-sustaining populations have also been

established in the North Fork of Cottonwood Creek, Stairway Creek, Sharktooth

Creek, and Cabin Creek. The introduced population in Delaney Creek is

suspected to be extirpated due to the presence of brook trout; however, no recent

surveys have been conducted. The 1983 introduction of Paiute cutthroat trout

into Heenan Reservoir was made to establish a broodstock for artificial

propagation. This population no longer exists. 

Corral Valley and Coyote Valley Creeks were treated in 1964 and 1977

respectively, to remove nonnative and hybrid trout. Electrofishing efforts

eliminated surviving hybrid trout and genetic analysis indicates that Corral Valley

Creek now contains pure Paiute cutthroat trout (Israel et al. 2002). The single

year treatment failed in Coyote Valley Creek because fish that survived above the

treatment area repopulated downstream meadow reaches. Coyote Valley Creek

was retreated during 1987 and 1988. Both Corral and Coyote Valley Creeks were

restocked from Fly Valley Creek following treatments. Surveys and genetic

analysis following the most recent treatments have not detected the presence of

introgressed fish in either stream. 

Silver King Creek was restocked from Coyote Valley and Fly Valley

Creeks from 1994 through 1998, in various locations between the downstream

end of Upper Fish Valley, upstream to the confluence of Fly Valley Creek. 

Additionally, Paiute cutthroat trout likely dispersed downstream from Fly Valley

and Four Mile Canyon Creeks, which contributed to the population reestablishing. 

Annual snorkel surveys of Silver King Creek have revealed that substantial

recruitment and multiple age classes had developed in the Paiute cutthroat trout

population by 1997, and total numbers exceeded 400 fish during 1999. 

Beaver control and habitat restoration were accomplished during the early

to mid- 1980's in the Silver King Creek drainage above Llewellyn Falls and in the

North Fork of Cottonwood Creek. Beavers have been extirpated in the vicinity of

the confluence of Fly Valley Creek with Silver King Creek and also in Four Mile

Canyon Creek. Beaver dams were subsequently breached in both locations. 

Extensive stream habitat restoration work, including rerouting the stream channel,
47

was accomplished in Four Mile Canyon Creek. Beaver were noted in past years

to occur in Tamarack and Snodgrass Creeks. No recent beaver activity has been

observed in Tamarack or Snodgrass Creeks, however, the potential for

recolonization throughout the drainage remains a concern.

In 1971, the Humboldt-Toiyabe National Forest completed a land

exchange with the Sierra Pacific Power Company to secure management

protection for most of the upper Silver King Creek watershed. The California

Department of Fish and Game acquired 290 hectares (720 acres) in the vicinity of

Poison Flat during 1990 for protection of Lahontan cutthroat trout, which also

provides watershed protection for Silver King Creek. In 1963, the U.S. Marine

Corps agreed to discontinue use of the watershed for survival training. In 1984,

the Toiyabe National Forest and the California Department of Fish and Game

rerouted lower Fly Valley Creek back into a historic channel to reduce

sedimentation from a large headcut that was moving through a series of old

beaver dams. Four Mile Canyon Creek was similarly rerouted from old beaver

dams, and various habitat projects were performed to stabilize the streambanks

and provide fish habitat during 1988 and 1989. Fish habitat improvement

structures and bank protection projects were constructed in Silver King Creek

during 1988. Cattle exclosure electric fences were constructed and maintained

during 1985 through 1994 in both Silver King and Coyote Valley Creeks. These

fenced exclosure areas protected stream reaches from grazing, and provided

reference stream reaches to evaluate grazing impacts in the unfenced reaches.

Paiute cutthroat trout are managed by the State of California under the

4(d) rule published in 1975, which states that Paiute cutthroat trout can be taken

in accordance with applicable State law and that violation of State law will also

be a violation of the Endangered Species Act (Code of Federal Regulations Title

50, Section 17.44). Silver King Creek and its tributaries above Llewellyn Falls

are closed to angling. Angling closures have also been established to protect the

populations in Coyote Valley Creek, Corral Valley Creek, and the North Fork of

Cottonwood Creek. Stairway Creek, Cabin Creek, and Sharktooth Creek are all

relatively inaccessible and lightly used, and therefore are managed as wild trout

fisheries without special protective regulations. The California Department of

Fish and Game and the U.S. Forest Service have periodically maintained a stream

guard in upper Silver King Creek to enforce the angling closure above Llewellyn
48

Falls. The Inyo National Forest prepared a habitat management plan for Paiute

cutthroat trout in 1991. That plan includes several projects to improve habitat

quality in the Cottonwood Creek basin. The actions proposed in the habitat

management plan are compatible with the objectives of this recovery plan.
49

II. RECOVERY 

A. Objective and Criteria 

The objective of this recovery plan is to recovery the Paiute cutthroat trout

by improving its status and habitat and eliminating nonnative salmonids so it can

be delisted. Criteria for accomplishing the goal of delisting are:

1. All nonnative salmonids are removed from Silver King Creek and its

tributaries downstream of Llewellyn Falls to fish barriers in Silver King

Canyon;

2. A viable population occupies all historic habitat in Silver King Creek and

its tributaries downstream of Llewellyn Falls to fish barriers in Silver

King Canyon; 

3. Paiute cutthroat trout habitat is maintained in all occupied streams; 

4. The refuge populations in Corral and Coyote Creeks, Silver King Creek,

and tributaries above Llewellyn Falls as well as out-of-basin populations

are maintained as refugia and are secured from the introduction of other

salmonid species; and

5. A long-term conservation plan and conservation agreement are developed,

which will be the guiding management documents once Paiute cutthroat

trout are delisted. 

Specifications for these recovery criteria are discussed in greater detail

below (section II.B).

Because this recovery plan is partially focused on habitat improvements, it

also provides conservation benefits for two candidate species, the Sierra Nevada

population of the mountain yellow-legged frog and the Yosemite toad. 
50

B. Recovery Strategy 

The primary threat to the Paiute cutthroat trout is hybridization with

nonnative trout, compounded by its extremely limited distribution (making it

vulnerable to catastrophic events). Consequently, it is critical to remove

nonnative trout from the historic range downstream of Llewellyn Falls and

reestablish Paiute cutthroat trout populations there, monitoring population

abundance and genetics to evaluate success. Reinvasion of Paiute cutthroat trout

habitat by nonnative trout should be prevented by monitoring or establishing

instream barriers and discouraging deliberate introductions. Because the Paiute

cutthroat trout is vulnerable to angling pressure, appropriate fishing regulations

and closures should be maintained and enforced by a stream guard and signage. 

Potential habitat degradation should be addressed by appropriate fish habitat

improvement actions, including management of recreational access and grazing,

and control of beaver populations as necessary. The recovery criteria above

should be met by addressing these threats, as detailed below. 

Meeting the first and second recovery criteria will secure long-term

protection and population viability of Paiute cutthroat trout by their expansion

within their native range. This range expansion will be accomplished by

removing nonnative trout from the Silver King Creek drainage from Llewellyn

Falls downstream to the Silver King Canyon, including tributaries, followed by

reintroduction with Paiute cutthroat trout from donor tributaries best suited as

determined by genetic testing (Israel et al. 2002). A viable population will be

achieved when the population is secure and comprises three or more age classes

for 5 years, and consists of a minimum of 2,500 fish greater than 75 millimeters

(3 inches) (Hilderbrand and Kershner 2000). This figure is a preliminary estimate

and may need to be revised as additional information becomes available. 

Population estimates will be made during the non-native fish eradication. This

estimate will be used as a surrogate to help us understand the population size of

Paiute cutthroat trout that will be expected within the historic range and aid in

validating the minimum number needed for recovery. Once this estimate is made,

population data from above Llewellyn Falls will be used to estimate a range in the

population size that can be expected due to inherent natural fluctuation as seen in

Figure 5.
51

The third recovery criterion is to maintain suitable habitat for Paiute

cutthroat trout. Historic and occupied Paiute cutthroat trout stream and riparian

habitat should have no degradation from existing conditions due to anthropogenic

effects. The condition of existing habitat will be identified using established

stream habitat monitoring protocols which use measurable and repeatable

methods (see section I.G above and Appendix A). Beaver control will need to be

conducted in the event that they repopulate the drainage. To secure the protection

of the North Fork Cottonwood population, a second barrier will be needed to

protect the population from the introduction of nonnative trout species from

downstream. Cabin Creek is within an active grazing allotment where continued

management will be necessary to ensure degradation of Paiute cutthroat habitat

does not occur. Stairway and Sharktooth Creeks are subject to limited human

disturbance since they are in designated wilderness areas, are inaccessible to

livestock, and get limited recreational use. Therefore, habitat monitoring should

be done periodically to document stochastic events such as a rain on snow event

which occurred in 1997 (P. Strand, pers. comm. 2002). 

The fourth recovery criterion is to protect and enhance Paiute cutthroat

trout that do not occupy historic habitat. To protect against a catastrophic event

that could affect the entire Silver King Creek gene pool, populations in Corral

Valley and Coyote Valley Creeks, Silver King Creek and tributaries (Four Mile

Canyon, Fly Valley, and Bull Canyon Creeks) above Llewellyn Falls, and the four

out-of-basin populations must be maintained as Paiute cutthroat trout refugia. 

Monitoring these populations will aid in management decisions aimed to maintain

and improve the abundance of Paiute cutthroat trout and collection of long-term

trend data. Continued genetic monitoring of all populations of Paiute cutthroat

trout will be used to: 1) monitor population genetic diversity, 2) evaluate

effective population size and reproductive isolation, 3) examine populations for

evidence of hybridization, and 4) identify appropriate donor sources.

The fifth and final criterion is to develop a long-term conservation plan

and conservation agreement that will guide the agencies responsible for the

management of Paiute cutthroat trout after it is delisted. The purpose of the

conservation plan is to ensure that adequate regulatory mechanisms and

management programs remain in existence after delisting to ensure that all

populations of Paiute cutthroat trout and their habitat are maintained. The
52

conservation plan will be consistent with other existing cutthroat trout subspecies

conservation plans. The purpose of the conservation agreement is to define the

role of the management agencies and to document their commitment to

implementing the conservation plan. The conservation plan and conservation

agreement will need to be approved and signed by all responsible agencies before

delisting occurs.

Prior to implementation of any task in this plan, the lead Federal agency

must comply with all applicable provisions of the National Environmental Policy

Act and the Endangered Species Act. All necessary Federal, State, and local

permits or authorizations must be obtained. These recovery criteria were

designed to provide a basis for consideration of delisting, but not for automatic

delisting. Before delisting occurs, we must determine that the five listing factors

(as discussed previously) no longer are present or continue to adversely affect the

listed species. The final decision regarding delisting will be made only after a

thorough review of all relevant information. It is our goal to achieve recovery as

quickly as possible while minimizing social and economic impacts.

C. Narrative Outline of Recovery Actions

1. Remove nonnative fish from Silver King Creek downstream from

Llewellyn Falls to barriers in Silver King Canyon. Hybridization, which

has occurred within and outside the native drainage, continues to be a

threat. Chemically treat Silver King Creek to remove all introgressed fish

downstream from Llewellyn Falls to barriers in Silver King Canyon,

including all tributaries that enter the mainstem in this reach. In addition,

Tamarack Lake, which was formerly stocked with trout in 1991, must be

treated to remove any remaining fish. Tamarack Lake will remain fishless

for the benefit of amphibian species.

2. Reintroduce Paiute cutthroat trout into renovated stream reaches in

historic habitat. The most effective means of insuring that the Silver King

population remains above critical minimum levels is by expanding the

population downstream into historical habitat. Franklin (1980)

recommended an effective population size of at least 500 individuals to

maintain adequate long-term genetic variation. Hilderbrand and Kershner
53

(2000) suggested that 2,500 individuals may be necessary to maintain

cutthroat populations in small streams. This estimate is preliminary and

may need to be revised as additional information becomes available.

Restock Silver King Creek below Llewellyn Falls with pure Paiute

cutthroat trout within 1 year after the final chemical treatment. 

Restocking may need to be continued for several years to enhance

recolonization. The fish used for restocking should be taken from

populations based on results from genetic analysis and will be mixed with

other populations, as necessary, to promote genetic heterozygosity (Israel

et al. 2002). Expansion of Paiute cutthroat trout downstream from

Llewellyn Falls will provide additional protection from the potential

unauthorized introduction of non-native trout.

3. Protect and enhance all occupied Paiute cutthroat trout habitat. Habitats

have been improved through livestock grazing closures and eradication of

beavers. Historic and occupied Paiute cutthroat trout stream and riparian

habitat should have no degradation from existing conditions due to

anthropogenic effects. Existing habitat will be identified using established

stream and riparian habitat monitoring protocols which use measurable and

repeatable methods. Ongoing monitoring will be necessary to detect

recolonization of beaver within Paiute cutthroat trout habitats. In addition,

various types of habitat protection and restoration measures are needed to

maintain populations at levels that are high enough to avoid the adverse

effects associated with inbreeding depression. Several actions are needed

to maintain or restore habitat conditions to the levels needed to support

recovery.

3.1 Restore and maintain riparian habitat quality and stream channels

in the Silver King Creek drainage. Recreation, livestock, and

beaver have degraded habitat conditions in the Silver King basin. 

Paiute cutthroat trout evolved in an isolated headwater

environment. They require good water quality and clean spawning

gravel to survive. The most favorable habitat is provided by

streams with undercut or overhanging banks and abundant riparian
54

vegetation. Several management activities are needed to improve

Silver King basin streams.

3.1.1 Institute a habitat monitoring program. Institute a stream

and riparian habitat monitoring program which uses an

established stream monitoring protocol with measurable

and repeatable methods.

3.1.2 Monitor and manage the amount of recreational trail and

campsite use adjacent to occupied habitats. Bank

conditions must be monitored and managed to prevent

physical damage to banks and associated riparian

vegetation. Trails and campsites should be relocated away

from streams in areas where stream-side degradation is

occurring.

3.1.3 Protect Paiute cutthroat trout habitat from effects of

grazing. Continue to exclude grazing in Silver King Creek

drainage.

3.1.4 Conduct periodic surveys to detect reinvasion by beavers. 

Periodic surveys should be made to detect beavers that

migrate to the Silver King Creek drainage from other areas

before they construct dams that create barriers to fish

migration and become sources of future streambed

sedimentation.

3.1.5 Remove beavers from the watershed and dismantle dams

and lodges if any are built. Beavers can severely degrade

areas, such as Silver King Creek, that do not have adequate

aspen or willow growth. Whenever they are discovered in

the Silver King Creek drainage, they should be removed

and the dams and lodges that have been built should be

dismantled.
55

3.1.6 Develop and implement solutions for other identified

habitat problems. If conflicting land uses are identified and

problems develop, solutions to the problems should be

developed and remedies implemented to provide habitat

recovery.

3.2 Restore and maintain stream banks, riparian vegetation, and stream

channels in the North Fork of Cottonwood Creek drainage. 

Habitat conditions in the North Fork of Cottonwood Creek

drainage are generally good, but localized damage has occurred in

some areas as the result of beaver use and past human activities.

Management activities will be required to maintain and/or improve

habitat in portions of the North Fork of Cottonwood Creek. 

Stream reaches that support Paiute cutthroat trout should be

periodically monitored to maintain existing habitat conditions

using an established stream monitoring protocol with measurable

and repeatable methods.

3.2.1 Conduct periodic habitat surveys. Conduct habitat surveys

to determine if there are any potential sources of habitat

degradation, including but not limited to stream

sedimentation, stream bank stability, or riparian conditions.

3.2.2 Continue to enforce road closure barriers at existing and

potential access points. Off-highway vehicles pose a threat

to Paiute cutthroat trout by directly degrading habitat when

crossing streams and creating new sources of erosion, and

providing anglers with easier access to Paiute cutthroat

trout streams. Existing road closures should be strictly

enforced and new barriers constructed if they are needed to

restrict access. If pioneer roads are created within the basin

area that would allow access to Cottonwood Basin,

establish barriers to eliminate unauthorized use. 
56

3.2.3 Protect Paiute cutthroat trout habitat from effects of

grazing. Continue to limit grazing in the North Fork

Cottonwood drainage. If grazing is allowed, cattle should

be excluded from all riparian areas and appropriate grazing

strategies implemented.

3.2.4 Maintain recreation opportunities as primitive and semiprimitive. Directing large numbers of recreational users to

North Fork of Cottonwood Creek would inevitably

stimulate unauthorized angling for Paiute cutthroat trout. 

Because Paiute cutthroat trout are currently present in very

low numbers and are extremely vulnerable to angling,

recreational access to the basin should be maintained at

appropriate levels.

3.2.5 Conduct periodic surveys to detect reinvasion by beavers. 

Periodic surveys should be made to detect beavers that

migrate back to North Fork Cottonwood Creek from other

areas so they can be removed before they construct dams

that create barriers to fish migration and become sources of

future streambed sedimentation.

3.2.6 Remove beavers from the watershed and dismantle dams

and lodges. Whenever beavers are discovered in North

Fork Cottonwood Creek, they should be removed and the

dams and lodges they have built should be dismantled.

3.2.7 Construct a second barrier on North Fork Cottonwood

Creek. The existing pure population in the North Fork of

Cottonwood Creek is now restricted to the upper 5.5

kilometers (3.4 miles) above a natural barrier. A second

barrier is necessary to secure the population from

reinvasion of nonnative trout species.

3.2.8 Develop and implement solutions for other identified

habitat problems. If conflicting land uses are identified and
57

problems develop, solutions to the problems should be

developed and remedies implemented to provide habitat

recovery.

3.3 Maintain stream and riparian habitat quality in Stairway,

Sharktooth, and Cabin Creeks. Habitat conditions in the Stairway

and Sharktooth Creek drainages are generally very good, and

future management needs will be limited to maintaining existing

conditions. Cabin Creek is within an active grazing allotment

where continued management will be necessary to ensure

degradation of Paiute cutthroat trout habitat does not occur.

Stream reaches that support Paiute cutthroat trout should be

periodically monitored to maintain existing habitat conditions

using an established stream monitoring protocol with measurable

and repeatable methods.

3.3.1 Conduct periodic habitat surveys. Conduct habitat surveys

of each stream to determine if there are any potential

sources of habitat degradation, including but not limited to

stream sedimentation, stream bank stability, or riparian

conditions.

3.3.2 Protect Paiute cutthroat trout habitat from effects of grazing

in Cabin Creek. Implement a grazing strategy that will

protect occupied habitat from the effects of grazing in the

Cabin Creek drainage. 

3.3.3 Develop and implement solutions for other identified

habitat problems. If conflicting land uses are identified and

problems develop, solutions to the problems should be

developed and remedies implemented to provide habitat

recovery.

4. Continue to monitor and manage existing and reintroduced populations.

The number of fish in the existing populations must be stable or
58

increasing. Monitoring of Paiute cutthroat trout populations should track

population abundance and composition, identify any hybridization, assess

barrier integrity, and maintain genetic heterozygosity. 

4.1 Enforce all laws and regulations protecting the Paiute cutthroat

trout and its habitat, and periodically review their effectiveness. 

All laws and regulations that provide protection for Paiute

cutthroat trout must be enforced. Enforcement personnel from all

agencies should be given maps denoting the location of all

populations within their area of responsibility. These personnel

should also be advised of the types of activities most likely to be

detrimental to the Paiute cutthroat trout.

4.1.1 Maintain a seasonal guard in upper Silver King Creek.

Because of the extreme susceptibility of Paiute cutthroat

trout to angling pressure, a seasonal guard should be hired

to insure that the angling regulations above Llewellyn

Falls in Silver King Creek are properly enforced. 

4.1.2 Prevent exotic fish introductions into Paiute cutthroat trout

waters. Paiute cutthroat trout have been displaced from

several streams and lakes because of unauthorized

introductions of nonnative trout. This threat will always

exist, but several actions can be taken to minimize the risk. 

Packers and recreational users should be informed and

educated on the distinctiveness of the Paiute cutthroat trout

and advised of the consequences an unauthorized transplant

would have on existing populations and on their

opportunities to use the affected streams in the future. 

4.2 Review existing laws and regulations and propose necessary

changes. The Paiute cutthroat trout is unwary and therefore,

highly vulnerable to angling. Consequently, restrictive regulations

are necessary to maintain viable populations. The opportunity for

a highly regulated and special designation fishery above Llewellyn

Falls should be explored during the non-native fish eradication
59

described under Recovery Action 1. No fishing should be allowed

in the North Fork of Cottonwood Creek. Explore additional outof-basin population locations.

4.3 Maintain viable, genetically pure populations in Silver King Creek.

A variety of actions are needed to maintain the genetic integrity of

the existing populations in Silver King Creek. Baseline and

follow-up surveys are needed to ensure population levels are stable

or increasing and that other trout species have not invaded Paiute

cutthroat trout waters.

4.3.1 Monitor abundance and age class composition. 

Annually survey test sections to assess population size,

determine age class composition, and monitor the condition

of the different populations within the Silver King Creek

drainage.

4.3.2 Evaluate the potential for occurrence of hybrid trout.

Conduct annual surveys until population levels reach or

exceed recovery plan objectives. Subsequent surveys

should be conducted periodically to identify unauthorized

introductions of other trout species. Surveys should

include appropriate genetic analysis to detect hybrid

individuals. If hybrids are discovered, appropriate action

should take place.

4.3.3 Assess integrity of barriers. Periodically inspect all fish

barriers in the Silver King Creek drainage to ascertain their

effectiveness in preventing other fish species from invading

Paiute cutthroat trout habitats.

4.3.4 Mix populations in the Silver King drainage as necessary to

maintain genetic diversity. If it is determined that any of

the populations in the Silver King drainage suffer from

inbreeding depression or the long-term depletion of genetic
60

variance, they may be mixed with other populations to

promote genetic heterozygosity.

4.3.5 Develop and implement actions, as needed, to protect

genetic integrity. Take action and develop solutions to

protect the genetic integrity of these populations if threats

are identified.

4.4 Maintain viable, genetically pure populations in the North Fork of

Cottonwood Creek. The North Fork of Cottonwood Creek is a

necessary refuge for Paiute cutthroat trout in the event of a

catastrophic occurrence in the Silver King Creek drainage. It is

also important because it will help secure the genetic diversity of

other Paiute cutthroat populations. A variety of actions are needed

to maintain the genetic integrity of the existing population.

Baseline and follow-up surveys are needed to ascertain if

population levels are stable or increasing, critical fish barriers are

intact, and to ensure that other trout species have not invaded

Paiute cutthroat trout waters.

4.4.1 Monitor abundance and age class composition. 

Periodically survey test sections to assess population size,

determine age class composition, and monitor the condition

of the different populations.

4.4.2 Evaluate the potential for occurrence of hybrid trout.

Conduct periodic surveys to look for unauthorized

introductions of other trout species. Surveys should

include appropriate genetic analysis to detect hybrid

individuals. If hybrids are discovered, appropriate action

should take place.

4.4.3 Assess integrity of barriers. Periodically inspect all fish

barriers in the drainage to ascertain their effectiveness in

preventing other fish species from invading Paiute cutthroat

trout habitats.
61

4.4.4 Mix populations in North Fork Cottonwood Creek as

necessary to maintain genetic diversity. If it is determined

that the population in North Fork Cottonwood Creek

suffers from inbreeding depression or the long-term

depletion of genetic variance, they may be mixed with

other populations to promote genetic heterozygosity.

4.4.5 Develop and implement actions, as needed, to protect

genetic integrity. Take action and develop solutions to

protect the genetic integrity of this population if threats are

identified.

4.5 Maintain viable, genetically pure populations in Stairway,

Sharktooth and Cabin Creek drainages. The remote locations of

Stairway, Sharktooth and Cabin Creeks make them excellent

refuge habitats for the Paiute cutthroat trout. Maintaining the

existing population should require only modest management

efforts because of their remote locations.

4.5.1 Monitor abundance and age class composition. 

Periodically survey test sections to assess population size,

determine age class composition, and monitor the condition

of the different populations.

4.5.2 Evaluate the potential for occurrence of hybrid trout.

Conduct periodic surveys to look for unauthorized

introductions of other trout species. Surveys should

include appropriate genetic analysis to detect hybrid

individuals. If hybrids are discovered, appropriate action

should take place.

4.5.3 Assess integrity of barriers. Periodically inspect fish

barriers in each stream to ascertain their effectiveness in

preventing other fish species from invading Paiute cutthroat

trout habitats.
62

4.5.4 Mix populations in Stairway, Sharktooth, and Cabin

Creeks as necessary to maintain genetic diversity. If it is

determined that any of the populations in Stairway,

Sharktooth, or Cabin Creeks suffer from inbreeding

depression or the long-term depletion of genetic variance,

they may be mixed with other populations to promote

genetic heterozygosity.

4.5.5 Develop and implement actions, as needed, to protect

genetic integrity. Take action and develop solutions to

protect the genetic integrity of these populations if threats

are identified.

4.6 Explore additional out-of-basin locations. Because Paiute

cutthroat trout have a very limited range and refuge populations

are in isolated drainages susceptible to stochastic and

anthropogenic disturbances, it may be useful to increase the

number of refuge populations.

5. Develop a long-term conservation plan and conservation agreement. A

conservation plan for the long-term management of Paiute cutthroat trout

and a conservation agreement between all involved agencies must be

developed before the species can be delisted. The purpose of the

conservation plan is to ensure that adequate regulatory mechanisms and

management programs remain in existence after delisting to ensure that all

populations of Paiute cutthroat trout and their habitat are maintained. The

purpose of the conservation agreement is to define the role of the

management agencies and to document their commitment to implementing

the conservation plan.

5.1 Develop a long-term conservation plan. A conservation plan

should be prepared that will incorporate all the information

obtained through the completion of the recovery plan actions. All

agencies will need to maintain records on their recovery activities

and provide pertinent information in development of the

conservation plan. The conservation plan will need to provide
63

pertinent biological and management information on the Paiute

cutthroat trout for use in maintaining Paiute cutthroat trout

populations. It must identify how populations will be monitored to

document the status and condition of populations and habitats, and

will identify conditions that would warrant relisting the Paiute

cutthroat trout. The conservation plan should be developed and

approved through the conservation agreement by all agencies with

management jurisdiction over Paiute cutthroat trout populations

before the species is delisted. 

5.2 Develop a conservation agreement. A conservation agreement

should be approved and signed by all involved agencies with

Paiute cutthroat trout populations on areas under their jurisdiction

to document their approval and commitment to implementing the

conservation plan.

6. Inform the public of Paiute cutthroat trout recovery objectives and pertinent

management activities. Existing and prospective public users of the areas

that support Paiute cutthroat trout populations should be informed about the

Paiute cutthroat trout recovery effort, and should be notified of activities,

such as chemical treatments, that may temporarily restrict their use of an

area. Packers and other recreational users should be informed of the

consequences that unauthorized angling or "coffee-can" transplants will

have on the integrity of pure populations and on future recreational

opportunities.

6.1 Manufacture and post informational signs. Informational signs

should be installed at public access areas, and interested

individuals and organizations should be notified of management

activities that might affect their use of an area. 

6.2 Notify user groups of restoration goals, chemical treatments, and

future management. User groups should be notified of chemical

treatment schedules and advised to use alternative recreational

areas. Details of transplants should be made public by inclusion in

California Department of Fish and Game archives and publication
64

in California Fish and Game if deemed appropriate by the editors.

User groups should also be informed regarding the long-term

restoration goal of expanding Paiute cutthroat trout downstream to

Silver King Canyon, as well as the opportunity for California

Department of Fish and Game to establish a recreational fishery.
65

III. IMPLEMENTATION SCHEDULE 

The implementation schedule that follows lists the actions and estimated

costs for the recovery program for the Paiute cutthroat trout. It is a guide for

meeting the recovery goals outlined in this plan. Parties with authority,

responsibility, or expressed interest to implement a specific recovery action are

identified in the Implementation Schedule. The listing of a party in the

Implementation Schedule does not require, nor imply a requirement, that the

identified party has agreed to implement the actions or to secure funding for the

implementing the actions. However, parties willing to participate may benefit by

being able to show in their own budgets that their funding request is for a

recovery action identified in an approved recovery plan and is therefore

considered a necessary action for the overall coordinated effort to recover Paiute

cutthroat trout. Also, section 7(a)(1) of the Endangered Species Act directs all

Federal agencies to utilize their authorities in furtherance of the purposes of the

Endangered Species Act by carrying out programs for the conservation of

threatened and endangered species.

In the implementation schedule, actions are arranged in priority order. 

The assigned priorities are defined as follows:

Priority 1 - An action that must be undertaken to prevent extinction or

to prevent the species from declining irreversibly in the foreseeable

future. 

Priority 2 - An action that must be taken to prevent a significant

decline in population or habitat quality, or some other significant negative

impact short of extinction.

Priority 3 - All other actions necessary to meet the recovery objective.
66

Key to Acronyms used in the Implementation Schedule:

Agencies

CDFG = California Department of Fish and Game

FS = U.S. Forest Service

FWS = U.S. Fish and Wildlife Service

* = Primary responsible partner: a partner likely to take the lead, or

have an especially large role in implementing a recovery action.

Streams

CC = Cabin Creek

NFCC = North Fork Cottonwood Creek

SHC = Sharktooth Creek

SKC = Silver King Creek

STC = Stairway Creek

† Continued implementation of action expected to be necessary after

delisting.

‡ Task expected to be necessary until delisting of species.
67

Implementation Schedule for the Revised Recovery Plan for the Paiute Cutthroat Trout

PriorityNumber

ActionNumber

ActionDescription

ActionDuration(Years)

ResponsibleParties

Total Cost($1,000's)2004-2013

Cost Estimates ($by Fiscal YearFY04

FY05

F0

1 1 Remove nonnative fish from

SKC downstream fromLlewellyn Falls to barriers inSKC Canyon 

3 CDFG*

FSFWS

801010

30 44

2533

233

1 2 Reintroduce Paiute cutthroat

trout into renovated streamreaches in historic habitat inlower SKC

5 CDFG*

FS

38  2

1 3.2.7 Construct a second barrier on

lower NFCC 

3 FS* 105 35 3

1 4.1.2 Prevent exotic fish introductions

into Paiute cutthroat trout waters 

Ongoing† CDFG 20 2 2 2 

Priority 1 actions subtotal 265 40 68 6

2 3.1.1 Institute a habitat monitoring

program

Periodic‡ FS* Unknown

2 3.1.2 Monitor and manage amount of

recreational trail and campsiteuse adjacent to occupied habitatsin SKC watershed

Ongoing† FS* 10 1 1 1 

2 3.1.3 Protect Paiute cutthroat trout

habitat from effects of grazing inSKC watershed 

Periodic† FS*

FWS

Unknown
Implementation Schedule for the Revised Recovery Plan for the Paiute Cutthroat Trout

PriorityNumber

ActionNumber

ActionDescription

ActionDuration(Years)

ResponsibleParties

Total Cost($1,000's)2004-2013

Cost Estimates ($by Fiscal YearFY04

FY05

F0

68

2 3.1.4 Conduct periodic surveys in

SKC to detect reinvasion bybeavers 

Periodic‡ FS*

CDFG

 2 0.5

2 3.1.5 Remove beavers from SKC

watershed if detected anddismantle dams and lodges if anyare built

Periodic† CDFG*

FS

Unknown

2 3.2.1 Conduct periodic habitat surveys

at NFCC

Periodic‡ FS* Unknown

2 3.2.2 Continue to enforce road closure

barriers in NFCC at existing andpotential access points

Ongoing‡ FS* 10 1 1 1 

2 3.2.3 Protect Paiute cutthroat trout

habitat in NFCC from effects ofgrazing 

Periodic† FS*

FWS

Unknown

2 3.2.4 Maintain recreation opportunities

as primitive and semi-primiticein NFCC

Ongoing† FS* Unknown

2 3.2.5 Conduct periodic surveys in

NFCC to detect reinvasion bybeavers 

Periodic‡ FS*

CDFG

0.3250.325

2 3.2.6 Remove beavers in NFCC if

detected and dismantle dams andlodges if any are built. 

Periodic† CDFG*

FS

Unknown
Implementation Schedule for the Revised Recovery Plan for the Paiute Cutthroat Trout

PriorityNumber

ActionNumber

ActionDescription

ActionDuration(Years)

ResponsibleParties

Total Cost($1,000's)2004-2013

Cost Estimates ($by Fiscal YearFY04

FY05

F0

69

2 3.2.8 Develop and implement

solutions for other identifiedhabitat problems in NFCC 

Periodic FS*

FWS

Unknown

2 3.3.2 Protect Paiute cutthroat trout

habitat from effects of grazing inCC

Periodic† FS*

FWS

Unknown

2 4.1.1 Maintain a seasonal guard in

upper SKC

Ongoing† CDFG*

FS

1010

11

11

11

2 4.3.3 Assess integrity of barriers in

SKC

Ongoing‡ FS*

CDFG

 4 3.5

0.40.35

0.40.35

00

2 4.3.4 Mix populations in SKC as

necessary to maintain geneticdiversity

5 CDFG*

FSFWS

 8 1 1

2 4.4.2 Evaluate the potential for

occurrence of hybrid trout inNFCC 

Ongoing‡ CDFG*

FSFWS

 3 1 1

0.30.10.1

0.30.10.1

000

2 4.4.3 Assess integrity of barriers in

NFCC

Ongoing‡ FS*

CDFG

 2 1.75

0.20.17

0.20.17

00

2 4.4.4 Mix populations in NFCC as

necessary to maintain geneticdiversity

1 CDFG*

FSFWS

Unknown

2 4.5.4 Mix populations in STC, SHC,

and CC as necessary to maintaingenetic diversity

Periodic CDFG*

FSFWS

Unknown
Implementation Schedule for the Revised Recovery Plan for the Paiute Cutthroat Trout

PriorityNumber

ActionNumber

ActionDescription

ActionDuration(Years)

ResponsibleParties

Total Cost($1,000's)2004-2013

Cost Estimates ($by Fiscal YearFY04

FY05

F0

70

Priority 2 actions subtotal 69.4 5.63 5.63 5

3 3.1.6 Develop and implement

solutions for other identifiedproblems in SKC

Periodic CDFG*

FS*FWS

 1.6 1.6 1.6

000

3 3.3.1 Conduct periodic habitat surveys

in STC, SHC, and CC

Periodic‡ FS* 25 12.5 1

3 3.3.3 Develop and implement

solutions for other identifiedhabitat problems in STC, SHC,and CC

Periodic CDFG*

FSFWS

 0.33 0.33 0.33

3 4.2 Review existing laws and

regulations and proposenecessary changes 

Ongoing CDFG* 2 1

3 4.3.1 Monitor abundance and age class

composition in SKC

Ongoing‡ CDFG*

FS

7010

71

71

71

3 4.3.2 Evaluate the potential for

occurrence of hybrid trout inSKC 

Ongoing‡ CDFG*

FSFWS

 9 1 1

0.90.10.1

0.90.10.1

000

3 4.3.5 Develop and implement actions,

as needed, to protect geneticintegrity in SKC

Periodic CDFG*

FWSFS

Unknown

3 4.4.1 Monitor abundance and age class

composition in NFCC

Ongoing‡ CDFG*

FS

3010

31

31

31
Implementation Schedule for the Revised Recovery Plan for the Paiute Cutthroat Trout

PriorityNumber

ActionNumber

ActionDescription

ActionDuration(Years)

ResponsibleParties

Total Cost($1,000's)2004-2013

Cost Estimates ($by Fiscal YearFY04

FY05

F0

71

3 4.4.5 Develop and implement actions,

as needed, to protect geneticintegrity in NFCC

Periodic CDFG*

FWSFS

Unknown

3 4.5.1 Monitor abundance and age class

composition in STC, SHC, andCC

Periodic‡ CDFG*

FS

 15 25 12.5

51

3 4.5.2 Evaluate the potential for

occurrence of hybrid troutcomposition in STC, SHC, andCC

Periodic‡ CDFG*

FS

 4 1

10

3 4.5.3 Assess integrity of barriers in

STC, SHC, and CC

Periodic‡ CDFG*

FS

 0.75 0.5

00

3 4.5.5 Develop and implement actions,

as needed, to protect geneticintegrity in STC, SHC, and CC

Periodic CDFG*

FWSFS

Unknown

3 4.6 Explore additional out-of-basin

locations

Ongoing CDFG*

FWSFS

Unknown

3 5.1 Develop long-term conservation

plan

2 CDFG*

FWSFS

12

3 5.2 Develop a conservation

agreement

2 CDFG*

FWSFS

Unknown
Implementation Schedule for the Revised Recovery Plan for the Paiute Cutthroat Trout

PriorityNumber

ActionNumber

ActionDescription

ActionDuration(Years)

ResponsibleParties

Total Cost($1,000's)2004-2013

Cost Estimates ($by Fiscal YearFY04

FY05

F0

72

3 6.1 Manufacture and post

informational signs

4 FS* 4 1 1 1 

3 6.2 Notify user public of restoration

goals, chemical treatments, andfuture management

5 CDFG*

FSFWS

 6 1 1

1.50.20.2

1.50.20.2

100

Priority 3 actions subtotal 224.05 17 41 4

Total Estimated Cost of Recovery: $558,450 + additional costs that cannot be estimated at this time.

Total costs of recovery for ongoing and periodic tasks are calculated based on the projected 10-ye

delisting. Costs of certain tasks (i.e., those relating to developing and implementing additional actions to integrity, developing solutions to future land use conflicts, protecting habitat from impacts due to potentiof grazing management, exploring additional out-of-basin locations, removal of beavers that may coloniztrout habitat, and developing a conservation agreement) cannot be estimated because their scope and the them will be dependent on future events or obtaining additional information.
73

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Classification of Silver King Creek, Carson Ranger District, Toiyabe National

Forest. USDA Forest Service, Region 4.

Wong, D.M. 1975. Aspects of the life history of the Paiute cutthroat trout, Salmo

clarki seleniris Snyder, in North Fork Cottonwood Creek, Mono County,

California, with notes on behavior in a stream aquarium. M.A. thesis, Calif.

State Univ., Long Beach. 178 pp.

Zweifel, R.G. 1955. Ecology, distribution, and systematics of frogs of the Rana

boylei group. University of California Publications in Zoology 54(4):207-292.

Zweifel, R.G. 1968. Rana muscosa. Catalog of American amphibians and reptiles,

65:1-2.

B. In Litt. References

Ryan, J.H. 1982. Memorandum, dated December 14, 1982, from Region 2, California

Department of Fish and Game, to Survey Files on annual monitoring of Silver

King Creek, Alpine County, California. 5 pp. 
80

C. Personal Communications

Becker, Dawne. 2001. California Department of Fish and Game.

Hubbs, Del. 2002. U.S. Forest Service.

May, Bernard. 2001. University of California - Davis.

Shanley, Pat. 2000. U.S. Forest Service.

Somer, William. 2001-2002. California Department of Fish and Game.

Strand, Phil. 2002-2003. Sierra National Forest, U.S. Forest Service.

Wong, Darrell. 2000. California Department of Fish and Game.
A-1

APPENDIX A. Summary of General Aquatic Wildlife System (GAWS)

Survey Locations, Sediment Sampling, and

Macroinvertebrate Sampling

Table A1. Summary of GAWS station site characteristics (Modified from Duff

1985).

Stream Station Elevation

(m)

Gradient Channel

Width

(m)

Water

Depth

(m)

Riffle/Pool

Ratio

Reach

Length

(m)

Silver King S1:610 2457 2.0 7.92 0.26 40/60 150

Silver King S2:640 2463 2.5 9.79 0.25 24/76 374

Silver King S3:641 2465 2.0 8.10 0.22 70/30 296

Silver King S4:700 2454 2.0 11.4 0.14 12/88 150

Silver King S5:725 2484 1.0 7.4 0.17 20/80 150

Silver King S6:738 2486 2.0 9.58 0.24 52/48 150

Silver King S6A:745 2488 2.0 8.36 0.17 45/55 150

Silver King S7:775 2499 2.0 5.72 0.16 31/69 150

Silver King S8:813 2505 2.5 6.42 0.12 15/85 150

Bull

Canyon

S1:040 2463 2.5 5.64 0.24 50/50 150

Bull

Canyon

S2:100 2475 4.5 6.86 0.095 33/67 150

Fly Valley S1:500 2646 3.0 2.76 0.82 20/80 150

Four Mile S1:250 2560 2.5 3.27 0.15 17/83 300

Coyote S1:400 2484 1.0 2.9 0.10 60/40 150

Coyote S2:467 2489 1.5 3.8 0.84 60/40 150

Coyote S3:500 2492 1.0 2.76 0.12 60/40 150

Coyote S4:542 2498 2.0 2.56 0.11 55/45 150

Corral S1:571 2525 2.5 2.5 0.14 55/45 150

Corral S2:574 2532 3.0 2.46 0.33 40/60 240

 Five transects were measured within each reach. Channel (bankfull) width is the

average width of all five transects. Water depth is the average water depth taken over

all 5 transects (15 to 20 depth measurements were taken at each of the 5 transects,75-

100 measurements). Station locations are identified in Figures A-1 and A-2.
A-2

Figure A1. Location of GAWS stations on Silver King, Four Mile Canyon, Fly Valley, 

and Bull Canyon Creeks, Alpine County, California. 
A3

Figure A2. Location of GAWS stations on Corral Valley and Coyote Valley Creeks, Alpine County, Cal
A-4

Table A2. Summary of sediment samples collected in 1984 and 1990 (Modified

from Duff 1991).

Stream Station Percent Fines Passing Sieve

>6.35 mm >0.84 mm >0.21 mm <6.35 mm

Silver King S1:610 --- --- --- ---

Silver King S2:640 64.3 (60.3) 21.8 (20.4) 13.9 (19.3) 35.7 (39.7)

Silver King S3:641 61.8 (53.4) 23.1 (30.8) 15.1 (15.8) 38.2 (46.6)

Silver King S4:700 57.0 (61.5) 20.2 (21.9) 22.8 (16.6) 43.0 (38.5)

Silver King S5:725 57.3 (59.0) 25.5 (24.7) 17.2 (16.3) 42.7 (41.0)

Silver King S6:738 59.3 (68.6) 24.7 (15.7) 16.0 (15.7) 40.7 (31.4)

Silver King S6A:745 --- --- --- ---

Silver King S7:775 64.8 (57.6) 25.6 (28.0) 9.6 (14.4) 35.2 (42.4)

Silver King S8:813 60.0 (64.2) 29.0 (25.5) 11.0 (10.6) 40.0 (35.8)

MEAN 60.6 (60.7) 24.3 (23.8) 15.1 (15.5) 39.4 (39.3)

Bull Canyon S1:040 62.9 (61.0) 20.9 (23.5) 16.2 (15.5) 37.1 (39.0)

Bull Canyon S2:100 --- --- --- ---

Fly Valley S1:500 62.9 (67.9) 24.3 (26.7) 12.8 (5.4) 37.1 (32.1)

Four Mile S1:250 69.6 (72.4) 20.4 (18.5) 10.0 (9.1) 30.4 (27.6)

Coyote S1:400 --- --- --- ---

Coyote S2:467 32.2 (41.0) 38.3 (39.5) 29.5 (19.5) 67.8 (59.0)

Coyote S3:500 44.5 (52.1) 36.5 (31.1) 19.0 (16.8) 55.5 (47.9)

Coyote S4:542 --- --- --- ---

MEAN 38.4 (46.6) 37.4 (35.3) 24.3 (18.2) 61.7 (53.5)

Corral S1:571 51.8 (51.0) 30.4 (32.0) 17.8 (17.0) 48.2 (49.0)

Corral S2:574 45.7 (46.9) 27.3 (36.0) 27.0 (17.1) 54.3 (53.1)

MEAN 48.8 (49.0) 28.9 (34.0) 22.4 (17.1) 51.3 (51.1)

Values outside parentheses represent 1990 data and values inside parentheses

represent data from 1984.
A-5

Table A3. Summary of macroinvertebrate diversity index (DAT) ratings from

1984, 1987, and 1990. (Modified from Mangum 1991)

Stream Station Channel

Type

DAT

1984

DAT

1987

DAT

1990

Silver King S1:610 C3 --- --- ---

Silver King S2:640 C3 24.3 17.8 25.0

Silver King S3:641 C3 21.7 12.3 20.2

Silver King S4:700 C3 20.1 19.2 21.1

Silver King S5:725 C3 17.4 20.5 20.9

Silver King S6:738 C3 17.5 13.8 17.5

Silver King S6A:745 C3 --- --- ---

Silver King S7:775 B2/B3 15.6 19.1 20.0

Silver King S8:813 C3 11.2 18.3 20.3

Bull Canyon S1:040 C3 --- --- ---

Bull Canyon S2:100 B2 17.8 21.2 ---

Fly Valley S1:500 B2/C2 20.8 17.5 ---

Four Mile S1:250 C3 19.8 21.1 16.4

Coyote S1:400 C6 14.9 17.1 ---

Coyote S2:467 C3 --- --- ---

Coyote S3:500 C6 17.3 14.9 ---

Coyote S4:542 C3 --- --- ---

Corral S1:571 C3 17.9 18.8 ---

Corral S2:574 C3 --- --- ---

Scale Macroinvertebrate Diversity Index

Excellent 18 - 26

Good 11 - 17

Fair 6 - 10

Poor 0 - 5
A-6

Table A4. Summary of macroinvertebrate standing crop data from 1984, 1987,

and 1990. (Modified from Mangum 1991)

Stream Station Channel

Type

Standing

Crop g/m2

1984

Standing

Crop g/m2

1987

Standing

Crop g/m2

1990

Silver King S1:610 C3 --- --- ---

Silver King S2:640 C3 5.6 1.3 1.1

Silver King S3:641 C3 3.1 0.9 0.5

Silver King S4:700 C3 1.0 0.7 1.1

Silver King S5:725 C3 2.5 4.0 0.5

Silver King S6:738 C3 2.1 0.8 0.6

Silver King S6A:745 C3 --- --- ---

Silver King S7:775 B2/B3 1.6 1.1 2.6

Silver King S8:813 C3 0.9 1.0 1.0

Bull Canyon S1:040 C3 --- --- ---

Bull Canyon S2:100 B2 0.5 0.8 ---

Fly Valley S1:500 B2/C2 1.3 0.5 ---

Four Mile S1:250 C3 1.8 2.5 1.2

Coyote S1:400 C6 1.4 1.8 ---

Coyote S2:467 C3 --- --- ---

Coyote S3:500 C6 1.1 1.6 ---

Coyote S4:542 C3 --- --- ---

Corral S1:571 C3 1.3 1.6 ---

Corral S2:574 C3 --- --- ---

Scale Macroinvertebrate Standing Crop

Excellent 4.0 - 12.0

Good 1.6 - 4.0

Fair 0.6 - 1.5

Poor 0.0 - 0.5
A-7

Table A5. Summary of macroinvertebrate Biotic Condition Index (BCI) ratings

from 1984, 1987, and 1990. (Modified from Mangum 1991)

Stream Station Channel

Type

BCI

1984

BCI

1987

BCI

1990

BCI

Desired

Silver King S1:610 C3 --- --- --- ---

Silver King S2:640 C3 96 100 100 110

Silver King S3:641 C3 96 100 100 110

Silver King S4:700 C3 93 96 100 110

Silver King S5:725 C3 100 100 98 110

Silver King S6:738 C3 91 100 89 110

Silver King S6A:745 C3 --- --- --- ---

Silver King S7:775 B2/B3 88 100 100 110

Silver King S8:813 C3 93 98 100 110

Bull

Canyon

S1:040 C3 88 --- --- ---

Bull

Canyon

S2:100 B2 --- 98 --- 110

Fly Valley S1:500 B2/C2 96 100 --- 105

Four Mile S1:250 C3 106 110 91 115

Coyote S1:400 C6 93 96 --- 110

Coyote S2:467 C3 93 --- --- 110

Coyote S3:500 C6 98 88 --- 110

Coyote S4:542 C3 --- 96 --- 110

Corral S1:571 C3 94 86 --- 105

Corral S2:574 C3 --- --- --- ---

Scale Macroinvertebrate Biotic Condition Index (BCI)

Excellent > 90

Good 75 - 89

Fair < 75

Poor < 75
B-1

APPENDIX B. Summary of Threats and Recommended Recovery Actions

for the Paiute Cutthroat Trout.

LISTING

FACTOR

THREAT RECOVERY

CRITERIA

RECOVERY ACTION NUMBERS

A Streambank degradation

from recreational activities

3 3.1.1, 3.1.2, 3.1.6, 3.2.1, 3.2.2,

3.2.4, 3.3.3

A Streambank degradation

from cattle grazing

3 3.1.1, 3.1.3, 3.1.6, 3.2.1, 3.2.3,

3.2.8, 3.3.1, 3.3.2, 3.3.3

A Degradation of water

quality and spawning

substrates by beavers

3 3.1.1, 3.1.4, 3.1.5, 3.1.6, 3.2.1,

3.2.5, 3.2.6, 3.2.8, 3.3.1, 3.3.3

B Unregulated angling 2, 4 3.1.6, 3.2.4, 3.2.8, 3.3.1, 3.3.3,

4.1.1, 4.2, 6.1, 6.2

C Natural predators [not

currently significant]

Not

Applicable

C Fungal infections 2 4.3.1, 4.4.1, 4.5.1

D Potential budgetary

constraints on agency

commitment to recovery

actions

1, 2, 3, 4, 5 4.2, 5.1, 5.2

E Hybridization and

competition with introduced

trout

1, 2, 4 1, 2, 4.1.1, 4.1.2, 4.3.2, 4.3.5,

4.4.2, 4.4.5, 4.5.2, 4.5.5

E Need for fish barriers to

prevent upstream migration

of introduced trout

1, 2, 4 1, 2, 3.2.7, 4.3.3, 4.3.5, 4.4.3,

4.4.5, 4.5.3, 4.5.5

E Human introduction of trout 1, 2, 4 1, 2, 4.1.1, 4.1.2, 4.2, 4.3.5,

4.4.5, 4.5.5, 6.1, 6.2

E Vulnerability to

catastrophic events due to

limited distribution

2, 3, 4 2, 4.3.1, 4.3.4, 4.4.1, 4.4.4, 4.5.1,

4.5.4, 4.6

Listing Factors: 

A. The Present or Threatened Destruction, Modification, or Curtailment Of Its Habitat or Range 

B. Overutilization for Commercial, Recreational, Scientific, Educational Purposes (not a factor)

C. Disease or Predation 

D. The Inadequacy of Existing Regulatory Mechanisms 

E. Other Natural or Manmade Factors Affecting Its Continued Existence
B-2

Recovery Criteria: 

1. All nonnative salmonids are removed from Silver King Creek and its tributaries downstream of

Llewellyn Falls to fish barriers in Silver King Canyon.

2. A viable population occupies all historic habitat in Silver King Creek and its tributaries downstream

of Llewellyn Falls to fish barriers in Silver King Canyon.

3. Paiute cutthroat trout habitat is maintained in all occupied streams.

4. The refuge populations in Corral and Coyote Creeks, Silver King Creek, and tributaries above

Llewellyn Falls as well as out-of-basin populations are maintained as refugia and are secured from the

introduction of other salmonid species.

5. A long-term conservation plan and conservation agreement are developed, which will be the guiding

management documents once Paiute cutthroat trout are delisted. 
C-1

APPENDIX C. Summary of Comments on the Draft Revised Recovery Plan

On January 26, 2004, we released the Draft Revised Recovery Plan for the Paiute

Cutthroat Trout for a 60 day public comment period that ended March 26, 2004. We

received 14 comment letters from respondents including various governmental

agencies, conservation organizations, and private individuals. These comments, where

appropriate, have been incorporated into the final revised recovery plan. In addition,

we offer the following discussion in the interest of providing a fuller explanation and

response to certain specific comments.

 

Issues:

Historic habitat (Comments 1-6)

1985 Recovery Plan (Comment 7)

Fisheries Management (Comments 8-11)

Fish Barriers (Comments 12-14)

Tamarack Lake (Comments 15-16)

Non-native Fish Removal (Comments 17-27)

Non target Species (Comments 28-35)

General Comments (Comments 36-70)

Historic Habitat

1. Comment: Paiute cutthroat trout have been restored already; historic range is

above Llewellyn Falls. Response: As stated in the Revised Recovery Plan, the

best available information supports the location of historic habitat from Llewellyn

Falls downstream to barriers in Silver King Canyon and all accessible tributaries

within this stream reach. 

2. Comment: Historic habitat is uncertain; barriers are present which prevent

upstream migration into presumed historic habitat. Response: See response to

Comment 1.

3. Comment: The 1985 Plan assumed that the native habitat for Paiute cutthroat

trout was above Llewellyn Falls in Silver King Creek because that is the type

locality for the subspecies. Response: The 1985 Recovery Plan states “The

presumed historic distribution of the Paiute cutthroat trout is limited to a short
C-2

reach of Silver King Creek below Llewellyn Falls and the accessible reaches of

three small tributaries: Tamarack Creek, Tamarack Lake Creek, and the lower 0.4

km of Corral Valley Creek.” The Revised Recovery Plan also states this. Neither

plan identifies the native habitat of Paiute cutthroat trout as occurring above

Llewellyn Falls.

4. Comment: Fundamental to the Plan is a claim, now, that the historic habitat of

Paiute cutthroat trout is Silver King Creek below Llewellyn Falls. The evidence

for this highly speculative claim is based on hearsay and anecdote and is variable

and contradictory in the original sources (Ryan and Nicola 1976, Vestal 1947). 

Response: Both the 1985 Recovery Plan and the 2004 Draft Revised Recovery

Plan clearly state that the historic range of Paiute cutthroat trout is from Llewellyn

Falls downstream to barriers in Silver King Canyon. This claim is documented in

a letter from Virgil S. Connell (sheep herder) to Brian Curtis (California

Department of Fish and Game) on August 8, 1944 who writes “Above the falls we

found there were no fish.” Later he writes “During the year 1912, a young Basque

Joe Jaunsaras was herding for me, and while fishing just below the falls, and

catching more than he wanted, he put some in a can and carried them above the

falls.” We have no reason to believe that Mr. Connell was not telling the truth. 

The only contradictory issue documented in Ryan and Nicola (1976) that we could

find is the date Paiute cutthroat trout were stocked above Llewellyn Falls. In

contrast to Ryan and Nicola, Ashley (1970) stated that the 1912 transplant was a

failure and Paiute cutthroat trout were replanted in 1924. We agree with the

evidence and conclusion presented in Ryan and Nicola (1976), that Paiute

cutthroat trout were successfully transplanted above Llewellyn Falls in 1912 and

that the historic range of Paiute cutthroat trout is from Llewellyn Falls downstream

to barriers in Silver King Canyon. The historic habitat for Paiute cutthroat trout is

also reported in Behnke (1979).

5. Comment: There is no reason and no new scientific information to alter the

conclusion given in the 1985 Recovery Plan that stated “The issue of what

constitutes the native range is complicated by the paucity of early collection

records and the conflicting recollections of early observers.” (1985 Recovery Plan,

p. 7). Therefore, the type locality above Llewellyn Falls must be accepted as the

historic range of Paiute cutthroat trout. Response: The 1985 Recovery Plan and

this final Revised Recovery Plan conclude that the best available information

supports the location of historic habitat from Llewellyn Falls downstream to

barriers in Silver King Canyon and all accessible tributaries within this stream

reach. 

6. Comment: How could Paiute cutthroat trout have existed in such a limited length

of stream for perhaps thousands of years; but now, occupying twice as much

stream and in five times as many drainages, it is at risk from catastrophic events? 
C-3

Response: All existing populations are isolated in headwater drainages which

make them susceptible to catastrophic events (Dunham et al. 2003, Reiman et al.

2003). Paiute cutthroat trout will always be susceptible to stochastic events

because of their limited range. When Paiute cutthroat trout are repatriated

throughout their historic range, they will be less susceptible than the out-of-basin

populations due to the size of the drainage, the size of the population, and the

quality and distribution of habitat in which it evolved.

1985 Recovery Plan

7. Comment: The 1985 Plan states “At what point or condition can the species be

considered recovered?” which is answered “When a pure population of Paiute

cutthroat trout has been reestablished in Silver King Creek above Llewellyn Falls,

and the integrity of the habitats in Silver King Creek, North Fork Cottonwood

Creek, and Stairway Creek has been secured and maintained over a consecutive

five-year period with stable or increasing overwintering populations of 500 or

more adult fish in each of these streams”. These conditions have been met. 

Response: Most of the objectives of the 1985 Recovery Plan have been

accomplished. However, the 1985 Recovery Plan did not address recovery in

terms of restoring Paiute cutthroat trout into its historic range because the barriers

in Silver King Canyon had not been investigated. The 2004 Draft Revised

Recovery Plan addressed new information concerning these natural barriers. 

California Department of Fish and Game, Forest Service, and U.S. Fish and

Wildlife Service personnel have investigated the existence of natural fish barriers

in Silver King Canyon and have concluded that these barriers prevent fish from

migrating upstream into Paiute cutthroat trout habitat. These barriers are the likely

downstream extent of historic habitat as they form a barrier that isolates Paiute

cutthroat trout from historic Lahontan cutthroat trout habitat. Therefore, this final

Revised Recovery Plan incorporates this new information to address recovery in

terms of restoring Paiute cutthroat trout into their historic habitat, from Llewellyn

Falls downstream to Silver King Canyon.

Fisheries Management

8. Comment: The Plan is a marketing scheme to permit fishing for threatened trout. 

Response: The purpose of the Revised Recovery Plan is to identify actions that

are needed, and criteria that must be met, for the recovery and delisting of Paiute

cutthroat trout as a threatened species under the Endangered Species Act.

9. Comment: The plan fails to address the root causes of risks to Paiute cutthroat

trout, namely the stocking of nonnative trout in any part of the watershed in which
C-4

stocked fish can eventually migrate into existing and historic habitat. There can be

no long-term restoration of native fish as long as fish stocking by fish and game

agencies and U.S. Fish and Wildlife Service continues in the drainages of concern. 

Response: The California Department of Fish and Game has not stocked

nonnative trout in the Silver King Canyon drainage since the early 1950’s and

there is no plan to stock in the future. 

10. Comment: It is disturbing that the reason Paiute cutthroat trout were downlisted

to facilitate management and allow for regulated angling, the Endangered Species

Act was not established to promote fishing. Response: Paiute cutthroat trout,

Lahontan cutthroat trout, and Apache trout were all downlisted to threatened status

at the same time and for the same reasoning (U.S. Fish and Wildlife Service 1975). 

It was determined that regulated angling could be used as a management tool for

these species if streams became overpopulated, and take was authorized in

accordance with applicable State law. However, since downlisting occurred,

fishing has not been allowed in upper Silver King Creek or North Fork

Cottonwood Creek, which are the two most accessible Paiute cutthroat trout

occupied streams.

11. Comment: Opening Silver King Creek above Llewellyn Falls to angling, now

closed, will increase the risk to Paiute cutthroat trout of hybridization. Paiute

cutthroat trout now exist in the stream section below Llewellyn Falls because some

fish go over the falls and on the barrier on Coyote and Corral creeks and are

available for anglers to catch in the lower section of Silver King Creek below

Llewellyn Falls which is presently open to angling. The unique experience of

catching Paiute cutthroat trout in their native drainage is provided currently. Does

the U.S. Fish and Wildlife Service see no contradiction in recommending fishing

above Llewellyn Falls where the population is claimed to be finally secured? If

the stream reach below Llewellyn Falls is converted to a monospecific population

of Paiute cutthroat trout, it will always be at risk of introductions of non-native fish

into any tributaries above Llewellyn Falls or into Corral Valley or Coyote Valley

Creeks anyway. There is no reason to assume that non-native fish could only be

introduced into the most accessible area. Response: Very few fish go over the

falls as supported by the fact that electrofishing efforts have not found Paiute

cutthroat trout below the falls. A highly regulated fishery has been discussed

above Llewellyn Falls during the non-native fish eradication efforts to offset any

public fishing lost during this time. This would not occur unless the Paiute

cutthroat trout population is large enough to support fishing and a stream guard

(Action 4.1.1) is in place to monitor fishing activity. The California Department of

Fish and Game is responsible for the management of Paiute cutthroat trout. Any

regulations relating to angling would be subject to the 4(d) provisions of the

Endangered Species Act. 
C-5

Fish Barriers

12. Comment: Construction of barriers within wilderness areas contradicts the intent

of the Wilderness Act. Response: No barrier construction or removal is planned

in any wilderness area. Recovery Action 3.2.7 describes construction of a fish

barrier in North Fork Cottonwood Creek which is not in a designated wilderness.

13. Comment: The success of the current plan-that is, restoring and maintaining

genetically pure Paiute cutthroat trout in the lower portion of the Silver King

Creek drainage-is highly dependent on whether or not these “potential barriers”

will in fact prevent movement of other native and introduced trout from portions of

the drainage below Silver King Canyon. The Plan assumes that reinvasion can be

prevented by monitoring the identified natural barriers or establishing artificial

instream barriers. It appears the assumption that reinvasion of lower Silver King

Creek is unlikely needs to be qualified as “uncertain” (even setting aside the

possibility of human reintroduction). If stream barriers have limited effectiveness

in preventing fish migration, the plan fails to address effectiveness of barriers at all

flow conditions. Response: California Department of Fish and Game, Forest

Service, and U.S. Fish and Wildlife Service personnel have documented the

existence of natural fish barriers in Silver King Canyon, and surveys support the

conclusion that these barriers are effective in stopping fish from migrating

upstream into historic Paiute cutthroat trout habitat regardless of the flow

conditions. 

14. Comment: Permanent barriers of some kind would have been necessary for the

genetic isolation of the precursor of Paiute cutthroat trout. Once isolated, Paiute

cutthroat trout evolved. The barriers in Silver King Canyon are apparently not

large enough for this original isolation or the U.S. Fish and Wildlife Service would

not be recommending that they be inspected and reinforced to prevent upstream

migration of other non-native fish. Response: The Plan does not recommend

reinforcing natural barriers in Silver King Canyon. Periodic monitoring of the

natural barriers is needed to document effectiveness and any changes in the

barriers due to stochastic events. 

Tamarack Lake

15. Comment: Treatment of Tamarack Lake is not necessary for Paiute cutthroat

trout recovery because any non-native fish in Tamarack Lake are isolated from the

Silver King Creek drainage by barriers. The poisoning of Tamarack Lake is
C-6

uncalled for and should be dropped from the Plan. Response: Barriers are present

and are effective in stopping fish from moving upstream into Tamarack Lake. 

However, it is necessary to treat Tamarack Lake because of the possible existence

there of non-native trout, which have been stocked in the past and could migrate

downstream into Silver King Creek during high flow events. 

16.Comment: Alternatives such as gill netting in Tamarack Lake should be

considered. Response: Alternatives, including gill netting, were analyzed through

the National Environmental Policy Act process (Environmental Assessment) and

section 7(a)(2) of the Endangered Species Act (Biological Assessment, and

Biological Opinion) and it was determined that treating Tamarack Lake was the

most effective method for achieving recovery goals.

Non-native Fish Removal

17.Comment: The Plan calls for stream poisoning, which is unsound and will create

ecological havoc on amphibians and macroinvertebrates. The Plan should address

other alternatives to poisoning. Response: An Environmental Assessment has

been completed for the rotenone treatment. Furthermore, the U.S. Fish and

Wildlife Service, California Department of Fish and Game, and the HumboldtToiyabe National Forest have been planning for the reintroduction of Paiute

cutthroat trout into its historic range for many years. All methods for the removal

of non-native fish have been discussed at length and analyzed for all biological

resources through the National Environmental Policy Act process in the Forest

Services’ Environmental Assessment and through section 7(a)(2) of the

Endangered Species Act (Biological Assessment, and Biological Opinion).

18.Comment: Plan fails to examine effects of poisoning on amphibians. Response:

The effects of individual recovery actions, including use of rotenone, were

analyzed through the National Environmental Policy Act process (Environmental

Assessment) and section 7(a)(2) of the Endangered Species Act (Biological

Assessment, and Biological Opinion). 

19.Comment: The recommended killing of endangered amphibians through

poisoning is a far cry from the euphemistic statement “there may be some negative

impacts on amphibians if they are not captured during the relocation process or

through stress of handling”. Since the plan recommends killing imperiled

amphibians and disrupting of aquatic food webs via poisoning, it is incorrect to

state “all Paiute cutthroat trout recovery actions were evaluated to minimize

adverse impacts to mountain yellow-legged frog and Yosemite toad.” Response:

The Plan does not recommend killing amphibians through this conservation effort. 
C-7

Surveys will be performed to relocate amphibians throughout the treatment area to

outside of the treatment area. During amphibian surveys in 2003, no mountain

yellow-legged frogs were found. Approximately 12 toad tadpoles were found and

relocated outside the treatment area into suitable habitat. The lakes in Silver King

Creek drainage will remain fishless for the ultimate benefit of amphibians.

20.Comment: Use of rotenone conflicts with wilderness values. Response: The

Wilderness Act of 1964 allows for activities within wilderness boundaries when it

involves the protection and propagation of threatened and endangered species. 

Section 4(b) of the Wilderness Act and House Report 98-40, which supplements

the California Wilderness Act of 1984, establishing the Carson-Iceberg

Wilderness, specifically states that “certain wildlife management activities,

designed to enhance or restore fish populations, are permissible and often desirable

in wilderness areas to aid in achieving the goal of preserving the wilderness

character of the area”. Guidelines for managing fish and wildlife in wilderness are

found in Forest Service Manual 2323.3. This direction allows for the use of

chemical treatments to prepare waters for reestablishment of indigenous,

threatened or endangered, or native species, or to correct undesirable conditions

caused by human influence.

21.Comment: The plan provides no evaluation or determination of success criteria or

the purpose and need for subsequent chemical treatments. Success and retreatment criteria need to be established based on feasibility and risk assessment. 

Response: The success criterion is described in action 1 “Chemically treat Silver

King Creek to remove all introgressed fish downstream from Llewellyn Falls to

barriers in Silver King Canyon.” Two to three treatments are often necessary to

remove all non-native fish from a certain stream segment. 

22.Comment: Several issues relating to the adverse effects of rotenone use. 

Response: The Revised Recovery Plan provides actions that are needed for the

recovery of Paiute cutthroat trout. The effects of individual recovery actions were

analyzed through the National Environmental Policy Act process (Environmental

Assessment) and section 7(a)(2) of the Endangered Species Act (Biological

Assessment, and Biological Opinion). This analysis concluded that the use of

rotenone was the most effective method of achieving recovery goals. It also

documented that the use of rotenone will be done in compliance with all applicable

laws and regulations.

23.Comment: The Plan states that “Chemically treating Silver King Creek to remove

all introgressed fish” jumps the gun by stating that chemicals would be used to

eradicate nonnative fish when this has not been determined through a National

Environmental Policy Act Environmental Assessment or Environmental Impact
C-8

Report/Environmental Impact Statement process. It also reveals the preconceived

bias that poisons are the only effective means of achieving the goals of the project. 

Response: See response to Comment 17.

24.Comment: The Plan is an attempt to justify another large stream poisoning

project in a Wilderness Area for the purpose of establishing a monospecific

sportfishery for Paiute cutthroat trout that will be part of a California Department

of Fish and Game angling contest for “heritage” trout. Response: See response to

Comment 8.

25.Comment: The Plan fails to show why poisoning 11 miles of streams, springs,

and a lake would benefit either Paiute cutthroat trout or the many other nontarget

species that would be affected and endangered by this project. Response: The

plan clearly states that recovery of Paiute cutthroat trout will require repatriation

into historic habitat. To accomplish this task, nonnative salmonids, which are the

most serious threat to Paiute cutthroat trout, must be eradicated from Llewellyn

Falls downstream to Silver King Canyon. Amphibians will benefit by the removal

of nonnative fish in Tamarack Lake within the Silver King Creek drainage. 

26.Comment: The Draft Plan concludes that reintroduction to “native habitat”

(below Llewellyn Falls) will somehow “substantially reduce these extinction

threats.” This reasoning is flawed and is constructed merely to justify another

poisoning project in Silver King Creek for other purposes. Response: The

purpose of this project is to reduce the threat of nonnative trout to Paiute cutthroat

trout by removing nonnative trout from its historic habitat so Paiute cutthroat trout

can then be reintroduced into Silver King Creek which will create a more secure

population through connecting the existing isolated populations. These actions are

necessary for the recovery and delisting of Paiute cutthroat trout as a threatened

species under the Endangered Species Act.

27.Comment: There is no recognition in this Draft Plan that poisoning is a major

habitat disturbance that can have long reaching and permanent effects on nontarget

species and food supplies which are a component of habitat. Response: Effects to

nontarget species are expected to be short-term due to the concentration of

chemicals used, exposure time, and untreated adjacent and upstream habitat which

will provide source populations for recolonization. The effects of individual

recovery actions were analyzed through the National Environmental Policy Act

process (Environmental Assessment) and section 7(a)(2) of the Endangered

Species Act (Biological Assessment, and Biological Opinion).
C-9

Non Target Species

28. Comment: Opposes any action that may contribute to the need to federally list the

mountain yellow-legged frog and Yosemite toad. Response: As stated in the

Revised Recovery Plan, once treated, Tamarack Lake will remain fishless for the

benefit of amphibians. Whitecliff Lake, outside the treatment area, will also

remain fishless. Additionally, amphibian surveys will be conducted in the project

area. If any are found, they will be transported out of the project area prior to

treatment. By ensuring that conservation measures are used, these projects should

not lead to the need to federally list the mountain yellow-legged frog or Yosemite

toad.

29. Comment: Macroinvertebrate and amphibian monitoring is inadequate. 

Response: The adequacy of macroinvertebrate and amphibian monitoring has

been analyzed through both the National Environmental Policy Act process and

section 7(a)(2) of the Endangered Species Act. Amphibians in the drainage have

been specifically surveyed by the California Department of Fish and Game in

2001, as well as incidentally in the course of Paiute cutthroat trout surveys, and the

treatment area will be surveyed for amphibians prior to rotenone application. 

Amphibian surveys will continue as part of post-treatment monitoring. A detailed

macroinvertebrate sampling plan, including control sites and pre- and posttreatment surveys, was included as an appendix to the Environmental Assessment

and was accepted by the Lahontan Regional Water Quality Control Board as

adequate to address their concerns and meet Basin Plan Objectives.

30. Comment: Evidence clearly demonstrates that multiple rotenone treatments and

livestock grazing have decimated amphibian populations in the project area and

there is no evidence that native Paiute cutthroat trout have less impact on

amphibians than nonnative fish. Response: The project area has never been

treated with rotenone and we are unaware of any information that documents the

decimation of amphibian populations in this area due to rotenone treatments. 

Livestock grazing has occurred in the area for over 100 years and probably has had

an effect on amphibians, however, we have little information to support this. The

only location where mountain yellow-legged frogs in Silver King Creek currently

exist is above Llewellyn Falls, where they are coexisting with Paiute cutthroat

trout.

31. Comment: Various issues relating to the adverse effects of recovery actions to

macroinvertebrates. Response: The Revised Recovery Plan provides actions that

are needed for the recovery of Paiute cutthroat trout. Macroinvertebrate sampling

is a component of these actions. The effects of individual recovery actions have

been analyzed through the National Environmental Policy Act process
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(Environmental Assessment) and section 7(a)(2) of the Endangered Species Act

(Biological Assessment, and Biological Opinion).

32. Comment: The U.S. Fish and Wildlife Service, the agency responsible for

endangered species, should have analyzed effects to nontarget species in this Draft

Plan. Instead the Draft Plan is a myopic, single species approach to increasing

numbers of one species for sport fishing. It was never the intent of the Endangered 

Species Act to conduct recovery projects to increase single species that would put

other species at risk of extinction. Response: The Revised Recovery Plan

provides actions that are needed for the recovery of Paiute cutthroat trout. 

Addressing the effects of these actions to nontarget species is not within the scope

of this recovery plan. The effects of individual recovery actions, including effects

to nontarget species, have been, and will continue to be analyzed through the

National Environmental Policy Act process (Environmental Assessment) and

section 7(a)(2) of the Endangered Species Act (Biological Assessment, and

Biological Opinion).

 

33. Comment: The Draft Plan makes no effort to assess the cumulative impacts to

such species as the mountain yellow-legged frog, Yosemite toad, willow

flycatcher, the yellow warbler, and hundreds of other species of all this poisoning

being conducted in other nearby watersheds or of all the past poisoning in the

Silver King drainage or in many other watersheds across the Sierra. Response: 

Addressing the cumulative impacts of recovery actions to other species is not

within the scope of this recovery plan. However, these impacts were analyzed

through the National Environmental Policy Act process (Environmental

Assessment) and section 7(a)(2) of the Endangered Species Act (Biological

Assessment, and Biological Opinion). 

34. Comment: On the whole, this proposed management plan, far from benefiting

native amphibians, will only further deteriorate their habitat in several locations. 

One of the more misleading statements in this Draft Plan is the sentence on p. 9

that “the long-term effects of removal of nonnative and hybrid fish will be

beneficial to native amphibians.” We know of no studies that show Paiute

cutthroat trout are less an impact on amphibians than are other trout. Response: 

Recovery actions include the removal of nonnative trout from Tamarack Lake to

prevent their reintroduction downstream into Silver King Creek during high flow

events. Mountain yellow-legged frogs historically occupied this lake. Although

the exact reason for their disappearance is unknown, it is believed that the stocking

of nonnative trout into this once fishless lake contributed to their disappearance. 

There are no plans to introduce Paiute cutthroat trout into Tamarack or Whitecliff

Lakes. Therefore, it is anticipated that a secondary benefit of removing nonnative

trout from Tamarack Lake, and managing Tamarack and Whitecliff Lakes to

remain fishless, will contribute to the conservation of amphibians. 
C-11

35. Comment: The assumption that “because this recovery plan is partially focused

on habitat improvements, it also provides conservation benefits for two candidate

species, the Sierra Nevada population of the mountain yellow-legged frog and the

Yosemite toad” (Plan at 48) requires substantially more robust supporting analysis

than the Plan currently offers. Response: See response to Comment 34.

General Comments

36. Comment: Have potential impacts from the 1997 flood and/or other natural

events that have occurred since the last habitat monitoring was conducted been

investigated in the proposed recovery areas, and has it been determined that the

fish barriers are still effective? Response: Numerous trips into Silver King

Canyon by California Department of Fish and Game, Forest Service, and U.S. Fish

and Wildlife Service personnel after the 1997 flood have documented that the

natural fish barriers in Silver King Canyon are still effective in stopping fish from

migrating upstream into historic Paiute cutthroat trout habitat.

37. Comment: The project area is projected to reopen to angling after one to three

years of treatment. What criteria and methods will be used to monitor the Paiute

cutthroat trout populations and protect the restored populations from declining due

to even limited fishing pressure? Response: The California Department of Fish

and Game is responsible for the management of Paiute cutthroat trout. Any

regulations relating to angling would be subject to the 4(d) provisions of the

Endangered Species Act and state laws and regulations. Permitted recreational

fishing will not occur unless the population is stable enough to sustain such an

activity and a stream guard is in place to monitor fishing. 

38. Comment: Have alternative plans been investigated to ensure the removal project

is a success and that the required monitoring occurs in the event budgetary

constraints limit the funding and/or staff available? Response: The U.S. Fish and

Wildlfie Service, California Department of Fish and Game, and the Forest Service

have all committed to the recovery of Paiute cutthroat trout and will continue to

request appropriate funding to carry out recovery actions. The levels of funding

which are actually authorized for these efforts on a yearly basis are appropriated

by Congress and are beyond agency control.

39. Comment: Any use of rotenone by California Department of Fish and Game must

conform to the Water Quality Control Plan for the Lahontan Region and

Memorandum of Understanding requirements signed by California Department of

Fish and Game and the Board. Response: Reporting requirements signed by

California Department of Fish and Game and the Board were incorporated into the
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Terms and Conditions in our Biological Opinion for this project. The project will

not be carried out without the appropriate permits from these and other agencies.

40. Comment: The collaboration of agency efforts should have resulted in a

consistent and supportive group of documents that reflects awareness for all

inherent subjects of this recovery plan (wilderness, amphibians, and public

interests). Response: We believe there is consistent and supporting

documentation throughout the documents relating to the Revised Recovery Plan,

National Environmental Policy Act compliance (Environmental Assessment),

section 7(a)(2) of the Endangered Species Act compliance (Biological Assessment

and Biological Opinion), and California State Environmental Quality Act

compliance.

41. Comment: The California Department of Fish and Game Negative Declaration

and Forest Service Environmental Assessment outlined the proposed use of

rotenone without a final recovery plan in place. Response: There is no legal

requirement for a recovery plan to be finalized prior to the implementation of a

project which contributes to the recovery of a species. 

42. Comment: Service should be a part of a joint Environmental Impact

Statement/Environmental Impact Report. Response: The Forest Service and

California Department of Fish and Game are the primary action agencies and have

both completed their respective public environmental documentation and review.

43. Comment: How does removing fish from the historic range reduce the likelihood

of fish being transplanted from elsewhere, like downstream of Silver King

Canyon? Response: Currently, nonnative fish occur just below Llewellyn Falls.

From this location it would be relatively easy to move fish above the falls into

occupied habitat. Although the threat of reintroduction will always exist, it is

anticipated that this threat will be minimized if nonnative fish are removed because

they would have to be transported from below Silver King Canyon. This is a long

and treacherous canyon which should make it difficult to transport fish through the

canyon to Paiute cutthroat trout occupied habitat.

44. Comment: Water quality monitoring is inadequate. Response: The adequacy of

water quality monitoring has been analyzed through both the National

Environmental Policy Act process and section 7(a)(2) of the Endangered Species

Act. Additionally, the California Regional Water Quality Control Board,

Lahontan Region (LRWQCB) has reviewed the California Department of Fish and

Game’s proposal and found that the Basin Plan Objectives would be met

(LRWQCB July 3, 2003, letter to California Department of Fish and Game). 
C-13

45. Comment: Critical habitat has not been designated for the Paiute cutthroat trout

which is a required element under the Endangered Species Act. Response:

Pursuant to the 1978 amendment of the Endangered Species Act, we are required

to designate critical habitat in conjunction with the listing of a species if we find

critical habitat to be prudent and determinable. The original rule listing Paiute

cutthroat trout as endangered in 1967 did not address the prudency and

determinability of critical habitat, because these requirements were not in place at

that time. Our ability to designate critical habitat is also practically constrained by

availability of staff time and funding to do so. However, any decisions regarding

designation of critical habitat are separate and distinct from the process of

developing a recovery plan for the species.

46. Comment: It is illogical to state “genetic diversity could be subjected to

additional severe bottlenecks due to inadequate population size” given that Paiute

cutthroat trout evolved as a small population and now inhabit more stream miles

than it did historically. Response: Populations of Paiute cutthroat trout have gone

through severe bottlenecks since they first evolved from Lahontan cutthroat trout. 

The out-of-basin populations were created through the introduction of very few

individuals. The Paiute cutthroat trout does occupy more stream miles than it did

historically; however, they are all isolated and there is no gene flow between these

isolated populations.

47. Comment: There is common doubletalk about restoring genetically pure trout

species, where arbitrary standards of purity (usually 99-100 percent) are deemed

essential, while at the same time saying genetic diversity is just as essential. 

Response: Genetic purity and diversity are two separate yet equally important

components to recovery. Genetic purity refers to genes from nonnative species,

such as rainbow trout, being found within the population of Paiute cutthroat trout. 

If a fish has both Paiute cutthroat trout and rainbow trout genes it is no longer a

pure Paiute cutthroat trout but is referred as a hybrid. Genetic diversity refers to

the genetic variability of genes within the pure population of Paiute cutthroat trout

and is an important component to the long-term viability of the species. 

48. Comment: The fact that Paiute cutthroat trout were able to evolve, survive, and

thrive in 9 miles of stream brings into question the argument that it requires

restoration of hundreds and hundreds of stream miles to prevent the extinction of

other cutthroat trout species. Response: It is not within the scope of the Revised

Recovery Plan to address the recovery needs of other subspecies of cutthroat trout.

49. Comment: The U.S. Fish and Wildlife Service fails to acknowledge that our own

activities, such as stocking of nonnative trout and applying fish poisons, contribute

to extinction threats of Paiute cutthroat trout. Response: The stocking of
C-14

nonnative trout was identified as a threat factor in the listing of Paiute cutthroat

trout. Although stocking no longer occurs in Silver King Creek, recovery cannot

be achieved without removing the threat of nonnative fish.

50. Comment: The plan fails to acknowledge or analyze the potential effects of global

warming on Paiute cutthroat trout survival. Response: It is possible that climatic

change could affect habitat suitability for Paiute cutthroat trout in the future. 

However, at this time we are unable to predict the likelihood or significance of

such consequences with sufficient confidence to analyze their site-specific effects

on the species.

51. Comment: Was an Environmental Assessment completed for electrofishing

surveys which also harms fish and amphibians? Response: The California

Department of Fish and Game is responsible for the management of Paiute

cutthroat trout. Fisheries management, including electrofishing surveys, is subject

to the 4(d) provisions of the Endangered Species Act. 

52. Comment: The Plan states that “there should be no degradation of habitat from

existing conditions due to anthropogenic effects”. The U.S. Fish and Wildlife

Service seems to have a blind spot when it comes to recognizing that its own

activities degrade the environment and cause anthropogenic effects. Response:

The effects of the recovery actions were analyzed through the National

Environmental Policy Act and Endangered Species Act processes to determine if

these effects are significant and will result in an unacceptable level of adverse

impacts to the species. The analysis concluded that the level of impacts would not

preclude the recovery of the species.

53. Comment: The poisoning plan, restocking, and subsequent sport fishery offer no

new protections for Paiute cutthroat trout. Response: The removal of nonnatives

and subsequent restocking of Paiute cutthroat trout into their historic range will

significantly reduce the threat of competition and hybridization from nonnative

salmonids. In addition, increasing occupied habitat will reduce the threat of

stochastic events (such as fire or flooding) that may occur in the Silver King Creek

drainage. The California Department of Fish and Game is responsible for the

management of Paiute cutthroat trout. Any regulations relating to angling would

be subject to the 4(d) provisions of the Endangered Species Act and state laws and

regulations and would not be allowed until certain population criteria were met.

54. Comment: The third reason in the Draft Plan for action below Llewellyn Falls is

the risk of bottlenecks. These bottlenecks in Paiute cutthroat trout populations are

already present. Analysis of Paiute cutthroat trout genetic markers all concluded
C-15

that bottlenecks are present in the remaining populations (Israel et al. 2002,

Nielsen and Sage 2002). Response: The actions in the Revised Recovery Plan

seek to maximize the genetic diversity of existing populations (Recovery actions 

4.3, 4.3.4, 4.3.5, 4.4, 4.4.4, 4.4.5, 4.5, 4.5.4, 4.5.5) and to minimize the risks from

genetic bottlenecks that have occurred since Paiute cutthroat trout first evolved

from Lahontan cutthroat. 

55. Comment: There is confusion in the Draft Plan about hybrid crosses between

Paiute cutthroat trout and rainbow trout versus Paiute cutthroat trout and Lahontan

cutthroat trout. The Draft Plan states “genetic analysis indicates that Corral Valley

Creek now contains pure Paiute cutthroat trout (Israel et al. 2002).” But the Israel

et al. (2002) report states “None of the loci screened showed fixed differences

between Paiute cutthroat trout and Lahontan cutthroat trout.” And in summary it

states “Additionally, molecular markers that can distinguish Lahontan cutthroat

trout and Paiute cutthroat trout would provide another tool for determining this

relationship.” Clearly, the Israel et al. (2002) study did not separate Lahontan

cutthroat trout from Paiute cutthroat trout. Response: The term pure Paiute

cutthroat trout refers to the lack of rainbow trout genes. Other studies have

documented genetic differences between Paiute cutthroat trout and Lahontan

cutthroat trout (Nielson and Sage 2002). Further genetic testing is identified in the 

Revised Recovery Plan to clarify this issue (Recovery actions 4.3.2, 4.4.2, 4.5.2). 

56. Comment: The Israel et al. (2002) study even casts doubt on the genetic

separation of Paiute cutthroat trout from rainbow trout: “Upon examination of the

SCN evidence it does not appear that any population has undergone recent

hybridization with rainbow trout; however, introgression from past hybridization

events may be difficult to detect when relying on a single genetic marker.” 

Response: Israel et al. (2002) does not cast doubt on the genetic separation

between Paiute cutthroat trout and rainbow trout. Paiute cutthroat trout evolved

from Lahontan cutthroat trout. The quote is referring to the fact that one genetic

marker was used and that other markers should be explored. Further genetic

testing is identified in the Revised Recovery Plan (Recovery actions 4.3.2, 4.4.2,

4.5.2). Using the best available information, there is no evidence of hybridization

with rainbow trout in the existing Paiute cutthroat trout populations.

57. Comment: The discussion of fish abundances in Upper Fish Valley is confusing

and redundant with a later section (Draft Plan pg.3). Response: We agree, that

section has been removed from the plan.

58. Comment: If the purpose of citing the various numbers of fish is to build a case

for some needed number of fish, then the values presented are misleading. The

Draft Plan leaves it to the reader to add up miles of stream, numbers of fish per
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mile, mean number of fish, and locations. Response: The purpose of citing

various numbers of fish is to give the reader an idea of the size of the existing

populations and how they fluctuate from year to year, not to build a case for a

required number of fish. The values cited for recovery were taken from peer

reviewed literature (Hilderbrand and Kershner 2000) and may need to be revised

as additional information becomes available.

59. Comment: Without criteria for the meaning of stable, the goal is meaningless and

has little utility with a highly fluctuating population. There are enough data points

to consider that a population is stable if it is within +/- 2 standard deviations or the

95 % confidence interval of the long term mean. Response: Recovery Criterion 2

has been changed slightly and expanded upon to clarify our intentions.

60. Comment: In spite of the long time the U.S. Fish and Wildlife Service and

California Department of Fish and Game have been managing fish in the Silver

King Basin, nearly the only reported data on age and growth is from studies done

in the North Fork of Cottonwood Creek where Paiute cutthroat trout are

nonnatives. The U.S. Fish and Wildlife Service and California Department of Fish

and Game have no data on number of age classes, yet the U.S. Fish and Wildlife

Service has selected a rule for judging recovery based on age classes. Response: 

We based this recovery criterion on the best available information in the scientific

literature. As stated in the Revised Recovery Plan, the numbers and size of fish

required for recovery may need to be revised as additional information becomes

available.

61. Comment: The definition for a population of at least 2,500 fish > 75mm in

length, has not been separately reported for any population in the Silver King

drainage, and no rationale has been presented for its choice. There is

inconsistency with the size of adult fish. Adult fish are defined as > 150 mm in

Silver King Creek and >137 mm in Stairway Creek. Which is it? Response: The

rationale for the selection of this value was taken from peer reviewed literature

(Hilderbrand and Kershner 2000) and may need to be revised as additional

information becomes available. Adult fish are defined using various sizes because

they grow at different rates in the separate drainages in which they exist. 

62. Comment: It is difficult to tell if the U.S. Fish and Wildlife Service population

goal of at least 2,500 fish applies to the total of the separate populations in the

Silver King drainage or to each of the separate populations. Response: The goal

is to have 2,500 fish greater than 75 mm in length occupying the historic range

from Llewellyn Falls downstream to Silver King Canyon. As stated in the Revised

Recovery Plan, this number is a preliminary estimate and may be revised as

additional information becomes available.
C-17

63. Comment: The lack of any habitat condition assessment for the last 14 years

belies any genuine agency interest in this subspecies. Habitat was a key criterion

to recovery of the Paiute cutthroat trout (“Habitat and population trends will be

closely monitored” 1985 Plan). But even this critical management goal seems to

have been abandoned. Response: Habitat was monitored in 1984, 1987, and 1990

(Table 3, Revised Recovery Plan). Nonnative fish removal and subsequent

reintroduction of Paiute cutthroat trout into Silver King Creek above Llewellyn

Falls in the 1990’s took priority over habitat monitoring due to budget and staffing

limitations. Habitat monitoring is an important component of the recovery actions

for Paiute cutthroat trout (Recovery criterion 3). 

64. Comment: “The primary threat to Paiute cutthroat trout is hybridization with

nonnative trout” (Draft Plan p.49). That threat will remain no matter how large an

area the Paiute cutthroat trout occupies. Response: We agree that this threat will

always remain, however, through education and the removal of nonnative fish

throughout its historic range, we believe this threat can be minimized to a level

that will allow for a viable population of Paiute cutthroat trout throughout its

historic range (Recovery action #6).

65. Comment: The Draft Plan does not recognize that a threatened trout species

outside its native habitat is a nonnative species and has as much an impact as any

other nonnative species. Response: We agree that any species outside its native

habitat can be considered a nonnative species. Amphibian monitoring will

continue in occupied habitat outside of Paiute cutthroat trout historic habitat to

evaluate and address any adverse impacts of Paiute cutthroat trout to amphibian

species. 

66. Comment: The apparent lack of baseline information makes it difficult to assess

the impacts of past, current, and proposed recovery efforts; the gathering of such

information should be a priority. Data needs to be developed to demonstrate that

physical, chemical, and biological processes are examined and interactions in the

Silver King Creek drainage are understood. Response: Ongoing data collection

will continue for the purposes of recovery of Paiute cutthroat trout. Data

collection will include but will not be limited to water quality, macroinvertebrates,

amphibians, riparian and stream habitat quantity and quality, and Paiute cutthroat

trout population dynamics.

67. Comment: Various predictions of success appear unrealistic given that four

decades of fish removal activities were needed to eliminate introduced trout from

upper portions of Silver King Creek drainage, that no systematic assessment as to

the ecosystem impacts of these previous treatments has occurred (nor is proposed),

that project proposals do not even concede the possibility of cumulative impacts
C-18

within Silver King Creek drainage from past and ongoing poisonings, and that the

measure of success to date has been limited to the removal of all fish and the

reestablishment of genetically pure Paiute cutthroat trout rather than the recovery

of the Paiute cutthroat trout and the physical, biological, and chemical

functionality of its habitat. Response: Recovery plans must address the known

threats to the species which may include threats to the genetic viability of the

species as well as the habitat which supports it. We believe the Revised Recovery

Plan provides a multifaceted approach which addresses the various threats to this

species. The cumulative impacts of any recovery action is addressed through

separate processes including those relating to the National Environmental Policy

Act and the Endangered Species Act.

68. Comment: The Plan fails to establish metrics of land use pattern and practice

(e.g., quantitative and qualitative standards, guidelines, and goals) and for

watershed condition that corresponds with maintenance and recovery of habitat

condition sufficient for persistence of Paiute cutthroat trout and other at-risk

species within the Silver King Creek drainage. Response: The primary threat to

Paiute cutthroat trout habitat in the Silver King Creek drainage has been the

destruction and degradation of habitat through improper livestock grazing

management. Grazing has not been allowed since 1995 and the habitat condition

has improved dramatically. It is anticipated that the allotment will remain closed

to grazing and the habitat will continue to improve which will benefit both Paiute

cutthroat trout and other at-risk species such as the mountain yellow-legged frog

and Yosemite toad. This supports Recovery Criterion 3, which requires no

degradation of habitat from existing conditions due to anthropogenic effects.

69. Comment: The Plan should identify specific variables to describe habitat

condition, including threshold criteria for suitable and high quality habitat. 

Response: Recovery Action 3.1.1. requires the institution of a stream and riparian

habitat monitoring program which uses an established stream monitoring protocol

with measurable and repeatable methods. Most of the currently occupied and

historic Paiute cutthroat trout habitat is in relatively good condition. The Revised

Recovery Plan states that habitat should have no degradation from existing

conditions due to anthropogenic effects.

70. Comment: The Plan does not emphasize ecosystem recovery. Response: We

believe the Revised Recovery Plan does emphasize ecosystem recovery by the

continued rest from livestock grazing, the eradication of nonnative salmonids and

subsequent repatriation of Paiute cutthroat trout, and keeping the high elevation

lakes in the drainage fishless for the benefit of the mountain yellow-legged frog

and Yosemite toad.