Distribution and Movement of Bull Trout in the 

Upper Jarbidge River Watershed, Nevada

Open-File Report 2010-1033

Prepared in cooperation with the U.S. Fish and Wildlife Service

U.S. Department of the Interior

U.S. Geological Survey

Distribution and Movement of Bull Trout in the Upper 

Jarbidge River Watershed, Nevada 

By M. Brady Allen, Patrick J. Connolly, Matthew G. Mesa, Jodi Charrier, and Chris Dixon 

Prepared in cooperation with the U.S. Fish and Wildlife Service 

Open-File Report 2010–1033 

U.S. Department of the Interior 

U.S. Geological Survey 
U.S. Department of the Interior 

KEN SALAZAR, Secretary 

U.S. Geological Survey 

Marcia K. McNutt, Director 

U.S. Geological Survey, Reston, Virginia: 2010 

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Suggested citation: 

Allen, M.B., Connolly, P.J., Mesa, M.G., Charrier, Jodi, and Dixon, Chris, 2010, Distribution and 

movement of bull trout in the upper Jarbidge River watershed, Nevada: U.S. Geological Survey 

Open-File Report 2010-1033, 80 p. 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government. 

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report. 
Contents 

Abstract ......................................................................................................................................................... 1

Introduction.................................................................................................................................................... 2

Description of Study Site ............................................................................................................................... 2

Study Methods............................................................................................................................................... 3

Fish Collection and Tagging....................................................................................................................... 3

Habitat Sampling........................................................................................................................................ 4

PIT Tag Interrogation Systems .................................................................................................................. 5

Data Reconciliation and Analysis............................................................................................................... 5

Results of Surveys......................................................................................................................................... 6

West Fork Jarbidge River watershed ......................................................................................................... 7

East Fork Jarbidge River Watershed ......................................................................................................... 9

Overall Distribution and Abundance of Bull Trout in Jack Creek.............................................................. 12

Movements of Bull Trout .......................................................................................................................... 13

Distribution, Growth, and Movement of Bull Trout ....................................................................................... 14

General Catch Information and Population Characteristics...................................................................... 15

Movement of Bull Trout............................................................................................................................ 17

Conclusions, Summary, and Recommendations ......................................................................................... 20

Acknowledgments ....................................................................................................................................... 21

References .................................................................................................................................................. 21

Appendix table and figures .......................................................................................................................... 64

Figures 

Figure 1. Map of the East and West Forks of the Jarbidge River, Idaho and Nevada, with the 

locations of reported fish barriers and passive integrated transponder (PIT) tag interrogations 

systems installed in 2006 or 2007. .............................................................................................................. 25

Figure 2. Locations of fish and habitat surveys, fish barriers, and passive integrated transponder 

(PIT) tag interrogation systems in the West Fork Jarbidge River, Nevada, and its tributaries, 2006 

and 2007...................................................................................................................................................... 26

Figure 3. Locations of fish and habitat surveys, fish barriers, and passive integrated transponder 

(PIT) tag interrogation systems in the East Fork Jarbidge River, Nevada, and its tributaries, 

2006 and 2007............................................................................................................................................. 27

Figure 4. Length frequency, in 2-mm increments, of all bull trout sampled in the West Fork 

Jarbidge River, Nevada, in 2006 and 2007.................................................................................................. 28

Figure 5. The number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in West Fork Jarbidge River (rkm 21.5 – 30.2), Nevada, 2006 .... 29

Figure 6. Number of bull trout (BLT) per meter by size class for all habitat units sampled along 

with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter by size 

class in pools only (lower graph) in West Fork Jarbidge River (rkm 21.7 – 32.2), Nevada, 2007 ................ 30

Figure 7. Length frequency ,in 2-mm increments, of all bull trout sampled in Pine Creek of the 

West Fork Jarbidge River subbasin, Nevada in 2006 and 2007 .................................................................. 31

Figure 8. Number of bull trout (BLT) per meter by size class for all habitat units sampled along 

with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter by size 

class in pools only (lower graph) in Pine Creek (rkm 0 – 6.5), Nevada, 2006.............................................. 32

iii 
Figure 9. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Pine Creek (rkm 0 – 5.9), Nevada, 2007.................................. 33

Figure 10. Length frequency in 2-mm increments of all bull trout sampled in Jack Creek of the 

West Fork Jarbidge River, Nevada, in 2006 and 2007 ................................................................................ 34

Figure 11. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Jack Creek (rkm 0 – 4.3), Nevada, 2006 ................................. 35

Figure 12. Number of bull trout (BLT) per meter, by size class, for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Jack Creek (rkm 0 – 5.4), Nevada, 2007 ................................. 36

Figure 13. Length frequency in 2-mm increments of all bull trout sampled in the East Fork 

Jarbidge River, Nevada, in 2006 and 2007. Sampling effort is not the same for each year......................... 37

Figure 14. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in East Fork Jarbidge River (rkm 15.6 – 24.7), Nevada, 

2006 ............................................................................................................................................................ 38

Figure 15. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in East Fork Jarbidge River (rkm 32.5 – 35.0), Nevada, 2007 ..... 39

Figure 16. Length frequency in 2-mm increments of all bull trout sampled in Cougar Creek, 

Nevada, and an unnamed tributary of the East Fork Jarbidge River, Nevada, at rkm 33.5 

(measured from the confluence with the West Fork Jarbidge River, Idaho), 2007....................................... 40

Figure 17. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Cougar Creek (rkm 0 – 3.1), Nevada, 2007 ............................. 41

Figure 18. Length frequency in 2-mm increments of all bull trout sampled in Fall Creek of the 

East Fork Jarbidge River, Nevada, in 2006 and 2007 ................................................................................. 42

Figure 19. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Fall Creek (rkm 0 – 2.0), Nevada, 2006 ................................... 43

Figure 20. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Fall Creek (rkm 1.4 – 3.2), Nevada, 2007. ............................... 44

Figure 21. Length frequency in 2-mm increments of all bull trout sampled in Slide Creek of the 

East Fork Jarbidge River, Nevada, in 2006 and 2007. Sampling effort is not the same for each year ........ 45

Figure 22. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Slide Creek (rkm 0 – 5.5), Nevada, 2006................................. 46

Figure 23. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Slide Creek (rkm 4.6 – 7.7), Nevada, 2007.............................. 47

Figure 24. Length frequency in 2-mm increments of all bull trout sampled in Dave Creek of the 

East Fork Jarbidge River, Nevada, in summer 2006, early summer 2007, and late summer 2007 ............. 48

Figure 25. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Dave Creek (rkm 6.8 – 11.7), Nevada, 2006 ........................... 49

iv 
Figure 26. Number of bull trout (BLT) per meter by size class for all habitat units sampled 

along with altitude (upper graph) and the number of bull trout and redband trout (RBT) per meter 

by size class in pools only (lower graph) in Dave Creek (rkm 6.8 – 14.0), Nevada, 2007. .......................... 50

Figure 27. Operational status of interrogation systems during 2007 in the Jarbidge River subbasin, 

Idaho and Nevada ....................................................................................................................................... 51

Figure 28. Number and movement direction of PIT tagged bull trout by month detected at the 

interrogation site in the East Fork Jarbidge River (EFJ, rkm 4.1), Idaho, and at the East Fork 

Jarbidge River and West Fork Jarbidge River (Forks, rkm 0.1) interrogation sites, Idaho, during 2007 ...... 52

Figure 29. Streamflow (cfs), temperature, and direction of PIT tagged bull trout movements 

detected at interrogation sites in West Fork Jarbidge River (rkm 15), Jack Creek (rkm 0.1), and 

West Fork Jarbidge and Pine Creek confluence (rkm 26), Nevada, 2007 ................................................... 53

Figure 30. Time of day that PIT tagged bull trout passed any interrogation system in the Jarbidge 

River subbasin, Idaho and Nevada, in 2006 and 2007 ................................................................................ 54

Tables 

Table 1. Number of bull trout the captured by electrofishing and PIT tagged in the East and 

West Forks of the Jarbidge River watershed in 2006 .................................................................................. 55

Table 2. Number of bull trout captured by electrofishing and PIT tagged in the West Fork 

Jarbidge River subbasin in 2007 ................................................................................................................. 56

Table 3. Number of bull trout captured by electrofishing and PIT tagged in the East Fork 

Jarbidge River subbasin in 2007 ................................................................................................................. 57

Table 4. Location, altitude and estimated length of fish and habitat surveys conducted in the 

Jarbidge River watershed during 2006 ........................................................................................................ 58

Table 5. Location, altitude and estimated length of fish and habitat surveys conducted in the 

Jarbidge River watershed during 2007 ........................................................................................................ 59

Table 6. Number (n) of bull trout captured, the sampling distance (rkm), the number of bull 

trout captured with a fork length greater than 200 mm, the number of bull trout with a fork 

length greater than 250 mm, the minimum (min) fork length, the maximum (max) fork length, 

and weight of bull trout for each creek sampled in the Jarbidge River watershed, Nevada, in 

2006-2007 ................................................................................................................................................... 60

Table 7. Number (n) of bull trout (BLT) collected, survey length, percent of stream length with 

bull trout, the percent of habitat units with at least one bull trout, the percent of stream length 

that was pool-like, and percent of bull trout found in pools in the Jarbidge River watershed 

in 2006-2007................................................................................................................................................ 61

Table 8. Location and installation date of passive integrated transponder (PIT) tag interrogation 

units installed in the Jarbidge River watershed in 2006-2007, and the number of bull trout (BLT) 

interrogated by tagging location in 2006-2007............................................................................................. 62

Table 9. Stream discharge in the Jarbidge River watershed on sampling dates in 2007 ............................ 63

v 
vi 

Conversion Factors and Datums 

Conversion Factors 

Multiply By To obtain 

centimeter (cm) 0.3937 inch (in.) 

millimeter (mm) 0.03937 inch (in.) 

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi) 

square kilometer (km2

) 0.3861 square mile (mi2) 

gram (g) 0.03527 ounce, avoirdupois (oz) 

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows: 

°F=(1.8×°C)+32 

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows: 

°C=(°F-32)/1.8 

Datums 

Horizontal coordinate information is referenced to the World Geodetic System of 1984 (WGS84) datum. 

Vertical coordinate information is referenced to the WGS84 EGM96 geoid. 

Altitude, as used in this report, refers to distance above the vertical datum. 
Distribution and Movement of Bull Trout in the Upper 

Jarbidge River Watershed, Nevada 

By M. Brady Allen, Patrick J. Connolly, Matthew G. Mesa, Jodi Charrier, and Chris Dixon 

Abstract 

In 2006 and 2007, we surveyed the occurrence of bull trout (Salvelinus confluentus), the 

relative distributions of bull trout and redband trout (Oncorhynchus mykiss), and stream habitat 

conditions in the East and West Forks of the Jarbidge River in northeastern Nevada and southern 

Idaho. We installed passive integrated transponder (PIT) tag interrogation systems at strategic 

locations within the watershed, and PIT-tagged bull trout were monitored to evaluate individual 

fish growth, movement, and the connectivity of bull trout between streams. Robust bull trout 

populations were found in the upper portions of the East Fork Jarbidge River, the West Fork 

Jarbidge River, and in the Pine, Jack, Dave, and Fall Creeks. Small numbers of bull trout also 

were found in Slide and Cougar Creeks. Bull trout were numerically dominant in the upper 

portions of the East Fork Jarbidge River, and in Fall, Dave, Jack, and Pine Creeks, whereas 

redband trout were numerically dominant throughout the rest of the watershed. The relative 

abundance of bull trout was notably higher at altitudes above 2,100 m. 

 This study was successful in documenting bull trout population connectivity within the 

West Fork Jarbidge River, particularly between West Fork Jarbidge River and Pine Creek. 

Downstream movement of bull trout to the confluence of the East Fork and West Fork Jarbidge 

River both from Jack Creek (rkm 16.6) in the West Fork Jarbidge River and from Dave Creek 

(rkm 7.5) in the East Fork Jarbidge River was detected. Although bull trout exhibited some 

downstream movement during the spring and summer, much of their emigration occurred in the 

autumn, concurrent with decreasing water temperatures and slightly increasing flows. The bull 

trout that emigrated were mostly age-2 or older, but some age-1 fish also emigrated. Upstream 

movement by bull trout was detected less than downstream movement. The overall mean annual 

growth rate of bull trout in the East Fork and West Fork Jarbidge River was 36 mm. This growth 

rate is within the range reported in other river systems and is indicative of good habitat 

conditions. Mark-recapture methods were used to estimate a population of 147 age-1 or older 

bull trout in the reach of Jack Creek upstream of Jenny Creek. 

1 
Introduction 

The Jarbidge River population of bull trout (Salvelinus confluentus) was listed as 

threatened under the Endangered Species Act on April 8, 1999 (64 Federal Register 17110). Bull 

trout within the Jarbidge River are presumably limited to a single core area within the upper 

watershed, which comprises six local populations: (1) East Fork Jarbidge River (including the 

East Fork headwaters, Cougar Creek, and Fall Creek); (2) West Fork Jarbidge River (including 

Sawmill Creek); (3) Dave Creek; (4) Jack Creek; (5) Pine Creek; and (6) Slide Creek (U.S. Fish 

and Wildlife Service, 2004). Bull trout populations in these areas are thought to be mostly local, 

with few migratory (fluvial) fish present. In 2004, the Jarbidge River Bull Trout Recovery Team 

estimated that fewer than 500 bull trout, with 50–125 reproductively mature fish, were present 

within the core area (U.S. Fish and Wildlife Service, 2004). Several factors are suspected to have 

limited the Jarbidge River bull trout population historically, including livestock grazing, elevated 

water temperatures, road construction and maintenance, mining, and hatchery supplementation 

of rainbow trout (Oncorhynchus mykiss) (U.S. Fish and Wildlife Service, 2004). Stocking of 

hatchery rainbow trout was suspended in 1998. 

In 2006, the U.S. Fish and Wildlife Service (USFWS) formed a cooperative agreement 

with the U.S. Geological Survey’s (USGS) Columbia River Research Laboratory (CRRL) for 

USGS to collect information on the life history, movements, abundance, and distribution of bull 

trout in the upper Jarbidge River basin. This information was needed to assist managers in 

making informed decisions regarding bull trout recovery. The objectives of the resulting study 

were to: (1) monitor the movements, distribution, and growth of bull trout in selected tributaries 

of the Jarbidge River basin; (2) estimate the abundance of selected local bull trout populations; 

(3) conduct habitat surveys and assess habitat conditions; and (4) use the data collected as a 

baseline to develop a cost-effective monitoring strategy to assess population trends over time 

until recovery is achieved. The USGS investigators regularly coordinated with the Jarbidge River 

Bull Trout Recovery Team, which comprises staff members from the Idaho Department of 

Environmental Quality, Bureau of Land Management (BLM), Nevada Department of Wildlife 

(NDOW), the U.S. Forest Service (USFS), USFWS, and Idaho Department of Fish and Game. 

This report summarizes study findings from 2006 and 2007. 

Description of Study Site 

The headwaters of the Jarbidge River are in the Jarbidge Mountains of northeastern 

Nevada. The watershed is characterized by an elevated volcanic plateau that gradually slopes 

northward to the Snake River Plain, which drains approximately 1,264 km2

 (488 mi2; U.S. Fish 

and Wildlife Service, 2004). The upper watershed has a mountainous north-south crest with eight 

peaks greater than 3,050 m (10,000 ft) high. The East Fork and West Fork of the Jarbidge River 

flow northward for about 36 and 32 km, respectively, and merge about 6.4 km downstream of 

the Idaho-Nevada border. This confluence of the two forks was the downstream extent of our 

study area (fig. 1). The mainstem Jarbidge River continues another 45 km northwest and 

eventually empties into the Bruneau River in Idaho. Riparian vegetation in the watershed 

consists of juniper (Juniperus spp.), black cottonwood (Populus balsamifera), subalpine fir 

(Abies lasiocarpa), aspen (Populus tremuloides), and various forbs, grasses, and sedges (U.S. 

Fish and Wildlife Service, 2004). The Jarbidge Mountains have a subalpine climate and receive 

substantial amounts of precipitation, primarily in the form of snow, which is the major source of 

2
water for streams in the basin. Additional precipitation falls as rain during thunderstorms. Runoff 

follows the natural hydrograph, with high spring and early summer flows that diminish in the late 

summer but increase slightly during fall and winter. The only streamgaging station in the 

watershed is within our study area on the West Fork Jarbidge River downstream of Jarbidge, 

Nevada (USGS station number 13162225). 

Study Methods 

Fish Collection and Tagging 

We sampled all streams within the Jarbidge River basin known to contain bull trout as 

identified by the Jarbidge River Bull Trout Recovery Team. These included parts of the East 

Fork and West Fork Jarbidge River, and Cougar, Fall, Slide, Dave, Jack, and Pine Creeks (figs. 2 

and 3; tables 1, 2, and 3). In an attempt to find other streams containing bull trout, we conducted 

exploratory sampling in selected reaches of Deer, Buck, Sawmill, and God’s Pocket Creeks, and 

on an unnamed tributary of the East Fork Jarbidge River. Successive samples were collected in 

an upstream direction with the goal of reaching the end of fish distribution while tagging as 

many bull trout as possible of the appropriate size. In several streams, some sections were 

skipped in an effort to sample reaches with higher bull trout densities, which maximized the 

returns of the effort given the time allotted. The upper end of fish distribution was confirmed by 

electrofishing upstream of the likely barrier for approximately 100 m where practicable. 

Bull trout samples were collected using a Smith-Root model 15-B backpack electrofisher 

equipped with one small probe and one “rat tail” electrode. Each stream reach was electrofished 

in a single upstream pass and all habitats likely to contain bull trout were sampled. All observed 

bull trout were captured. Redband trout were not captured, but were enumerated and generally 

classified as being less than 80 mm, 80 to 150 mm, or larger than 150 mm in pools only. The 

occurrence of redband trout in pools was recorded to indicate their general abundance without 

overly slowing the progress of the sampling crew that would have resulted if redband trout had 

been counted and classified in the much longer non-pool sections as well. The general abundance 

of other fish species was noted as rare, present, or highly abundant. All captured bull trout were 

anesthetized with a 50-mg/L solution of tricaine methanesulfonate (MS-222), measured fork 

length to the nearest millimeter, weighed to the nearest 0.1 g, and inspected for reproductive 

status and external signs of disease or injury. 

We tagged bull trout using full-duplex SGL model passive integrated transponder (PIT) 

tags (manufactured by Biomark, Inc., Boise, Idaho) that were 12 mm in length and operated at a 

frequency of 134.2 kHz. Fish less than 70 mm were considered too small to tag. In fish between 

70 and 120 mm long, tags were injected into the peritoneal cavity. Fish greater than 120 mm 

were tagged in the dorsal sinus to minimize the potential for shedding of tags during spawning. 

A sample of caudal fin tissue was removed from most bull trout, placed in a pre-labeled vial 

containing 2 mL of 100% non-denatured ethanol, and sent to the USFWS’s Abernathy Fish 

Technology Center (Longview, Wash.) for genetic analysis as part of a separate, but coordinated 

study (De Haan and others, 2007). Where bull trout were locally abundant, a genetic sample was 

taken from a subset of bull trout; otherwise a genetic sample was collected from each fish. After 

they recovered from the effects of tagging, fish were released in the location of capture. 

3
In 2007, we conducted a Petersen mark-recapture population estimate for bull trout in 

Jack Creek. To facilitate repeatability, Jack Creek was selected because of ease of access and the 

known presence of a bull trout population. The population was estimated in two sections of Jack 

Creek: from the confluence with West Fork Jarbidge River upstream to the confluence of Jenny 

Creek (rkm 1.8); and upstream of Jenny Creek to the end of fish distribution (rkm 5.4). Three 

block nets and a picket weir were placed consecutively at the downstream end of each section to 

ensure a closed population. We electrofished the sections in one slow, methodical upstream pass, 

each within 1 day. In both the 3.6 km section upstream of Jenny Creek and the 1.8 km section 

downstream, three people started at the block nets on the downstream end, and three others 

started at the mid point. Only bull trout longer than 80 mm (age-1 or older) were included in the 

estimate. We tagged all captured bull trout, and the recapture effort occurred 24-30 h later. 

Habitat Sampling 

Along with electrofishing, we conducted habitat surveys using the classification system 

described by Bisson and others (2006), which is a modification of an earlier hierarchical 

subdivision of channel units by Hawkins and others (1993). Using this system, we classified 

habitat units into pools and non-pools. We conducted daily visual distance calibrations for 

personnel with a measuring tape. On the basis of these visual estimates, we recorded the length 

and width of each habitat unit. We also measured maximum and mean water depths, and visually 

estimated the percent total instream and overhead cover by cover type (for example, large and 

small wood, substrate, and undercut bank), and percent riparian shade provided by trees and 

shrubs. Global positioning system (GPS) location coordinates and altitudes were recorded at the 

beginning and end of the survey each day. Stream temperature data were collected with a 

handheld thermometer at all electrofishing sites — in the morning, at mid-day, and in the 

afternoon (appendix table A1) — to ensure that temperatures were appropriate for electrofishing 

or PIT tagging. Because of the high variability of water temperatures measured with handheld 

thermometers, owing to the time of year, time of day, weather, and proximity to springs, among 

other factors, this temperature information was not used in the analysis, but is provided in the 

appendix. Stream temperatures also were recorded by the BLM via a network of automated 

thermographs placed at various sites throughout the East and West Forks Jarbidge Rivers; this 

temperature information was used in the analysis. 

Seven streamflow monitoring stations were established near the PIT tag interrogation 

system (PTIS) sites for the purposes of this study. Stream discharge measurements were made at 

each of these stations three times in August 2007 to assess tributary contributions to overall flow. 

Following the protocol of Bain and Stevenson (1999), we anchored a measuring tape 

perpendicular to streamflow and recorded the distance to the left and right wetted edge. We 

measured water depth and velocity with a Marsh-McBirney model 2000 flow meter at a 

minimum of 10 (although usually at about 20) intervals along the measuring tape. Because water 

depths were always less than 1 m, water velocities were measured at 60% of the depth at each 

interval. 

4
PIT Tag Interrogation Systems 

On September 15, 2006, we installed instream PTISs at three locations: at the mouth of 

Jack Creek; in West Fork Jarbidge River about 2.4 km downstream of Jack Creek; and in East 

Fork Jarbidge River near the town of Murphy Hot Springs, Idaho (fig. 1). At Jack Creek, one PIT 

tag transceiver (model FS2001F-ISO, Digital Angel, St. Paul, MN, USA) with a single custom 

antenna was installed. This site was powered by one 12-volt battery, which was trickle-charged 

by a solar panel. On the West Fork Jarbidge River, we installed two stream-width, pass-by 

antennas connected to a multiplexing transceiver (model FS1001M (MUX), Digital Angel, St. 

Paul, Minn., USA). The transceiver was powered by four 12-volt batteries, which were tricklecharged by two solar panels. The design of the PTIS in the East Fork Jarbidge River was similar 

to that in the West Fork Jarbidge River, but with two arrays of two pass-through antennas 

installed. The multiple-antenna design system, which was used and is described by Connolly and 

others (2005), was expected to provide high detection efficiencies; however, the systems 

installed for this project had two arrays instead of three, which would reduce the detection 

efficiencies as well as the ability to calculate them (Connolly and others, 2008). Data from the 

PTISs were downloaded and the batteries were changed once a week from September through 

December 2006, after which the equipment was removed for the winter. 

In 2007, six PTISs were installed, three at the pre-established (in 2006) sites and three at 

new sites. On April 28, 2007, the three PTISs described above were reinstalled (fig. 1). In Dave 

Creek, on May 23, 2007, at about rkm 0.4, a single-antenna PTIS was installed similar to the one 

in Jack Creek. In the West Fork Jarbidge River, a MUX-style PTIS was installed on July 16, 

2007, at the confluence of Pine Creek (rkm 26.2), with two stream-width antennas in Pine Creek 

and two in the West Fork Jarbidge River just downstream of the confluence. At the confluence of 

the East Fork and West Fork Jarbidge River (“the Forks”), another PTIS was installed on July 

17, 2007. This system was comprised of two stream-width antennas in both the East Fork and 

West Fork Jarbidge River. To prevent damage to the PTIS equipment during winter, the units 

were removed from all sites on December 19, 2007. In general, the PTISs were strategically 

placed to investigate the potential linkage between local populations of fish throughout the 

watershed. In both years, the systems were tested with a test tag when battery exchanges or data 

downloading occurred. 

Data Reconciliation and Analysis 

Detections of PIT tagged fish were merged with tagging data. We used independent 

reconciliation of PIT tag records by two biologists to classify movements as upstream, 

downstream, or of unknown direction. The time and location of tagging and other interrogation 

events were used to determine the direction of fish movements. If multiple interrogation events 

of the same fish occurred within 2 days, they were considered to be one movement event. 

Directional fish movement events were accepted when there was consensus on the direction of 

movement by the two biologists. If discrepancies in assigning direction could not be reconciled, 

the movement was recorded as an unknown direction. The operational run times for the systems 

were determined using the buffer data (see below) and the field log notebooks of the PTIS units. 

The buffer data provided records of the dates and times that each interrogation system was 

running. Additional information was obtained by reviewing the field notes, which were recorded 

during downloading. 

5
Recaptured bull trout were used to calculate information on movement and growth rates. 

Annual growth rates were calculated for all recaptured fish with more than 320 days between 

tagging and recapture. Because the number of days between tagging and recapture varied among 

individuals and between fish in different streams, the annual growth rate was standardized to a 

full year by dividing the change in length by the fraction of the year between capture and 

recapture. We conducted length frequency analysis to determine fish age at length for age-0 to 

age-2 bull trout. The length frequency histograms exhibit distinct modes of the first few age 

classes, which can provide insight into annual growth rates. The growth rate from length 

frequency analysis was validated with growth rates calculated via recaptured PIT tagged fish. 

For our mark recapture study, we estimated the number of bull trout in two sections of 

Jack Creek as follows: 

 N = [(M + 1)*(C + 1)/ R + 1] – 1, (1) 

where M = number of fish marked on the first sample, C = number of fish captured in the second 

sample, and R = number of fish with a mark captured in the second sample. The confidence 

interval for each estimate was calculated using a binomial distribution when R/C was greater 

than 0.10 (Seber, 1982). 

To estimate discharge at our streamflow monitoring stations, flow was computed by 

summing the flows of intervals, where the flow at each interval was calculated using the 

equation: 

n

nn

nn v

bb dQ 



 



   

2

11 , (2) 

where = discharge at interval n, = water depth at interval n, = distance along the tape 

measure from the left wetted edge to point n, and = mean velocity in interval n. 

Qn dn bn

n v

Results of Surveys 

From July 19 to October 4, 2006, we sampled a total of 39.9 km of stream channel in 

reaches of East Fork and West Fork Jarbidge River, and in Fall, Slide, Dave, Jack, and Pine 

Creeks (figs. 2 and 3). A total of 349 bull trout were captured, of which 322 were PIT tagged and 

237 were fin clipped for genetic analysis by the USFWS (table 1). The majority (84%) of fish 

were PIT tagged in Dave Creek, West Fork Jarbidge River, and Jack Creek. We collected only a 

few age-0 bull trout — three in upper Jack Creek, two in upper West Fork Jarbidge River, and 

one in Pine Creek. Sampling ended because of observed spawning activity by fish in Dave 

(August 6), Slide (August 22), and Jack (September 11) Creeks. We observed no direct bull trout 

mortalities during sampling in 2006. 

From June 13 to September 14, 2007, we sampled 24.9 km of stream channel in the West 

Fork Jarbidge River and its tributaries, and 18 km of stream channel in the East Fork Jarbidge 

River and its tributaries (tables 2 and 3). The total lengths of stream sampled and latitude and 

longitude of the start and end points are shown in tables 4 and 5. In 2007, 1,353 bull trout were 

captured, of which 1,214 were PIT tagged, and 569 were fin clipped for genetic analysis (tables 2 

and 3). The majority (88%) of bull trout were PIT tagged in upper East Fork Jarbidge River, 

upper West Fork Jarbidge River, and Dave, Pine, and Jack Creeks. We collected substantially 

more age-0 fish in 2007 than in 2006 — four fish in upper Dave Creek, 41 fish in Jack Creek, 

6
36 fish in Pine Creek, and a single 28-mm bull trout collected on June 22, 2007, in the upper 

West Fork Jarbidge River. Three fish died as a consequence of electrofishing (direct mortality) in 

2007, which was 0.2% of the total number of bull trout handled. 

In addition to bull trout, redband trout, sculpin (Cottus spp.), and mountain whitefish 

(Prosopium williamsoni) were commonly encountered during sampling. In 2006, in the lower 

East Fork Jarbidge River just upstream of Murphy Hot Springs, we also encountered dace 

(Rhinichthys spp.), bridgelip sucker (Catostomus columbianus), and redside shiner 

(Richardsonius balteatus). We found no evidence of disease or introgression (vermiculation and 

pigment on the dorsal fin) with brook trout (Salvelinus fontinalis) in any of the bull trout we 

captured. 

West Fork Jarbidge River watershed 

West Fork Jarbidge River.—In 2006, one bull trout was captured near the West Fork 

Jarbidge River antenna site (rkm 14.5–15.5), and 96 fish were captured between rkm 22.0–30.0 

(table 1). Sampling was stopped 1.3 km downstream of the end of fish distribution (as 

determined in 2007) due to time constraints. In 2007, sampling started at the first bridge 

upstream of the town of Jarbidge (rkm 21.7) and ended at rkm 32.2, 100 m upstream of a 1.3-m 

barrier falls, which was the uppermost point of fish distribution, as indicated by our sampling. 

We also sampled about a 100-m long reach of Sawmill Creek (which contributed 25% of the 

total West Fork Jarbidge River flow) and captured one redband trout and no bull trout. Several 

temporary, naturally formed low-flow fish barriers (substrate and wood) were present in West 

Fork Jarbidge River in 2007, with the most downstream barrier about 1.5 km upstream of the 

confluence with Pine Creek. In 2007, 272 bull trout were captured between rkm 21.7 and 32.2 

(table 2, fig. 2). For both years, the minimum fork length was 23 mm, and the maximum was 330 

mm (table 6). Most of the bull trout were age-1 and age-2, with relatively few fish longer than 

200 mm (11% of our catch in 2006, 7% in 2007; table 6, fig. 4). 

In 2007, we recaptured six bull trout that were originally PIT tagged in July and August 

2006. The mean annual growth rate of these fish was 32 mm (range = 8-39 mm; SD = 4.8; fig. 

4). The length of these fish at tagging ranged from 90 to 185 mm. Using length-frequency 

analysis, we estimated age-1 bull trout to be between 83 and 115 mm and age-2 fish to be longer 

than 120 mm in late July and early August 2006. In June 2007, age-1 bull trout were between 70 

and 115 mm, and age-2 fish were from 120 to about 160 mm. 

In both years, bull trout were found primarily at altitudes above 2,100 m and in greater 

abundance at increasingly greater altitudes (figs. 5 and 6). Redband trout were found throughout 

the area we sampled, but with reduced abundances as altitude increased. In 2006, bull trout 

longer than 200 mm were more common in the lower altitude reaches than in the higher reaches, 

but they were more evenly distributed in 2007. We sampled earlier in 2007 (June–July) than in 

2006 (July–September), which could account for the differences in fish distribution. We sampled 

earlier in the year in 2007 because we encountered spawning activity during our sampling in 

2006. A single age-0 bull trout was collected in the West Fork Jarbidge River in each year (figs. 

4, 5, and 6). These fish were collected in the uppermost reaches, at altitudes greater than 2,100 m 

(figs. 5 and 6). 

7
Of the 12,586 m of stream channel surveyed in 2006, 21% of the habitat units contained 

at least one bull trout. In 2006, 20% of the bull trout were found in pools and 16% of the habitat 

length we surveyed was pool habitat (table 7). In 2007, 50% of the habitat units surveyed 

contained at least one bull trout. Fifteen percent of these fish were found in pools and 12% of the 

habitat length we surveyed was pool habitat (table 7). In 2007, the upper end of our sampling 

was located higher in the basin (fig. 2), which may account for the greater number of habitat 

units containing bull trout. 

Pine Creek.—Sampling in Pine Creek in both years began at the confluence of Pine 

Creek and West Fork Jarbidge River (fig. 2). In July 2006, about 5.5 km of stream habitat were 

sampled, with the exception of about 1.8 km of middle Pine Creek. In August 2007, sampling 

was continuous over 5.9 km of stream, but stopped about 200 m downstream of the end of fish 

distribution (as assessed by visual survey). In 2006, 27 bull trout were captured and 25 were PIT 

tagged (table 1). In 2007, 430 bull trout were captured, of which 380 were PIT tagged (table 2). 

Fish lengths ranged from 39 to 387 mm (table 6) and most were age-1, as determined from 

length frequencies (fig. 7). In both years, we captured only a few bull trout longer than 200 mm 

(table 6, fig. 7). 

In 2007, we recaptured two bull trout that were originally PIT tagged in July 2006. The 

lengths of these fish at tagging were 108 and 162 mm and their annual growth rates were 57 and 

35 mm (adjusted to 1 year), respectively, with 397 days between tagging and recapture (fig. 7). 

In 2006, one age-0 (39 mm) bull trout was captured and age-1 fish were between 100 and 130 

mm, as determined from length frequency analysis (fig. 7). Age-0 bull trout captured in August 

2007 ranged between 55 and 68 mm, and age-1 fish were from 99 to 155 mm in length (fig. 7). 

In both years, bull trout were found mostly above 2,100 m altitude and in greater 

numbers and at higher abundances as altitude increased (figs. 8 and 9). Redband trout were 

found throughout the reaches sampled, but with reduced abundances in the highest altitudes. The 

middle reach of Pine Creek, which we did not sample in 2006, had the highest abundances of 

bull trout in 2007, with bull trout >200 mm long common. In 2006, only one age-0 bull trout was 

collected, whereas in 2007, several age-0 fish were captured in the reaches above 2,187 m 

altitude; figs. 7, 8, and 9). The highest altitude reaches had age-0 bull trout and redband trout 

present and relatively high abundances of bull trout overall. 

Only 14% of the habitat units surveyed in 2006 contained bull trout, but 83% of habitat 

units contained at least one bull trout in 2007. This discrepancy probably was due to more 

extensive sampling in the middle and upper reaches of Pine Creek in 2007. In 2007, about 10% 

of the bull trout were found in pools, though only 9% of the stream length sampled was pool 

habitat (table 7). 

Jack Creek.—In both years, sampling in Jack Creek began near the confluence with the 

West Fork Jarbidge River (fig. 2). In 2006, sampling began 20 m upstream of the PTIS (rkm 0.1) 

and continued to about rkm 4.3. We stopped sampling near this area because of fish spawning 

activity. On September 11, 2006, two pair of post-spawn bull trout were collected and several 

redds were observed. In 2007, our sampling began at the mouth of Jack Creek, continued to rkm 

5.9, and included a mark-recapture population estimate presented below. This sampling extended 

about 100 m past the uppermost distribution of fish, which appears to end at a small waterfall 

with a 60 m bedrock slide downstream. On September 11, 2007, 0.8 km of stream was sampled 

above the presumed end of fish distribution, and no fish were observed. In early September 2006, 

66 of the 70 bull trout captured were PIT tagged (table 1). In early August 2007, 101 of the 146 

bull trout captured were PIT tagged (table 2, fig. 2). The minimum fork length was 61 mm in 

8
2006 and 42 mm in 2007, and the maximum fork length was 310 and 283 mm (table 6), 

respectively. Most of the bull trout were age-1, with small percentages larger than 200 mm (11% 

in 2006, 10% in 2007; table 6, fig. 10). 

We recaptured 10 bull trout in August 2007 that were originally PIT tagged in September 

2006. The length of these fish at tagging ranged from 125 to 235 mm. The mean annual growth 

rate of these fish was 34 mm (range = 21–44 mm; SD = 4.8; fig. 10). Using length-frequency 

analysis, we determined that age-0 fish were less than 69 mm in early September 2006, age-1 

bull trout were 115–142 mm, and age-2 bull trout were larger than 145 mm (fig. 10). In August 

2007, age-0 bull trout were 42–62 mm, age-1 fish were 980–140 mm, and age-2 fish were 145–

190 mm (fig. 10). 

Consistent with findings in other streams in the upper Jarbidge River watershed, bull 

trout generally were found in greater numbers and at higher abundances at altitudes above 2,100 

m and in greater numbers and at higher abundances as altitude increased (figs. 11 and 12). 

Redband trout were found in high abundances in lower Jack Creek below about 2,100 m altitude. 

Bull trout presence extended 500–600 m upstream of the last observed redband trout in both 

years in Jack Creek. In 2006, bull trout longer than 200 mm were found in the middle and upper 

portions of Jack Creek (fig. 11), but in 2007, fish of this size were found only in one area, at rkm 

4.0 (fig. 12). In 2006, age-0 bull trout were found only at altitudes greater than 2,000 m. In 2007, 

however, age-0 bull trout were found about 0.5 km from the confluence, at about rkm 2.2, and 

also at rkm 4.2 near the high abundance of age-1 or older bull trout. 

Of the 5.2 km of Jack Creek surveyed in 2006, 29% of the habitat units contained at least 

one bull trout. Although only 10% of the stream length surveyed was pool habitat (table 7), 44% 

of the bull trout captured were in pools. In 2007, we surveyed 5.4 km of stream and 45% of the 

habitat units contained at least one bull trout. We captured 39% of the bull trout in pools, while 

only 8% of the length of stream was pool habitat (table 7). 

Deer Creek.—On September 10, 2007, we sampled Deer Creek from about rkm 6.9 to 

9.4. Several small redband trout were observed, but not counted. No bull trout were observed. 

The riparian vegetation in the reach sampled was very sparse. The stream had a mean depth of 

5 cm and very limited pool habitat. 

Buck Creek.—We sampled two short reaches of Buck Creek (from about rkm 3.6–3.8 and 

rkm 12.7–13.1) on September 14, 2007. The habitat in Buck Creek was similar to that in Deer 

Creek. It was about 7 cm deep, lacked defined pools, and had sparse riparian vegetation. In 

general, the stream had very low velocity, heavy siltation, and high turbidity. Redband trout were 

abundant; however, no bull trout were observed. 

East Fork Jarbidge River Watershed 

East Fork Jarbidge River.—In 2006, we sampled near the East Fork Jarbidge River 

antenna site (rkm 4.1–4.9) on October 3 and in the wilderness area upstream of the East Fork 

Jarbidge River/Slide Creek confluence (rkm 15.6) from August 17–19 (fig. 3). No bull trout were 

captured near the antenna site, but 13 were captured between rkm 16.6 and 24.7 (table 1). 

Sampling stopped at rkm 24.7 due to time constraints. We sampled the East Fork Jarbidge River 

(rkm 32.5–35.0) from July 12–14, 2007, and captured 323 bull trout, of which 312 were PIT 

tagged (table 3, fig. 3). We also sampled 250 m of an unnamed tributary at about rkm 33.5. 

Redband trout were absent, but 13 bull trout, ranging from 130 to 238 mm, were captured in this 

tributary (table 3, fig. 16). We encountered a 2.5-m-high falls with no plunge pool 250 m 

upstream of the mouth of the unnamed tributary. We sampled an additional 50-m reach upstream 

9
of this barrier and found no fish. On the mainstem East Fork Jarbidge River below the 

confluence of Slide Creek, we recaptured one bull trout on July 17, 2007, that was originally 

tagged in Fall Creek in August 2006 (table 3, fig. 3). We stopped sampling in 2007 at 

approximately rkm 35.0 due to time constraints. Visual surveys indicated that fish were likely 

present for at least another 0.5 km upstream of our end point based on habitat conditions and 

water quantity. However, this survey was brief and no fish were directly observed. 

The maximum size of fish tended to be larger in the upper East Fork Jarbidge River than 

anywhere else we sampled. In 2006, bull trout ranged in length from 135 to 260 mm (table 6) 

and in 2007 from 78 to 400 mm (table 6). Most of the fish we captured were age-3 or older, with 

a relatively high proportion of fish longer than 200 mm (38% in 2006; 19% in 2007) (table 6, fig. 

13). From length-frequency analysis, we determined that age-1 bull trout were between 78 to 100 

mm, age-2 bull trout were between 107 and 143 mm, and age-3 bull trout were 143 mm and 

longer in mid-July 2007 (fig. 13). The sample size was too small in 2006 to determine age 

classes. No age-0 bull trout were observed in the East Fork Jarbidge River during 2006 or 2007. 

In 2006, bull trout were uncommon but increased in abundance at altitudes above 2,100 

m near the upstream end of our survey (fig. 14). Redband trout were abundant throughout the 

area sampled in 2006. In 2007, bull trout were present at the downstream end of our sampling 

(fig. 15), were numerically dominant at about 2,290 m altitude, and were the only salmonid 

present above 2,320 m altitude. Bull trout abundance decreased upstream of the East Fork 

Jarbidge River confluence with an unnamed tributary and spring at rkm 33.5. In this area, stream 

depths were very shallow and the stream contained no surface flow for about 100 m. Surface 

flow and high numbers of bull trout were present upstream of the no-flow section and the 

channel substrate primarily was bedrock. On July 14, 2007, the last day of sampling the upper 

East Fork Jarbidge River, bull trout were the only salmonid present and were relatively abundant. 

We speculate that high abundance of bull trout continued at least another 0.5 km upstream as no 

barriers were present. 

In 2007, we recaptured a large bull trout (400 mm) at our lowermost sampling site in the 

East Fork Jarbidge River (fig. 3). This same fish was originally tagged in Fall Creek (see 

appendix, fig. A49) and had grown 40 mm and nearly doubled its weight in 331 days (440.6 to 

767.2 g, table 6). We recaptured no other PIT tagged fish in 2006 from the East Fork Jarbidge 

River. 

We surveyed 8 km of the East Fork Jarbidge River in 2006 and only 5% of the habitat 

units contained bull trout. We found 25% of the bull trout in pools, while 19% of the length 

sampled was pool habitat (table 7). In 2007, the survey in the East Fork Jarbidge River covered a 

higher altitude reach except for a short 0.4-km reach at the East Fork Jarbidge River/ Slide Creek 

confluence (fig. 3) and 52% of the habitat units sampled had bull trout (table 7). Nineteen 

percent of the bull trout we captured were in pools, while 13% of the stream length sampled was 

pool habitat. 

Cougar Creek.—We sampled Cougar Creek on July 11–12, 2007, starting at the 

confluence with the East Fork Jarbidge River and continuing upstream 0.7 km; no bull trout were 

observed in this reach (table 3 and fig. 3). Several temporary, low-flow fish barriers (mostly 

substrate and wood) were present. From about rkm 1.2–1.5, we captured one bull trout that was 

138 mm long. From rkm 1.8 to the limit of fish presence at rkm 3.1, we caught six bull trout, 

ranging in length from 180 to 340 mm (table 6, figs. 16 and 17). Here, the substrate was bedrock 

and the stream had a steep gradient above 2,100 m altitude. Although there were several 

cascading waterfalls and slides in this section, redband trout were relatively abundant. The end of 

10
fish distribution was a 2.5-m-high falls; we electrofished upstream of these falls an additional 

100 m, but no fish were observed. Cougar Creek was not sampled in 2006. Only 4% of the 

habitat units contained bull trout in Cougar Creek, and five of the seven bull trout we caught 

were in pools (table 7). 

Fall Creek.—We sampled Fall Creek on August 20, 2006, starting at the confluence with 

the East Fork Jarbidge River and continuing upstream for about 2.0 km (fig. 3). On July 15, 

2007, we sampled from rkm 1.4 to rkm 3.4, but did not find any fish upstream of rkm 3.2 (fig. 3). 

In 2006, we captured and PIT tagged nine bull trout (table 1). In 2007, 30 bull trout were 

captured and PIT tagged (table 3). The combined range of lengths of fish from both years was 

79–360 mm (table 6). Most of the bull trout in 2007 were age-1, with only a few age-2 fish 

present (fig. 18). The sample size of fish in 2006 was too small for age determinations. One bull 

trout longer than 200 mm that was PIT tagged in 2006 was subsequently recaptured in 2007 in 

the mainstem East Fork Jarbidge River (rkm 23.5) near the confluence with Slide Creek, about 

2.5 km from the tagging site. 

In 2006, bull trout were uncommon from the confluence with the East Fork Jarbidge 

River to about 1.0 km upstream (fig. 19). In 2007, bull trout were found with increasing 

frequency and abundance in the higher altitudes sampled (fig. 20). Four bull trout longer than 

200 mm were caught near the end of fish distribution (fig. 20). All size classes of redband trout 

were found throughout the length of stream sampled in 2006. In 2007, redband trout abundance 

decreased in the upper reaches of Fall Creek, and bull trout were the only salmonid present in the 

final 130 m of stream below a barrier waterfall. 

Of the 2.0 km of Fall Creek surveyed in 2006, only 8% of the habitat units contained bull 

trout. Twenty-two percent of the catch was from pools, and 14% of the stream length was pool 

habitat. Of the 1.8 km of stream sampled in 2007, 28% of the habitat units contained at least one 

bull trout, with 20% of the fish found in pools. Only 9% of the stream length sampled was pool 

habitat (table 7). 

Slide Creek.—On August 21, 2006, we sampled Slide Creek from its confluence with the 

East Fork Jarbidge River upstream to rkm 5.5, where we observed spawning bull trout. We did 

not sample two small sections in 2006, one from rkm 2.9 to rkm 3.2 and another from rkm 4.6 to 

rkm 5.4 (table 1, fig. 3). On July 16, 2007, we sampled the creek from rkm 4.6 to rkm 7.7 (table 

3 and fig. 3). In 2006, four bull trout were captured and PIT tagged (table 1) and in 2007, only 

three fish were captured and PIT tagged (table 3). The length of bull trout ranged from 189 to 

300 mm in 2006 and from 95 to 220 mm in 2007 (table 6 and fig. 21). On August 22, 2006, we 

observed two gravid bull trout (300 and 190 mm) and another spawning pair and therefore 

stopped sampling. In 2006, all four of the bull trout were captured at an altitude above 2,100 m 

(fig. 22). In 2007, two of the bull trout we caught were likely age-1 fish, on the basis of estimates 

of size at age from other fish in the East Fork Jarbidge River (fig. 21). The lengths of the few 

bull trout caught in 2007 varied widely, and the largest fish (220 mm) was caught very high in 

the watershed (fig. 23). No bull trout were caught in pools in either year (table 7, figs. 22 and 

23). All size classes of redband trout were found throughout Slide Creek in 2006 and 2007. 

Sampling efficiency generally was less in Slide Creek relative to that in other streams due to 

narrow stream width and thick riparian vegetation. 

Dave Creek.—In August 2006, we collected samples between rkm 6.8 and rkm 11.7 on 

Dave Creek and PIT tagged 111 of the 129 bull trout collected (table 1, fig. 3). We stopped 

sampling on August 6 because we encountered one sexually mature male bull trout and two bull 

trout paired together over spawning gravel. From June 28 through July 2, 2007, sampling started 

11
at rkm 6.8 and ended 80 m upstream of the last fish observed (at about rkm 14.0). We also 

repeated sampling from rkm 10.5 to 13.9 on September 11, 2007, to recapture PIT tagged fish for 

estimating summer growth rates. From June 28 through July 2, 2007, 105 bull trout were 

captured and 100 of these were PIT tagged (table 3, fig. 3). In September, a total of 23 bull trout 

were captured and 11 were newly PIT tagged. Seven recaptured bull trout were originally PIT 

tagged during our June 2007 sampling and three bull trout were recaptures from 2006. During 

this time, we captured three sexually mature, male bull trout, ranging in length from 153 to 200 

mm. 

The lengths of bull trout captured from Dave Creek in 2006 ranged from 97 to 229 mm 

(table 6). Most of the fish were age-1, with a few being longer than 200 mm (12% of the total 

catch; table 6, fig. 24). In 2007, the lengths ranged from 59 to 232 mm, and only 5% of the fish 

were longer than 200 mm (table 6). 

We recaptured three bull trout in Dave Creek during 2007 that were originally PIT tagged 

in 2006. These fish ranged from 108 to 114 mm at tagging and their mean annual growth rate 

was 37 mm (range = 35–39 mm; SD = 2.2; fig. 24). Using length frequency analysis, we 

determined age-1 bull trout fork lengths to range from 97 to 134 mm and age-2 fish ranged from 

140 to 180 mm in early August 2006 (fig. 18). We also recaptured seven bull trout in September 

2007 that were tagged in June 2007. The mean growth of these fish over 68 days was 11 mm 

(range: 1–22 mm). In late June 2007, the fork length of age-1 bull trout ranged from 83 to 127 

mm and age-2 fish were estimated to be between 140 and 175 mm (fig. 24). In September 2007, 

we did not collect enough fish to make a length frequency analysis; however, we collected four 

bull trout fry that ranged in length from 59 to 66 mm. 

In both years, bull trout were found in greater numbers and in higher abundances as 

altitude increased (figs. 25 and 26). Redband trout were present throughout Dave Creek, but 

abundance decreased at higher altitudes. In 2006, bull trout larger than 200 mm commonly were 

mixed with smaller fish (fig. 25). In 2007, however, bull trout larger than 200 mm primarily were 

found at high altitudes (fig. 26). 

We surveyed 4.9 km of Dave Creek in 2006 and 46% of the habitat units contained bull 

trout. About 15% of the bull trout were found in pools and 7% of the length of stream sampled 

was pool habitat (table 7). In 2007, 62% of the habitat units had bull trout, 10% of the bull trout 

were found in pools, and only 2% of the survey length was pool habitat. 

Overall Distribution and Abundance of Bull Trout in Jack Creek 

In 2007, we estimated the population for age-1 or older bull trout in the fish-bearing 

portion (lower 5.3 km) of Jack Creek. Because of the low number of bull trout captured in the 

lower section of Jack Creek (downstream of Jenny Creek, n=6, with 2 recaptured bull trout), we 

did not calculate a population estimate in that section. In the 3.6 km upstream of Jenny Creek, we 

captured and marked 66 bull trout during our first effort, and during our second effort, 23 of the 

52 fish collected had marks from the initial sampling. This yielded a population estimate of 153 

bull trout (SD = 17.5; CV = 11.9; 95% CI = 114–220). During our recapture efforts in upper Jack 

Creek, we collected 35% of the fish tagged the day before. In our recapture efforts in lower Jack 

Creek, we collected 33% of the fish tagged the day before. This indicates that our one-pass 

electrofishing effort had a catchability of 35% over the 5.3 km of stream. 

12
For the streams in which bull trout were present, regression analysis indicated a 

significant correlation (P < 0.001, R2 = 0.06) between bull trout abundance and altitude. We also 

found a highly significant correlation (P < 0.001, R2 = 0.01) between the number of bull trout 

(per m) and pool depth. The low R2 values indicate that although altitude and pool depth have a 

significant relationship to bull trout abundance, they explain only a small amount of the 

variation. We should make clear that bull trout abundance was relative because we conducted 

only a single upstream sampling pass with no block nets, and capture efficiency was variable due 

to several factors (temperature, light, crew experience, substrate, for example). No other relations 

were evident between the relative abundance of bull trout and other habitat features that were 

quantified, such as pool cover (large and small wood, substrate, and undercut bank), riparian 

shade, and wetted width. 

Movements of Bull Trout 

In 2006, the PTISs at West Fork Jarbidge River (rkm 15.0), East Fork Jarbidge River 

(rkm 4.1), and Jack Creek (rkm 0.1) were operated from September 15 to December 18, 2006, 

when they were removed for the winter. During that time, five bull trout were detected moving 

downstream at the West Fork Jarbidge River site, with one of these fish first detected by the 

PTIS in Jack Creek (table 8; figs. A3, A14, A26, and A28). Three of the five fish were tagged in 

the West Fork Jarbidge River, one was tagged in Pine Creek, and one in Jack Creek. All fish 

were detected moving downstream after October 7, 2006 (figs. A3, A14, A26, A28, and A30). 

We detected no fish on the PTIS at the East Fork Jarbidge River site. 

In 2007, we re-installed and operated the PTISs in the West Fork Jarbidge River, East 

Fork Jarbidge River, and Jack Creek and also installed a system in Dave Creek, at the 

confluences of the West Fork Jarbidge River and Pine Creek and the East Fork Jarbidge River 

and West Fork Jarbidge River at the Forks (table 8). All systems were operated from April to 

mid-December. Although the single antenna systems in Jack and Dave Creeks were 

intermittently affected by antenna noise that may have reduced their detection efficiency (fig. 

27), test tags passed weekly through these systems indicated no such loss in efficiency. The 

larger MUX systems were, in general, fully operational (fig. 27), but some conditions, such as 

low battery power, electronics malfunctions, and extreme temperatures may have reduced their 

detection efficiency. Maintaining an adequate battery voltage, by charging with solar power or 

replacing batteries, was difficult as winter approached because of the remote location combined 

with decreased sunlight and temperatures. 

Three upstream and four downstream directional movements of bull trout were detected 

at the PTIS on the East Fork Jarbidge River at Murphy Hot Springs or the East Fork and West 

Fork PTIS antennas at the Forks (fig. 28). In both years, the majority (83%) of fish interrogated 

at the three PTISs in the West Fork Jarbidge River were moving downstream (fig. 29). However, 

two fish moved upstream in Jack Creek and one fish moved upstream at the mainstem West Fork 

Jarbidge River PTIS at rkm 15. The upstream movements of fish in Jack Creek occurred in late 

spring as the main West Fork Jarbidge River approached base flows and water temperatures 

increased. 

Appendix figures A1 through A50 show all data for fish interrogated in 2006 and 2007, 

and fish that showed evidence of movement by recapture. There were 44 new interrogations of 

PIT tagged bull trout in 2007 (table 8), and one fish from Jack Creek that was interrogated in 

both 2006 and 2007 (fig. A3). Most fish that were detected were tagged in the West Fork 

Jarbidge River or its tributaries, but two fish were tagged in Dave Creek. In Dave Creek, one fish 

13
(195 mm) was tagged in August 2006 and detected on April 29, 2007, at the PTIS in the East 

Fork Jarbidge River at Murphy Hot Springs. The other bull trout (164 mm) was tagged in Dave 

Creek on June 28, 2007, and detected at both the East Fork and West Fork PTIS antennas at the 

Forks on July 28, 2007, but this fish was not detected at the PTIS on Dave Creek (installed on 

May 23, 2007) or the PTIS on the East Fork Jarbidge River at Murphy Hot Springs (figs. A1 and 

A2). Both of these fish were tagged in a similar location. 

Bull trout in Jack Creek showed several movement patterns, with fish tagged at relatively 

high altitudes in the drainage basin leaving the creek and inhabiting the West Fork Jarbidge 

River, the East Fork Jarbidge River, and presumably the mainstem below the Forks. In 2007, 

only two bull trout were detected by the PTIS in the West Fork Jarbidge River (rkm 15), and 

they were tagged in Jack Creek (table 8). Fish tagged in the upper reaches of Jack Creek tended 

to emigrate in mid-July (figs. A4 through A8 and A10). For example, one bull trout (175 mm) 

tagged near the upper end of fish distribution in 2006 was detected moving out of Jack Creek on 

July 13, 2007. This fish was detected moving past the PTIS at the Forks on November 20, 2007 

(fig. A6). Another bull trout (138 mm) tagged in the upper reaches was detected on the Jack 

Creek PTIS on July 21, 2007. This fish was then detected 2 days later moving downstream 

through the PTIS at the Forks (fig. A7). Two fish (138 and 171 mm), tagged in the lower 

sections of Jack Creek in early August 2007, were detected emigrating from the creek in 

November 2007 (figs. A11 and A12). Finally, one bull trout tagged in the upper reaches of Jack 

Creek in September 2006 was detected on the PTIS at the East Fork Jarbidge River at Murphy 

Hot Springs moving downstream on August 26, 2007, and was detected later on October 19, 

2008, in the West Fork Jarbidge River at the Forks moving upstream (fig. A9) 

The PTIS at the confluence of the West Fork Jarbidge River and Pine Creek had many 

more fish detections than any of the other PTIS locations (table 8). Fish tagged in the upper West 

Fork Jarbidge River had the highest number of interrogations, with 20 fish detected at the West 

Fork Jarbidge River/Pine Creek site (table 8). Ninety percent of these fish were moving down the 

West Fork Jarbidge River from September through November (fig. 29). Ten of the fish tagged in 

the West Fork Jarbidge River were detected or recaptured in Pine Creek, indicating a relatively 

high degree of connectivity between these watersheds (figs. A21, A22, A24, A25, A27, A35, 

A39, A42, A44, and A48). We detected eight fish at the West Fork Jarbidge River/Pine Creek 

site that were tagged in Pine Creek, seven of which were emigrating downstream between 

October 7 and November 4, 2007. The eighth fish was detected moving downstream at the same 

time of year on November 3, 2006, at the PTIS on the West Fork Jarbidge River (rkm 15), 

however, the PTIS at West Fork Jarbidge River/Pine Creek (rkm 26.2) was not established until 

2007 (fig. A14). Bull trout were detected at the West Fork Jarbidge River/Pine Creek site 

continuously during the summer and detections decreased as winter approached (fig. 29). Bull 

trout were detected at the interrogation systems nearly all hours of the day, but with a higher 

frequency during the night (fig. 30). 

Distribution, Growth, and Movement of Bull Trout 

Findings from the 2006 and 2007 electrofishing surveys suggest that bull trout 

populations with recruitment to age-1 fish occurred in Pine, Jack, Dave, and Fall Creeks as well 

as the West Fork and East Fork of the Jarbidge River at altitudes above 2,100 m. Few bull trout 

were observed in Cougar and Slide Creeks, indicating that stable reproductive populations were 

not present in those creeks at the time of the survey. The results of the genetic analysis reporting 

on the relatedness between sub-populations of bull trout from the streams described above were 

14
highly supportive of our distribution and movement findings and can be found in DeHaan and 

others (2007). No bull trout were found in Deer and Buck Creeks, however, migratory bull trout 

may inhabit those streams intermittently. 

General Catch Information and Population Characteristics 

During 2 years of sampling in the upper Jarbidge River watershed, we captured 1,702 

bull trout (80% of which were captured in 2007) and counted more than 4,000 redband trout in 

pools only. Bull trout were found primarily at altitudes above 2,100 m (87% of all those 

encountered), which was consistent with the findings in other studies that the distribution of 

juvenile bull trout within streams was strongly associated with altitude (Dunham and Rieman, 

1999; Paul and Post, 2001; Dunham and others, 2003a; Ripley and others, 2005). 

Redband trout were found in all areas where bull trout were sampled, except in the upper 

reaches of fish distribution in East Fork Jarbidge River and Jack Creek, where bull trout were the 

only salmonid present. In streams with notable bull trout populations (such as the headwaters of 

the East Fork and West Fork Jarbidge River, and Dave, Fall, Pine, and Jack Creeks), the relative 

abundance of redband trout decreased as the upper limit of fish distribution was approached. The 

relative abundance of bull trout tended to increase and that of redband trout decreased with 

increasing altitude. One explanation for the change in numerical dominance of bull trout over 

redband trout with altitude is that altitude can serve as a surrogate for stream temperature 

(Dunham and others, 2003b; Rieman and others, 2007). In upper reaches of those studies, most 

streams had an abundance of cobble and boulder substrates with interstitial spaces for cover, and 

relatively cool temperatures, conditions typical of good bull trout habitat in other streams (Fraley 

and Shepard 1989; Rieman and others, 2007). The ability of bull trout to dominate the upper, 

higher altitude reaches of streams could be due to their superiority in interspecific interactions, 

and may be an example of biotic resistance exerted by bull trout (Elton, 1958). Biotic resistance 

through predation, which can contribute to invasion or colonization resistance (Harvey and 

others, 2004; Ward and others 2008), seems probable given the highly piscivorous nature of bull 

trout (Fraley and Shepard, 1989; Donald and Alger, 1993). 

The distribution of bull trout and redband trout in streams of the Jarbidge River basin 

could change if temperatures increase due to climate change or other factors. For example, 

increasing stream temperatures could favor redband trout, leading to an expansion of their 

distribution, restricted distributions of bull trout, and a decrease in the competitive ability of bull 

trout (Rieman and others, 2007). When bull trout distributions become restricted, they may be 

unable to reclaim dominance to their full historical range because of biotic resistance from 

redband trout occupying those reaches. In short, on the basis of potentially higher stream 

temperatures alone, more habitat would be suitable for redband trout and less for bull trout. The 

area of transition in dominance of bull trout over redband trout, however, may be an important 

aspect to monitor relative to the sustainability of bull trout in the Jarbidge River watershed. 

Using a mark-recapture procedure, we estimated that there were about 153 bull trout in 

Jack Creek upstream of Jenny Creek (95% CI = 114 – 220). Our estimate was similar to that of a 

single pass survey by NDOW, which reported about 102 bull trout for the entire Jack Creek in 

2002 (Johnson, 2002). From the mark-recapture data, our one-pass capture efficiency was 

estimated to be 35%, and methods similar to ours could be used to evaluate changes in bull trout 

abundance over time in Jack Creek. In fact, estimating the abundance of bull trout in Jack Creek 

could become a routine method for status and trends monitoring in the Jarbidge River basin. We 

do not, however, recommend extrapolating our sampling efficiency estimate from Jack Creek to 

15
other streams to estimate fish abundance by simply dividing the number of fish captured in a 

stream by 0.35 to obtain an estimate of abundance. Electrofishing sampling efficiency can vary 

widely depending upon many factors, including crew experience, equipment type, fish size, fish 

abundance, stream width, stream flow, temperature, water clarity, cloud cover, and sun position 

(Zalewski and Cowx, 1990). It seems prudent to keep Jack Creek as a status and trends 

monitoring site for future bull trout population abundance estimates and perhaps to establish 

reference sites in other streams to monitor relative abundance. 

Length-frequency distributions of bull trout in streams of the upper Jarbidge River 

watershed were generally similar and were dominated by age-1 and age-2 fish. This is indicative 

of good reproduction success and suggests that older bull trout might show a fluvial life history 

and therefore be absent from our sample. An exception to this conclusion was found in the upper 

East Fork Jarbidge River (sampled in 2007), which was dominated by age-3 or older fish, 

although it should be noted that the uppermost fish distribution was not reached and there may 

have been younger fish in this area. The dominance of older fish suggests that the numbers of 

age-1 and age-2 fish were suppressed by predation (cannibalism) or that younger fish emigrate to 

rear in the lower mainstem East Fork Jarbidge River or tributaries. Beauchamp and Van Tassell 

(2001) found that bull trout of all sizes were capable of eating fusiform prey fishes of up to 50% 

of their own total length. They also used model simulations and field data to show that 

cannibalism by bull trout could remove substantial proportions of age-0 and age-1 fish, but not 

age-2 or older fish in Lake Billy Chinook, Oregon. Diet analysis of piscivorous-sized bull trout 

would be required to confirm this notion in the upper East Fork Jarbidge River. 

The length of age-1 bull trout varied temporally, ranging from 68 mm in the West Fork 

Jarbidge River on June 21, 2006, to 145 mm in Pine Creek on August 22, 2007, similar to fish in 

other basins, such as the Flathead River, Montana (Fraley and Shepard, 1989), Metolius River, 

Oregon (Ratliff, 1992), Kananaskis Lake in Alberta, Canada (Stelfox, 1997), and the Cedar 

River, Washington (M. Mesa, U.S. Geological Survey, unpub. data, 2008). 

Age-0 bull trout probably did not begin to emerge until late June or later in most 

tributaries of the upper Jarbidge River watershed. We collected 5 age-0 bull trout in 2006 and 83 

in 2007. Our sampling did not target age-0 fish; however, the lack of very small (< 30 mm) fish 

in our catches probably reflects the timing of our sampling and the low susceptibility of this 

portion of the age group to our sampling gear. Small fish are less vulnerable to capture by 

electrofishing than are larger fish, they are less visible to netters, and their body size facilitates 

hiding in interstitial spaces of the streambed material (Reynolds, 1983). Low numbers of age-0 

bull trout observed in most streams was probably not a result of poor hatching success or low 

survival. However, given the high numbers of bull trout collected in the upper East Fork Jarbidge 

River and Fall Creek, we speculate that if age-0 fish were present at that time of year, we would 

have at least observed some of them. 

By examining length-frequency distributions and assigning ages to the distinct modes, we 

estimated the age and growth rates for younger bull trout. This technique worked well for age-0 

and age-1 fish, but not for older fish. The largest age-0 fish we collected was 69 mm and most 

age-1 fish were larger (range: 78–145 mm). It was more difficult to estimate the size ranges of 

age-2 or older bull trout because individual growth rates were highly variable and the age breaks 

between age-2 and age-3 fish were unclear. Recapturing PIT tagged bull trout allowed us to 

validate the age assignments of the length frequency histograms and to estimate the growth rates 

of older age classes. 

16
Although the sample sizes of recaptured PIT tagged fish in any stream during our study 

were small, they were sufficient to provide some insight into annual growth rates. Of the 25 fish 

tagged in 2006 that were recaptured in 2007, 3 were from Dave Creek, 1 from East Fork Jarbidge 

River, 5 from Pine Creek, 6 from West Fork Jarbidge River, and 10 from Jack Creek. The mean 

annual growth rate was 36 mm for all recaptured bull trout (n = 23) and ranged from 32 mm in 

the West Fork Jarbidge River to 38 mm in Pine Creek. These mean annual growth rates compare 

favorably with those of bull trout in other areas, such as 28 mm in Trestle Creek, Idaho (Downs 

and others, 2006). There are several possible reasons for the low number of fish tagged in 2006 

being recaptured later. First, because the number of tags deployed in 2006 was much fewer than 

in 2007, there were simply fewer tagged fish available in 2007 that were tagged in 2006. Second, 

our sampling in 2006 generally took place lower in the watersheds compared to our work in 

2007, when we focused activity towards the upper end of fish distribution. Third, the probability 

of over-winter mortality of fish in the basin seems high (because of low winter flow, anchor ice 

formation, and relatively sparse abundance of deep pools in areas where bull trout were more 

common), which would reduce the recapture potential. It is possible that some shedding of PIT 

tags occurred. Although we tagged all bull trout greater than 120-mm fork length in the dorsal 

sinus to minimize tag loss, we do not know the rate of tag loss for bull trout tagged in this area. 

Dieterman and Hoxmeier (2009) found that brook trout and brown trout (Salmo trutta) tagged in 

the dorsal musculature had high tag retention rates—100% and 95%, respectively, over 2 months 

in small streams. Finally, there also is a possibility that tagged fish emigrated out of the area 

sampled in 2007. If this movement occurred when the PTISs were not operating, we would not 

be aware of it. All these factors could contribute to low recapture rates of PIT tagged bull trout 

on an annual basis. 

There was no clear longitudinal gradient in fish size or propensity to emigrate as we 

progressed from downstream to upstream areas in the Jarbidge River watershed. Some studies 

have shown that fish become smaller with progression upstream, because fish size was related to 

stream depth observed at the habitat unit scale (see, for example, Patrick. 1975; Schlosser, 1982; 

Anderson, 1985). Hughes (1998) suggested, however, that this relationship does not always 

apply to drift-feeding stream salmonids. The lack of a longitudinal gradient in bull trout size in 

our streams was probably due to the relatively small size of our streams and that bull trout can 

show considerable intra-stream movements (see discussion below), which would help distribute 

fish of different sizes throughout the stream. 

Movement of Bull Trout 

In general, the PTISs were effective at detecting upstream and downstream movements of 

bull trout and documenting connectivity between headwater and mainstem areas. Bull trout were 

detected moving from upper ends of fish distribution in the West Fork Jarbidge River (n=13), 

Pine Creek (n=5), and Jack Creek (n=7) to the lower West Fork Jarbidge River below the 

confluence with Jack Creek. Fish from Jack (n=4) and Dave (n=1) Creeks were detected at the 

confluence of the East Fork and West Fork Jarbidge River. When the data on fish movements 

detected by the PTISs through December 2007 are combined, they indicate some degree of 

connectivity between headwater populations and the mainstem East Fork Jarbidge River and 

West Fork Jarbidge River. 

There was a pulse of downstream movement of fish in October and November 2007 from 

Pine Creek, West Fork Jarbidge River (rkm 26), and Jack Creek, most likely associated with 

declining temperatures and a slight increase in flow. While downstream movements of fish at the 

17
West Fork Jarbidge River and Pine Creek confluence PTIS (at rkm 26) peaked in October, 

downstream movement was detected at that site in all months that the PTIS was operating. 

Downstream movement by bull trout in the fall has been documented in other systems, including 

the Flathead River system in Montana (Muhlfeld and Marotz, 2005), the Boise River in Idaho 

(Monnot and others, 2008), Trestle Creek in Idaho (Downs and others, 2006), Grand Ronde 

River system in Oregon (Bellerud and others, 1997), and the Arrow Lakes region in British 

Columbia (McPhail and Murray, 1979). Bull trout in the Grand Ronde system were fluvial fish 

and those in the Flathead River, Boise River, Trestle Creek, and the Arrow Lakes region had 

adfluvial life histories. All these studies suggest that the autumn emigration of juvenile bull trout 

correlates with decreasing water temperatures. There also were some downstream movements of 

fish out of Jack Creek in mid-July with some of these fish detected moving down the West Fork 

Jarbidge River past the Forks within a few days, and some even entering the East Fork Jarbidge 

River. It appears that some bull trout, particularly from Jack Creek, migrate downstream of the 

Forks and inhabit the mainstem Jarbidge River, but the extent or duration of mainstem habitat 

use is unclear. In the Flathead River system, juvenile bull trout emigrated primarily from June 

through August (Fraley and Shepard, 1989). 

Detections of upstream movement of bull trout were relatively rare (17% of all 

movement detected from PTISs) compared with detections of downstream movement. However, 

most of the fish we tagged were juvenile fish that may not become migratory for several years. 

Most of the upstream movements (62%) were detected at the Pine Creek and West Fork Jarbidge 

River confluence (rkm 26). These fish appeared to be moving back and forth, potentially rearing 

in the vicinity of the PTIS. Other upstream movements of fish were detected at PTISs at West 

Fork Jarbidge River (at rkm 15) and Jack Creek. These upstream movements occurred in June 

2007 as the West Fork Jarbidge River flows were decreasing and water temperatures were 

increasing. Other investigators have found that peak upstream movements of fluvial bull trout in 

Montana’s Blackfoot River occurred during the spring as water temperatures were increasing 

(Swanberg, 1997; Homel and Budy, 2008). These fish may have been on spawning migrations. 

As evidence of this, the largest bull trout tagged in Jack Creek (310 mm) out-migrated in 

October 2006 and returned the following June to Jack Creek (fig. A3). Seasonal movement of 

juvenile bull trout (upstream migrations in the spring and downstream in the fall) have been 

reported by others in Trestle Creek, Idaho (Downs and others, 2006) and South Fork Walla 

Walla River, Oregon (Homel and Budy, 2008). Continued operation of the PTISs in the Jarbidge 

River basin would allow for additional detections to confirm these life history trends for 

migrating fish. 

Seasonal fish barriers, primarily downed wood and substrate, were present during low 

flows in the West Fork Jarbidge River upstream of Pine Creek and in lower Cougar Creek. 

Similar temporary barriers may form in any of the streams we sampled, may not be present every 

year, and likely form during low-flow conditions. Such conditions may prevent bull trout from 

reaching areas used for spawning or rearing, thus isolating some fish in tributaries intermittently. 

Because bull trout may access their spawning areas during low-flow conditions in the fall, these 

temporary barriers may decrease inter-annual distribution, but increase straying and gene flow 

among certain populations. This may be true of the bull trout in the upper West Fork Jarbidge 

River and Pine Creek populations as well as the Cougar Creek and East Fork Jarbidge River 

populations, although there was little evidence of juvenile recruitment in Cougar Creek during 

our survey. 

18
Results from this and other studies (Fraley and Shepard, 1989; Rieman and MacIntyre 

1993; Bellerud and others, 1997; Haas and McPhail, 2001) show substantial variation in 

migration behavior of bull trout, which is associated with many factors, including water 

temperatures, stream discharge, fish size, food availability, and spawning. Bull trout also can be 

highly migratory during non-spawning periods (Muhlfeld and others, 2003; Downs and others, 

2006; Brenkman and others, 2007). The movements of bull trout in the Jarbidge River system 

indicate a high degree of connectivity between fish in different streams. Maintenance and 

potential enhancement of this connectivity will likely promote expression of important life 

history diversity (Muhlfeld and Marotz, 2005), which would contribute to the persistence of the 

population under varying habitat and climate conditions (Dunham and others, 2003a; Rieman 

and others, 2007). 

Most of the bull trout (89%) emigrating downstream in the Jarbidge River basin were 

age-2 or older, with a few age-1 fish migrating from the West Fork Jarbidge River, Pine Creek, 

and Jack Creek. The fish detected at the PTISs tended to be the larger individuals within their 

age class. Although we cannot know the actual length of a tagged fish at the time of detection, 

we assumed that the size of fish at tagging was representative of its size relative to its cohort 

when detected. Our results were consistent with others describing an emigration of smaller bull 

trout (for example, Fraley and Shepard, 1989; Bellerud and others, 1997; Downs and others, 

2006). Fraley and Shepard (1989) reported that 81% of the emigrating juvenile bull trout from 

the Flathead River system were ages 2 and 3. Mogen and Kaeding (2005) also observed that 

juvenile bull trout commenced migrations at age 2 or 3. Because larger fish may have a greater 

burst swim speed ability (Mesa and others, 2004), and would be less vulnerable to predation due 

to their larger size, migrating at a larger size could increase survival probability. A similar 

situation could exist in the Jarbidge River where emigrating at a relatively large size might have 

survival advantages and play a role in the persistence of a fluvial life history. 

We were unable to estimate the efficiency and precision of the PTISs in the Jarbidge 

River basin because of their configuration or an insufficient number of detections. Too few 

detections were available to estimate detection efficiencies for the systems with multiple antenna 

arrays. Estimating antenna efficiencies in Dave or Jack Creeks was not possible because there 

was only one antenna at each site. However, the efficiency of any PTIS would vary over time 

and is influenced by stream discharge, the direction of fish movements, intermittency in PTIS 

operation due to low battery power, and malfunctioning electronics. 

We maintained a reasonably good record of operation at the sites and continued to 

improve antenna anchoring and electronic system stability. Because our systems were based on 

the designs used by Connolly and others (2008) and the sizes of our streams were similar to 

those in their study, we surmise that detection efficiencies of our systems were good when the 

complete detection systems were intact. Their work showed that detection efficiencies of 

multiple antennas arranged in a series of arrays exceeded 96% under a variety of dynamic stream 

conditions. The systems tested by Connolly and others (2008) had three arrays, so that if any one 

array failed, two other arrays would still be able to determine the direction of fish movement and 

allow an estimate of detection efficiency. The systems in the Jarbidge River consisted of one or 

two arrays, and therefore had less redundancy, a reduced ability to determine the direction of 

movement or calculate detection efficiencies, and likely lower detection efficiencies than the 

systems described in Connolly and others (2008). 

19
Conclusions, Summary, and Recommendations 

Prior to the study described here, little was known about the bull trout population in the 

upper Jarbidge River basin, and biologists estimated that fewer than 500 bull trout were present 

within the core area defined by the U.S. Fish and Wildlife Service (2004). Our results indicate 

that almost four times that many bull trout inhabit the core area and that these fish show 

substantial movements between tributaries, increased abundance with increasing altitude, and 

growth rates indicative of a high-quality habitat. Our estimate of population size of bull trout in 

Jack Creek should provide a baseline that will allow managers to monitor changes in abundance 

over time. Further, our work included some information on the abundance of redband trout that 

provides an understanding of the distribution of these fish relative to that of bull trout. 

Collectively, our results provide new insight into the ecology and biology of bull trout in the 

upper Jarbidge River watershed that should prove useful for developing recovery actions and 

managing these fish. 

Our research was successful in documenting some important population and movement 

characteristics of bull trout in the Jarbidge River basin. We documented the relative abundance 

of bull trout throughout the watershed, their annual and seasonal growth rates, the timing and 

magnitude of downstream migrations, and the timing of the onset of spawning. Bull trout were 

found primarily in the upper parts of tributaries at altitudes greater than 2,100 m and numerically 

dominated redband trout in the upper East Fork Jarbidge River and Jack Creek. Redband trout, 

however, were more numerous throughout the rest of the watershed. Bull trout from the upper 

East Fork Jarbidge River, upper West Fork Jarbidge River, and Dave, Jack, and Pine Creeks had 

length-frequency distributions indicative of healthy populations with good potential for growth 

in body size and number. The annual growth rates of individual bull trout in the basin ranged 

from 21 to 61 mm and were indicative of good habitat conditions and within the range reported 

for bull trout elsewhere. Although bull trout showed some downstream movement during the 

spring and summer, most of their emigration occurred in autumn. Most of the fish that moved 

downstream were age-2 or older, which is typical of bull trout in other areas. We do not know 

the extent or timing of emigrations of age-0 fish, an important omission from this study. 

We do not know the contribution of different age classes and life history strategies to 

juvenile and adult production. Certainly, maintaining the expression of life history diversity, 

spread over multiple age classes, will help these fish survive temporal habitat disturbances. The 

contribution of various life history strategies expressed by juvenile bull trout could be evaluated, 

at least in part, by simply maintaining the current network of PIT tag interrogation systems. 

Much effort was expended to PIT tag juvenile bull trout, and those with successful life history 

strategies will mature and should be detectable by the interrogators used in this project for years 

to come, as well as by recapture when electrofishing or trapping. With a minimum of 

maintenance, PIT tag interrogators should be able to collect data documenting the timing of 

spawning migrations and periods when fluvial, adult fish use river and stream habitat. Because 

the PIT tag interrogation systems continued to operate in 2008 and 2009, additional information 

on fish movements was collected and more information will be available about the success of 

different juvenile life histories and from adult fish behavior and use of tributaries in the Jarbidge 

River basin. In addition, and of substantial ecological and management significance, the PTISs 

and the resultant data they provide will establish a baseline for monitoring changes in fish 

behavior in response to future environmental changes. 

20
To document changes in the Jarbidge River bull trout population over time, we suggest a 

sampling regime that combines a broad comparison of relative fish abundance and distribution in 

several tributaries with a more detailed population estimate in one or more streams. For now, we 

suggest that a mark-recapture population estimate be conducted in Jack Creek every 3-5 years. 

We also suggest monitoring fish population trends via single-pass electrofishing in upper West 

Fork Jarbidge River, Pine Creek, and Dave Creek at regular intervals, such as every 3 to 5 years. 

These streams should be targeted based on their relative bull trout abundance and the ease of 

accessibility for field crews. We expect that as repeated measures become available, trends in 

population characteristics should become evident. 

Acknowledgments 

We want to acknowledge all the members of the Bull Trout Recovery Team, especially 

Selena Werdon and Allen Taylor of the USFWS, for their involvement, interaction, and funding 

support. We thank Steven Buschback, Emily Hite, Jason Olds, Dawn Hunt, Carrie Munz, and 

Brien Rose of United States Geological Survey’s Columbia River Research Laboratory for 

working tireless hours in the field. We thank Kate Forster, Daniel Armichardy, Jessica 

Stegmeier, Matthew Kowalski, and Josh Uriarte from the Bureau of Land Management in Twin 

Falls for their placement of thermographs, collection of water temperature data, and assistance in 

fish sampling and maintaining and downloading the PIT tag interrogation systems. We also 

thank the personnel at the United States Forest Service, Wells District Ranger Station for use of 

the Mahoney facility for housing and equipment storage. Krinn and Chuck McCoy of the 

Tshawhawbitts Bed and Breakfast hosted the field crew and provided information on the area. 

We would like to recognize Gary Johnson and Caleb Cotton of Nevada Department of Wildlife 

for their help maintaining the PIT tag interrogation systems. We appreciate the many volunteers 

for the pack trips and the horse pack leaders in 2006 and 2007. We thank Kenney Baird for 

allowing us to store equipment on his property; and we thank the citizens of Jarbidge, Nevada, 

for their patience and many interesting conversations. 

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Hughes, N.F., 1998, A model of habitat selection by drift-feeding stream salmonids at different 

scales: Ecology, v. 79, p. 281-294. 

McPhail, J.D., and Murray, C.B., 1979, The early life history and ecology of Dolly Varden 

(Salvelinus malma) in the upper Arrow Lakes: Unpublished report to the British Columbia 

Hydro and Power Authority and the Fish and Wildlife Branch, Kootenay Region, Cranbrook, 

British Columbia. 

Mesa, M.G., Weiland, L.K., and Zydlewski, G.B., 2004, Critical swimming speeds of wild bull 

trout: Northwest Science, v. 78, p. 59-65. 

Mogen, J.T., and Kaeding, L.R., 2005, Identification and characterization of migratory and 

nonmigratory bull trout populations in the St. Mary River drainage, Montana: Transactions of 

the American Fisheries Society, v. 135, p. 841-852 

Monnot, L., Dunham, J.B., Hoem, T., and Koetsier P., 2008, Influences of body size and 

environment factors on autumn downstream migration of bull trout in the Boise River, Idaho: 

North American Journal of Fisheries Management, v. 28, p. 231-240. 

Muhlfeld, C.C., Glutting, S., Hunt, R., Daniels, D., and Marotz, B., 2003, Winter diel habitat use 

and movement by subadult bull trout in the upper Flathead River, Montana: North American 

Journal of Fisheries Management, v. 23, p. 163-171. 

Muhlfeld, C.C., and Marotz, B., 2005, Seasonal movement and habitat use by subadult bull trout 

in the upper Flathead River system: North American Journal of Fisheries Management, v. 25, 

p. 797-810. 

Patrick, R., 1975, Structure of stream communities, in Cody, M.L., and Diamond, J.M., eds.: 

Ecology and evolution of communities: The Belknap Press of Harvard University Press, 

Cambridge, Mass., p.445-459 

Paul, A.J., and Post, J.R., 2001, Spatial distribution of native and nonnative salmonids in streams 

of the eastern slopes of the Canadian Rocky Mountains: Transactions of the American 

Fisheries Society, v. 130, p. 417–430. 

Ratliff, D.E., 1992, Bull trout investigations in the Metolius River-Lake Billy Chinook System, 

in Howell, P.J., and Buchanan, D.V., eds., Proceedings of the Gearhart Mountain Bull Trout 

Workshop: American Fisheries Society, Oregon Chapter, Corvallis, Oreg., p. 37-44. 

Reynolds, J.B., 1983, Electrofishing, in Nielson, L.A., and Johnson, D.L., eds., Fisheries 

techniques: American Fisheries Society, Bethesda, Md., p. 147-163 

Rieman, B.E., and McIntyre, J.D., 1993, Demographic and habitat requirements for conservation 

of bull trout: U.S. Forest Service General Technical Report INT-308. 

Rieman, B.E., Isaak, D., Adams, S., Horan, D., Nagel, D., Luce, C., and Myers D., 2007, 

Anticipated climate warming effects on bull trout habitats and populations across the interior 

Columbia River basin: Transactions of the American Fisheries Society, v. 136, p. 1552-1567. 

Ripley, T., Scrimgeour, G., and Boyce, M.S., 2005, Bull trout occurrence and abundance 

influenced by cumulative industrial developments in a Canadian boreal forest watershed: 

Canadian Journal of Fisheries and Aquatic Sciences, v. 62, p. 2431-2442. 

Schlosser, I.J., 1982, Fish community structure and function along two habitat gradients in a 

headwater stream: Ecological Monographs, v. 52, p. 395-414. 

Seber, G.A.F., 1982, The estimation of animal abundance and related parameters, 2nd ed.: 

Macmillan Publishing Company, Inc. New York. 

23
Stelfox, J.D., 1997, Seasonal movements, growth, survival and population status of the adfluvial 

bull trout population in lower Kananaskis Lake, Alberta, in Mackay, W.C., Brewin, M.K., and 

Monita, M., eds., Friends of the Bull Trout conference Proceedings: Bull Trout Task Force 

(Alberta), c/o Trout Unlimited Canada, Calgary, p. 309-316 

Swanberg, T., 1997, Movements of and habitat use of fluvial bull trout in the Blackfoot River, 

Montana: Transactions of the American Fisheries Society, v. 126, p. 735-746. 

U.S. Fish and Wildlife Service, 2004, Draft Recovery Plan for the Jarbidge River Distinct 

Population Segment of Bull Trout (Salvelinus confluentus): U.S. Fish and Wildlife Service, 

Portland, Oreg. 

Ward, D.M., Winslow, K.H., and Folt, C.L., 2008, Do native species limit survival of 

reintroduced Atlantic salmon in historic rearing streams?: Biological Conservation, v. 141, p. 

146-152. 

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24
 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill

Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

G

o

d’s

P

ocket Cr.

Unnamed Trib.

Nevada

EXPLANATION

Nevada

Idaho

- 41 ۫N

- 36 ۫N

120 ۫W -

114 ۫W -

Figure 1. Map of the East and West Forks of the Jarbidge River, Idaho and Nevada, with the locations of 

reported fish barriers and passive integrated transponder (PIT) tag interrogations systems installed in 2006 

or 2007. 

25
Figure 2. Locations of fish and habitat surveys, fish barriers, and passive integrated transponder (PIT) tag 

interrogation systems in the West Fork Jarbidge River, Nevada, and its tributaries, 2006 and 2007. The 

interrogation systems at the confluence of Pine Creek and West Fork Jarbidge River, Nevada, and at the 

confluence of the East Fork and West Fork Jarbidge River, Idaho, were not installed until 2007. 

Jarbidge

e

Ri

ver

Jack Cr.

Pine

Cr.

Deer Cr.

Buck Cr.

West Fork Jarbidge River

West Fo

rk

J

arbid

g

2006 sampling area

2007 sampling area

PIT tag interrogator

Fish barrier

EXPLANATION

0 234 1 km

26
Figure 3. Locations of fish and habitat surveys, fish barriers, and passive integrated transponder (PIT) tag 

interrogation systems in the East Fork Jarbidge River, Nevada, and its tributaries, 2006 and 2007. The 

interrogation systems on Dave Creek, Nevada, and at the confluence of the East Fork and West Fork 

Jarbidge River, Idaho, were not installed until 2007. Da

East Fork Jarbidg

Murphy Hot Springs

ve Cr.

Slide Cr.

e River

Fall Cr.

Cougar Cr.

East Fork Jarbidge River

2006 sampling are

0 234 1 km

God’s

Poc

ket Cr.

Unnamed Trib.

a

2007 sampling area

PIT tag interrogator

Fish barrier

EXPLANATION

27
28

Figure 4. Length frequency, in 2-mm increments, of all bull trout sampled in the West Fork Jarbidge River, 

Nevada, in 2006 and 2007. The horizontal lines indicate the growth of individual fish that were tagged in 

2006 and recaptured in 2007. The median number of days between tagging and recapture are shown in 

parentheses. Sampling effort is not the same for each year. The symbol “+” indicates the fork length of 

fish at tagging that were detected at an interrogation site after tagging. Vertical arrows indicate the break 

between age-0, age-1, and age-2 or older bull trout. 

Fork Length (m m )

20406080

100120140160180200220240260280300320340360

Frequency

0

2

4

6

8

1 0

1 2

1 4

1 6

= T agging dates: J

0

2

4

6

8

1 0

1 2

1 4

1 6

ul 06

 

= R ecapture dates: Jul - A ug 07 (390 days)

 

Jul-A ug 06

 Jun 07

Frequency

Jun 07

Jul - Aug 06 (333 days) 
29

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 8500 9000 9500 

Number of fish per meter

-1.5-1.0-0.5

0.00.5

W est Fork Jarbidge 2006

Length (m)

Figure 5. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) antrout and redband trout (RBT) per meter by size class in pools only (lower graph) in West Fork Jarbidge River (rkm 21.5 – 30

-0.1

0.00.10.20.30.40.50.6

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or R

< 200 mm BLT, 

> 200 mm BLT, 

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
Figure 6. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) an

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in West Fork Jarbidge River (rkm 21.7 – 32

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 

Number of fish per meter

-6-5-4-3-2-1

01

30

West Fork Jarbidge 2007

Length (m)

-0.2

0.00.20.40.60.81.0

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or RBT

< 200 mm BLT, <1

> 200 mm BLT, >1

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
31

Fork Length (mm)

20406080

100120140160180200220240260280300320340360380400

0

1

2

3

4

5

6

7

8

9

10

Frequency

0

10

20

30

40

50

60

= Tagging date: Jul 06 = Recapture date: Aug 07 (397 days)

Jul 06

Aug 07

Frequency

Figure 7. Length frequency ,in 2-mm increments, of all bull trout sampled in Pine Creek of the West Fork 

Jarbidge River subbasin, Nevada in 2006 and 2007. The horizontal lines indicate the growth of individual 

fish that were tagged in 2006 and recaptured in 2007. The mean number of days between tagging and 

recapture are shown in parentheses. The symbol “+” indicates the fork length of fish at tagging that were 

detected at an interrogation site after tagging. Vertical arrows indicate the break between age-0, age-1, or 

age-2 or older bull trout. 
32

0 500 1000 1500 2000 2500 

Number of fish per meter

-3.5-3.0-2.5-2.0-1.5-1.0-0.5

0.00.5

Cougar Creek 2007

Length (m )

Figure 8. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) antrout and redband trout (RBT) per meter by size class in pools only (lower graph) in Pine Creek (rkm 0 – 6.5), Nevada, 2006. 

-0.1

0.00.10.20.30.40.5

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude

N S N SN S N S

Age-0 BLT or RBT

< 200 mm BLT, <150 mm RBT> 200 mm BLT, >150 mm RBT
33

Figure 9. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) antrout and redband trout (RBT) per meter by size class in pools only (lower graph) in Pine Creek (rkm 0 – 5.9), Nevada, 2007. 

0 500 1000 1500 2000 2500 3000 3500 4000 

Number of fish per meter

-5-4-3-2-1

01

Pine Creek 2007

Length (m)

-0.6-0.4-0.2

0.00.20.40.60.81.01.2

Age-1 and older bull trout in all habitat units

Bull trout in pools onlyRedband trout in pools only

Age-0 BLT or RB

< 200 m m BLT, 

> 200 m m BLT, 

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
34

Fork Length (m m )

20406080

100120140160180200220240260280300320

Frequency

0

2

4

6

8

1 0

1 2

 Sep 06

= T agging date: S ep 06 = R ecapture dates: Aug 07 (332 days)

Frequency

0

2

4

6

8

1 0

1 2

 Aug 07

Figure 10. Length frequency in 2-mm increments of all bull trout sampled in Jack Creek of the West Fork 

Jarbidge River, Nevada, in 2006 and 2007. The horizontal lines indicate the growth of individual fish that 

were tagged in 2006 and recaptured in 2007. The number of days between tagging and recapture are 

shown in parentheses. The symbol “+” indicates the fork length of fish at tagging that were detected at an 

interrogation site after tagging. Vertical arrows indicate the break between age-0, age-1, and age-2 or older 

bull trout
35

0 500 1000 1500 2000 2500 3000 3500 4000 4500 

Number of fish per meter

-4-3-2-1

012

Jack Creek 2006

Length (m)

Figure 11. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Jack Creek (rkm 0 – 4.3), Nevada, 2006. 

-0.5

0.00.51.01.52.0

Age-1 and older bull trout in all habitat units

Bull trout in pools onlyRedband trout in pools only

Age-0 BLT or 

< 200 m m BLT

> 200 m m BLT

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
36

0 500 1000 1500 2000 2500 3000 3500 4000 450

Number of fish per m

Figure 12. Number of bull trout (BLT) per meter, by size class, for all habitat units sampled along with altitude (upper graph) trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Jack Creek (rkm 0 – 5.4), Nevada, 2007. 

eter 

-6-5-4-3-2-1

012

Jack Creek 2007

Length (m )

-1.0-0.5

0.00.51.01.52.02.5

A ge-1 and older bull trout in all habitat units

B ull trout in pools only

R edband trout in pools only

Age-0 BLT or RBT

< 200 m m BLT , <1

> 200 m m BLT, >1

A ge-0 bull trout in all habitat units

< 200 mm

> 200 mm 

A ltitude
37

Fork Length (mm)

20406080

100120140160180200220240260280300320340360380400

Frequency

Figure 13. Length frequency in 2-mm increments of all bull trout sampled in the East Fork Jarbidge River, 

Nevada, in 2006 and 2007. Sampling effort is not the same for each year. Vertical arrows indicate the 

break between age-0, age-1, and age-2 or older bull trout. The symbol “+” indicates the fork length of a fish 

that was recaptured in the East Fork Jarbidge River after being tagged in Fall Creek in 2006. 

0

2

4

6

8

10

12

14

16

18

20

0

2

4

6

8

10

12

14

 Jul 07

Frequency

 Aug 06
38

Figure 14. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in East Fork Jarbidge River (rkm 15.6 – 24.not sampled. 

N S

N S

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 

Number of fish per meter

-1.5-1.0-0.5

0.00.5

East Fork Jarbidge 2006

Length (m )

0 .00 .1

0.20.30.4

-0.1

A ge-1 and older bull trout in all habitat units

Bull trout in pools only

R edband trout in pools only

Age-0 BLT or R

< 200 m m BLT> 200 m m BLT

Age-0 bull trout in all habitat units

< 200 mm> 200 mm A ltitude
Figure 15. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in East Fork Jarbidge River (rkm 32.5 – 35.

0 500 1000 1500 2000 25

Number of fish per meter

-1.5-1.0-0.5

0.00.51.0

39

East Fork Jarbidge 2007

Length (m)

-0.2

0.00.20.40.60.81.01.21.4

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or RBT

< 200 mm BLT, <150 mm > 200 mm BLT, >150 mm 

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
40

20406080

100120140160180200220240260280300320340360

Frequency

0

1

2

3

4

5

6

East Fork Jarbidge unnamed tributary

13 Jul 07

Frequency

0

1

2

3

Cougar Creek

0

11-12 Jul 07

Figure 16. Length frequency in 2-mm increments of all bull trout sampled in Cougar Creek, Nevada, and an 

unnamed tributary of the East Fork Jarbidge River, Nevada, at rkm 33.5 (measured from the confluence 

with the West Fork Jarbidge River, Idaho), 2007. 
41

Figure 17. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) atrout and redband trout (RBT) per meter by size class in pools only (lower graph) in Cougar Creek (rkm 0 – 3.1), Nevada, 200

0 500 1000 1500 2000 2500 

Number of fish per meter

-3.5-3.0-2.5-2.0-1.5-1.0-0.5

0.00.5

Cougar Creek 2007

Length (m )

-0.1

0.00.10.20.30.40.5

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude

N S N SN S N S

Age-0 BLT or RBT

< 200 m m BLT, <150 m m RBT> 200 m m BLT, >150 m m RBT
42

Fork Length (mm)

20406080

100120140160180200220240260280300320340360380400

Frequency

0

1

2

3

4

5

6

20 Aug 06

Frequency

0

1

2

3

4

15 Jul 07

Figure 18. Length frequency in 2-mm increments of all bull trout sampled in Fall Creek of the East Fork 

Jarbidge River, Nevada, in 2006 and 2007. Sampling effort is not the same for each year. Vertical arrows 

indicate the break between age-0, age-1, and age-2 or older bull trout. The symbol “+” indicates the fork 

length of a fish that had moved and subsequently recaptured in the East Fork Jarbidge downstream of the 

confluence with Slide Creek.
43

Figure 19. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Fall Creek (rkm 0 – 2.0), Nevada, 2006. 

0 500 1000 1500 2000

Number of fish per meter

-2.0-1.5-1.0-0.5

0.0

Fall Creek 2006

Length (m)

-0.1

0.00.10.2

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or RBT

< 200 m m BLT, <150 m m RBT> 200 m m BLT, >150 m m RBT

Age-0 bull trout in all habitat units

< 200 mm> 200 mm 

Altitude
Figure 20. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Fall Creek (rkm 1.4 – 3.2), Nevada, 2007

0 500 1000 1500

Number of fish per meter

-2.5-2.0-1.5-1.0-0.5

0.00.5

44

Fall Creek 2007

Length (m)

-0.2

0.00.20.40.60.8

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or RB

< 200 mm BLT, <> 200 mm BLT, >

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
Figure 21. Length frequency in 2-mm increments of all bull trout sampled in Slide Creek of the East Fork 

Jarbidge River, Nevada, in 2006 and 2007. Sampling effort is not the same for each year. 

Fork Length (mm)

20406080

100120140160180200220240260280300320

Frequency

0

1

2

3

4

5

0

1

2 Jul 07

Frequency

Aug 06

45
46

Figure 22. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Slide Creek (rkm 0 – 5.5), Nevada, 2006

N S N S

N S N S

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 550

Number of fish per meter

-1.6-1.4-1.2-1.0-0.8-0.6-0.4-0.2

0.00.2

Slide Creek 2006

Length (m)

-0.1

0.00.10.2

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only Age-0 BLT or R

< 200 m m BLT

> 200 m m BLT

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
Figure 23. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Slide Creek (rkm 4.6 – 7.7), Nevada, 200

NSNS

0 500 1000 1500 2000 2500 

Number of fish per meter

-7-6-5-4-3-2-1

01

Slide Creek 2007

Length (m)

47

-0.1

0.00.10.2

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or RB

< 200 mm BLT, <

> 200 mm BLT, >

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude 
48

Fork Length (mm)

405060708090

100110120130140150160170180190200210220230240250260

Frequency

0

2

4

6

8

10

12

Frequency

0

2

4

6

8

10

12

28 Jun - 2 Jul 07

6 Sep 07

 Aug 06

Frequency

0

2

4

6

= Tagging dates: Jun -Jul 07 = Recapture date: Sep 07 (68 days)

 = Tagging date: Aug 06 = Recapture date: Jun 07 (327 days)

Jun-Jul 07

Sep 07

Figure 24. Length frequency in 2-mm increments of all bull trout sampled in Dave Creek of the East Fork 

Jarbidge River, Nevada, in summer 2006, early summer 2007, and late summer 2007. The horizontal lines 

indicate the growth of individual fish that were tagged in 2006 and recaptured in early summer 2007, and 

those that were tagged early summer 2007 and recaptured late summer 2007. The number of days 

between tagging and recapture are shown in parentheses. The symbol “+” indicates the fork length of fish 

at tagging that were detected at an interrogation site after tagging. Vertical arrows indicate the break 

between age-0, age-1, and age-2 or older bull trout. 
49

0 500 1000 1500 2000 2500 3000 3500 4000 4

Number of fish per meter

-3.0-2.5-2.0-1.5-1.0-0.5

0.00.51.0

Dave Creek 2006

Length (m)

Figure 25. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Dave Creek (rkm 6.8 – 11.7), Nevada, 20

-0.2

0.00.20.40.60.81.0

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only

Age-0 BLT or 

< 200 m m BLT> 200 m m BLT

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
50

Figure 26. Number of bull trout (BLT) per meter by size class for all habitat units sampled along with altitude (upper graph) a

trout and redband trout (RBT) per meter by size class in pools only (lower graph) in Dave Creek (rkm 6.8 – 14.0), Nevada, 20

0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 

Number of fish per meter

-2.0-1.5-1.0-0.5

0.00.51.01.52.0

Dave Creek 2007

Length (m)

-0.5

0.00.51.01.52.0

Age-1 and older bull trout in all habitat units

Bull trout in pools only

Redband trout in pools only Age-0 BLT or R

< 200 m m BLT> 200 m m BLT

Age-0 bull trout in all habitat units

< 200 mm> 200 mm Altitude
Figure 27. Operational status of interrogation systems during 2007 in the Jarbidge River subbasin, Idaho 

and Nevada. Maybe indicates that although the system was operational, the distance at which a tag could 

be detected may have been reduced due to low battery voltage.

EFJ

Yes

Maybe

No

Jack Creek

Yes

Maybe

No

WFP

Yes

Maybe

No

WFJ

Yes

Maybe

No

Dave Creek

Yes

Maybe

No

Forks

Date

Yes

Maybe

No

Apr/07 

May/07 

Jun/07 

Jul/07

Aug/07 Sep/07 

Oct/07 

Nov/07 

Dec/07 

Jan/08 

51
52

 

Figure 28. Number and movement direction of PIT tagged bull trout by month detected at the interrogation 

site in the East Fork Jarbidge River (EFJ, rkm 4.1), Idaho, and at the East Fork Jarbidge River and West 

Fork Jarbidge River (Forks, rkm 0.1) interrogation sites, Idaho, during 2007. 

Month

Apr May Jun Jul Aug Sep Oct Nov Dec Jan

Interrogations

-4

-2

0

2

4

EFJ = East Fork Jarbidge (rkm 4.1)

EFC = East Fork Conflunce (rkm 0.1)

WFC = West Fork Confluence (rkm 0.1) Unknown

Upstream

Downstream

EFJ

EFC

WFC

EFJ

WFC

WFC
53

Date

Apr M ay Jun Jul Aug Sep O ct Nov Dec Ja

Flow (cubic feet per second)

0

50

100150200250

W FJacW F

Flow (cfs)

Jack Ck. (rkm 0.1) W FJ (rkm 16.5W FJ (rkm 28.8)

Tem perature

Figure 29. Streamflow (cfs), temperature, and direction of PIT tagged bull trout movements detected at interrogation sites in River (rkm 15), Jack Creek (rkm 0.1), and West Fork Jarbidge and Pine Creek confluence (rkm 26), Nevada, 2007. Triangles upstream movement, and triangles pointing down indicate downstream movement. Stream flow measurements were taken fr

on the West Fork Jarbidge River (WFJ, rkm 19.2). Temperatures were taken at rkm 0.1 in Jack Cr., rkm 16.5 of the West For

Jack Cr., and rkm 28.8 in the West Fork Jarbidge River at Snowslide Gulch by BLM. 
Figure 30. Time of day that PIT tagged bull trout passed any interrogation system in the Jarbidge River subbasin, Idaho and 

2007.

54

02468

10

0:001:002:003:004:005:006:007:008:009:0010:0011:0012:0013:0014:0015:0016:0017:0018:0019:0020:0021:00

Time

Frequency

121416
Table 1. Number of bull trout the captured by electrofishing and PIT tagged in the East and West Forks of 

the Jarbidge River watershed in 2006. 

[See figure 3 for additional information on sampling locations. Start and end river kilometer (rkm) were estimated 

with GPS positions and mapping software. All fish tagged in 2006 were tagged with 12-mm 134.4Khz PIT tags. 

Bolded numbers represent combined totals by stream for each sampling effort] 

Watershed 

 Stream or section

Sampling 

dates 

Rkm 

(start) 

Rkm 

(end) 

Bull 

trout 

captured 

PIT tags 

deployed 

Genetic 

samples 

collected 

West Fork Jarbidge River (WFJ)

 Gorge Gulch to just below Sawmill Cr. (WFJ) 7/19-7/22 27.0 30.2 76 73 41 

 Pine Cr. Campground to Gorge Gulch (WFJ) 8/07, 10/04 23.5 27.0 7 7 5 

 Bourne Gulch to Pine Cr. campground (WFJ) 9/24-9/26 22.0 23.5 13 13 13 

 Instream interrogation site (WFJ) 9/23-9/24 14.5 15.5 1 1 1 

Mainstem WFJ subtotal 97 94 60

 Pine Creek 7/23-9/26 0 6.5 27 25 25 

 Jack Creek 9/08-9/11 0 4.3 70 66 59 

WFJ total 20.0 194 185 144 

East Fork Jarbidge River (EFJ)

 Dave Creek 8/03-8/06 6.8 11.7 129 111 67 

 Mainstem wilderness (EFJ) 8/17-8/19 15.6 24.7 13 13 13 

 Above Murphy Hot Springs (EFJ) 10/03 4.1 4.9 0 0 0 

 Fall Creek 8/20 0 2.0 9 9 9 

 Slide Creek 4 4 4 

 Confluence with EFJ 8/21 0 2.9 0 0 0 

 Middle 8/22 3.1 4.6 2 2 2 

 Upper 8/22 5.4 5.5 2 2 2 

EFJ total 19.9 155 137 93 

WFJ and EFJ combined total 39.9 349 322 237 

55 
Table 2. Number of bull trout captured by electrofishing and PIT tagged in the West Fork Jarbidge River 

subbasin in 2007. 

[See figure 2 for additional information on sampling locations. Start and end river kilometer (rkm) were estimated 

with GPS positions and mapping software. All fish tagged in 2007 were tagged with 12-mm 134.4Khz PIT tags. 

Bolded numbers represent combined totals of each sampling effort] 

Watershed 

 Stream or section

Sampling 

dates 

Rkm 

(start) 

Rkm 

(end) 

Bull 

trout 

captured 

PIT tags 

deployed 

Recaptured 

bull trout 

from 2006 

Genetic 

samples 

collected 

West Fork Jarbidge River (WFJ)

 WFJ 6/13-6/14 

6/20-6/22 

6/26, 8/02 

8/14-8/15 

21.7 32.2 272c 258 6 24 

 Pine Creek 8/16, 8/21-

8/23, 8/27, 

8/29 

0 5.9 430 380 5 97 

 Jack Creek 

 Marking sampling effort 8/06-8/07, 

8/09 

0 5.4 93 70 9 78 

 Recapture sampling effort 8/08, 8/10 0 5.4 53a 31 1b 28 

 Jack Creek subtotal 146 101 10 b 106 

 Deer Creek 9/10 6.9 9.4 0 0 0 0 

 Buck Creek 9/14 

 Below private property 3.6 3.8 0 0 0 0 

 Above private property 12.7 13.1 0 0 0 0 

 Buck Creek subtotal 0 0 0 0 

WFJ total 24.9c 848 739 21 227 

a Twenty-three bull trout were recaptured from the marking sampling effort the previous day and were not included. b The number of recaptured bull trout does not include fish that were tagged and recaptured within 2007.

c Distance does not include areas that were re-sampled. 

56
57

Table 3. Number of bull trout captured by electrofishing and PIT tagged in the East Fork Jarbidge River 

subbasin in 2007. 

[See figure 3 for additional information on sampling locations. Start and end rkm were estimated with GPS 

positions and mapping software. All fish tagged in 2007 were tagged with 12-mm 134.4Khz PIT tags. The number 

of recaptured bull trout does not include fish that were tagged and recaptured within 2007. Bolded numbers 

represent combined totals by stream for each sampling effort] 

Watershed 

 Stream or section

Sampling 

dates 

Rkm 

(start) 

Rkm 

(end) 

Bull 

trout 

captured 

PIT tags 

deployed 

Recaptured 

bull trout 

from 2006 

Genetic 

samples 

collected 

East Fork Jarbidge River (EFJ)

 EFJ 

 Below Slide Cr. to Slide Cr. 7/17 23.0 23.5 1 0 1 1 

 Wilderness (rkm 32.5) 7/12-7/14 32.5 35.0 323 312 0a 203 

 Unnamed East Fork tributary 7/13 0 0.3 13 12 0 8 

 EFJ subtotal 337 324 1 212 

 Cougar Creek 

 Confluence with EFJ 7/11 0 0.7 0 0 0 0 

 Site 2 7/11 1.2 1.5 1 1 0 1 

 Site 3 to barrier 7/11-7/12 1.8 3.1 6 6 0 6 

 Cougar Creek subtotal 7 7 0 7 

 Fall Creek 7/15 1.4 3.2 30 30 0 30 

 Slide Creek 

 Site 1 7/16 4.6 5.7 1 1 0 1 

 Site 2 to barrier 7/16-7/17 5.8 7.7 2 2 0 2 

 Slide Creek subtotal 3 3 0 3 

 Gods Pocket Creek 7/17 0.6 0.9 0 0 0 0 

 Dave Creek 

 Initial sampling effort 6/28-7/02 6.8 14.0 105 100 3 81 

 Recapture sampling effort 9/11 10.5 13.9 23 11 0b 8 

 

Dave Creek subtotal

128 111 3 89 

EFJ total 17.8 c 505 475 4 342 

EFJ and WFJ combined total 42.7 c 1,353 1,214 25 569 

a

 Nine bull trout were recaptured from previous day of 2007 sampling in Wilderness and were not included. 

b Seven bull trout were recaptured from initial 2007 sampling of Dave Creek and were not included. c Distance does not include areas that were re-sampled. 
Table 4. Location, altitude and estimated length of fish and habitat surveys conducted in the Jarbidge River watershed during 

[See figures 2 and 3 for additional information on sampling locations. Altitudes were obtained using Google® Earth as altitudes given 

accurate. Estimated length was calculated by summing the visually estimated lengths of each habitat unit] _____________________________________________________________________________________________________________ GPS reading GPS reading Altitude (m) Watershed Start of reach End of reach ______________

 Stream or section North West North West SOR EO

_____________________________________________________________________________________________________________West Fork Jarbidge River  All sites combined 41°55’49.8” 115°25’04.3” 41°48’07.8” 115°24’12.1” 1,753 2,2

 Gorge Gulch - below Sawmill Creek 41°49’56.5” 115°25’17.9” 41°48’07.8” 115°24’12.1” 2,062 2,2 Pine Creek camp - Gorge Gulch 41°50’03.1” 115°25’30.6” 41°50’03.7” 115°25’38.6” 2,039 2,0 Bourne Gulch - Pine Creek camp 41°52’09.2” 115°25’58.6” 41°50’03.1” 115°25’30.6” 1,890 2,0 Antenna site 41°55’49.8” 115°25’04.3” 41°54’54.1” 115°25’27.8” 1,753 1,8 Pine Creek 41°50’03.1” 115°25’30.6” 41°47’05.4” 115°27’27.4” 2,039 2,3 Jack Creek 41°54’39.2” 115°25’22.6” 41°53’23.7” 115°23’07.7” 1,673 2,1East Fork Jarbidge River  All sites combined RNTa 41°47’30.0” 115°19’21.8” RNT 2,2 Above Murphy RNT RNT RNT RN Wilderness 41°51’59.6” 115°18’45.8” 41°47’30.0” 115°19’21.8” 1,962 2,2 Slide Creek 41°52’00.0” 115°18’45.9” 41°50’16.1” 115°15’59.8” 1,958 2,2 Fall Creek 41°51’22.6” 115°18’52.8” RNT 1,944 2,0 Dave Creek 41°56’27.0” 115°22’08.9” 41°54’00.3” 115°20’58.7” 1,986 2,2

Total length su

_____________________________________________________________________________________________________________a RNT=GPS reading not taken because of topography of basin. Values were estimated from Google® Earth. 

58 
Table 5. Location, altitude and estimated length of fish and habitat surveys conducted in the Jarbidge River watershed during 

[See figures 2 and 3 for additional information on sampling locations. Altitudes were obtained using Google® Earth as altitudes given baccurate. Estimated length was calculated by summing the visually estimated lengths of each habitat unit] 

GPS reading 

Start of reach 

GPS reading 

End of reach Watershed Al

 Stream or section North West North West SOR West Fork Jarbidge River (WFJ)  WFJ 41°52’09.9” 115°25’55.2” 41°47’34.4” 115°23’47.3” 1,90

 Pine Creek 41°50’03.4” 115°25’31.1” 41°47’24.8” 115°27’00.5” 2,00

 Jack Creek 41°54’43.1” 115°25’29.0” 41°52’53.1” 115°22’47.5” 1,79 Deer Creek 41°52’43.8” 115°27’07.5” 41°51’42.0” 115°28’01.6” 2,14

 Buck Creek

 Below private property 41°58’28.2” 115°25’44.1” 41°58’52.2” 115°25’57.6” 1,83

 Above private property 41°54’40.5” 115°28’52.1” 41°54’32.0” 115°29’01.3” 2,04

East Fork Jarbidge River (EFJ)

 EFJ below Slide Creek to Slide Creek confluence 41°52’10.7” 115°18’48.4” 41°51'59.2" 115°18'45.5" 1,93 Upper EFJ 41°47’26.5” 115°19’21.6” 41°46’59.9” 115°20’45.1” 2,24 Cougar Creek  Confluence with EFJ 41°50’24.3” 115°19’12.8” 41°50’19.8” 115°19’38.9” 2,00

 Site 2 41°50’04.4” 115°19’47.9” 41°49’52.5” 115°19’52.7” 2,07

 Site 3 to barrier 41°49’44.9” 115°19’55.8” 41°49’04.3” 115°20’10.1” 2,12

 Dave Creek 41°56’26.9” 115°22’09.1” 41°52’56.0” 115°21’18.9” 1,99

 Fall Creek 41°50’55.5” 115°19’38.2” 41°50’11.8” 115°20’19.1” 2,02

 Slide Creek 

 Site 1 41°50’22.2” 115°16’37.9” 41°50’18.1” 115°15’58.6” 2,17 Site 2 to barrier 41°50’18.9” 115°15’52.6” 41°51’04.8” 115°15’12.5” 2,24 Gods Pocket Creek 41°50’37.1” 115°17’46.1” 41°50’26.6” 115°17’51.0” 2,12

 Unnamed East Fork Tributary 41°46’56.7” 115°19’46.4” 41°46’46.4” 115°19’47.9” 2,31

59
Table 6. Number (n) of bull trout captured, the sampling distance (rkm), the number of bull trout 

captured with a fork length greater than 200 mm, the number of bull trout with a fork length greater 

than 250 mm, the minimum (min) fork length, the maximum (max) fork length, and weight of bull 

trout for each creek sampled in the Jarbidge River watershed, Nevada, in 2006-2007. 

[The number of fish captured does not include fish that were tagged and recaptured within 2007. Figures 2 

and 3 contain additional location information. River kilometer (rkm) was estimated, using mapping 

software, from a start point of the confluence of the East Fork and West Fork Jarbidge River, or for 

tributaries, the confluence with East Fork or West Fork Jarbidge River] 

Watershed River kilometer 

(rkm) No. with fork length Fork length 

 (mm) 

Weight 

(g) 

 Stream (start) (end) n >200mm >250mm min max min max 

West Fork Jarbidge River (WFJ)-2006

 WFJ a 14.5 30.2 97 11 3 23 330 0.3 508.0 

 Pine Cr. 0 6.6 27 6 0 39 243 0.7 161.0 

 Jack Cr. 0 4.3 70 8 3 61 310 2.5 268.0 

Total 194 25 6 

West Fork Jarbidge River (WFJ)-2007

 WFJ 24.8 32.2 272 19 3 28 273 3.6 222.8 

 Pine Cr. 0 5.9 430 12 3 55 387 1.8 650.3 

 Jack Cr. 0 5.4 146 14 2 42 283 1.0 230.8 

Total 848 45 8 

East Fork Jarbidge River (EFJ)-2006

 EFJ 16.0 22.6 13 5 1 135 260 22.4 194.5 

 Dave Cr. 6.8 11.7 129 16 0 97 229 9.3 148.0 

 Fall Cr. 0 2.0 9 0 1 119 360b 16.1 440.6 

 Slide Cr. a 0 2.1 4 0 1 189 300 62.8 230.2 

 Total 155 21 3 

East Fork Jarbidge River (EFJ)-2007

 EFJ a 23.0 35.0 324 63 8 78 400b 4.7 767.2 

 Dave Cr. 6.8 14.0 128 7 0 59 232 1.8 145.4 

 Fall Cr. 1.4 3.2 30 4 0 79 247 4.8 196.9 

 Slide Cr. a 4.6 7.7 3 1 0 95 220 8.7 122.7 

 Cougar Cr.

a

0 3.1 7 

 4 2 138 340 26.5 420.4 

 EFJ Trib. 0 0.3 13 6 0 130 238 20.7 176.9 

Total 505 85 10 

a

 River kilometer represents the overall range of where sampling occurred. The entire distance was not 

completely sampled, as certain sections of river were skipped; see figures 2 and 3 for details. b

 Largest fish captured in Fall Ck. in 2006 and the largest fish captured in the East Fork Jarbidge River in 

2007 was the same fish. 

60
Table 7. Number (n) of bull trout (BLT) collected, survey length, percent of stream length with bull 

trout, the percent of habitat units with at least one bull trout, the percent of stream length that was 

pool-like, and percent of bull trout found in pools in the Jarbidge River watershed in 2006-2007. 

[River kilometer was estimated, using mapping software, from a start point of the confluence of the East 

Fork and West Fork Jarbidge River, or for tributaries, the confluence with either the East Fork or West 

Fork Jarbidge River. Habitat units were defined as either pool or non-pool] 

Watershed River kilometer 

 Stream n (start) (end) 

Survey 

length (m) 

% length 

with BLT 

% habitat 

units with 

BLT 

% length 

identified 

as pools 

% BLT in 

pools 

West Fork Jarbidge River (WFJ)-2006

 WFJ a 97 14.5 30.2 12,856 20 21 16 20 

 Pine Cr. 27 0 6.6 5,530 21 14 10 30 

 Jack Cr. 70 0 4.3 5,224 24 29 10 44 

West Fork Jarbidge River (WFJ)-2007

 WFJ 272 24.8 32.2 8,872 37 50 12 15 

 Pine Cr. 430 0 5.9 4,490 57 83 9 10 

 Jack Cr. 146 0 5.4 5,347 27 45 8 39 

East Fork Jarbidge River (EFJ)-2006

 EFJ 13 16.0 22.6 8,003 8 5 19 25 

 Dave Cr. 129 6.8 11.7 4,903 38 46 7 15 

 Fall Cr. 9 0 2.0 2,311 15 8 14 22 

 Slide Cr. a 4 0 2.1 4,625 3 3 12 0 

 

East Fork Jarbidge River (EFJ)-2007

 EFJ a 324 23.0 35.0 3,297 52 83 13 19 

 Dave Cr. 128 6.8 14.0 6,340 41 62 2 10 

 Fall Cr. 30 1.4 3.2 1,675 26 28 9 20 

 Slide Cr. a 3 4.6 7.7 3,066 3 3 4 0 

 Cougar Cr. a 7 0 3.1 2,612 6 4 16 71 

 Unnamed Trib. 13 0 0.3 248 63 72 5 0 

a

 River kilometer represents the overall range of where sampling occurred. The entire distance was not 

completely sampled, as certain sections of river were skipped; see figures 2 and 3 for more detail. 

61
Table 8. Location and installation date of passive integrated transponder (PIT) tag interrogation 

units installed in the Jarbidge River watershed in 2006-2007, and the number of bull trout (BLT) 

interrogated by tagging location in 2006-2007. 

[River kilometer was estimated, using mapping software, from a start point of the confluence of the East 

Fork and West Fork Jarbidge River, or for tributaries, the confluence with either the East Fork or West 

Fork Jarbidge River. The 4 out of 8 tagging streams listed were the only ones that had fish detected at the 

interrogators. Fish detected on more than one array are counted more than once] 

No. of BLT detected by tagging stream Watershed 

 Interrogation site Start date 

River 

kilometer WFJ EFJ 

WFJ Pine Cr. Jack Cr. Dave Cr. 

West Fork Jarbidge River (WFJ) - 2006

 Jack Creek 9/15/2006 0.1 0 0 1 0 

 WFJ downstream of Jack Cr. 9/15/2006 15.0 3 1 1 0 

West Fork Jarbidge River (WFJ) - 2007

 WFJ at Pine Creek 7/16/2007 26.2 20a 8b 0 0 

 Pine Creek at WFJ 7/16/2007 0.1 11 8b 0 0 

 Jack Creek 4/18/2007 0.1 0 0 7 0 

 WFJ downstream of Jack Cr. 4/28/2007 15.0 1 0 2 0 

 WFJ at Forks 7/17/2007 0.1 0 0 3c 1c 

East Fork Jarbidge River (EFJ) - 2006

 EFJ at Murphy Hot Springs 9/15/2006 4.1 0 0 0 0 

East Fork Jarbidge River (EFJ) - 2007

 Dave Creek 5/23/2007 0.4 0 0 0 0 

 EFJ at Murphy Hot Springs 4/28/2007 4.1 0 0 1 1 

 EFJ at Forks 7/17/2007 0.1 0 0 2c 1c 

Total unique fish - 2006 3 1 1 0 

Total unique fish - 2007 24 9 9 2 

z Eighteen of these 20 fish were interrogated moving downstream. The West Fork Jarbidge River/Pine Cr. 

PTIS detected a fish on the first day of installation. d

 Seven of these 8 fish were interrogated moving out of Pine Creek and downstream in the West Fork 

Jarbidge River between 7 Oct. 2007 and 4 Nov. 2007. e One fish from Jack Creek and one from Dave Creek were detected at both the East Fork and West Fork 

Jarbidge River antennas at the Forks, see figures A2 and A10 for details. 

62
Table 9. Stream discharge in the Jarbidge River watershed on sampling dates in 2007. 

 

[ Discharge measurements were taken at passive integrated transponder tag interrogation unit (PTIS) sites] 

Discharge, in cubic feet per second Subbasin 

 Stream and location 8/1/07 8/13/07 8/20/07 

West Fork Jarbidge River (WFJ)

 Mainstem Jarbidge River below the Forks (rkm 46.6) 30.75 not taken 9.33 

 WFJ above PTIS (rkm 15.0) 7.86 6.25 4.73 

 Jack Creek below PTIS (rkm 0.1) 1.39 1.07 0.77 

 WFJ below Pine Creek (rkm 26.2) 5.42 3.89 3.60 

 Pine Creek above PTIS (rkm 0.1) 2.44 0.80 1.17 

East Fork Jarbidge River (EFJ) 

 EFJ above PTIS (rkm 4.1) 18.78 not taken 4.84 

 Dave Creek above PTIS (rkm 0.4) 0.56 0.38 0.25 

63
Appendix table and figures 

Appendix Table A1. Temperatures (oC) collected with a hand held thermometer while 

electrofishing in the upper Jarbidge River subbasin, Nevada, during 2006 and 2007. 

[Please see tables 1-4 and figures 2 and 3 for specific location information] 

Site Date 

Morning 

(8:00am-11:30am) 

Mid 

(11:30am -2:00pm) 

Afternoon 

(2:00pm-5:00 pm) 

Buck Cr. 9/14/2007 9.0 14.0 

Cougar Cr. 7/11/2007 12.5 

7/12/2007 11.5 15.5 

Dave Cr. 8/03/2006 14.0 

8/04/2006 15.0 

8/05/2006 8.0 10.0 

8/06/2006 7.0 10.5 

6/28/2007 6.0 11.0 13.5 

6/29/2007 5.0 10.5 10.0 

6/30/2007 4.0 9.0 7.0 

7/01/2007 9.0 11.5 

7/02/2007 7.5 13.0 14.0 

9/06/2007 6.5 9.0 12.0 

Deer Cr. 9/10/2007 4.0 7.5 

East Fork Jarbidge 

River 8/17/2006 11.5 14.0 

8/18/2006 9.5 13.0 

8/19/2006 10.0 9.5 

7/12/2007 9.0 12.0 

7/13/2007 9.0 14.0 15.0 

7/14/2007 15.0 

Fall Cr. 8/20/2006 8.0 9.5 

7/15/2007 13.0 

Gods Pocket Cr. 7/17/2007 10.5 

Jack Cr. 9/08/2006 9.0 

9/09/2006 9.0 10.0 9.5 

9/11/2006 8.0 

8/06/2007 13.0 13.5 

8/07/2007 10.5 10.5 12.0 

8/08/2007 10.0 12.5 

8/09/2007 11.0 13.0 16.0 

8/09/2007 11.0 

8/10/2007 11.5 14.5 

9/11/2007 6.0 7.0 

Pine Cr. 7/23/2006 13.5 14.5 

7/24/2006 11.0 11.5 

7/25/2006 10.0 12.5 

7/26/2006 14.0 

Pine Cr. 8/21/2007 11.0 12.0 

64
Site Date 

Morning 

(8:00am-11:30am) 

Mid 

(11:30am -2:00pm) 

Afternoon 

(2:00pm-5:00 pm) 

8/22/2007 11.5 13.5 

8/23/2007 8.0 10.5 12.5 

8/27/2007 10.0 14.5 

8/29/2007 10.0 12.0 14.0 

Slide Cr. 8/21/2006 12.0 

8/22/2006 8.0 9.5 

7/16/2007 12.0 13.0 14.0 

West Fork Jarbidge 

River 7/19/2006 12.0 

7/20/2006 10.0 12.5 

7/21/2006 9.5 12.5 

7/22/2006 10.0 12.0 12.5 

8/07/2006 10.0 11.5 

9/23/2006 8.0 

9/24/2006 7.0 

9/25/2006 5.0 7.0 

10/04/2006 6.0 

6/11/2007 10.0 

6/13/2007 7.5 12.0 

6/14/2007 9.5 13.0 

6/20/2007 7.0 8.0 

6/21/2007 6.0 8.5 

6/22/2007 6.5 8.0 9.0 

6/26/2007 5.0 10.0 12.0 

6/27/2007 6.0 14.0 12.5 

8/02/2007 14.0 16.0 

8/14/2007 11.0 13.0 

8/15/2007 10.5 11.0 

65
Appendix Figures A1 – A50. Maps of tagging location and the timing and location of detection or 

recapture for all bull trout with noteworthy movements during 2006 and 2007 in the Jarbidge River 

subbasin, Nevada and Idaho. 

66
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (4/29/07)

1 (8/6/06)

Fish ID: 3D9.1BF2085C05

Fork Length (mm): 195

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/28/07)

2 (7/28/07)

Fish ID: 3D9.1C2C4890A1

Fork Length (mm): 164

A1 A2 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (9/9/06)

4 (6/11/07)

5 (6/12/07)

2 (10/7/06)

3 (10/8/06)

Fish ID: 3D9.257C67F36C

Fork Length (mm): 310

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (9/9/06)

2 (7/14/07)

3 (7/19/07)

4 (7/21/07)

Fish ID: 3D9.257C687006

Fork Length (mm): 175

A3 A4 

Figures A1 – A4. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information.

67
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (6/29/07)

3 (7/2/07)

1 (9/10/06)

Fish ID: 3D9.257C5B22F3

Fork Length (mm): 190

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (7/13/07)

1 (9/10/06)

3 (11/20/07)

Fish ID: 3D9.257C5D17A4

Fork Length (mm): 175

A5 A6 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (7/23/07)

2 (7/21/07)

1 (9/10/06)

Fish ID: 3D9.257C5B2A86

Fork Length (mm): 138

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (7/4/07)

3 (7/11/07)

1 (9/10/06)

Fish ID: 3D9.257C5CBCC1

Fork Length (mm): 172

A7 A8 

Figures A5 – A8. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

68
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (8/26/07)

1 (9/10/06)

3 (10/19/07)

Fish ID: 3D9.257C5B27D2

Fork Length (mm): 190

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr. 3 (7/26/07)

2 (7/20/07)

1 (9/10/06)

Fish ID: 3D9.257C5B2260

Fork Length (mm): 130

A9 A10 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/10/07)

2 (11/9/07)

Fish ID: 3D9.1C2C575B19

Fork Length (mm): 138

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (11/16/07)

1 (8/9/07)

Fish ID: 3D9.1C2C575C96

Fork Length (mm): 171

A11 A12 

Figures A9 – A12. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

69
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (10/30/07)

1 (7/25/06)

Fish ID: 3D9.257C5AD7E1

Fork Length (mm): 162

2 (8/27/07)

Recapture (mm): 200

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (11/3/06)

1 (7/25/06)

Fish ID: 3D9.257C5B1FCC

Fork Length (mm): 219

A13 A14 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (10/8/07)

1 (8/27/07)

Fish ID: 3D9.1C2C576338

Fork Length (mm): 200

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (10/30/07)

1 (8/29/07)

Fish ID: 3D9.1C2C599B67

Fork Length (mm): 350

A15 A16 

Figures A13 – A16. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

70
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (10/16/07)

1 (8/29/07)

Fish ID: 3D9.1C2C5735F5

Fork Length (mm): 179

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (10/7/07)

1 (8/21/07)

Fish ID: 3D9.1C2C57989D

Fork Length (mm): 145

A17 A18 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (11/4/07)

1 (8/22/07)

Fish ID: 3D9.1C2C573197

Fork Length (mm): 135

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (10/19/07)

1 (8/22/07)

Fish ID: 3D9.1C2C57E1E9

Fork Length (mm): 130

A19 A20 

Figures A17 – A20. Movement of PIT-tagged bull within the Jarbidge River subbasin in 2006 and 

2007. Each map represents a single bull trout and the number next to the symbol represents the 

order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information.

71
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (8/4/07)

4 (8/16/07) 5 (11/7/07)

1 (6/21/07)

Fish ID: 3D9.257C67FFA4

Fork Length (mm): 131

2 (7/31/07)

Recapture (mm): 149

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (10/19/07)

2 (8/29/07)

Fish ID: 3D9.257C5B2197

Fork Length (mm): 330

Recapture (mm): 387

1 (9/24/06)

A21 A22 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (5/7/07)

1 (9/25/06) 3 (9/3/07)

Fish ID: 3D9.257C5AC601

Fork Length (mm): 244

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (9/25/06) 2 (9/2/07)

Fish ID: 3D9.257C5AC17F

Fork Length (mm): 310

A23 A24 

Figures A21 – A24. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

72
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (9/25/06) 2 (9/30/07)

Fish ID: 3D9.257C5B1C6A

Fork Length (mm): 220

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (11/17/06)

1 (8/7/06)

Fish ID: 3D9.1BF20B9DCF

Fork Length (mm): 168

A25 A26 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (10/7/07)

1 (7/22/06)

2 (10/3/07)

Fish ID: 3D9.257C5AB8DA

Fork Length (mm): 174

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (7/22/06)

2 (11/20/06)

Fish ID: 3D9.257C5AFA62

Fork Length (mm): 147

A27 A28 

Figures A25 – A28. Movement of PIT-tagged bull within the Jarbidge River subbasin in 2006 and 

2007. Each map represents a single bull trout and the number next to the symbol represents the 

order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

73
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (7/22/06)

3 (11/7/07)

2 (6/20/07)

Fish ID: 3D9.257C5B207A

Fork Length (mm): 94

Recapture (mm): 120

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (7/22/06)

2 (11/2/06)

Fish ID: 3D9.257C5CEA81

Fork Length (mm): 190

A29 A30 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (8/2/07)

1 (6/22/07)

2 (7/16/07)

Fish ID: 3D9.1C2C465E26

Fork Length (mm): 184

Recapture (mm): 184

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/14/07)

3 (10/23/07)

2 (10/1/07)

4 (10/30/07)

Fish ID: 3D9.1C2C599DF2

Fork Length (mm): 196

A31 A32 

Figures A29 – A32. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

74
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/14/07)

2 (10/30/07)

Fish ID: 3D9.1C2C5757CB

Fork Length (mm): 111

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/14/07)

2 (12/5/07)

Fish ID: 3D9.1C2C576038

Fork Length (mm): 191

A33 A34 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/14/07)

2 (9/10/07)

Fish ID: 3D9.1C2C574D5A

Fork Length (mm): 195

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (9/13/07) 1 (8/14/07)

Fish ID: 3D9.1C2C599D47

Fork Length (mm): 273

A35 A36 

Figures A33 – A36. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

75
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

3 (8/16/07)

1 (6/20/07)

2 (8/14/07)

Fish ID: 3D9.1C2C4689DD

Fork Length (mm): 148

Recapture (mm): 166

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/15/07)

2 (10/8/07)

Fish ID: 3D9.1C2C575510

Fork Length (mm): 213

A37 A38 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (7/20/07)

1 (9/24/06)

Fish ID: 3D9.257C5A416B

Fork Length (mm): 185

Recapture (mm): 215

3 (8/15/07)

4 (9/12/07)

5 (9/14/07)

6 (10/1/07)

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (8/15/07)

2 (11/10/07)

Fish ID: 3D9.1C2C5998F8

Fork Length (mm): 146

A39 A40 

Figures A37 – A40. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

76
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/26/07)

2 (10/21/07)

Fish ID: 3D9.1C2C486750

Fork Length (mm): 185

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/26/07)

3 (8/3/07)

2 (8/1/07)

Fish ID: 3D9.1C2C514222

Fork Length (mm): 136

A41 A42 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/20/07)

2 (8/1/07)

Fish ID: 3D9.257C67E861

Fork Length (mm): 138

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/20/07)

2 (8/31/07)

Fish ID: 3D9.1C2C46DBCC

Fork Length (mm): 159

A43 A44 

Figures A41 – A44. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

77
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/20/07)

2 (11/9/07)

Fish ID: 3D9.1C2C5139D2

Fork Length (mm): 136

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/20/07)

2 (8/14/07)

Fish ID: 3D9.1C2C514651

Fork Length (mm): 142

A45 A46 

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

1 (6/21/07)

3 (8/22/07)

2 (8/18/07)

Fish ID: 3D9.1C2C48916D

Fork Length (mm): 148

2 (11/4/07)

Fish ID: 3D9.257C5CAC16

Fork Length (mm): 245

1 (6/21/07)

A47 A48 

Figures A45 – A48. Movement of PIT-tagged bull trout within the Jarbidge River subbasin in 2006 

and 2007. Each map represents a single bull trout and the number next to the symbol represents 

the order of events (1 = tagging, 2 = interrogation or recapture, 3 + = subsequent interrogation or 

recapture). See table 8 and figures 28 and 29 for installation dates and summaries of interrogation 

information. 

78
Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (7/17/07)

1 (8/20/06)

Fish ID: 3D9.257C5D2B4A

Fork Length (mm): 360

Recapture (mm): 400

Dave Cr.

West Fork Jarbidge

Jack Cr.

Pine Cr.

East Fork Jarbidge

Slide Cr.

Fall Cr.

Sawmill Cr.

Jarbidge

Murphy Hot Springs

Cougar Cr.

PIT tag interrogator

Fish barrier

0 234 1 km

Buck Cr.

2 (8/9/07)

1 (9/10/06)

Fish ID: 3D9.257C5AE09F

Fork Length (mm): 130

Recapture (mm): 180

A49 A50 

Figures A49 – A50. Movement of PIT-tagged bull trout that were within the Jarbidge River 

subbasin in 2006 and 2007. Each map represents a single bull trout and the number next to the 

symbol represents the order of events (1 = tagging, 2 = recapture). 

79
80

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Publishing support provided by the U.S. Geological Survey 

Publishing Network, Tacoma Publishing Service Center

For more information concerning the research in this report, contact the 

Director, Western Fisheries Research Center

U.S. Geological Survey, 6505 NE 65th Street

Seattle, Washington 98115

http://wfrc.usgs.gov/
Allen and others— Distribution and Movement of Bull Trout in the Upper Jarbidge River Watershed, Nevada—Open-File Report 2010-1033