Madison-Gallatin Fisheries Annual Monitoring Report

3

/ 3 - -

2002

By Patrick A. Byorth and Tim Weiss

Montana Fish, Wildlife and Parks
1400 S. 19* Street
Bozeman, MT 59718

April 2003

Abstract

The Madison and Gallatin watersheds provide ample fishing opportunities and an abundance of
high quality aquatic resources. Managing diese fisheries requires consistent monitoring and assessment of
long-term trends. This document summarizes survey and inventory data collected during 2002. Trend
information and current status of fisheries inhabiting major waters are provided for each survey conducted.
A niunber of challenges exist to wild trout fisheries in the area, such as whirling disease, increased angling
pressure, and drought. Nonetheless, most fisheries in the area are healthy and likely to persist with
continued protection of habitat and water quality and quantity.

Acknowledgements

Field surveys are generally intensive activities that require hard work under sometimes-difificult
conditions. The authors appreciate the assistance of the following individuals who participated in surveys:
Wally McClure, Scott Bamdt, and Darin Watschke (USFS) conducted spawning surveys on the West Fork
Hyalite Creek. Pat Clancey, Gary Senger, Reed Simonson (FWP), Scott Bamdt (USFS), Buddy Drake, and
Chris Weiss assisted in major rivers electrofishing. A number of FWP employees assisted in Hebgen
Reservoir gill netting, including Wayne Black, Deanna Meredith, Bob McFarland, Harry Whitney, Gary
Senger, Tim Schwartz, Jerry Walker, Shannon Knodl, and Reed Simonson. Dave Pac and Wendy Zimgibl
(FWP) and the staff of Ennis National Fish Hatchery clipped fins. Dave and Laurie Schmidt of Wade Lake
Resort assisted in surveys of Cliff Lake and provided moral support. Thanks to all of those who assisted
us that we were unable to list. We also appreciate the support of anglers and hunters who fund the
protection and enhancement of our natural treasures.

2

Introduction

The rivers, lakes, streams and reservoirs of the Madison and Gallatin watersheds support abundant
high quality aquatic resources. Of the 699, 747 angler-days exerted in Fish, Wildlife, and Parks (FWP)
administrative Region 3, approximately 47% occurred in these watersheds (MacFarland and Meredith
2002). Diverse fisheries in the Madison and Gallatin provide substantial recreational and economic value
to the state and local communities. World-renowned trout rivers, alpine lakes, three reservoirs, and
numerous urban ponds each provide a different angling experience and management challenge.

Montana Fish, Wildlife, and Parks’ Fisheries Division is funded through hunting and fishing
license sales and through the Federal Aid in Sport Fish Restoration Act (16 U.S.C 777-777k). Broad
objectives for the Fisheries Division are established in a Six-Year Operations Plan (FWP 2000a).

Objectives modified from the plan are:

1 . Survey and Inventory : Survey and monitor the characteristics, status, and trends of fish
populations, habitats, and angler use and harvest in selected streams and lakes,

2. Technical Guidance and Information : Review projects, public and private, that have the potential
to affect fisheries resources and provide technical advice to sustain and enhance fisheries
resoxirces,

3. Fish Population Management : Implement fish stocking programs in habitats that can’t sustain
fisheries naturally, to maintain fish populations and angler opportunities, and

4. A quatic Education : Enhance the awareness, understanding, and support of aquatic resources by
the general public to ensure that quality aquatic resources persist that encourage recruitment of
young anglers and advocates.

Monitoring is a critical component to managing quality fisheries and aquatic habitats. This report
summarizes survey and monitoring activities within the Madison - Gallatin District, project F-1 13 R2 and
F-1 13 R3 for calendar year 2002. Data reported herein are continuations of historic monitoring and may
have been recently reported by Byorth (2000a, 2000b) and Byorth and Weiss (2001, 2002), This report
provides only basic trend information as an index of the status of certain fisheries. Long-term monitoring
provides the context for interpreting annual data. Further analysis is necessary to draw conclusions beyond
basic trends.

Description of Study Areas

Gallatin River

The Gallatin River is the easternmost of three major Missouri River headwaters draining
approximately 1800 miles^ of southwestern Montana (Figure 1) (Shields et at. 1 999). Wild trout fishing is
the prominent attraction to the East and West Gallatin rivers, and their tributaries. These streams provided
an estimated 102, 836 angler-days in 2002, a decrease from 107, 315 angler days in 1997 and 121,146 in
1999 (McFarland and Meredith 1999, 2000, 2002).

3

LopaS«ctiim

P«cqpibt St<tte

Mi S«(£k!»

'\y

Figure 1 . Map of the Gallatin Drainage, showing population monitoring study sections.

The West Gallatin River flows north through the high-altitude, narrow Gallatin Canyon, which
divides the Madison and Gallatin mountain ranges. The canyon governs typically cool mid-summer water
temperatures and harsh winter conditions. Trout grow slowly in the cool water temperatures: an average
rainbow trout fOncorhvncus mvkiss) in the upper West Gallatin River will grow only to 12 inches after 4 to
5 years (MFWP Files). Severe winter conditions regulate trout abundance. In dry years, the lower West
Gallatin River becomes severely dewatered by irrigation diversions (Vincent 1978), The lower 35 river
miles of the West Gallatin River is more heavily influenced by irrigation diversions and channel instability.
Urban and suburban development has increased attempts to stabilize the river by channelization and
riprapping.

We monitor Fall trout populations in three survey sections in the upper West Gallatin River: the
Porcupine Section (2,3 miles: from Porcupine Creek to the West Fork of the West Gallatin River), Jack
Smith Section (2.2 miles: Jack Smith Bridge, Highway 191 North of Big Sky) and the Williams Bridge
Section (2.84 miles: Williams Bridge to 1 mile South of Gallatin Gateway) (Figure 1). The Jack Smith and
Porcupine Sections are sampled in even-numbered years (e,g. 2000, 2002) , while the Williams Bridge
Section is sampled in odd numbered years (e,g. 2001, 2003). Each of these sections has been electrofished
intermittently since the 1980’s. Detailed maps of each section are in Appendix A.

The headwaters of the East Gallatin River drain the Gallatin, Bangtail, and Bridger ranges,
joining near Bozeman (Figure 1). The 40 mile course of the East Gallatin River winds through developed
urban, suburban, and agricultural areas before its confluence with the West Gallatin River. In the past, fish
populations were heavily influenced by effluent from the Bozeman Municipal Sewage Treatment Plant.

The primary treatment plant was replaced by a secondary treatment facility in 1971, improving, water
quality and increasing wild trout abundance (Vincent 1978, Vincent 1979, Vincent and Rehwinkle 1981).

Two contiguous study sections have been sampled annually during fall to monitor trout population
trends in the East Gallatin River. The Upper Hoffinan section extends 0.88 miles from Springhill Road
Bridge to approximately 100 yards above the sewage outfall. The Lower Hoffinan Section begins at the
sewage outfall and extends 1,05 miles downstream.

The Thompson Section was reestablished in Spring of 2001, The section lies between Pen well
Bridge and the mouth of Trout Creek (1.6 miles), approximately 3 miles northwest of Belgrade, MT. In
this reach, the East Gallatin River increases in flow due to substantial groundwater accretions. Historically,
this reach was severely impacted by channelization and agricultural practices.

The last time fish populations were sampled in the Thompson Section was in 1984, We sampled this
section to monitor trout populations and increasing risks of whirling disease in the basin.

The East and West Gallatin rivers join approximately 12 river miles upstream of the headwaters of
the Missouri River, Combined influences of irrigation withdrawals, urban development, and sedimentation
appear to restrict trout populations in the mainstem Gallatin River. The Logan Section is electrofished

5

during spring to monitor trout populations in the mainstem. The section is 4.3 miles long extending from
Nixon Bridge to near the town of Logan, Montana (Figure 1).

Madison River

The Madison River forms in Yellowstone National Park, flowing into Montana near Hebgen
Reservoir (Figure 2). The Madison’s legendary trout fishery remains one of the most popular in the United
States (Sample 1998, Ross 1999.) The Madison River is the home of “wild trout management”, where
management emphasis shifted from stocking trout to population monitoring, harvest regulation, and habitat
protection (Vincent 1987, Vincent et al. 1990).

Madison River trout populations were monitored by electrofishing three study sections in 2002
(Figure 2). Detailed maps of each section are in Appendix A. The Pine Butte section lies approximately
12.0 miles below Quake Lake, extending from Pine Butte Creek to Lyons Bridge (3.0 miles). The
Madison River through this reach has fairly uniform gradient, with a network of side channels that
influence spawning and recruitment. The West Fork Madison River enters the Pine Butte Section
approximately 0.6 miles above Lyons Bridge. Fishing regulations on this reach have been catch-and-
release only for trout since 1978 and no fishing from boats has been allowed since 1974. Since 1995, the
fishing season has been open from the third Saturday in May through the end of February to protect
spawning rainbow trout. Population estimates have been conducted on the Pine Butte Section since 1977.

The Madison River changes character considerably in flie Varney Section, approximately 40 miles
downstream from Quake Lake. This section extends from Varney Bridge to Eight Mile Ford Fishing
Access Site, a length of 4.0 miles. Brown trout predominate in the complex and heterogeneous habitats
that a braided channel provides. Habitat in the Varney section is highly influenced by ice gorging (Vincent
1990). Annual fall population surveys have been conducted in the Varney Section since 1967. Fishing
regulations allow harvest of 5 brown trout tSalmo trutta) . only one over 18 inches long, catch-and-release
only for rainbow trout, in effect since 1992.

The Madison River changes significantly below Ennis Dam. After flowing 8 river miles through
Beartrap Canyon, the Madison flows through a low gradient, broad and shallow channel with extensive
weed beds and fine sediments. Mid-summer water temperatures climb to near lethal levels in this reach,
causing fish kills in dry, and hot years (Vincent et al. 1981). We monitor trout populations in the 4.0-mile
Norris section, extending from the mouth of Warm Springs Creek to the mouth of Cherry Creek. This
reach is open to fishing year-round with a combined trout limit of 5 fish, only 1 over 18 inches long.
Population estimates have been conducted in spring in the Norris Section annually since 1970.

6

Figure 2. Map of Madison River drainage with population survey study sections.

7

Hebgen Lake

Hebgen Lake is a storage impoundment on the Madison River, formed by Hebgen Dam in 1915.
The dam is owned and operated by PPL Montana under FERC License 21 88 to regulate flows to the
hydroelectric plant at Madison Dam near Ennis. At foil pool elevation of 6534 feet above mean sea level
(amsl), the reservoir’s surface area is 12668 acres. The primary fishery management goal at Hebgen Lake
is to establish a self-sustaining rainbow trout population. The reservoir fishery is supported by wild, self-
sustaining brown trout and rainbow trout, but is supplemented with annual plants of 100,000 eagle lake
rainbow trout fiy, a wild strain. Mountain whitefish fProsopium williamsoni) , native to the Madison
Ehainage, also complement the fishery. Utah chubs tOila atraria) , introduced circa 1935, occupy a large
proportion of fish biomass in Hebgen Lake (Leik 1978).

Clifi~ and Wade Lakes

Cliff Lake is a natural lake at an elevation of 6313 amsl covering approximately 620 surface acres.
Naturally reproducing rainbow trout have historically sustained this fishery, although it was occasionally
supplemented with hatchery plants. Cliff Lake’s fishery has struggled in the last 40 years. A 1961
graduate project found the lake’s rainbow trout population to be heavily parasitized (Fox 1961). This,
accompanied by disease and overpopulation, was suspected as a reason for the fishery’s decline.

Wade Lake is a 240 acre natural lake, the last in the same chain as Cliff Lake. It lies at an
elevation of 6217 amsl. Wade Lake is sampled periodically to ensme trout populations are stable, but no
sampling was conducted in Wade Lake in 2002
Hyalite Reservoir

Hyalite Reservoir is an irrigation storage impoundment on Hyalite (Middle) Creek, filled in 1951
with the completion of the Hyalite (Middle) Creek Dam. In 1993, dam reconstruction raised foil pool
elevation 8.2 vertical feet to 6715 amsl with surface area of approximately 260 acres. The increase in pool
elevation inundated critical spawning habitats, apparently impacting Yellowstone cutthroat trout
fOncorhvncus clarki bouveri) and Arctic grayling (Thvmallus arcticusi populations (Byorth and Weiss
2001). Smnmer and fall irrigation in the Gallatin Valley and municipal diversions significantly draw pool
elevations dovra each year. While Hyalite Reservoir sustains wild, self-sustaining populations of
Yellowstone cutthroat trout (YCT), Arctic grayling, and brook trout fSalvelinus fontinalis) , approximately
30,000 YCT fiy are planted annually.

Recent management efforts focused on maintaining satisfactory angler catch rates of YCT by
supplementing the naturally reproducing population with McBride strain hatchery YCT. In addition, we are
monitoring success of mitigation at protecting the grayling population in conjunction with the Gallatin
National Forest. In 2002, a series of log jams were created by felling conifers into the stream channel to
enhance scour and deposition of spawning gravels, to provide overhead cover for spawners, and to enhance
rearing habitat.

8

Miscdlaneous Surveys

In June 2002, we surveyed Deer and Moon lakes in the Deer Creek drainage (T6SR4E Sec. 7),
approximately 28 miles southeast of Bozeman, MT. Deer Lake lies at an elevation of 9 120 feet amsl. A
wild, self-sustaining population of Arctic grayling inhabits Deer Lake, Moon Lake is less than a mile south
of Deer Lake at 8950 ft amsl. Moon Lake supports a self-sustaining population of rainbow-cutthroat trout
hybrids. We characterized the spawning population to document natural reproduction by electrofishmg
spavming streams at each lake.

Methods

Electrofishing is used to conduct Mark-Recapture experiments to estimate trout populations. A
drift boat-mounted, mobile anode system is used to capture trout on large rivers such as the Madison,
Gallatin, and East Gallatin rivers. The drift boat system is equipped with 4,500 Watt generator and Coffelt
Mark XXII-M rectifying Unit. During electrofishing runs trout are netted, held in a live well, anesthetized
in an MS-222 bath, measured to 0. 1 inches in total length, weighed to 0.0 1 lbs, marked with a fin clip, and
released after recovering. Multiple marking runs are followed by recapture runs after 10 to 14 days. The
number of electrofishing passes is determined by the sample sizes required to construct statistically valid
population estimates (generally more than 10% of the population). The ratio of marked to unmarked fish in
the recovery sample is used to estimate abundance according to FWP’s computerized Mark-Recapture Log-
likelihood model. On smaller streams, we use a backpack-mounted electroshocker to capture trout and
generally use similar fish handling methods and calculate depletion estimates. Scale samples are collected
for age determination and to determine age class abundance. Detailed maps of study sections are in
Appendix A.

We use gill nets to sample Hyalite Reservoir, Hebgen Lake, and Cliff Lake. We set experimental
gill nets 125 feet long by 6 feet deep with a bar mesh ranging from 1 to 3 inches. At Hebgen Reservoir,
annual sampling occurs during the last week of May or the first week of June. A combination of 24 to 27
bottom and surface nets were set over a three-night period. Nets are set at consistent locations each year,
although low reservoir levels dictated the omission of certain sets in some years (Appendix A). Gill nets
were set at Cliff Lakes in October 2002. In addition to the traditional four surface nets, we changed the
location of one sinking net and added another in Cliff Lake. (Appendix A). We set 3 fioating and 1 sinking
gill nets in Hyalite Reservoir in October 2002 (Appendix A).

On each take or reservoir, gill nets are set during late afternoon and retrieved the following
morning. Fish found alive are processed and released. All fish caught in nets are identified to species,
measured to nearest 0.1 inch in total length, weighed to nearest 0.01 lb., and examined for marks, hook
scars, and sexual condition. Scale samples are taken from trout for age analysis. On Hebgen Reservoir,
rainbow trout were examined for external hatchery characteristics and we extracted vertebrae from
deceased specimens to examine for tetracycline marks. A microscope and a blacklight were used to
examine vertebrae for tetracycline marks.

9

Hyalite Reservoir salmonids are monitored annually by spawning surveys. Yellowstone cutthroat
trout and Arctic grayling both spawn in the West and East Forks of Hyalite Creek. Spawner counts are
conducted May ™ July annually, from reservoir pool elevation to Window Rock Bridge on the West Fork.
Surveyors walk upstream, counting adult fish of both species, generally 2 days per week for the duration of
spawning (generally mid-May to mid- July).

Results

West Gallatin River

Trout populations are stable in reaches of the West Gallatin where monitoring is conducted. In the
Gallatin Canyon (Porcupine and Jack Smith sections) rainbow trout predominate and brown trout are
present m low numbers. Brown trout abundance in the Porcupine Section was estimated to be 66 per mile
in 1998, 118 per mile in 2000, and HO per mile in 2002. Apparently, brown trout recruitment is very
limited in the canyon. Rainbow trout populations in the canyon were the highest on record for fish 8.0
inches and longer. This is a continuation of a long-term trend in both Porcupine and Jack Smith sections
since an apparent decline in the mid 1990’s in both sections.

In the Porcupine Section, numbers of rainbow trout 8 inches and longer increased above levels
documented in 1998 and 2000 (Table 1). However, the oldest rainbow trout in the largest size class (>13.0
inches) declined from previously recorded highs to near long-term average (Table 1). However, age 4 and
54- rainbow trout remain at healthy levels relative to 1996 levels (Table 2). Age 2 and 3 rainbow trout are
stable at strong levels and are likely to maintain numbers of larger trout in the next few years. Ample
recruitment is apparent in Age 1 and 2 rainbow trout, likely due to low intensity spring runoff in the last
few years. Table 3 demonstrates the slow grovrth rates of rainbow trout in the Gallatin Canyon, reaching
only an average of 9.0 inches as age 3, the likely age of sexual maturity.

Table 1 . Rainbow trout population summary for trout longer than 8.0 inches (generally Age 3 and older) in
the Porcupine Section of the West Gallatin River, Fall 1984 - 2002. Values are number per river mile by
length category.

Year

Number > 8 inches

Number > 10 inches

Number > 13 inches

1984

915

329

29

1987

1250

412

25

1995

819

386

100

1996

558

333

87

1998

1355

702

162

2000

1221

629

143

2002

1514

770

104

10

Table 2. Rainbow trout population estimates by age class in the Porcupine section of the West Gallatin
River, Fall 1996, 1998, 2000. Vaiies for 2002 are based on previously documented length-at-age estimates
and should be considered preliminary. Values are number per river mile. Standard deviations (SD) are
provided for total population estimates for finalized estimates.

Estimated Number By Age Class (number per mile)

Year

Age 1

Age 2

Age 3

Age 4

Age 5+

Total (SD)

1996

570

358

269

111

198

1510(47)

1998

384

383

418

406

566

2157(245)

2000

278

447

515

303

357

1900 (210)

2002

408

1031

744

469

301

2953

Table 3. Mean length-at-age of rainbow trout in the Porcupine Section of the West Gallatin River, Fall
1996, 1998, and 2000.

Mean Length by Age Class (inches)

Year

Age 1

Age 2

Age 3

Age 4

Age 5

1996

4.7

6.9

8.7

10.5

12.8

1998

5.4

7.3

8.9

10.1

11.5

2000

5.2

7.0

9.2

10.5

12.7

3 year
Mean

5.1

7.1

8.9

10.4

12.3

Rainbow trout populations in the Jack Smith section are similar to the Porcupine section,
displaying a peak in density in the late 1980’s with a decline in the mid 1990"s and a more recent increase.
While rainbow trout abundance in the Jack Smith Bridge section increased more recently than in the
Porcupine Section, rainbow trout abundances remain at high levels (Table 4). Population estimates in
2000 and 2002 are substantial. Byorth and Weiss (2002) questioned whether high abundances in 2000
were an artifact of conditions during sampling. However, the 2002 estimates confirm the validity of the
2000 estimates. While estimated abundances decreased across size classes relative to 2000, the rainbow
trout population in the Jack Smith section remains strong. Analysis of age class strength indicates strong
survival of the 1997 (Age 3 in 2000, Age 5 in 2002) and the 1998 year class (age 2 in 2000, age 4 in 2002)
(Table 5).

11

Table 4. Estimated population of rainbow trout in the Jack Smith section of the Gallatin River obtained
during the late summer or early fall of 1981-1984, 1989, 1995-1996, 1998, 2000, and 2002. Estimates are
presented as nmnber per river mile.

Year

Number > 8 inches

Number > 10 inches

Number > 13 inches

1981

2819

1169

167

1982

2308

910

99

1983

2596

1217

108

1984

2490

1149

123

1989

3449

1413

131

1995

1460

896

181

1996

1505

936

237

1998

1464

749

167

2000

4946

2381

402

2002

3453

1945

286

Table 5. Estimated rainbow trout abundance in the Jack Smith Section of the West Gallatin River by age
class, fall 1981 - 2000. Abundance estimates are in number per river mile. The estimate for 2002 is based
on previously documented length-at-age ratios and should be considered preliminary. The others are based
on actual scale samples and standard deviations (SD) are provided for total population estimates.

Year

Age 2

Age 3

Age 4

Age 5+

Total (SD)

1981

2034

973

353

182

3542 (574)

1982

1951

1017

279

80

3327(211)

1983

1784

1300

431

123

3640 (217)

1984

936

1324

614

387

3262 (198)

1989

2231

1453

763

270

4718(321)

1995

437

380

350

855

2022 (229)

1996

1086

507

327

827

3257 (398)

1998

676

700

473

211

2882 (345)

2000

2606

2178

630

687

7450 (804)

2002

1709

1508

1086

859

5162

East Gallatin River

Trout populations in the East Gallatin River have been relatively stable. In the Upper Hoffman
Section, numbers of rainbow trout increased slightly in all size classes from levels documented in 2001
(Table 6). Brown trout abundance was very similar to levels in 2001 . In the Lower Hoffrnan Section, both
rainbow and brown trout abundance decreased in each size class. The Upper and Lower Hoffman Sections

12

are contiguous, so it is odd that trout abundances documented in 2002 were inconsistent between sections.
Generally, both sections follow the same trend. Without more complete analysis of age class strength, it is
difficult to assess the reasons for these mixed results. Length-at-age information is summarized in Table 7.

The presence of Mvxobolus cerebralis . the parasite that causes whirling disease in salmonids, has
been documented in the East Gallatin River and the intensity of infection in rainbow trout is increasing (D.
Vincent, Pars. Comm.). Whirling disease is likely to impact rainbow trout populations in the near fiiture
and infection rates may be higher below the outfall of the sewage treatment plant. Ongoing investigations
will clarify the impacts of whirling disease in the East Gallatin River.

Table 6. Rainbow and brown trout population summary (age 1+) for the upper and lower Hoffman sections
of the East Gallatin River, 1994 “ 2002. Population estimates per mile are listed by length group.

I Upper Hof&nan Section

(1.2 miles)

Year

(Fall)

rainbow trout per mile

1 Brown trout per mile

>6.0

inches

> 10.0
inches

> 13.0
inches

>6.0

inches

>10.0

inches

> 13.0
inches

1994

2550

600

847

645

271

1995

2157

ggillllllllll^

1103

669

453

1996

2397

ggjjjjll^

384

310

229

1997

1701

697

290

155

99

1998

3108

668

152

522

266

137

1999

4877

1712

663

427

208

2000

3408

1083

188

1053

724

358

2001

1649

648

80

748

458

262

2002

2014

830

143

693

522

269

Lower Hoff

man Section

(0.88 miles)

Year

(Fall)

>6.0

inches

>10.0

inches

> 13.0
inches

>6.0

inches

^10.0

inches

2:13.0

inches

1994

2089

219

556

397

226

1995

3498

320

501

363

225

1996

2557

277

646

550

464

1997

1915

982

359

316

1998

3376

1237

647

355

1999

4801

2288

653

757

539

198

2000

4633

3164

647

765

408

205

2001

739

526

319

138

2002

1795

1309

584

303

260

131

13

Table 7. Length-at-age (inches) estimates for rainbow and brown trout in the Hoffman sections of the East
Gallatin River based on scale samples 1985 - 1987.

Species

Age 1

Age 2

Age 3

Age 4

Age 5

Age 6

Rainbow

Trout

IH

9.3

10.7

11.9

13.2

13.7

Brown

Trout

■n

12.6

14.0

15.0

16.0

The Thompson section of the East Gallatin River was electrofished m spring of 2001 and 2002 to
characterize trout populations and assess the potential effects of whirling disease on rainbow trout.

Rainbow trout predominate in the Thompson Section, although both rainbow and brown trout are
significantly less abundant than in the Hof&nan sections approximately 7 ah miles upstream. Both rainbow
and brown trout abundances reflect a lack of juvenile trout, comprising less than 15% of the populations
(Table 8). Recruitment limitation of rainbow trout could be explained by the presence of whhling disease.
However, brown trout are resistant to whhling disease, so the factor limiting theh reproductive success may
be water quality related. Rainbow trout recruitment may be limited by the same factor. In either case, both
trout populations decreased between 2001 and 2002, almost certainly due to drought related conditions.

Table 8. Rainbow and brovm trout population estimates (number per mile) in the Thompson Section (1.6
miles below Penwell Bridge) of the East Gallatin River, Montana, Spring 2001 and 2002.

Brown Trout

Rainbow Trout

Year

>5.0

inches

>10.0

inches

>13.0

inches

>5.0

inches

>10.0

inches

>13.0

inches

2001

449

437

331

928

879

2002

450

390

243

758

654

402

Gallatin River

The Gallatin River below the confluence of its forks suffers a variety of cumulative impacts
including sedimentation, warm water temperatures, dewatering, and presence of M. cerebralis, the
causative agent of whhling disease. Trout population estimates are relatively stable at low levels relative to
both forks of the Gallatin River. Estimated rainbow and brown trout populations decreased from 2001 ,
which may be attributable to persistent drought conditions (Table 9). Larger fish dominate both rainbow

14

and brown trout populations. The absence of juvenile rainbow or brown trout (less than 10 inches long)
indicates recruitment limitation. This may be symptomatic of whirling disease, although brown trout are
not subject to the disease.

Table 9. Rainbow and brown trout population estimates (number per mile) in the Logan Section (4.3 miles
below Nixon Bridge) of the Gallatin River, Montana, Spring 1999-2002.

Brown Trout

Rainbow Trout

Year

>6.0

inches

>10.0

inches

>13.0

inches

>6.0

inches

>10.0

inches

>13.0

inches

1999

473

390

208

353

270

107

2000

350

307

128

321

281

103

2001

304

274

184

487

454

344

2002

302

267

143

392

370

240

Madison River

Rainbow and brown trout populations in the Madison River above Ennis Reservoir have been
affected by a variety of influences over the years (Byorth 2000a). Since 1991, whirling disease has been
the primary factor limiting rainbow trout populations in the upper Madison (Vincent 1996). The rainbow
trout population in the Pine Butte section declined since it peaked in 1999 and 2000. While the 1998 year
class of rainbow trout survived well into larger size classes, the 1999 and 2000 year classes were
substantial, but experienced limited survival to maturity.

Drought-related conditions are the most likely factors affecting survival and recruitment of
juvenile trout. Lower stream flows have been implicated in increasing susceptibility of emergent rainbow
trout fiy to whirling disease in the upper Madison River (Dick Vincent, personal communication). Lower
stream flows during late fall and winter apparently dimmish winter habitat quality for juvenile trout and
may amplify effects of whirling disease on juvenile rainbow trout. Flow related limiting factors are further
evident in brown trout population estimates (Table 10). Strong brown trout year classes from 1995 to 1998
occurred during years of ample moisture, when overwinter survival of yearling trout increased as fall
drafting of Hebgen Reservoir increased late fall and winter flows (Table 1 1). Lower fall and winter flows
since 2001 appear to have impacted brown and rainbow trout populations, affecting recruitment of

15

juveniles and survival of adult brown trout. However, brown trout abundance is still within long-term
ranges.

Table 10. Rainbow and brown trout population estimates in (number per mile) the Pine Butte Section (3.0
Miles above Lyons Bridge) of the Madison River, Montana, Fall 1994-2002. Standard deviations (SD) are
listed for finalized estimates.

Rainbow Trout

Year Age 1 Age 2 and older Total Age 1 and older

Per Mile

Per Mile Per Mile (SD)

1994

94

236

330 (20.5)

1995

510

175

685 (65.8)

1996

735

447

1182 (88.9)

1997

454

267

1998

847

305

1999

2729

656

2000*

2100

1659

3759

2001*

1794

702

2496

2002*

661

420

1081

Brown Trout

Year Age 1 Age 2 and older Total Age 1 and older

Per Mile Per Mile Per Mile (SD)

1994

282

919

1201 (157.7)

1995

620

509

1129 (70.7)

1996

1158

446

1604 (84.2)

1997

831

929

1760 (154)

1998

1018

794

1812 (103.4)

1999

1419

1373

2792 (497.7)

2000 *

962

1171

2133

2001*

728

1024

1752

2002*

585

534

1119

*2001 Preliminary, based on historic age data, subject to change with actual scale data.

Table 11. Mean Monthly Stream flows for the Madison River at the Kirby Gage, 1995 -2002.
Values (in bold) for October 2001 through December 2002 are estimated from USGS provisional data
(USGS Web Site: http://waterdata.usgs.gov/mt/nwis/current)

Year

Jani

Feb

Marj

Apr)

May!

June;

July)

Aug.

Sept:

Octj

Novi

Decj

1995

l,527j

2,581!

1,253]

l,295j

1,566!

1,102;

1996

971 1

931j

iiM

[ggi

2,7^1

3,552j

1,544)

1,259)

1,567)

2,136:

2,026

1997

l,385j

1,398

1,386!

2,864;

3,862!

l,757i

1,671)

1,529!

Mali

MHIItEi

1998 j

l,338j

1,313

l,224j

_l,558j

l,26lj

1,184:

1,178!

1,247:

1,379)

1999

l,449j

1,521

1,611]

1,491 i

1,895;

2,955:

1,561|

1,262:

1,252)

2000

1,243(

1,242|

1,290!

1,298!

1,734;

l,l6l|

l,063j

1,149

1,162)

1,136

U4^

2001

1,140)

882

756

lEPI

9561

96^

2002

1^^

825

825

KSSi

980

Mean of i
monthly
streamflows;

1

l,051i

1,059

1,028|

1

1,895

1,325

1,150

r ;

1,201

:

l,674i

i

1

1,6761

1,272

16

In the Varney section, brown trout are the predominant species contributing to the trout fishery.
After fall populations of age 1 and older brown trout peaked in 1998, they remained strong through 2000 at
above average levels (Table 12), In 2001, abundance of brown trout decreased across age groups, in spite
of apparently good recruitment of the 1999 year class. Stronger juvenile brown trout recruitment boosted
the population in 2002, although continued flow limitations may have impacted over- winter survival into
2003.

Rainbow trout significantly decreased in abundance in the Varney section in the mid-1990’$,
apparently as a result of whirling disease (Byorth 2000a). In the Varney section, estimated fall rainbow
trout abundance increased with good recruitment from the 1998 and 1999 year classes, similar to the Pine
Butte Section. A downward trend in rainbow trout abundance began in 2001 with diminished recruitment
from the 2000 and 2001 year classes. However, the 2000 year class recruited well to the adult population,
and maintained the rainbow trout population in the Varney Section near average numbers in 2002,

Table 12. Rainbow and brown trout population estimates (number per mile) in the Varney Section (Varney
Bridge to Eight-mile Ford, 4.0 miles) of the Madison River, Montana, Fail 1994-2002. Standard deviations
(SD) are listed for finalized estimates.

Rainbow Trout

Year Age 1 Age 2 and older Total Age 1 and older

Per Mile Per Mile Per Mile (SD)

1994

33

166

199 (27.6)

1995

351

132

483 (70.4)

1996

145

304

449 (54.9)

1997

106

113

282 (28.3)

1998

192

139

331 (36.2)

1999

740

236

976 (190.4)

2000*

1366

409

1775

714

281

995

634

535

1169

Brown Trout

Year Age 1 Age 2 and older Total Age 1 and older

Per Mile Per Mile Per Mile (SD)

1994

1278

631

1909 (75.1)

1995

770

704

1474 (76.3)

1996

1558

515

2073 (84.4)

1997

1122

949

2071 (123.5)

1998

1061

3241 (132.8)

1999

1674

1244

1706

1076

EEISOBBI^^

1133

850

1983

2002*

1237

1103

2340

*2000-02 Preliminary, based on historic age data, subject to change with actual scale data.

Trout populations of the Madison River below Ennis Reservoir are subject to different
environmental factors than above Madison Dam. Ennis Reservoir acts as a thermal sink, increasing mid-
summer water temperatures (Vincent et al. 1981). While warm temperatures apparently suppress whirling

17

disease, temperatures can approach lethal levels and affect trout survival By 2001, rainbow and brown
trout abundance in the Norris Section had nearly recovered from low levels in the mid-1990’s (Table 13).
However, persistent drought conditions appear to have affected survival of Age 3 and older rainbow and
brown trout in 2002. Numbers of Age 2 brown trout in Spring 2002 are low, reflecting poor recruitment
in 2000 or sampling error.

Table 13, Rainbow and brown trout population estimates (number per mile) in the Norris Section (Warm
Springs Creek to Cherry Creek, 4.0 miles) of the Madison River, Montana, Spring 1994-2002. Standard
deviations (SD) are listed for finalized estimates.

Rainbow Trout

Year Age 2 Age 3 and older Total Age 2 and older

Per Mile Per Mile Per Mile

1995

273

531

804 (55.7)

1996

184

535

719 (62.5)

1997

552

220

772 (38.7)

1998

555

736

1291 (104.5)

1999

820

772

1592 (266.9)

2000

330

937

1267 (76.6)

2001*

643

1422

2065

2002*

868

758

1626

Brown Trout

Year Age 2 Age 3 and older Total Age 2 and older

Per Mile Per Mile Per Mile (SD)

1995

435

706

1141 (254.2)

1996

696

510

1206 (64.0)

1997

294

613

882 (63.0)

1998

601

507

1108 (66.1)

1999

980

1017

1997 (356.0)

2000

968

686

1654 (93.1)

2001 *

1085

1154

2239

2002*

626

989

1615

*2001-2002 Preliminary, based on historic age data, subject to change with actual

scale data.

Hebgen Reservoir

Annual spring gill net series are used to gather trend information as an index of relative abundance
of game and non-game species. While wild reproduction predominates for all species, approximately
100,000 Eagle Lake strain rainbow trout are stocked annually. In 2002, catch of rainbow trout in floating
nets (the best index of rainbow trout abundance) rebounded to above average levels (Table 14). Long term
average catch per net between 1973 and 2001 was 5.4 (SD 3.43) rainbow trout per net in spring floating
nets. Prior to 1986, the onset of stocking wild strains of rainbow trout, net catches averaged 2.42 (SD 1 .02)
rainbow per floating net. Since 1 986, spring catch rates of rainbow trout have averaged 6.76 (SD 3.28)
(Byorth and Weiss 2002). While decreased natural reproduction due to drought conditions or poor
planting success could explain lower catches in 2001, the low catch may have been due to sampling error.

We are still assessing the contribution of stocked rainbow trout to the Hebgen Reservoir fishery
and rainbow trout population. We are using a combination of observation of dorsal fin erosion,

18

tetracycline (tet) marks, and adipose fin clips to assess whether rainbow trout captured in gill nets are fi-om
hatchery or wild origin. Byorth and Weiss (2002) summarized inconsistencies in results of different point-
of-origin methods, concluding that hatchery comprised less than 25% of the rainbow trout population. In
2002, 17 of 51 rainbow trout captured in gill nets expressed a tet-mark. These rainbow trout ranged in
length from 11.1 inches to 15.8 inches, probably 2 and 3 year old trout. Of rainbow trout positive for a tet-
mark, 70% also exhibited dorsal fin erosion. In combination, fin erosion and tet-marks indicate the highest
proportion of hatchery rainbow trout in recent years (Table 15). We will continue to research hatchery
contribution to the rainbow trout population.

Catches of brown trout in gill nets in Spring 2002 decreased slightly from 2001. We caught 7,1
brown trout per sinking nets (the best index for brown trout abundance) which is below the long term
average of 10.94 (SD 3.44) since 1971 (Table 14). However, the gill net catch is consistent with catches
since 1995. Mountain whitefish catch rates have been relatively stable since 1994, although the catch per
sinking net fell in 2002 to the lowest levels in the period (Table 14). Utah chub catches have fluctuated
widely since 1994, apparently rebounding significantly in sinkmg nets, but decreasing from high levels
recorded in 1999 in floating nets.

Table 14. Summary of rainbow trout (RB), brown trout (LL), mountain whitefish (MWF), and Utah chub
(UC) catch-per-net in Spring gill net series on Hebgen Reservoir, 1995 to 2002.

Floating Nets

YEAR

NO. OF NETS

RB/NET

LL/NET

MWF/NET

UC/NET

1995

12

15.3

8,4

1.1

18.9

1996

14

5.9

4.3

0.7

54.6

1997

14

5.6

3.9

0.1

89.2

1998

14

9.4

2.6

1.1

41.1

1999

13

7.2

13.3

1.5

143.2

2000

14

6.0

3.7

0.2

96.0

2001

14

2.5

2.4

0.29

62.5

2002

14

7.0

3.2

0.9

53.3

Sinking Nets

YEAR

NO. OF NETS

RB/NET

LL/NET

MWF/NET

UC/NET

1995

12

0.8

7.1

18.5

13.4

1996

13

0.9

7.5

16.8

55.5

1997

11

0.8

8.5

16.3

24.5

1998

10

1.1

6.5

12.0

60.2

1999

11

0.8

11.7

19.4

26.6

2000

11

0.7

9.5

11.7

33.3

2001

11

0.5

11.1

18.1

69.2

2002

11

0.6

7.1

11,4

115.5

19

Table 15. Summary of contribution of wild and hatchery-reared rainbow trout to gill net catches in Hebgen
Reservoir, 1996-2001. Asterisks indicate incomplete data.

Year

% Catch Rainbow Trout
With Dorsal Fin Erosion

% of Sample Tet-Mark
Positive

1996

5.2 *

2.9

1997

13.8

2.7

1998

22.4

no data

1999

3.9*

2.9

2000

16.0

6.3

2001

22.5

0.0

2002

17.0

33.0

Cliff and Wade Lakes

Over the years, monitoring of fish populations in Cliff and Wade lakes has been limited to gill
netting or night electrofishing. In 2002, we did not sample Wade Lake and only gill netted at Cliff Lake.
Gill netting catches have varied considerably on Cliff Lake, reaching a low point in 1994 (Table 16). Since
then, rainbow trout catches have been relatively consistent with strong catches in 2000 and 2002. Mean
length of rainbow trout caught in gill nets is low, dominated by juvenile fish. The low mean size may be
due to strong juvenile populations, but a lack of larger rainbows could also reflect poor growth rates.. The
impact of parasite loads has not been adequately analyzed, but is likely the prime factor limiting growth
and survival.

Table 16. Summary of catch rates and average length of rainbow trout caught in gill nets in Cliff Lake,
1991-2002.

YEAR

Number

Number per net

Mean length

1991

46

7.7

12.4

1993

21

4.2

15.5

1994

9

1.8

12.3

1998

31

6.2

8.9

1999

26

5.2

10.9

49

9.8

9.4

2001

25

6.3

10.2

2002*

59

8.4

10.3

* 7 nets

20

Hyalite Reservoir

Spawner counts in the West Fork Hyalite Creek indicate Yellowstone cutthroat trout and Arctic
grayling may be recovering from the loss of spawning habitat due to raising reservoir levels (Byorth and
Weiss 2001). In 200 1 , a total of 2643 YCT were observed in the West Fork, a record high (Table 17).
Spawner counts were lower in 2002, but numbers of mature spawning YCT appear to be strong. Since
1 998, the numbers of adult Arctic grayling observed has stabilized near 20 per survey (Table 18). In 2002,
the observed number of spawning Arctic grayling decreased but is stable.

A fall gill netting series was conducted on Hyalite Reservoir, the first since 1998. In 2002, a total
of 80 YCT, 5 brook trout, and 1 grayling were captured in 4 nets. In contrast, 60 YCT, and 10 brook trout
were captured in 1998. Mean length of YCT increased from 11.4 inches in 1998 to 13.0 inches in 2002.
Netting results appear to corroborate spawner counts in indicating a relatively stable YCT population.

Table 17. Numbers of Yellowstone cutthroat trout (YCT) observed during spawner counts in the West
Fork Hyalite Creek, 1995-2002, * indicates years of incomplete surveys. Updated from Byorth and Weiss
2002.

Year

Number of Surveys

Number YCT
Observed

Number YCT
Per Survey

Peak Spawning Date

1995

6

259

43.2*

Jxme 12*

1996

4

13

4.3*

*

1997

8

364

45.5

June 23

1998

16

1891

118

May 28

1999

11

1704

155

June 11

2000

9

1640

182

June 2

2001

8

2643

330.4

June 6

2002

7

1980

282.2

June 7

21

Table 20. Numbers of Arctic grayling observed during spawner counts in the West Fork Hyalite Creek,
1986, 1989 - 2002, * indicates years of incomplete surveys. Updated from Byorth and Weiss 2002.

Year

Number of Surveys

Number Grayling
Observed

Number
Grayling
Per Survey

Peak Spawning Date

1986

1

152

152

June 16

1989

*

85

*

*

3

180

60

June 26

1

50

50

June 26

1992

2

154

77

June 10

1993

16

555

34

June 21

1994

20

945

47

June 6

1995

7

45

6.4*

June 29*

1996

4

0

0*

*

1997

8

5

0.6

June 23

1998

16

453

28.5

June 22

1999

11

203

18.5

June 24

9

130

14.4

June 13 “ 19

2001

8

175

22

June 19

2002

7

108

15.4

July 1

Miscellaneous Surveys

At Moon Lake, we electrofished approximately 100 yards of the inlet stream immediately above
the lake. We captured 1 8 rainbow-cutthroat hybrid trout ranging in length from 3.3 to 14.0 inches, with an
average of 1 1 .6 inches. Ten of the 1 8 were over 12 inches long. Spawning was underway, with 4 spent
females of the 9 mature females captured. The remainder was ripe. We also observed a few yearlings,
which appeared to be a couple inches long. The Gallatin-Madison moimtain lakes database indicated that
Yellowstone cutthroat trout were planted in 1995. A previous USFS report lists wild rainbow. Obviously,
the population is wild and self-sustaining, with good age distribution. Scales were collected for aging.

Deer Lake historically supported a wild Arctic grayling population. Deleray (1992) estimated the
spawning population to be 803 ± 104 in 1989 and 1 109 ± 124 in 1990. Scott Bamdt, USFS, and Cal Kaya,
MSU, conducted a marking run on 6/25/02 using a battery backpack unit. We followed up with a recapture

22

run on July 2. Both crews electrofished only the staging areas outlined by Deleray (1992) and did not enter
the spawning area. Our combined population estimate for mature fish:

M = 75 ( over 8.0 inches), C - 63 R - 5
Therefore, = [(75 + 1 >(634^1 )/(5+l)] - 1 - 809 ± 265

Size range of mature fish 7/2/02 was 10.7 - 14.7 inches with an average of 13.2 inches. On 6/25
length range was 8.6 14.5 inches. Bamdt and Kaya captured 51 irnmature grayling ranging from 2.6 to
8.05 inches. Sex ratio was 28 f:35 m on 7/2/02, and 38f:37m on 6/25/02. We captured spent females and
found eggs in the spawning stream indicating that peak spawning was underway. We observed spawning
behavior, paired fish, and aggression and observed 6-8 inch grayling and 2-3 inch grayling in stream. All
size classes were apparent and this population is stable.

Conclusion

In the Madison and Gallatin drainages whirling disease, flow regimes, drought, winter conditions,
predation (human and otherwise), and habitat condition each play a role in regulating trout abundance.

Most recently, persistent drought has effected populations in most of the area. However, milder winters
and low runoff appears somewhat beneficial to trout in the Gallatin Canyon. The interplay of whirling
disease and low winter flows appears to be impacting trout in the upper Madison drainage, especially in the
Pine Butte Section. While both rainbow and brown trout abundance decreased in the Pine Butte section,
trout abundance was stable in the Varney section. In the Norris section, below Ennis Lake, the older age
classes of brown trout, and to some extent rainbow trout, appear to be impacted by drought conditions.
Trout populations in the East Gallatin River also reflect drought impacts with decreasing abundance
especially at older ages. In both Thompson and Hoffinan sections, declining recruitment may be due to
increasing intensity of whirling disease.

Catch-per-efFort trends in Hebgen Lake increased to respectable levels after the temporary low in
2001 . In Hyalite Reservoir gill net catches and spawner counts suggest a stable fishery. While gill net
catches of rainbow trout on Cliff Lake were respectable, growth still appears to be hampered by parasite
loads. Moon Lake supports an apparently stable population of wild rainbow-cutthroat hybrids. The Arctic
grayling population in Deer Lake is self-sustaining and is similar in abundance to previous surveys.

This document reports monitoring activities in the Madison and Gallatin drainages during 2002.
Summary data are provided to illustrate trends in fish populations or to address specific management
concerns. Conclusions beyond the scope of basic trends are speculative and they would require more in-
depth analysis.

23

Literature Cited

Byorth, P. A. 2000a. Madison River trout population surveys; July 1994 ~ June 1999, project 3302.
Montana Fish, Wildlife, and Parks, Bozeman.

Byorth, P. A. 2000b. Gallatin River drainage trout population surveys: July 1 994 - June 1999, project
3302. Montana Fish, Wildlife, and Parks, Bozeman.

Byorth, P. A. and T. Weiss. 2001. The fishery of Hyalite Reservoir and impacts of raising Hyalite Dam.
Montana Fish, Wildlife, and Parks, Bozeman.

Byorth, P. A. and T. Weiss. 2002. Madison-Gallatin Fisheries Annual Monitoring Report; 2001 . Montana
Fish, Wildlife, and Parks, Bozeman.

Deleray, M. A. 1991 .Movement and utilization of fluvial habitat by Age-0 Arctic grayling, and

characteristics of spawning adults, in the outlet of Deer L^e, Gallatin Coimty, Montana. MS
thesis. Montana State University, Bozeman.

Fox, A. C. 1961. Parasite incidence in relation to size and condition of trout from two Montana Lakes.
M.S. Thesis, Montana State University, Bozeman.

Leik, T. M. 1978 Distribution of the Utah chub fGila atrariaJ in the upper Missouri River System.

Prepared for United States Dept, of the Interior, Bureau of Reclamation. Montana Fish and Game
Dept. Bozeman.

McFarland, R. C. and D. Meredith. 1999. Montana statewide angling pressure mail survey. Montana
Department of Fish, Wildlife, and Parks, Fisheries Information Services, Bozeman.

McFarland, R. C. and D. Meredith. 2000. Montana statewide angling pressure mail survey. Montana
Department .of Fish, Wildlife, and Parks, Fisheries Information Services, Bozeman.

McFarland, R. C. and D. Meredith. 2002. Montana statewide angling pressure mail survey. Montana
Department .of Fish, Wildlife, and Parks, Fisheries Information Services, Bozeman.

Montana Fish, Wildlife and Paries. 2000a. Fisheries program six-year operations plan (200-2006).
Montana Fish, Wildlife, and Parks, Helena.

Ross, J. 1999. America’s 100 best trout streams. Falcon Press. Helena, MT. 351pp.

Sample, M. 1998. Fishing Montana. Falcon Press. Helena, MT. 254 pp.

Shields, R. R. and four co-authors. 1999. Water resources data, Montana, water year 1998. Water-Data
Report MT-98-1 . U.S. Department of Interior, U.S. Geological Survey, Helena.

Vincent, E. R.. 1978. Southwest Montana fisheries study; inventory and survey of the

waters of the Gallatin and Madison drainages. Project F-9-R-26, Job la. Montana Department of
Fish, Wildlife, and Parks, Bozeman.

Vincent, E. R.. 1 979. Southwest Montana fisheries study: inventory and survey of the

waters of the Gallatin and Madison drainages. Project F-9-R-27, Job la. Montana Department of
Fish, Wildlife, and Parks, Bozeman.

Vincent, E. R. and B. Rehwinkle. 1981. Southwest Montana fisheries study: inventory and survey of the

24

waters of the Gallatin and Madison drainages. Project F-9-R-28, Job la. Montana Department of
Fish, Wildlife, and Parks, Bozeman.

Vincent, E. R., with J. Dooley and J. Horn. 1981. Madison River thermal simulation study. Montana
Department of Fish, Wildlife and Parks, Bozeman.

Vincent, E. R. 1987. Effects of stocking catchable-sized hatchery rainbow trout on two wild trout species
in the Madison River and O’Dell Creek, Montana. N. Am. J. Fish. Mgt. 7:91-105.

Vincent. E. R., B. Shepard, W. Fredenberg, and R. Oswald. 1990. Statewide fisheries investigations:
survey and inventory of cold water streams, Southwest Montana major rivers fisheries
investigations. Project F-46-r-3, Job I-f. Montana Fish, Wildlife, and Parks, Bozeman.

Vincent, E.R. 1996. Whirling disease and wild trout: The Montana experience. Fisheries 2 1(6):32-33.

Vincent, R. E. 1962. Biogeographical and ecological factors contributing to the decline of Arctic grayling,
Thymallus arcticus Pallus, in Michigan and Montana. Ph.D. Thesis. University of Michigan, Ann
Arbor.

25

Appendix A. Maps of streams, lakes, and reservoirs displaying study sections.

26

TOPOl map printed on 02/22/02 from "Montana.tpo" and "Untitled, tpg"

111°19.000‘ W 1 11“ 17,000' W 1 1 1** 15.000' W 1 11“ 13.000' W 111“11.000' W WGS84 111°O0,OOO’ W

TOPOl map printed on 02/22/02 from "Montana, tpo" and "Untitled. tpg"
m°16.000' W lll'’14,000' W lll°12.000' W 111“10.000' W 111°O0.OOO' W WGS84 1U°Q5.900' W

TOPO! map printed on 02/2^02 from "Montana. tpo" and "Untitled, tpg"

111°26,000' W lll‘*24,000' W 111“22.000' W 1U"20.000‘ W 111" 18.000' W WGS84 111°15.Q00‘ W

TOPO! map printed on 02/22/02 from "Montana. tpo" and "Untitled. tpg"

iOG' W 111°04,000' W 111°03,000' W WGS84 m°02.0p0* W

TOPOl map printed on 02/22/02 from "Montana, tpo" and "Untitled. tpg"

111°09.000' W 111°08.000' W 111°07.000’ W WGS04 111°06.000'

Priated fromTOPO! ©2000 N^oaal Oeogrtf^c Holdmgs (www.topo.cota)

TOPOl map printed on 02/22/02 from "Montana, tpo" and "Untitled. tpg"

111°38.000‘W 1U°36.000‘ W 111°34.000' W 111°32.000' W 1 11° 30, 000' W WGS84 111°27.000’ W

TOPO! map printed on 02/22/02 from "Montana.tpo" and "Untitled. tpg"

111°41.000‘ W 111°39.000‘ W 1U°37.000' W 111“35.Q00' W 111°33,000’ W WGS84 111°30.000' W

Printed firomTOPOl ©2000 Naticmal Geoff^c Holding (www.topo.coin)

TOPO! map printed on 02/22/02 from "Montana.tpo" and "Untitled. tpg"
lil°40.OOO' W lll°46,0G0' W 11 1® 44. GOO' W 111«42.000' W lll‘'40,000' W WGS64 111®37.000' W

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