In Search of the Lost In Search of the Lost LegionsLegions

Attempting to account for Attempting to account for Hatchery-origin steelhead Hatchery-origin steelhead returns to the Snake Riverreturns to the Snake River

Herb Pollard – NOAA –National Marine Fisheries Service

Chris Starr – USFWS – Lower Snake Compensation Plan

Estimated Snake River steelhead smolt outmigrants at Lower Granite

Dam

0

2000000

4000000

6000000

8000000

Years 1999-2004

Nu

mb

er

Hatchery Origin

Natural Origin

Hatchery-origin : Wild/natural Hatchery-origin : Wild/natural Steelhead Run Composition at Steelhead Run Composition at Lower Granite Dam 1984-2003Lower Granite Dam 1984-2003

Hatchery-origin

Wild/natural

050000

100000150000

200000250000

300000

1984-1985

1987-1988

1990-1991

1993-1994

1996-1997

1999-2000

2002-2003

Hatchery-origin steelhead

Natural-origin Steelhead

Hatchery-origin : Wild/natural Hatchery-origin : Wild/natural Steelhead Run % Composition at Steelhead Run % Composition at Lower Granite Dam 1984-2003Lower Granite Dam 1984-2003

Hatchery-origin steelhead

Natural-origin steelhead

0%

20%

40%

60%

80%

100%

84-8

5

86-8

7

88-8

9

90-9

1

92-9

3

94-9

5

96-9

7

98-9

9

00-0

102

03

Hatchery-origin steelhead adults

Natural-origin steelhead adults

Concerns about Hatchery-origin Concerns about Hatchery-origin Steelhead Adult ReturnsSteelhead Adult Returns

Genetic concerns:Genetic concerns:• Artificial selectionArtificial selection• Genetic introgressionGenetic introgression• Loss of fitnessLoss of fitness

Ecological ConcernsEcological Concerns• Competition for mates or spawning Competition for mates or spawning

areasareas

Sometimes these concerns are Sometimes these concerns are expressed as:expressed as:

““There are Tens of Thousands of There are Tens of Thousands of unaccounted hatchery steelhead in the unaccounted hatchery steelhead in the Snake River Basin!”Snake River Basin!”

““Hatchery steelhead stray randomly and Hatchery steelhead stray randomly and impact wild steelhead throughout the impact wild steelhead throughout the basin!”basin!”

““Hatchery strays are spawning with wild Hatchery strays are spawning with wild fish in important natural production areas, fish in important natural production areas, reducing fitness and adversely impacting reducing fitness and adversely impacting recovery!”recovery!”

Concerns for Hatchery strays in Concerns for Hatchery strays in status reviews and recovery status reviews and recovery

literatureliterature

But, really, not much is But, really, not much is known about the impact of known about the impact of hatchery fish on natural hatchery fish on natural steelhead in the Snake steelhead in the Snake River basin.River basin.

The Assignment to Fishery The Assignment to Fishery Managers:Managers:

Account for the hatchery-origin Account for the hatchery-origin steelhead that return to known sites steelhead that return to known sites and harvestand harvest

Summarize the data for hatchery-Summarize the data for hatchery-origin steelhead that stray between origin steelhead that stray between release sites or into natural release sites or into natural production areas production areas

Data on known removals/mortalitiesData on known removals/mortalities

Hatchery rack returnsHatchery rack returns Harvest estimates/creel censusHarvest estimates/creel census Natural mortalityNatural mortality Return to direct stream releasesReturn to direct stream releases Catch and release mortality in Catch and release mortality in

recreational fisheriesrecreational fisheries

Data on known strays/tag Data on known strays/tag recoveriesrecoveries

Wild steelhead weirs in Grande Wild steelhead weirs in Grande Ronde, Imnaha, and Lochsa systemsRonde, Imnaha, and Lochsa systems

Hatchery weirsHatchery weirs Coded-wire tag returns from weirs Coded-wire tag returns from weirs

and fisheriesand fisheries

Genetic Evidence of hatchery Genetic Evidence of hatchery introgression into natural introgression into natural

populationspopulations

IDFG Steelhead Genetic SurveyIDFG Steelhead Genetic Survey NMFS Northwest Fishery Science NMFS Northwest Fishery Science

Center surveysCenter surveys

CooperatorsCooperators Washington Department of Fish and Wildlife – Washington Department of Fish and Wildlife –

Mark SchuckMark Schuck Oregon Department of Fish and Wildlife – Rich Oregon Department of Fish and Wildlife – Rich

CarmichaelCarmichael Idaho Department of Fish and Game – Paul KlineIdaho Department of Fish and Game – Paul Kline Nez Perce Tribal Fisheries – Becky JohnsonNez Perce Tribal Fisheries – Becky Johnson Shoshone-Bannock Tribal Fisheries – Keith Shoshone-Bannock Tribal Fisheries – Keith

KutchinsKutchins Confederated Tribes of the Umatilla Indian Confederated Tribes of the Umatilla Indian

Reservation – Brian ZimmermanReservation – Brian Zimmerman

How many fish can be How many fish can be accounted for?accounted for?

Harvest

Hatchery

Direct Release

C&R

Natural

Unaccounted

Harvest

Hatchery

Direct Release

C&R

Natural

Unaccounted

Harvest

Hatchery

Direct Release

C&R

Natural

Unaccounted

Harvest

Hatchery

Direct Release

C&R

Natural

Unaccounted

Harvest

Hatchery

Direct Release

C&R

Natural

Unaccounted

Harvest

Hatchery

Direct Release

C&R

Natural

Unaccounted

Distribution of Hatchery-origin Steelhead in Distribution of Hatchery-origin Steelhead in the Snake River 1995-2002the Snake River 1995-2002

Weighted AverageWeighted Average

Harvest 60.9%

Hatchery Rack 19.1%Direct Stream 8.7%

Natural Mortality 6.4% C&R mortality 0.8%

Unaccounted 4.1%

Distribution of Hatchery-origin Steelhead in Distribution of Hatchery-origin Steelhead in the Snake River 1995-2002the Snake River 1995-2002

-50%

0%

50%

100%

95-96

96-97

97-98

98-99

99-00

00-01

0102

Unaccounted

Direct Stream

Natural mort

C&R mort

Hatchery

Harvest

0

10000

20000

30000

40000

50000

60000

95-6 96-7 97-8 98-9 99-00 00-01 01 02

Unaccounted HOR

NOR Escapement

So, where do they go?So, where do they go?

Numbers of natural-origin adult steelhead and hatchery-Numbers of natural-origin adult steelhead and hatchery-origin strays trapped at Grande Ronde River tributary weirs, origin strays trapped at Grande Ronde River tributary weirs,

2001-2004 (Data from Mike McLean, CTUIR2001-2004 (Data from Mike McLean, CTUIR) ) Weir Site Run Year

2001-02 2002-03 2003-04 Total (Strays)

Lookingglass Creek

258 165 134 557 (4)

Upper Grande Ronde

36 56 63 155 (1)

Catherine Creek 256 226 181 663 (3)

Total (Strays) 550 (5) 447 (1) 378 (2) 1,375 (8)

Proportion of Hatchery-origin Proportion of Hatchery-origin steelhead strays at three weirs in steelhead strays at three weirs in

the upper Grande Ronde Subbasinthe upper Grande Ronde Subbasin

1,367 Wild/natural fish – 99.4%

8 Hatchery strays – 0.6%

Stray rates in the Imnaha Basin 1999-00 to 2003-04 run Stray rates in the Imnaha Basin 1999-00 to 2003-04 run

years. Courtesy of Jay Hesse (Nez Perce Tribe).years. Courtesy of Jay Hesse (Nez Perce Tribe).

Lightning Stray rate Cow Stray rate Stray rate

Run year Escapement Creek (%) Creek (%) SGS (%)

1999-00 445 2 0.0045 -- 0 0.0000

2000-01 1,224 2 0.0016 4 0.0033 0 0.0000

2001-02 3,775 8 0.0021 15 0.0040 0 0.0000

2002-03 2,417 7 0.0029 4 0.0017 3 0.0012

2003-04 3,502 8 0.0023 20 0.0057 1 0.0003

Imnaha Hatchery Returns and Imnaha Hatchery Returns and strays in Tributariesstrays in Tributaries

11,363 Hatchery returns – 1999-04

74 Hatchery Strays detected in Tributaries

Fish Creek Weir: Hatchery StraysFish Creek Weir: Hatchery Strays

0

100

200

300

400

95-96 96-97 97-98 98-99 99-00 00-01 01 02 02 03 03 04

Hatchery-origin strays ~2%

Natural-origin recruits

Rapid River Weir NOR:HORRapid River Weir NOR:HOR

0

100

200

300

400

95-96 96-97 97-98 98-99 99-00 00-01 01 02 02 03 03 04

HOR

NOR

How well do the hatchery How well do the hatchery fish return to the point of fish return to the point of release?release?

Cottonwood Pond – 4,515 CWTCottonwood Pond – 4,515 CWTrecovered in the Snake River Basinrecovered in the Snake River Basin

Snake River Sport – 1,628

Grande Ronde Sport – 1,936

Cottonwood Trap - 781

Lyons Ferry Trap - 110 Others – 60 (1.3%) Clearwater Sport – 11 Tucannon Sport – 13 Salmon Sport - 30 Pahsimeroi – 1 Big Canyon - 5

Wallowa-Big Canyon 4,361 CWT Wallowa-Big Canyon 4,361 CWT Recovered in the Wallowa RiverRecovered in the Wallowa River

Returned to Site of Release – 4,348

Strays between Facilities - 13

Idaho Rack and Harvest Recovery Idaho Rack and Harvest Recovery of fish released at racks – 6,361 of fish released at racks – 6,361 CWT recovered in Snake riverCWT recovered in Snake river

OK – Fish recovered at the release site or in fisheries downstream and en route - 6,324 tags

Not OK – Fish recovered at the wrong hatchery rack or in fisheries off the direct route – 37 tags (0.6%)

IDFG Direct Stream Releases IDFG Direct Stream Releases 1,153 CWT1,153 CWT

OK – Recovered in area of release - 916 tags (79.5%)

Out-of-Subbasin– downstream – 37 tags (3.0%)

In-subbasin -downstream – 48 tags (4.0 %)

In-subbasin – upstream 152 tags (13.2%)

Genetic SurveysGenetic Surveys

Genetic Population Structure of Genetic Population Structure of Snake River Basin Steelhead in Idaho Snake River Basin Steelhead in Idaho (Nielsen et al 2004) : (Nielsen et al 2004) :

“…“…significant genetic population significant genetic population structure remains for steelhead structure remains for steelhead populations within the Snake populations within the Snake River…”River…”

Conclusion: Fishery managers know Conclusion: Fishery managers know where most of the hatchery origin where most of the hatchery origin

steelhead go in the Snake River Basin.steelhead go in the Snake River Basin.

On the average, 95.9% of the On the average, 95.9% of the hatchery steelhead passing Lower hatchery steelhead passing Lower Granite Dam are accounted in Granite Dam are accounted in harvest, rack returns, natural harvest, rack returns, natural mortality and returns to sites like the mortality and returns to sites like the Little Salmon River. The number of Little Salmon River. The number of unaccounted fish is much smaller unaccounted fish is much smaller than has been thought.than has been thought.

Conclusion: Once within the Snake Conclusion: Once within the Snake River Basin, hatchery-origin River Basin, hatchery-origin

steelhead demonstrate a high steelhead demonstrate a high degree of homing fidelity. degree of homing fidelity.

CWT detections indicate >90% CWT detections indicate >90% return to release sitesreturn to release sites

Stray rates between facilities or in Stray rates between facilities or in fishery detections are small.fishery detections are small.

Conclusion: Conclusion: Detection of Hatchery Detection of Hatchery strays in natural production areas is strays in natural production areas is

less than suspectedless than suspected

Weirs located on wild steelhead Weirs located on wild steelhead streams catch few hatchery fish, streams catch few hatchery fish, hatchery fish are seldom hatchery fish are seldom observed in spawning grounds observed in spawning grounds surveys, and the ongoing genetic surveys, and the ongoing genetic surveys have not reported surveys have not reported widespread occurrence of the widespread occurrence of the hatchery stockshatchery stocks..

Uncertainties remain . . .Uncertainties remain . . .

There are weirs on only a few of the There are weirs on only a few of the important wild production streams – important wild production streams – What about the others?What about the others?

If the few hatchery strays arrive in If the few hatchery strays arrive in natural spawning areas, how natural spawning areas, how successful are they – what are the successful are they – what are the impacts?impacts?

However…..However…..

Empirical data is fairly abundant and Empirical data is fairly abundant and robust to indicate that straying of robust to indicate that straying of large numbers of hatchery steelhead large numbers of hatchery steelhead into important natural production into important natural production areas does not occur within the areas does not occur within the Snake River basin at the level Snake River basin at the level previously thought.previously thought.

Management ImplicationsManagement Implications

Geographic isolation of hatchery Geographic isolation of hatchery steelhead can be an effective steelhead can be an effective management measuremanagement measure• Release fish in main stems, away from Release fish in main stems, away from

important tributary spawning areasimportant tributary spawning areas• Release fish in areas with good public Release fish in areas with good public

access to increase harvest ratesaccess to increase harvest rates

Management ImplicationsManagement Implications

Steelhead exhibit strong homing Steelhead exhibit strong homing fidelity to release sites, but…fidelity to release sites, but…• There may be a tendency to stray There may be a tendency to stray

upstream or into nearby tributaries if upstream or into nearby tributaries if fish are not removedfish are not removed

Management ImplicationsManagement Implications

Acclimation ponds may not be Acclimation ponds may not be necessary, but…necessary, but…• Release at a pond or tributary weir will Release at a pond or tributary weir will

likely help with accounting for returnslikely help with accounting for returns• Acclimation ponds allow management Acclimation ponds allow management

options with non-migratory “residual” options with non-migratory “residual” malesmales

Thank you…Thank you…

Any Questions?Any Questions?

Herb Pollard, NOAA Fisheries NW Region, Herb Pollard, NOAA Fisheries NW Region, Hatcheries and Inland Fisheries BranchHatcheries and Inland Fisheries Branch

Chris Starr, US Fish and Wildlife Service, Lower Chris Starr, US Fish and Wildlife Service, Lower Snake River Compensation PlanSnake River Compensation Plan