present in snake, clearwater, and salmon river drainages provide valuable fishery well documented...
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Present in Snake, Clearwater, Present in Snake, Clearwater, and Salmon River drainagesand Salmon River drainages
Provide valuable fishery Provide valuable fishery
Well documented variation in Well documented variation in ocean life history (A vs B run)ocean life history (A vs B run)
High variation in freshwater High variation in freshwater habitat characteristicshabitat characteristics
Freshwater life history not Freshwater life history not extensively studied in Idahoextensively studied in Idaho
ESA listed in 1997ESA listed in 1997
AbundanceAbundanceHow many of them are How many of them are
there?there?
ProductivityProductivityHow well do they How well do they
reproduce & survive?reproduce & survive?
Spatial structureSpatial structureWhere are they?Where are they?
DiversityDiversityWhat are they like?What are they like?
No population specific No population specific datadata
Used aggregate A-run, B-Used aggregate A-run, B-run data for adults at run data for adults at Lower Granite DamLower Granite Dam Divided abundance to Divided abundance to
population within run-typepopulation within run-type Assumed all had same run-Assumed all had same run-
type productivitytype productivity Limited information on life Limited information on life
history or spatial history or spatial structurestructure
Compare/contrast freshwater life history dataCompare/contrast freshwater life history data
Examine implications for population Examine implications for population productivityproductivity
East Fork Potlatch East Fork Potlatch RiverRiver
Crooked Fork Crooked Fork CreekCreek
Fish CreekFish Creek
Rapid RiverRapid River
Big Bear CreekBig Bear Creek
Little SalmonLittle Salmon(A-run)(A-run)
Lower Lower ClearwaterClearwater
(A-run)(A-run)LochsaLochsa(B-run)(B-run)
StreamElevation
(ft)
Annual Precipitatio
n (in)Geology Land use
Big Bear Creek
1200-4983 22-30Loess/
volcanic ashAgriculture
East Fork Potlatch
River2685-4400 22-45
Volcanic ash/loess
Forestry
Fish Creek 2000-6540 30-55Volcanic
ash/graniteLimited Forestry
Crooked Fork Creek
3442-6340 35-55Volcanic
ash/graniteForestry
Rapid River 2100-8660 14-30Colluvium/
basaltWilderness
Use 2008 emigrant data from screw trapsUse 2008 emigrant data from screw traps Abundance, scale samples, PIT tagsAbundance, scale samples, PIT tags
MetricsMetrics Emigrant abundanceEmigrant abundance
Timing from natal streamTiming from natal stream
Age compositionAge composition
Length at ageLength at age
Detections in Snake/Columbia hydrosystemDetections in Snake/Columbia hydrosystem
Compare/contrast freshwater life history Compare/contrast freshwater life history datadata
Stream Spring Summer Fall
Big Bear Creek
3,492 1,245 670
East Fork Potlatch River
1,912 2,706 3,749
Fish Creek 751 3,236 11,960
Crooked Fork 63,679 37,879 3,431
Rapid River 2,380 1,121 1,664
SprinSpringgSummeSummerrFallFall
Age -0Age -0
Age -1Age -1
Age -2Age -2
Age -3Age -3
Age -4Age -4
Stream Spring tagsSummer
tagsFall tags
Big Bear Creek
0.54 0.16 0.13
East Fork Potlatch River
0.27 0.20 0.16
Fish Creek 0.40 0.35 0.43
Crooked Fork Creek
0.62 0.41 0.55
Rapid River 0.54 0.04 0.33
• Spring tags detected in year of tagging (Sp 2008)Spring tags detected in year of tagging (Sp 2008)• Summer and fall tags detected year after tagging (Sp Summer and fall tags detected year after tagging (Sp 2009)2009)
A variety of life history strategies A variety of life history strategies observed between the populationsobserved between the populations
Juvenile rearing completed within natal Juvenile rearing completed within natal streams and downstream reachesstreams and downstream reaches
Lower elevation populations have Lower elevation populations have younger age structure than high younger age structure than high elevationelevation
Examine implications for population Examine implications for population productivityproductivity
Use abundance, age structure, & Use abundance, age structure, & assumed survival to estimate initial fry assumed survival to estimate initial fry abundanceabundance
Use abundance & apparent migration Use abundance & apparent migration survival to LGD to estimate smolt survival to LGD to estimate smolt productionproduction
Productivity measure is smolts per fryProductivity measure is smolts per fry
Natal Stream Annual Survival
Stream S = 0.5 S = 0.33
Big Bear Creek 0.138 (1.00) 0.066 (1.00)
EFK Potlatch River 0.083 (0.60) 0.045 (0.68)
Fish Creek 0.106 (0.77) 0.042 (0.63)
Crooked Fork 0.074 (0.54) 0.019 (0.29)
Rapid River 0.058 (0.42) 0.017 (0.26)
• Survival Relative to Big Bear Creek in Survival Relative to Big Bear Creek in parenthesesparentheses
Productivity differences within Technical Productivity differences within Technical Recovery Team populations Recovery Team populations (Fish Cr v. Crooked Fk / Big Bear v. EFK Potlatch)(Fish Cr v. Crooked Fk / Big Bear v. EFK Potlatch)
Decreasing natal stream survival increases Decreasing natal stream survival increases relative advantage of Big Bear & EFK relative advantage of Big Bear & EFK PotlatchPotlatch
B-run populations need increased smolt-B-run populations need increased smolt-adult survival & fecundities to make up for adult survival & fecundities to make up for older age structureolder age structure
Variation in freshwater life history Variation in freshwater life history important to population stabilityimportant to population stability
Low elevation populations very resilientLow elevation populations very resilient Results similar to genetic & parr density Results similar to genetic & parr density
studiesstudies
High “value” of habitat restoration High “value” of habitat restoration projects for lower elevation populationsprojects for lower elevation populations
Further investigations of high elevation Further investigations of high elevation & Salmon River populations& Salmon River populations