280 likes | 379 Views
The road to extinction is paved with good intentions: Can hatchery and natural salmon co-exist?. Rachel C. Johnson Cramer Fish Sciences & University of California Davis. Chinook salmon runs. Extinct. At Risk. Special concern. Low or No Risk. Not Evaluated. Salmon of the past.
E N D
The road to extinction is paved with good intentions: Can hatchery and natural salmon co-exist? Rachel C. Johnson Cramer Fish Sciences & University of California Davis
Chinook salmon runs Extinct At Risk Special concern Low or No Risk Not Evaluated Salmon of the past Sabertooth salmon, Oncorhynchus rastrosus Twelve million years ago 400 pounds; 8-10 feet in length
California salmon in the present Adult Spawn Time Evolutionarily Significant Units Fall run Candidate Late Fall run Candidate Winter run Endangered Spring run Threatened Steelhead Threatened J A S O N D J F M A M J Data sources: Vogel and Marine, 1991; Hallock, 1983; CDFG, 1993
California Chinook salmon trend 2,000,000 1,000,000 500,000 400,000 300,000 200,000 100,000 Dams Habitat Estimated spawner escapement Harvest 1850 1950 2000 Hatcheries Year Courtesy of Joe Merz, Cramer Fish Sciences
Reliance on hatcheries for harvest wild contribution 90% ± 6% 2002 Barnett-Johnson et al., 2007. Canadian Journal of Fisheries and Aquatic Sciences
Reliance on hatcheries for harvest wild contribution Wild (Hatchery) 90% ± 6% 55% 52% 2002 2010 2011 Barnett-Johnson et al., 2007. Canadian Journal of Fisheries and Aquatic Sciences Kormos et al., 2012. Fisheries Branch Administrative Report Palmer-Zwahlen and Kormos. 2013. Fisheries Branch Administrative Report
‘Optimal’ hatchery releases for harvest Coleman National Fish Hatchery 2011 Ocean Recoveries Bay releases In-river releases recoveries per 100,000 released Brood years Data source: Palmer-Zwahlen & Kormos. 2013
‘Non-Optimal’ consequence to natural salmon Stray Homing Bay releases In-river releases recoveries per 100,000 released Brood years Brood years Coleman National Fish Hatchery 2011 Recovery rates Data source: Palmer-Zwahlen & Kormos 2013
Fitness Effects and Domestication selection Hatchery fish spawning in the wild… Hatchery fish spawning in hatcheries... Double lifetime reproductive success compared to wild spawned in captivity 40% reduction in fitness per captive generation Araki et al. 2007 Science Christie et al. 2012 PNAS
Where do the un-harvested hatchery fish return? Wild (Hatchery) Wild (Hatchery) Battle Creek BAT (CNH) Mill Creek 2002 2010 2011 MIL/DEE Deer Creek FRH (FRH) Feather American AME (NIH) 90% ± 6% 55% 52% Mokelumne MOK (MOH) Stanislaus STA Tuolumne ~870,000 ~160,000 ~230,000 TUO Merced MER (MEH) Escapement Data sources: Barnett-Johnson et al. 2007, Kormos et al. 2012, Palmer-Zwahlen and Kormos. 2013, Grandtab 2013
Hatchery-origin fish return to hatcheries 2010 Coleman Hatchery origin Feather Natural origin Nimbus Mokelumne Merced Fall run Chinook salmon escapement to hatcheries Data source: Kormos et al. 2013, Palmer-Zwahlen & Kormos. 2013
Hatchery-origin fish return to hatcheries 2010 Coleman Coleman Nimbus Hatchery origin Feather Feather Natural origin Nimbus Mokelumne Mokelumne Merced Fall run Chinook salmon escapement to hatcheries Data source: Kormos et al. 2013, Palmer-Zwahlen & Kormos. 2013
Many hatchery fish spawn in rivers 2010 2011 Butte Creek Butte Creek Clear Creek Upper Sacramento Clear Creek Upper Sacramento Feather River Feather River Cottonwood Creek Yuba River Yuba River 60% 0 70% Hatchery origin Hatchery origin American River American River Natural origin Natural origin Mokelumne River Mokelumne River Stanislaus River Stanislaus River Tuolumne River Tuolumne River Merced River Merced River
Extinction risk due to hatchery influence Strays from within basin High risk Moderate risk Low risk % Hatchery spawners Generation Generations In Lindley et al. 2007 Interior Columbia Basin Tech. Recovery Team 2005
Majority of salmon spawn in natural areas Hatchery spawners In-river spawners Number of fall-run Years Grandtab 2013
Majority of salmon spawn in natural areas Hatchery spawners In-river spawners Number of fall-run Years Grandtab 2013
Cohort replacement rates of natural populations Cohort replacement
Conclusions • Off-site releases- harvest vs. straying • Identification of hatchery fish • HSRG criteria currently unmet for hatcheries • Hatchery strays contribute to ‘high’ risk of extinction • Management scenarios
Thanks! Special thanks to: Brett Kormos & Melodie Palmer-Zwahlen California Department of Fish and Wildlife Ocean Salmon Project
Hatchery Scientific Review Group’s Issues/Recommendations (14) Issue: Off-site releases promote unacceptable levels of straying among populations Recommendation: In-river release of juvenile hatchery production 1. Issue: Marking/tagging programs are needed for real-time identification of all hatchery Chinook salmon Recommendation: Tag 100% of hatchery production with coded-wire-tags and 25% should be adipose fin-clipped 2. Issue: Harvest management of fall-run Chinook salmon should account for productivity of naturally spawning adults Recommendation: Revise harvest rate to explicitly account for the status and productivity of fall Chinook salmon spawning in natural areas 3. California Hatchery Review Project, June 2012
Genetically distinct ‘ecotypes’ in Lake Washington Deep-bodied beach type Slender river type Science 2000
Hatchery-origin fish do return to hatcheries 2010 2011 Coleman Coleman Feather Hatchery origin Feather Natural origin Nimbus Nimbus Mokelumne Mokelumne Merced Merced Fall run Chinook salmon escapement to hatcheries Data source: Kormos et al. 2013, Palmer-Zwahlen & Kormos. 2013
Many hatchery fish spawn in rivers 2010 Butte Creek Clear Creek Upper Sacramento Feather River Yuba River Hatchery origin American River Natural origin Mokelumne River Stanislaus River Tuolumne River Merced River
California Chinook salmon trend 2,000,000 1,000,000 500,000 400,000 300,000 200,000 100,000 Dams Habitat Estimated spawner escapement Harvest Hatcheries 1850 1950 2000 Year Courtesy of Joe Merz, Cramer Fish Sciences