Potential for hatchery-wild reproductive interaction from a segregated steelhead hatchery in Washington State Michael Dauer Todd Seamons, Lorenz Hauser, Tom Quinn, Kerry Naish Presented at the Pacific States Marine Fisheries Commission 10 th West Coast Steelhead Meeting March 7-9, 2006

Hatchery Scientific Review Group

Hatchery Reform Models

` Question What risk is involved in the ‘segregated’ hatchery model? Does the mode of segregation (return timing) keep hatchery and wild stocks temporally segregated? Are the hatchery fish reproducing in the wild? Hatchery Wild

Forks Creek Hatchery

Segregated by return timing Adipose fins clipped to differentiate pops Performed parentage Scales analyzed

Separation by Adipose Fin Clipping Animalpicturesarchive.com Water Flow Hatchery Willapa River Forks Creek Water Flow

Animalpicturesarchive.com Water Flow Willapa River Forks Creek Water Flow Separation by Adipose Fin Clipping Hatchery

Animalpicturesarchive.com Water Flow Willapa River Forks Creek Water Flow Separation by Adipose Fin Clipping Hatchery X

Animalpicturesarchive.com Water Flow Willapa River Forks Creek Water Flow Separation by Adipose Fin Clipping Hatchery X X

Separation by Spawn Timing

Todd Seamons, unpublished data

Separation by Spawn Timing

` Question What risk is involved in the ‘segregated’ hatchery model? Does the mode of segregation (return timing) keep hatchery and wild stocks temporally segregated? Are the hatchery fish reproducing in the wild? <5% breeders in wild Hatchery Wild Ford, 2002; Mobrand et al, 2005

Scale Analysis

Do these stocks differ at age of return? Ocean Scale Analysis T-test p=0.013; df=88

Do these stocks differ at age of return? T-test p<0.001; df=88 Freshwater Scale Analysis Photo Courtesy of Tom Quinn

Do these stocks differ at age of return? Rate of Iteroparity (Repeat Spawning)

N Wild, t N Hatchery, t Iteroparity in time=t tells us about N Hatchery fish in wild, t-1 N Hatchery fish in wild, t N total fish in wild, t Goal: <5% Ford, 2002; Mobrand et al, 2005 Predicting H/W ratio in the wild environment

N Hatchery fish in wild, t N Total fish in wild, t Goal: <5% 10% 130

Predicting H/W ratio in the wild environment Goal: <5% 20% 160 N Hatchery fish in wild, t N Total fish in wild, t

Predicting H/W ratio in the wild environment Redd Counts (WDFW in Mackey et al. 2001)

Predicting H/W ratio in the wild environment Goal: <5% 20% 160 % N Hatchery fish in wild, t N Total fish in wild, t

44.8% Predicting H/W ratio in the wild environment Conservative estimates: Repeat spawner success = 10% Wild Sampling Success = 20% N Hatchery fish in wild, t N Wild population, t Goal: <5%

Predicting H/W ratio in the wild environment Bottom Line: Unlikely that we are meeting the <5% goal of the segregated hatchery model

Conclusions Segregated hatchery model requires minimal reproductive interactionSegregated hatchery model requires minimal reproductive interaction There is potential for considerable interaction due to iteroparity in hatchery fishThere is potential for considerable interaction due to iteroparity in hatchery fish

Conclusions However – These ratios do not elucidate the true ecological or evolutionary impactHowever – These ratios do not elucidate the true ecological or evolutionary impact Mackey et al showed little spatial overlapMackey et al showed little spatial overlap Not N e, just census estimateNot N e, just census estimate Only provide us an upper estimate of the potential impactOnly provide us an upper estimate of the potential impact

Future Directions Reproductive success of hatchery fish in wildReproductive success of hatchery fish in wild Smolt samplesSmolt samples Rate of evolution in hatcheryRate of evolution in hatchery Examine life history of putative hybridsExamine life history of putative hybrids

Acknowledgments Committee – Kerry Naish, Tom Quinn, Lorenz Hauser Peer Support – Todd Seamons, Jason Cope, Jim Franks, fishMMBL, Quinn Group Scale Reading – Kate Myers, Jan Armstrong, Nancy Davis, and Trey Walker (High Seas Salmon Program) Hatchery Staff – Rob Allen, Kevin Flowers, Dave Shores, Merle Hash, Jenny Allen Lab Help – Lyndsay Newton, Duy Mai, Louise Baxter Funding – BPA, Wild Steelhead Coalition

Do these stocks differ at age of return?

Do these stocks differ at fitness related traits? T-test ** p<0.001 * p<0.05

` Question What reproductive risk is involved in the ‘segregated’ hatchery model? Do segregated hatcheries keep hatchery and wild stocks reproductively isolated? Less than 5% wild spawners Hatchery Wild Ford, 2002; Mobrand et al, 2005