Hatchery Steelhead Kelt Reconditioning at Dworshak National Fish Hatchery: A Model for B Run Steelhead
Steelhead, the anadromous form of rainbow trout, are capable of repeat spawning (iteroparity). Snake River steelhead have historically been classified as A-run and B-run: B-run fish usually spend 2 or more winters in the ocean and are therefore larger than the 1-sea winter A-runs. Current populations and iteroparity rates of wild B-run steelhead in the Snake River system are severely depressed due to the operation of hydroelectric dams and other anthropogenic factors, leading to ESA listing of these stocks and recovery plans. One recovery method is kelt reconditioning: the capture of post spawn fish (kelts), reconditioning of fish in a captive environment, and release of rematuring fish into rivers to spawn naturally. To enable studies of kelt reconditioning using B-run steelhead, a hatchery model has been developed in collaboration with the US Fish and Wildlife Service and the Nez Perce Tribe at Dworshak National Fish Hatchery. Hatchery ladder returning steelhead females are non-lethally spawned and transferred to 4.6 m diameter circular tanks, treated for diseases and parasites, and fed krill and pellets. Current spawning methods, fish holding facilities, and fish culture techniques will be described, and kelt survival profiles will be presented.
Graham, N.D., S.R. Everett, R. Branstetter, L.E. Jenkins, A.L. Pierce, and D.R. Hatch. 2015. Effects of Captive Reconditioning and Post-Spawning Life History on Reproductive Performance Hatchery Steelhead Kelt Reconditioning at Dworshak National Fish Hatchery: A Model for B Run Steelhead. American Fisheries Society Annual Conference, Portland, OR, August 2015.
Aug 17th, 2015