|Document Type:||Journal Article|
|Title:||Variation in the Early Marine Survival and Behavior of Natural and Hatchery-Reared Hood Canal Steelhead|
|Author:||M. E. Moore, B. A. Berejikian, E. P. Tezak|
|Keywords:||telemetry,hatchery-wild,Puget Sound,marine survival,Hood Canal,migration behavior|
Hatchery-induced selection and direct effects of the culture environment can both cause captively bred fish populations to survive at low rates and behave unnaturally in the wild. New approaches to fish rearing in conservation hatcheries seek to reduce hatchery-induced selection, maintain genetic resources, and improve the survival of released fish.
This study used acoustic telemetry to compare three years of early marine survival estimates for two wild steelhead populations to survival of two populations raised at two different conservation hatcheries located within the Hood Canal watershed. Steelhead smolts from one conservation hatchery survived with probabilities similar to the two wild populations (freshwater: 95.8–96.9%, early marine: 10.0–15.9%), while smolts from the other conservation hatchery exhibited reduced freshwater and early marine survival (freshwater: 50.2–58.7%, early marine: 2.6–5.1%). Freshwater and marine travel rates did not differ significantly between wild and hatchery individuals from the same stock, though hatchery smolts did display reduced migration ranges within Hood Canal. Between-hatchery differences in rearing density and vessel geometry likely affected survival and behavior after release and contributed to greater variation between hatcheries than between wild populations.
Our results suggest that hatchery-reared smolts can achieve early marine survival rates similar to wild smolt survival rates, and that migration performance of hatchery-reared steelhead can vary substantially depending on the environmental conditions and practices employed during captivity.
This paper describes the behavior and provides segment-specific survival estimates for hatchery and wild steelhead smolts migrating from Hood Canal streams to the open ocean. Variation between hatchery populations exceeded variation between wild populations, emphacizing the importance of hatchery rearing conditions on released smolt performance.
|Theme:||Recovery and rebuilding of marine and coastal species|
Evaluate the effects of artificial propagation on recovery, rebuilding and sustainability of marine and anadromous species.
Moore M, Berejikian BA, Tezak EP (2012) Variation in the Early Marine Survival and Behavior of Natural and Hatchery-Reared Hood Canal Steelhead. PLoS One 7(11): e49645. doi:10.1371/journal.pone.0049645