title: Disease Susceptibility of Hatchery Snake River Spring-Summer Chinook Salmon with Different Juvenile Migration Histories in the Columbia River.
abstract: Various methods have been developed to mitigate the effects of dams on juvenile Pacific salmon Oncorhynchus spp. migrating to the Pacific Ocean through the Columbia River basin. In this study, we examined the health of hatchery Snake River spring and summer Chinook salmon relative to two mitigating strategies: dam bypass and transportation (e.g., barging). The health of out-migrants was assessed in terms of the difference in the incidence of mortality among fish, categorically grouped into no-bypass, bypass, and transportation life histories, in response to challenge with the marine pathogen Listonella anguillarum during seawater holding. These three life histories were defined as follows: (1) fish that were not detected at any of the juvenile bypass systems above Bonneville Dam were classified as having a no-bypass life history; (2) fish that were detected at one or more juvenile bypass systems above Bonneville Dam were classified as having a bypass life history; and (3) fish that were barged were classified as having the transportation life history. Barged fish were found to be less susceptible to L. anguillarum than in-river fish-whether bypassed or not-which suggests that transportation may help mitigate the adverse health effects of the hydropower system of the Columbia River basin on Snake River spring-summer Chinook salmon. The findings of this study are not necessarily transferable to other out-migrant stocks in the Columbia River basin, given that only one evolutionarily significant unit, that is, Snake River spring-summer Chinook salmon, was used in this study.
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Mary R
authors.initials: MR
authors.lastname: Arkoosh
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Anna N
authors.initials: AN
authors.lastname: Kagley
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Bernadita F
authors.initials: BF
authors.lastname: Anulacion
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Deborah A
authors.initials: DA
authors.lastname: Boylen
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Sandford
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.|b Department of Civil and Environmental Engineering , University of California-Davis , 1 Shields Avenue , Davis , California , 95616 , USA.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Loge
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Lyndal L
authors.initials: LL
authors.lastname: Johnson
authors.affiliation: a National Marine Fisheries Service, Northwest Fisheries Science Center , 2030 South Marine Science Drive , Newport , Oregon , 97365 , USA.
authors.forename: Tracy K
authors.initials: TK
authors.lastname: Collier