Because of their long-term listing under the Endangered Species Act, much interest has been placed on estimating population vital rates for Bull Trout Salvelinus confluentus, but the biotic and abiotic factors that influence the interannual variability in those vital rates have rarely been evaluated. We used mark-recapture data to estimate fish growth, survival, and trends in abundance for fluvial adult Bull Trout in the East Fork Salmon River, Idaho. Over an 8-year period, a total of 1,205 individual Bull Trout were collected at a weir on the East Fork Salmon River (29 km upstream of its confluence with the Salmon River) during June-September, of which 420 were recaptures from prior years. Bull Trout varied in length from 215 to 756 mm and achieved a slightly larger asymptotic length and a slightly lower rate of growth relative to other fluvial and adfluvial Bull Trout populations. Apparent survival averaged 0.42 across all years, which was similar to previous studies estimating apparent survival for Bull Trout. The number of emigrating anadromous salmonid smolts in the upper Salmon River basin positively influenced East Fork Salmon River Bull Trout growth and survival, and survival was higher in years with lower annual discharge. Assessment of population growth via linear regression analysis indicated that the Bull Trout population was increasing during the study period (λ = 1.08; 95% confidence interval = 1.03-1.14). Our findings highlight the ecological link between the abundance of wild and hatchery Chinook Salmon Oncorhynchus tshawytscha, Sockeye Salmon O. nerka, and steelhead O. mykiss smolts and growth and survival of adult Bull Trout in systems where these species occur in sympatry.Bull Trout Salvelinus confluentus is a species of char native to western North America that has been listed as threatened by the U.S. Fish and Wildlife Service under the Endangered Species Act since 1999 (USFWS 1999). Bull Trout are large compared with most salmonids, achieving lengths of 700-900 mm and weights of >10 kg, and they commonly live from 8 to 12 years (Sigler and Zaroban 2018). The diet of Bull Trout changes with age, with younger Bull Trout feeding on invertebrates and older Bull Trout tending to be piscivorous. Bull Trout typically mature at 4-7 years of age, with spawning occurring in autumn when water temperatures are below 9°C, primarily in headwater mountain streams.Understanding the viability of threatened or endangered fish populations or assessing the effectiveness of management strategies or habitat restoration to conserve at-risk

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