Bristol Bay Sockeye Salmon Parent Escapement/Return and Smolt Data, 1949-2009, Ruggerone, G.T.

Kvichak sockeye salmon, once the largest sockeye stock in the world (up to 50% of world’s sockeye production),
declined 73% during brood years 1991-1999 compared with previous years. This investigation examined factors associated
with the decline and implication for salmon management.
Parent escapement and return by age (brood tables) and smolt data were obtained from databases initially developed by D.E. Rogers,
University of Washington. Catch and return data were collected by the Bureau of Commercial Fisheries, Fisheries Research Institute
(FRI), and Alaska Department of Fish and Game (ADFG). These databases were updated in recent years using statistics provided by
L. Fair, ADFG, and statistics in annual ADFG smolt reports (Crawford 2001). The brood table statistics used in this investigation
include catches from Bristol Bay districts only (“inshore returns”). Salmon catches that occurred in Area M fisheries
and in high seas fisheries (mostly prior to mid-1970s) were not included because they are subjected to greater allocation error between
salmon regions and among Bristol Bay stocks. Total return estimates reported by ADFG include all sockeye salmon captured in the False
Pass, Unimak Island, and Shumagin Island areas even though other stocks of salmon are known to mix in these fisheries (D. Eggers, ADFG,
pers. comm.). Ultimately, use of the inshore versus total return brood table probably had little or no effect on qualitative conclusions
about Bristol Bay salmon population dynamics drawn from brood table data.
Recently reconstructed escapement and brood table data for the Alagnak River stock were provided by D. Eggers, ADFG, and obtained from
Clark (2005). This reconstruction led to significant changes in the Alagnak brood table compared with the previous table maintained by
ADFG. A greater proportion of the Naknek-Kvichak District catch was assigned to Alagnak. Re-allocation of Naknek-Kvichak catch had a
negligible effect on Kvichak brood table statistics.
These datasets were archived as part of the North Pacific Research Board legacy project recovery effort undertaken by Axiom Data Science and NPRB in 2025. The goal of the recovery effort was to assess the NPRB-funded data projects from 2002 to 2014 and archive final data packages that were ready for publication to increase long-term accessibility and discoverability. Data packages were archived as is given limited funding and resources.