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Managing for Resilience:

Case Study: Bristol Bay, Alaska

Tom Quinn, Ray Hilborn, Daniel Schindler and Don Rogers
School of Aquatic and Fisheries Sciences
University of Washington 

The sockeye salmon populations of Bristol Bay, Alaska have been fished commercially for over a century, and are among the best examples of sustainable fisheries. The purpose of this presentation is to show how the geography of the region provides a fundamental template that organizes the population structure of the salmon, the human communities, the fisheries, and their management. The geography is based on watersheds containing the large lakes where juvenile sockeye salmon rear prior to seaward migration. The watersheds have been structured into five fishing districts, with sub-districts in some cases. The fishing is conducted by gillnet vessels that can move among districts, by set netters who fish for migrating salmon at fixed marine locations, and by subsistence fisheries at fixed locations near spawning grounds. These fisheries vary in the cost to enter, mobility, extent of local involvement, and tendency to exploit mixed or single populations. In parallel with the fisheries, the genetic structure of the salmon populations is primarily based on the watershed scale, with additional structure provided by lakes within the watershed, types of breeding habitats, and finally the specific breeding sites. The life history patterns of the salmon also vary consistently among the watersheds, habitat types, and breeding sites in ways that reflect the productivity of the lakes and the physical attributes of the spawning areas. Finally, the abundance and productivity of sockeye salmon have varied over these same set of spatial scales during the past century. However, productivity has not been uniform over time in the districts, watersheds within districts, habitat types within watersheds, and spawning sites within habitat types. Consequently, the system as a whole has been more stable than any component, at any of these scales of organization, reflecting the fundamental role of biocomplexity in the overall resilience of the species in the region.

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