Distinct population segments in Puget Sound rockfishes (Sebastes spp): improving management of a vulnerable species complex

Washington Department of Fish and Wildlife marine groundfish managers are responsible for managing rockfish in the Puget Sound region, but lack up-to-date information on the population structure of most rockfish species. A Washington Sea Grant (WSG)-funded research team generated state-of-the art genetic data to provide species-specific information for management of this vulnerable species complex. They gathered data from ~10,000 genetic markers in eight species of Puget Sound rockfishes and mapped population boundaries based on their genetic markers. Research revealed that population structure was different for each species and improved understanding over previous assumptions. The updated data will help shape management strategies for marine managers in Washington and the tool may be broadly applied to other fisheries.

Project background

Rockfishes are an important component of the ecosystems of Puget Sound and the Salish Sea. Due to stringent management following overfishing, most species have recovered along the coast, but not within Puget Sound. The connectivity between populations in the two areas is a central question of managers, as rebuilding plans for Puget Sound rockfishes depend to a large extent on the level of spillover from the coast. In fact, the lack of clear scientific information on connectivity between Puget Sound and the coast complicates justification of the current ban to retain incidental rockfish catches in the recreational salmon fishery. The project provides information to allow a sustainable recreational fishery on rockfish species that are replenished by spillover from recovered coastal populations. The overall goal of the proposed project is to provide a comprehensive survey of population connectivity in 12 rockfish species.

Results and findings

Findings suggest that some Puget Sound rockfishes are hybridizing, complicating management by population group. Preliminary results show that 1) genetic structure in two Puget Sound species is indeed affected by hybridizations and those species are not good examples to infer population structure in non-hybridizing species; 2) hybrids are localized with Puget Sound, suggesting limited dispersal between Puget Sound and the coast. These results provide the basis to explore the feasibility of targeted rockfish fishing in Puget Sound.

Contact information

Lorenz Hauser
Professor
School of Aquatic and Fishery Sciences, University of Washington
206.685.3270
lhauser@uw.edu