Available at http://depts.washington.edu/uwconf/2005psgb/2005proceedings/index.html
Rockfish comprise at least 28 of the over 200 species of fish within the Salish Sea. Because of their unique life-history, past over-exploitation, and currently degraded habitats, populations of many rockfish species in the Salish Sea have declined and some have been listed as Species of Concern by the State of Washington under the U.S. Federal Endangered Species Act and the Canadian Species at Risk Act.
The Salish Sea comprises over 6,900 square miles of habitat used by rockfish and is managed under the various jurisdictions of the Government of Canada, the United States, and the State of Washington. This workshop convened scientists, managers, and industry professionals to focus on recent and on-going research and recovery efforts of rockfish and their habitats in the Salish Sea to enable further collaboration.
The first day of the workshop included sessions detailing recent research on the historical context of rockfish depletion, benthic habitat surveys and abundance estimates, stressors, ecosystem and species interactions, juvenile recruitment, and genetics.
The second day of the workshop focused on agency, tribal, and Canadian perspectives on rockfish recovery, and included concurrent sessions designed to list additional research priorities related to reserves and population biology.
A final plenary session focused on collaborative planning and additional research needs.
A survey was distributed at the end of the workshop regarding the regional recovery priorities and the relative amount of research needed to implement each measure.
Past rockfish workshops and symposiums have focused on the establishment of reserves (Yoklavich 1998), population biology, assessments, and management (Heifetz et al. 2005), and conservation of ecological genetics and stock structure (Berntson et al. 2007) along the North Pacific.
This workshop specifically focused on rockfish in the Salish Sea because of its unique and diverse habitats, and its complex socioeconomic dynamics that influence rockfish research and recovery measures.
Recovery of severely declining resource stocks often leads to enforced quotas or reduced human access to those resources. Predators, however, do not recognize such restrictions and may be attracted to areas of increased prey abundances where human extraction is being limited. Such targeting by predators may reduce or retard the potential recovery of depressed stocks. In the San Juan Islands, northern Puget Sound, USA, marine reserves were implemented to recover depressed fish populations. We examine the role of harbor seals Phoca vitulina in the San Juan Islands food web. We describe the temporal and spatial variability in their diet, emphasizing species for which reserves were established (rockfish Sebastes spp.) and other important depressed stocks, including salmon Oncorhynchus spp. and Pacific herring Clupea pallasii. During winter and spring, seals primarily consumed Pacific herring, Pacific sand lance Ammodytes hexapterus, northern anchovy Engraulis mordax, and walleye pollock Theragra chalcogramma. During summer/fall, adult salmonids composed >50% of the diet and were particularly important in odd-numbered calendar years, when pink salmon O. gorbuscha spawn. Rockfish were not a primary prey species at any time of the year, suggesting that the abundance of alternative prey species may reduce predation pressure and provide a critical buffer to rockfish predation. The importance of considering increased visitation by marine predators to areas where potential prey are enhanced through restrictions on human extractions should be considered when modeling the efficacy of quotas and reduced access areas, such as marine reserves.