Graham Young, University of Washington, School of Aquatic and Fishery Sciences
Mary Arkoosh, NOAA, Northwest Fisheries Science Center
John Dentler, Troutlodge Sablefish LLC
Walton Dickoff, NOAA, Northwest Fisheries Science Center
Joseph Dietrich, NOAA, Northwest Fisheries Science Center
William Fairgrieve, NOAA, Northwest Fisheries Science Center
Rick Goetz, NOAA, Northwest Fisheries Science Center
Kurt Grinnell, Jamestown S’Klallam Tribe
Laura Hoberecht, NOAA, National Marine Fisheries Service
Adam Luckenbach, NOAA, Northwest Fisheries Science Center
Jim Parsons, Troutlodge Sablefish LLC
Pacific sablefish, with their firm flesh and buttery flavor, are an exceptionally valuable food fish. But wild harvests are limited, and bottlenecks in larval production have discouraged sablefish aquaculture. This project removed these barriers by using newly developed technologies to produce all-female (hence faster-growing) larvae on a commercial scale, to wean them faster from costly live food to industrial feed, and to rear them at optimal temperatures for growth. It also explored new techniques to induce ovulation, improved fertilization success, and vaccinated larvae by immersion rather than giving expensive injections at the fry stage.
With declining wild stock, a U.S. market value of over $100 million annually and an ability to grow quickly, sablefish have great potential for commercial aquaculture. However, steep hurdles such as poor-quality eggs and larvae, lengthy production processes and disease have stymied efforts to produce sablefish at commercial scale.
Washington Sea Grant researchers investigated potential solutions to the obstacles that prevent sablefish from becoming commercially viable. They developed and tested new protocols for producing better eggs and increasing larval production. In an effort to speed growth rates, they selected only females for rearing, reared the larvae at warmer temperatures, and investigated the use of DMSP, a chemical produced by plankton, the larvae’s favorite food. To reduce feeding costs, they substituted clay for expensive plankton. They also developed new technologies for protecting juveniles against disease.
After conducting a series of tests, several innovations succeeded in producing commercial-scale quantities. By adopting a strategy to produce all-female progeny, the time to market was shortened. The team also perfected an egg holding strategy that allows more time for egg collection without compromising quality. The researchers reared larvae at warmer temperatures to speed growth rates, reduced rearing costs by substituting clay for expensive algal additives to larval tanks, and successfully applied an injection vaccine to juvenile sablefish to protect against Aeromonas salmonicida, a common disease. The project benefited the local fishing community by employing Westport purse-seiners and a local processor, Ocean Gold Seafoods, to harvest and process the initial product – more than 8,000 fish weighing more than 40,000 pounds. Research results are to be applied in a pilot project to develop procedures for growing out sablefish on a commercial scale.