Seafood Watch

More documents

Recommendations

Info

Seafood Watch® Wild Pacific Salmon Report October 8, 2010 Overall, pink salmon landings in Alaska indicate the stock is in good health. Despite record landings, the main concern revolves around the long-term effects of hatchery supplementation, particularly in Prince William Sound. As Figure 2.6 indicates, returns of wild pink salmon in Prince William Sound have fallen over the past twenty years, while returns of hatchery pink salmon have increased. This disparity has led at least one set of analysts to conclude that Prince William Sound pink salmon hatcheries are replacing rather than augmenting wild pink salmon production in the region, with the likely causes of replacement being “a decline in wild escapement associated with harvesting hatchery stocks and biological impacts of the hatchery fish on wild fish” (Hilborn and Eggers 2000). A more recent summary of research has suggested that wild pink salmon decreases in the Sound have been primarily caused by biophysical variables (Heard 2003). The authors note that pink salmon hatcheries in the Prince William Sound create a net gain of pink salmon up to 25 million fish, though “under certain worst-case scenarios there might be up to a 4.5 million annual wild stock yield loss due to hatchery releases” (Heard 2003). In summary, hatchery operations in Prince William Sound appear to be depressing escapement of wild pink salmon, though the significance of this decrease (e.g., relative to direct fishery impacts on other stocks) remains unclear. Despite the decline, projected wild pink salmon escapement in Prince William Sound in 2004 is 4.6 million fish, above the sustainable escapement goal range of 1.3-2.8 million fish (Plotnick and Eggers 2004). Figure 2.6. Returns and survival of hatchery and wild pink salmon in Prince William Sound (Willette et al. 2001). 45
Seafood Watch® Wild Pacific Salmon Report October 8, 2010 Alaskan Sockeye Salmon After pink salmon, sockeye salmon is the largest contributor to Alaska’s salmon harvest. As with pink salmon, Alaskan commercial sockeye landings have followed a generally upward trend since 1950 (Figure 2.7). Productivity of Alaskan sockeye salmon stocks has generally increased over the past thirty years, particularly following 1973. Increases in productivity have not been uniform across the state. Rather, there has been variation between different runs, reflecting the diversity of mechanisms through which environmental conditions influence the productivity of individual stocks (Peterman et al. 2003). In particular, Hilborn, Quinn et al. (2003) document how the genetic diversity embedded in the hundreds of distinct populations of sockeye in the Bristol Bay area allowed the stock complex to successfully adapt to changing environmental conditions. Alaskan Commercial Sockeye Landings (1950-2002) metric tons 180,000.00 160,000.00 140,000.00 120,000.00 100,000.00 80,000.00 60,000.00 40,000.00 20,000.00 0.00 1940 1950 1960 1970 1980 1990 2000 2010 Alaska 6 year moving average Figure 2.7. Commercial landings of Alaskan sockeye salmon (NMFS 2004b). The largest harvest of sockeye salmon in the U.S. occurs in the Bristol Bay area of southwestern Alaska where 10 million to more than 30 million sockeye are caught each year during a short, intensive fishery lasting only a few weeks. The Bristol Bay sockeye fishery has been described in the fisheries literature as a “classic example” of a sustainable fishery (Hilborn et al. 2003). In 2003, fishermen in Bristol Bay landed 15 million fish, roughly half of the state’s total. These landings reflected the seventh smallest run of sockeye in Bristol Bay in the past twenty years. Harvests of 3-4 million fish each were also reported for Kodiak Island, Cook Inlet, and Prince William Sound. 16 Year 2003 runs in Prince William Sound were average, while Cook Inlet and Kodiak Island reported runs that generally exceeded escapement goals. The projection for 2004 landings of sockeye salmon is up over 50% from 2003 (Plotnick and Eggers 2004). Overall, sockeye salmon appear to be managed around their maximum sustainable yield. In anecdotal support of this, reduced fishing pressure following the 1989 Exxon Valdez oil spill in 16 In contrast, sockeye stocks just south of Alaska have fared poorly. The Canadian government has been petitioned to list sockeye salmon in British Columbia as an endangered species (McRae and Pearse 2004). 46
Page 1 and 2: Seafood Watch Seafood Report Pacifi
Page 3 and 4: Seafood Watch® Wild Pacific Salmon
Page 45: Seafood Watch® Wild Pacific Salmon
Page 97 and 98:
Seafood Watch® Wild Pacific Salmon
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
show all

Seafood Watch

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?