Salmon Shark

The Salmon Shark occurs in the eastern and western North Pacific and its population appears to be stable and at relatively high levels of abundance. Currently there is no directed fishery in the Northeast Pacific, apart from a small sport fishery for the species in Alaska. Bycatch in the Northeast and Eastern Central Pacific appears to be at low levels and is not increasing at this point-in-time. Additionally, with the current ban on commercial fishing in Alaska state waters and fairly conservative sport fishing limits, it appears that the population is stable. By catch in the Eastern and Western Central Pacific has been significantly reduced since the elimination of the drift gillnet fishery and the population appears to have rebounded to its former levels. In addition, the most recent demographic analysis supports the contention that salmon shark populations in the Northeast and Northwest Pacific are stable at this time and it is assessed as Least Concern. After spending the summer in the northern part of their range, the salmon shark migrates south to breed. In the western North Pacific they migrate to Japanese waters whereas in the eastern North Pacific, the salmon shark breeds off the coast of Oregon and California. Males mature at 5 years of age and females at 8-10 years. Salmon sharks breed in late summer to early autumn. The internal developmental period in salmon sharks last 9 months. Developing embryos will consume unfertilized eggs in the womb. The female give birth to live young. Once the sharks are born, they are completely independent, and they have to fend for themselves As an apex predator, the salmon shark feeds on salmon, squid, sablefish, herring, walleye pollock, and a variety of other fish. They have been seen taking other prey including sea otters and marine birds. In 1998, Alaskan salmon sharks consumed twelve to twenty-five percent of the total annual run of Pacific salmon in Prince William Sound. Salmon sharks are highly migratory, with segregation by size and sex, and with larger sharks ranging more northerly than young. Migration for the salmon shark is ultimately dependent on the concentration of the available prey species. Adult salmon sharks migrate alone or in loose groups of 30 to 40 individuals, following schools of Pacific salmon — including Sockeye (Oncorhynchus nerka), Pink (Oncorhynchus gorbusha), Chum (Oncorhynchus keta), and Coho (Oncorhynchus kisutch) — as they swim along the great arcs of current flowing off the coasts of northern Japan and the Kamchatka peninsula, the Aleutian Island chain, Alaska and British Columbia. There is an annual north-south movement of salmon sharks in both the eastern and western Pacific. Many salmon sharks feed in the coastal waters of the Gulf of Alaska, in particular Prince William Sound, home to Pacific salmon spawning grounds. Some of these sharks rapidly migrate southeast towards the west coast of Canada and the US; however, some remain in Prince William Sound and the Gulf of Alaska during winter months despite the colder temperatures.
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Category:Fish
Category:Sharks
Category:Alaskan Animals
Category:Wildlife