Fish & Water - Sounds Wild
Shark Travels

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Shark Travels

A shark fin cuts the cold water of the Bering sea as a four-foot-long salmon shark cruises near Saint Lawrence Island. There's something unusual about that tall dorsal fin, and a closer look reveals a cigar-size device fastened to the side of the fin, with a short antennae pointing skyward. It's a tracking device. Fish and Game researchers studying juvenile salmon in the Bering Sea have equipped several male salmon sharks, caught incidentally in salmon trawl nets, with tracking devices to learn more about how their movement patterns relate to season and prey availability.

Sleeper sharks are northern sharks that cope with near-freezing water by having a slow metabolism. Salmon sharks take a more mammalian approach - they are warm-blooded fish and can maintain their internal body temperature as much as 21°C above the ambient water temperature. This ability to hunt and thrive in cold water means salmon sharks may be one of the most northern dwelling sharks in the world. They have even been caught above the Arctic Circle.

Like most sharks, Salmon sharks segregate by sex. Biologists are learning that Female salmon sharks dominate the eastern North Pacific and Prince William Sound, while males dominate the western North Pacific and the Bering Sea. Tagged male sharks like this one are providing a unique opportunity to learn about their movements and behavior.