Mysterious shark washes up on Salmon River beach near Riggins

Do Riggins people who raft and fish near Riggins need a bigger boat?

Well, the Salmon River is home to some nonnative predatory fish, but fear not, sharks are not among them.

That’s according to Joe DuPont, regional fisheries manager for the Idaho Department of Fish and Game at Lewiston. The agency's phones lit up Monday with reports of a shark that apparently washed up on a beach near Riggins. Agency personnel dispatched to investigate determined the reports to be accurate — at least in part. They did indeed find a dead and aptly named salmon shark.

But DuPont said it's highly unlikely the out-of-place fish got to Idaho on its own or that there are more out there.

“They can’t live in freshwater,” he said. “That would be like finding a sailfish up here and wondering, ‘Could they really be up here?’”

Instead he suspects a prankster left the shark hoping for just the sort of reaction that occurred Monday and is likely to occur from the ensuing media reports.

Salmon sharks are native to the cool waters of the north Pacific Ocean but they do venture as far south as southern Baja, California, Mexico, according to the Alaska Department of Fish and Game’s website. As their name suggests, they do eat salmon. According to Alaska Fish and Game, they also feed on sablefish, squid, herring, other saltwater fish, and sometimes sea otters and sea birds. At times they can put a dent in salmon returns. In 1998, salmon sharks ate 12% to 25% of the salmon returning to Prince William Sound, according to Alaska Fish And Game.

They can reach lengths up to 10 feet and weigh more than 600 pounds but are more commonly 6 to 8 feet long.

There are some sharks that can survive for prolonged periods of time in freshwater. Bull sharks, for example, have been found in the Mississippi and Amazon rivers.

The carcass of the mysterious Salmon River salmon shark was taken to Rapid River Hatchery and is being stored in a freezer there. DuPont said there are no immediate plans for a necropsy, but the carcass is being preserved.

Barker may be contacted at ebarker@lmtribune.com or at (208) 848-2273. Follow him on Twitter @ezebarker.