Wildlife experts caution travelers after otter attacks swimmer in Placer County lake

SAN FRANCISCO (KGO) -- If you're going to the Sierra, take note. Wildlife experts are reviewing reports of people being bitten by otters.

"It is by far the most terrifying experience I have ever had in my life," said Matt Leffers, describing an attack last month while swimming at Serene Lakes in Placer County.

Leffers was bitten at least a dozen times by two otters. He suffered close to 40 puncture wounds.

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Wildlife experts warn otters may be more aggressive around their hunting grounds. But they say attacks are rare.

"They won't normally attack people or larger animals. However, they will defend their territory if they feel threatened," said Peter Tira from the California Department of Fish and Wildlife.

Otters may be expanding their hunting grounds because of an abundance of fish. Fish and Wildlife is asking residents of Serene Lakes to limit fish stocking in the lake.

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