By Adrienne Moore

SAN JOAQUIN RIVER (CBS13) — A fisherman spotted a rare sea turtle on the San Joaquin River that experts say is very far from home.

Angler Dan Maloon posted video in search of affirmation that his freshwater find and eyes weren’t deceiving him.

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“When I first saw it, I thought it was a plastic bag,” he said.

Validation came from the experts at the Turtle Island Restoration Network in Marin County.

“There is no doubt in my mind that this is the Eastern Pacific Green Sea Turtle,” said spokesman Todd Steiner.

He says there are only a few thousand of them left in the world, and they primarily live in the warmer, more tropical waters off of central and southern Mexico.

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“This animal clearly came from the Pacific Ocean, there’s no question about that,” he said. “Apparently went north into San Francisco Bay and now it seems to be heading directly east.”

Steiner says it either became confused and mistakenly swam north, or something else.

“It may be associated with an El Nino event, but even with an El Nino event, it’s highly unusual,” he said.

The wild discovery also leads to increasing concern for the endangered animal. Our cold waters could lead to what’s called “cold stunned.”

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“If it gets too cold, it basically becomes hypothermic and can no longer function,” he said.

Adrienne Moore