CNN says: Otters winning battle of wits.

In an admission that the slick-furred creatures refuse to respect boundaries imposed by man, authorities want to officially abandon their otter-relocation policy.
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Fearful that an oil spill could wipe out otters elsewhere, the agency tried to create a reserve for 150 otters on San Nicholas Island, about 80 miles south of Santa Barbara.

Biologists had thought the otters would stay near San Nicholas, which has plenty of food and is surrounded by deep water that is hard to swim across. Even if the otters wanted to leave, it seemed improbable that they had the navigation skills to do it — especially since they were taken to the island by plane.

“We flew ’em out there,” Sanders said, “although we didn’t blindfold them.”

I always knew otters were smart :o)