SAN FRANCISCO (KCBS) – A river otter dubbed Sutro Sam has been spotted splashing in a pool at the ruins of the Sutro Baths at Lands End, a marine mammal not seen in San Francisco since at least the early 1960s.

Birdwatchers first noticed Sutro Sam back in September feeding on the overgrown goldfish residents have dumped into the pond over the years.

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River otters have also been seen recently in coastal waterways along the Marin Headlands, and people at the River Otter Ecology Project tell the San Francisco Chronicle they suspect Sutro Sam undertook a long swim across the Golden Gate.

There have also been reports of a river otter near Baker Beach which they suspect is the same animal.

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The furry marine mammals, which feed on birds, mussels and fish, were once common throughout Northern California until they were aggressively hunted in the 19th century to feed a market for water repellant coats.

Wildlife experts noted that Sutro Sam is eating well and should not be fed. And although he is not afraid of humans, they said it’s a bad idea to let dogs and other pets get too close.

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