A coyote has amazed onlookers by swimming to Alcatraz Island, navigating the treacherous waters of San Francisco Bay in what may be the first recorded instance of the species reaching the former prison island by water.

The animal, thought to have come from San Francisco or nearby islands, was captured on video by a tourist and shared by Aidan Moore of Alcatraz City Cruises. Clips show the coyote doggy-paddling determinedly toward Alcatraz, eventually reaching the rocky shore shivering and bedraggled. Moore reported the sighting to National Park Service rangers, but the coyote disappeared before officials could locate it.

Experts suggest the coyote may have been seeking new territory amid pressure from other local animals. Janet Kessler, a naturalist studying San Francisco coyotes for 20 years, said the journey would have been exhausting but survivable, as the island offers small prey and water resources. Alcatraz, once a maximum-security prison, closed in 1963 and is now a museum attracting more than 1 million visitors annually.