Coyote Swam Miles to Alcatraz, Scientists Stunned
- National Park Service researchers said the coyote spotted on Alcatraz in January likely swam there from Angel Island, not San Francisco, after DNA testing. - Scat collected after a Jan. 24 sighting matched Angel Island’s coyote population, pushing the swim estimate to about 2 miles across cold, choppy bay water. - That makes the trip rarer and harder than first thought — and sharper for wildlife managers protecting Alcatraz’s nesting seabirds.
A coyote reaching Alcatraz was already weird. The new part is what made biologists do a double take. They first assumed the animal came from San Francisco — a little over a mile away. But DNA work now points to Angel Island, which means the swim was roughly 2 miles through cold, fast, messy bay water. ### What changed this week? The big update came on May 4, when the National Park Service said DNA from scat found on Alcatraz matched the coyote to the Angel Island population. That overturned the earlier guess that he had paddled over from San Francisco. The coyote was first documented after a Jan. 24 visitor sighting and photo, then tracked through fresh prints and scat. ### Why does Angel Island matter so much? Because it turns an already impressive stunt into a much harder one. San Francisco to Alcatraz is a bit over 1 mile. Angel Island to Alcatraz is about 2 miles. In open ocean that difference is one thing. In San Francisco Bay — with chop, currents, cold water, and a rocky landing — it is a very different level of effort. ### How did they figure out where he came from? Park staff did the unglamorous fieldwork first. After the sighting, they searched for tracks, installed trail cameras and audio recorders, and collected scat. That sample went to UC Davis’s Veterinary Genetics Laboratory, where researchers identified the animal as a male and matched him to coyotes previously sampled on Angel Island. Basically, the mystery got solved with poop and a genetics database. ### Was this coyote trapped on Alcatraz? Maybe not — and that is part of why the story stays strange. Park staff kept monitoring the island for months, but they never saw him again, never caught him on the cameras or audio gear, and found no remains. Their best public answer right now is simple: they do not know what happened next. He may have left the same way he arrived. ### Why were officials worried at all? Alcatraz is not just a tourist site and old prison. It is also seabird habitat. That matters because a coyote on a small island can become a serious predator problem fast, especially during nesting season. Park staff were prepared to capture and relocate the animal to more suitable habitat within the Golden Gate National Recreation Area if they found him. ### Do coyotes actually do this? Coyotes can swim, yes. But this specific trip seems unusually extreme. Wildlife experts quoted in coverage said they had not heard of another coyote making a journey this long through such difficult currents. The likely reason for the move is familiar coyote behavior — dispersal. Young or roaming coyotes often go looking for territory or a mate, and sometimes that means trying routes that look absurd to humans. ### So what is the real takeaway? Urban wildlife is more capable than people think. That is the wonder part. The management part is trickier — animals can reach places managers assumed were naturally protected. This coyote did not just visit a famous island prison. He exposed a gap in how people think about barriers in a living bay. The surprise is no longer that a coyote got to Alcatraz. It is that he probably came from farther away, by a harder route, and may have made it back out again.
