After nearly 100 years, coyotes are back in San Francisco

If a person rides a bicycle on the same road for 20 years, he will definitely notice changes. Such was the case in San Francisco, where the fall meeting of the American Geophysical Union was held last week, as it has been for several years.

Some observations:

1. After this option was taken away in 2020, people were really excited to be together again.

2. San Francisco has more bike lanes than the last time I rode in 2019. For example, the main thoroughfare through Golden Gate Park, John F. Kennedy Boulevard, is now mostly closed to cars but open to pedestrians and bicycles.

3. Since my bosses at the Institute of Geophysics started paying for me to attend this conference in 1999, coyotes seem to be populating San Francisco again.

Third example: My cousin Heather Liston promised me to see coyotes while taking me through the San Francisco Presidio, a former U.S. Army base adjacent to the Golden Gate Bridge that occupies Over 2 square miles of prime location.

As we were hiking one of the many trails in the Presidio, a coyote appeared, very close. It is wary but accustomed to being near human activity, crunching the remains of feathered things. Heather took some nice photos of the coyote before it disappeared into the brush.

As I rode my bike around San Francisco to and from the conference the rest of the sunny week, I saw three more coyotes, each in the park.

One night as I was passing through a darker area of ​​Golden Gate Park using my Alaskan bike lights, I thought I heard a siren, but something was wrong with the sound.

I braked to a stop. The eerie howls and calls of coyotes cut through the night as my feet hit the asphalt. It sounds like 10, but it’s probably not that many.

The coyote’s recent takeover of one of America’s most densely populated cities likely began around 2003. At the time, a team led by Benjamin Sacks of the University of California, Davis, extracted DNA from the blood of a male coyote captured in the Presidio and later returned there.

Sachs discovered that the coyote was related to many coyotes that live in Marin County and elsewhere north of San Francisco. This led him to deduce that the animal at some point trotted across the 1.7-mile-long Golden Gate Bridge, which has trails on both sides of U.S. Highway 101.

“Our findings reflect an example where human modification of the landscape may…facilitate gene flow between historically different parts of a species’ range,” Sachs wrote in a paper.

Biologists now estimate the San Francisco coyote population at about 100. The last individual was reported in Golden Gate Park in 1925, and about a century later they reoccupied the peninsula.

In a 2023 paper on the modern coexistence of coyotes and humans in San Francisco, Christine Wilkinson noted that although coyotes are native to San Francisco, they have become increasingly widespread due to poisoning, hunting, and urban expansion. It disappeared then.

As for Alaska, biologists believe coyotes arrived here about a century ago. In his 2016 book Coyote America, author Dan Flores proposed that people helped coyotes expand from their core population in the western United States all the way to El Salvador (possibly following domestic sheep herds) , all the way to Alaska (utilizing gold fragments from miners and others who flooded the area).

[The secret lives of animals are playing out all around us in Alaska]

In San Francisco, reports of coyote conflicts have increased significantly over the past five years, Wilkinson wrote. But many city residents have also expressed a desire to coexist with coyotes.

The latter seemed to be the attitude of my cousin, and of the mother with the baby strapped to her chest as she and I watched two coyotes trotting on the park lawn one night.

Coyotes are now protected in San Francisco. It seems they will roam the city as long as there is a quiet place to raise their young and urban food sources such as wild mice and many other things.

Since the big conference I’ve been in San Francisco for last December will be in Washington, D.C. next year, who knows if we’ll be traveling this way again? I want to thank my cousin Heather and my friend John Arnz for hosting me on his couch many nights in San Francisco. Thanks to the three directors of geophysical institutes who have guided me towards the December sunshine over the years.