Just because the City doesn’t have a lot of information about San Francisco coyotes doesn’t mean that the information doesn’t exist. I myself have been observing and documenting coyote behavior in San Francisco over the last 9 years.* I am rewriting this posting from questions I received on the Stern Grove Dog Owners’ Group site, where there has been a lot of questioning and apprehension by dog owners about our coexistence policy and about a general lack of information regarding San Francisco coyotes. I hope it answers some basic questions.
POPULATION NUMBERS: Based on my observations, I would say that coyotes in San Francisco number in the dozens, not in the 100s. Their numbers here and elsewhere are limited by their territoriality: they exclude outsider coyotes from their territories, and their territories must be big enough to support them and their families — this has been estimated to be about a square mile per coyote, or 2 to 4 square miles per family as noted by Professor Stan Gehrt in Chicago, and coyote families fluctuate between 2 and 5 coyotes. Even if they needed 1/2 this amount of space, you can see that SF’s 49 square miles isn’t going to become overrun with coyotes.
POPULATION GROWTH. Within their established family territories, which include nearly all the parks, coyote numbers have not been increasing over the last six or so years. Rather, the number of coyotes has been fluctuating from about 2 to 5 and then back down again — it depends on what is happening interpersonally within the one resident family which lives in that claimed and exclusive territory — most parks or golf-courses have only one family with family-size in continual flux but stable over time. This is what I’ve observed.
And I don’t think there’s a sudden population “explosion” going on right now in San Francisco. This year I’ve seen small, including one-pup, litters. The drought might be playing a role in the low survival of pups. And also remember that under normal circumstances, survival rates for coyote pups within their first year of life is only around 30%.
The coyotes’ chief “predator” in the city is cars. There have been lots of coyote deaths-by-cars in San Francisco. I’ve seen or been told about them on Mansell Street (off of McLaren), on Portola, on O’Shaughnessey, on Sloat by the zoo, on Marview below Twin Peaks, on Lake Merced Avenue, etc. Professor Stan Gehrt in Chicago thinks cars are what kills most urban coyotes. Besides cars, malnutrition and disease end lives in the city, as in rural areas. But in rural areas thousands lose their lives through brutal hunting and shooting. The city is actually a sanctuary for them, but even in a city few coyotes live out their full potential life-span.
DISPERSAL. I’ve observed that coyotes disperse throughout the year, depending on interpersonal family dynamics and resources: I myself have never noticed a set “dispersal season”, and at this early autumn time of year, when coyote pups are only 6 months old, it would be too early for them to disperse anyway. I’m troubled by claims from the city about a “dispersal season” being the reason for more sightings right now. Coyote specialists I’ve spoken to, including Jon Way, corroborate my own observations that coyotes disperse throughout the year. I hope we can clear up the misinformation out there.
The “extra” coyotes, in time, will move out of the city or fill vacant niches: they appear to have their own built-in GPS systems, like migrating birds — coyotes who are relocated can find their way back, and those who leave on purpose can find their way out of the city. For those who don’t leave the city, vacant niches might be found in smaller parks, and maybe even in areas in some neighborhoods: you can prevent the latter by creating disturbances, and by eliminating the foods that attract them, whether it is dog food, raccoons, skunks, rats or even free roaming cats. Rather than move into neighborhoods, they are more likely simply to trek through, doing their job of balancing the environment by eliminating excess rats and other rodents, most of which they do when it’s dark outside. Remember that their territories must be big enough to support them, and their territorial boundaries do not overlap: if there are a number of sightings in an area, it will likely be the same coyotes over and over again which are being seen.
Always and everywhere, the main issue with coyotes is pets. So keep small pets out of harm’s way by supervising them and not allowing them to roam free. Keep larger pets leashed when you see a coyote — coyotes and dogs do not get along. Please watch the online video “Coyotes As Neighbors”, which can be Googled, and look for additional pertinent coyote guidelines at CoyoteCoexistence.com.