A Detailed Look at SF Coyote Diets and Some of the Causes for Individual and Family Differences

For full article, press here: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.70152

Abstract

In the past decade, studies have demonstrated that urban and nonurban wildlife populations exhibit differences in foraging behavior and diet. However, little is known about how environmental heterogeneity shapes dietary variation of organisms within cities. We examined the vertebrate prey components of diets of coyotes (Canis latrans) in San Francisco to quantify territory- and individual-level dietary differences and determine how within-city variation in land cover and land use affects coyote diet. We genotyped fecal samples for individual coyote identification and used DNA metabarcoding to quantify diet composition and individual niche differentiation. The highest contributor to coyote diet overall was anthropogenic food followed by small mammals. The most frequently detected species were domestic chicken, pocket gopher (Thomomys bottae), domestic pig, and raccoon (Procyon lotor). Diet composition varied significantly across territories and among individuals, with territories explaining most of the variation. Within territories (i.e., family groups), the amount of dietary variation attributed to among-individual differences increased with green space and decreased with impervious surface cover. The quantity of anthropogenic food in scats also was positively correlated with impervious surface cover, suggesting that coyotes consumed more human food in more urbanized territories. The quantity of invasive, human-commensal rodents in the diet was positively correlated with the number of food services in a territory. Overall, our results revealed substantial intraspecific variation in coyote diet associated with urban landscape heterogeneity and point to a diversifying effect of urbanization on population diet.

INTRODUCTION

Urban landscapes are complex mosaics of biophysical properties that have been designed to support diverse human activities and requirements (Des Roches et al., 2020). Within cities, transitions in percent cover of impervious surfaces, building density, economic activity, and . . .

For full article, press here: https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.70152

Misrepresenting *Incidents*

Video posted on NextDoor (see below) taken by a bystander who claims the coyotes in this video followed and then cornered a dog and walker . The video repeats several times, giving you an opportunity to see what happens.

Reports of dog/coyote incidents this year seemed to be up, including three small dogs killed at Crissy Field by a coyote. But are there more such incidents? Whether there are or not, all could have been prevented had there been fuller education and effective signage.

Take Crissy Field. Coyotes have appeared on Crissy Field regularly for many years. Lack of adequate signage, along with only a few reported coyote sightings during doggie play time, probably contributed to folks feeling that, since it was a designated *off leash* area, it was safe for their little dogs. But an *off leash* area means nothing more than that dog-owners are not going to be ticketed here for having their dogs off-leash. It does not imply that the area is free of coyotes nor necessarily safe for little dogs. Even in off-leash areas, an owner must always stay vigilant and constantly supervise their pets for many reasons: including danger from larger dogs an yes, coyotes — and children notoriously get nipped by dogs. Coyotes and dogs don’t like each other and don’t get along. Coyotes live throughout the entirety of San Francisco, so small dogs especially should never be left unsupervised wherever they are.

Because of the loss of 3 small dogs to coyotes in Crissy Field, coyotes became a political issue with pressure put on the City to do something about the coyotes. The city bowed to the pressure and went out and shot the coyote culprit, and signs have finally been posted in the area.

For months afterwards, some of the dog owners wanted more done than this. They banned together, vowing to keep the Crissy Field issue alive. They wanted *something done* about the coyotes: they wanted them culled, relocated, neutered — anything to diminish or get rid of them. They claimed that, because of more reported sightings and more reported incidents, that we were being overrun by coyotes. But I haven’t found evidence of this in the territories I keep track of.

When I’ve asked specifically WHERE in the city someone has seen *more* coyotes, they list several different places in the city where they have seen one or several, and then rely on the sightings by other people to support their belief that we are being overrun by coyotes who, to them, have become a problem. I know most of the coyote families and their territories, and I can vouchsafe that there are not more in the seventeen territories I know well: just one family per territory. Yes, sometimes the coyotes become more visible, and there have been regular *hotspots* which they frequent for stretches of time during the long denning season, but this doesn’t equate to an increase in their population. The population for each family/territory is a routinely fluctuating one, expanding during the pupping season and then shrinking back down to the alpha parents with often several yearlings lingering to help with the following year’s pups before moving on. Territories are owned by an alpha breeding pair and their pups and yearlings (yearlings are pups born the previous year) who generally disperse sometime before two years of age. Those who survive cars appear to move south and out of the city because all territories are already taken within the city proper.

As part of the effort to keep the *dangerous coyote* story alive, the incidents of the three dogs killed at Crissy Field were reported in at least four different newspapers. On NextDoor, there have been many postings of simple sightings informing folks to “please watch your pets” — these are valuable notices to people with pets. But these postings inevitably attract doomsday comments and opinions, many of them fear-mongering from people who don’t want coyotes here.

In addition, some mere sightings have been spun into postings of tall tales — on the same level as the runner in Marin who claimed to have been attacked by a coyote which turned out to be fabricated [https://coyoteyipps.com/2022/08/21/attacker-or-attacked/]. Some of the postings about coyotes chasing dogs and their walkers, or coyotes killing dogs, are simply not true, and I now wonder how many of these stories have been *enhanced* or totally made up. Since these are reports I’m seeing on NextDoor, I can image that the same reports are sent to Animal Care and Control (ACC). ACC does not vet what they hear — I know this from personal first-hand experience. So their statistics are not reliable: garbage in = garbage out. [Vetted: critically reviewed and evaluated for official approval or acceptance]

Here is one such posting on NextDoor which attracted a slew of fearful comments and misinformed speculations. Fortunately, as many commentators saw through to the reality. I hope folks are aware of these for what they are.

1. Here is a link to one of the *incidents*, the one associated with the above posted video: [https://nextdoor.com/p/bpt5DR4Pd2Rr?utm_source=share&slp=&share_platform=1&extras=NTM1NzAw]

Martha: Edited • Saw this at 7:40am this morning. They were chasing and trying to corner a man and his 50 lb dog (seen towards end of video in yellow shirt). I walk my 12 lb yorkie after 9am for this reason and avoid walks after sun down. This is not the first time they’ve approached humans here. There’s a daycare 100 ft away, too. Near 18th St and Carolina St., between two apartment buildings. Edit: I was at the gym and noticed the man run across the paseo with his dog first. He looked concerned and was looking over his shoulder. At that point I suspected a coyote would show up and I took out my phone since my neighbors also reported seeing coyotes here. I didn’t expect to see two hunting together. I stopped my workout to go scare the coyotes but by the time I got outside they all were gone. Edit 2: The man did not stumble upon the coyotes. They followed him. I have a newer post that shows from my building’s security footage that they were on his tail.

Take a careful look at the video to see what is actually going on. Here is a fearful commentator and then my reply to her:
Gloria: This is very scary. Coyotes are out of control in San Francisco. These coyotes obviously wanted that man’s dog. My reply: Gloria, “Obviously”? I think you need to look at the video again: the coyotes in fact are obviously AVOIDING the dog. When they see what way the man is going, they go the other way.

2 .Here’s the link to another: [https://nextdoor.com/p/JyWwxSYCFFK8?utm_source=share&slp=&share_platform=1&extras=NTM1NzAw]

Gayle: 10/24 at 1:00am on De Haro & 17th Street someone’s dog was killed by two coyote’s who chased it into a corner and mutilated the poor pup. The sounds were spine chilling. I ran outside with a broom to help but the dog was already dead and being carried away. How is this acceptable? This is a city, not a National Park. I am an animal person all the way, but living with wild animals is NOT OK. We must call the police and complain. There are now 4 dens on Potrero Hill. I see them weekly now.

This is a third person reporting on a supposition or presumption, without checking out the details — and it was posted at least three times. There was a *sound*. No one saw an incident. I myself have heard raccoons emit spine chilling sounds when they are attacked by a coyote. No dog owner has come forth saying their dog was mauled or missing — i.e., this would have been a first person account. Few dogs in fact are out at 1:00 am in the morning, especially running loose, whereas this is prime time for raccoons to be out. So I’m doubting the report and calling it “garbage in” barring further evidence. But it has generated a large number of comments and amplified existing fears.

Botanical Garden Incident of June 30, 2024: In addition to the Crissy Field coyote/dog incients, we’ve had several instances of bad news over the summer concerning the coyotes. In the Botanical Garden at the end of June a coyote bit a small child at a daycamp. The repercussion from the City was to shoot three coyotes from one coyote family indiscriminately. I knew about the den there: I had seen Mom coyote lactating and the rest of the family come out at dusk for their activities. But the City denied there was a den there, and said the bite had been caused by a rare “aggressive coyote”. In fact many people, including the City, knew there was a den there, so my question to them was: Why were not denning signs posted? Why weren’t the camp counselors educated adequately? Precautions could have been taken to prevent such an incident, but were not. Then in the aftermath, we learned that THREE coyotes were shot. Why three, I had to ask. In fact, one of those shot was a three-month old pup: what other proof does the city want that a den was there?, but the City never corrected their misinformation, even though they knew the facts.

Lastly, and impressively, The Chronicle on October 30, 2024 in their article by Nora Mishanec entitled “Reports of S.F. coyote encounters exploded this year. What should the city do about it?” The article was sensationalist and fear provoking more than anything else.

The word *exploded* stands out, and implies a huge increase in both sightings and actual incidents., if not even an *explosion* in their population. The word *explosion* is most often associated with population numbers. Further reading shows there were 600 reports of encounters. C’mon everyone! This is less than two sightings/encounters a day in a population of 90 adult coyotes and a human population of 788K in 2024 and a dog population of over 200K. One has to question the newsworthiness of what the Chronicle writes, except to fan the flames of controversy and raise the level of fear. Here is the article for anyone interested: https://www.sfchronicle.com/sf/article/coyote-encounters-animal-control-19855206.php. There is also a map of the 690 sightings: https://www.sfchronicle.com/projects/2024/coyote-sightings-sf/. I want readers to beware that these sightings have very little to do with the coyotes and their population, and much more to do with the few humans who decide they need to report them: most people don’t report sightings, but people who are afraid have been encouraging everyone, on NextDoor, to report these. Where groups of individuals are pressing folks to report these, of course, there are more reports.

What I’m trying to point out is that coyote sightings, coyotes looking at you, coyotes walking in your same direction across the street or even 30 feet away, should not be *alarming incidents*, and neither should coyotes following or escorting dogs. These things happen regularly and should be expected in an urban environment. Dog owners can keep situations from escalating by keeping their dogs from barking at or lunging at coyotes: these things incite coyotes to react negatively: walking on and away from the coyotes — without running — almost always de-escalates tensions between dogs and coyotes.


Neighbors In The Night, by Vanitha Sankaran at Pacifica Magazine

When asked about the personality of coyotes, Kessler lights up. “Your average coyote is intelligent, curious, playful, protective, adventurous, cunning, independent, self-reliant, has family values and a frontier spirit, and strong individuality. Those are the same rugged frontier characteristics we value in ourselves.”

Writer Vanitha Sankaran from Pacifica Magazine recently contacted me requesting an interview and photos of coyotes for an article she wanted to do. Coyotes were being sighted more frequently in Pacifica, so it was an opportune time to get some information out to the public. I was, of course, happy to do this.

Here is her article, capturing how and why my passion began and grew as I discovered the extent of individual coyote personalities and the profusion of family interactive behaviors, along with the simplest basic guidelines for coexistence. Reproduction of the photos appear a little grainy in these online versions, but that several depict strong social interactions is very clear.

Hopefully the article will help open the door to recognizing that there are commonalities between species vs. “denying these similarities because we’ve been told that animals couldn’t possibly have qualities or social drives that humans have”. Recognizing a kind of parallelism will help you relate to them better, and help you possibly appreciate who they really are.

Feedback I’ve been getting: The writeup is fun and informative! :))  I’ve included the above embedded copy of the article from Pacifica’s website, and a link to a PDF version, below, which might be easier to read.
PDF version: P_NOV2018-web

Continued DNA Study

Continued DNA study of coyotes in San Francisco is proceeding forward!

Professor Ben Sacks of UC Davis initiated the DNA study of San Francisco coyotes when he analyzed DNA from the first coyotes that re-appeared in San Francisco in 2002 after decades of absence from the city. It is his study which showed that these early coyote arrivals in San Francisco came from Mendocino County. Ben had previously discovered that markers differentiated various geographical groups of coyotes, and one of those groups he was able to isolate and identify was Mendocino coyotes. San Francisco coyotes matched these.

The study was expanded in 2008 with more samples (which I collected from throughout the city) whereby Ben Sacks’ graduate student, Katherine Marquez, studied the connectivity of our population to surrounding rural populations (2011).

And now we’re into yet another round of tests from scats I collected over the last four years from throughout the city, with many defecations occuring as I watched, so I know “who” they came from as well as their family relationships, among other things. So we already have a lot of information about these coyotes. Ben has generously and graciously taken on the DNA analysis of this project, which he’ll incorporate into his teaching. The earlier scats will be used as benchmarks.

My two main questions include, “To what extent and how are the coyotes in San Francisco related to one another?” This will show movement within the city, and will show to what extent inbreeding has occurred. And, “Are all or most of our present population descended from the original Mendocino group, or have some trickled in from south of the city?” Stay tuned for the results later on this year.

Note that DNA from scat is a totally non-intrusive, non-invasive way of collecting information about coyotes, beyond my dedicated direct-observations which take a lot of time. A lot of what we find out in this DNA study will be confirming what I already know through hours of observation and documentation, but even more of it will be revealing new information and connections.

Leath Tonino Captures My Joy and Viewpoint In Watching Urban Coyotes, in High Country News

2015-05-25

Click on the photo for a readable version of the article. Also notice that although only one photo displays at any one time at the top of the linked page, you can scroll through all seven of them by pressing the numbers below the photo. Leath Tonino, you’ll all note and agree, is a fantastic writer and has captured the spirit of my adventure perfectly!

I spent the twilight hours in a park with Leath where he interviewed me for this article as we watched a coyote, and I thoroughly enjoyed his company. He sent me another very creative article of his which is about adventure in exploring the urban wild right at your doorstep without driving hundreds of miles. Kudos to Leath! https://www.hcn.org/issues/47.6/raccoonboys-guide-to-urban-wilds

And, the really good photo of me was taken by Terray Sylvester, with whom I spent another thoroughly enjoyable park outing.