San Diego Last time Kevin Crooks crawled through a culvert under Genesee, he was thrilled to find tracks other than his own. "The culvert links Tecolote Canyon with a smaller canyon. I could see their tracks right along the drainage channel."
The tracks confirmed the presence in Clairemont of San Diego's most elusive neighbor, the coyote -- the "trickster," as Native Americans sometimes call it. Crooks says the name is appropriate.
"Where else in the world will you find such wild carnivores in the middle of the city?" Crooks says. "This is one of the most amazing animals I've studied, and he's among us right here!"
The reason coyotes survive in San Diego, he says, is our canyons. "L.A. is just one big flat ancient ocean basin. It doesn't have coyotes as we do. San Diego is an archipelago of canyon wildlife islands."
For three years Crooks, a 30-year-old graduate student at U.C. Santa Cruz, has been tracking San Diego's coyotes from Hillcrest to Mount Soledad to see how they survive and how they influence everything from native plants to pet cats. He plans to put the results into a Ph.D. dissertation.
"Coyotes definitely play an important ecological role in urban wild areas," he says. "It's been suggested that the disappearance of coyotes from fragmented [urban canyon] systems may lead to population increases of the smaller carnivores [such as] domestic and feral cats, gray foxes, raccoons, possums, skunks."
Crooks says these smaller carnivores prey on native species that live in the chaparral -- birds, small mammals, and lizards. "Possums and gray foxes eat birds' eggs, cats kill birds like the California gnatcatcher," he says. Already larger birds like the once-common roadrunner are becoming rare. "Of 30 canyons I studied, only one still had roadrunners."
Of course coyotes aren't perfect. "Coyotes will eat birds. They have been known to eat ground-nesting wetland species like least terns, so it's not that coyotes are completely beneficial to these birds. But their main diet is small mammals: rabbits, mice, rats, and a variety of vegetable matter: berries and fruits, both native and from people's groves and gardens."
When he began his study, Crooks was startled at the coyotes' ability to thrive in urban areas. "They're distributed near downtown San Diego and out towards Lemon Grove and Clairemont Mesa and in La Jolla and Solana Beach -- literally throughout the city. I've detected coyotes in Balboa Park, in canyons in Old Town and Hillcrest."
One thing that surprised Crooks was his discovery that coyotes are adept at moving from canyon to canyon. "Canyons such as the one right behind Heritage Park in Old Town have been isolated for at least a century. But that doesn't mean one population of coyotes has been [occupying] these canyons for 100 years. They're capable of moving -- at night -- from one canyon to another, making it through the streets or the storm drains and culverts."
Yet most of the people they live amongst aren't aware of them. "One of the most beautiful and secret canyons is near Mount Soledad," he says. "There are houses all around it, and then beautiful habitat, and yet it's not visited by people too much. I often walked into the bottom of this canyon, and the walls became narrower and deeper, so by the time you were down in the middle of the canyon, you'd be at the bottom of this little wash, and there'd be clay mud walls about 15 to 20 feet high, and then the shrub cover above you. But at the base is this big gorge. And that was where you had animal tracks. Fox, coyote. Great habitat. You get down in there and you forget you're in the middle of the city."
The irony is that in his three years, Crooks has rarely seen coyotes. His is discovery by evidence. "I've detected them by putting powder on the ground at 'track stations,' pouring a smelly liquid bait on a rock in the middle, then [later] looking for coyote tracks. I also look for coyote scat and set up remotely triggered cameras in some of the canyons, set off [when coyotes cross] an infrared beam, to get pictures.
"Occasionally, if I was out in the early morning, I'd see them poking their heads out. I've found them with dens, puppies, pairs, or running up the opposite end of the fragments. They definitely breed in Balboa Park. But I also saw they were breeding in canyons that were much, much smaller, the size of a couple of backyards."
Crooks isn't saying coyotes are angels. It's a dog-eat-dog situation when so-called canids -- the family of carnivores that includes wolves, coyotes, and foxes -- compete for the same resources.
In Central California's Carrizo Plain, one study showed coyotes killing more than a third of the foxes living within their territory. Wolves were known to control coyote numbers the same way. Mountain lions still do. Biologists are concluding that a larger predator defines a smaller one's range much more than food, habitat, or climate do. Crooks saw a graphic illustration of this recently. One day, walking around the rim of one of his canyons, he saw several coyotes surround a rottweiler that had wandered into the canyon. They were attacking the large dog with nips and harassment. He doesn't know if they killed it or not. He thinks probably not, given its size, although size doesn't always impress them.
"In large areas like Yellowstone Park coyotes will attack deer and elk in packs," he says. "Yet they very rarely attack humans, even kids. Domestic dogs are more likely to bite you than coyotes. It's safe to walk in these canyons."
Crooks says coyotes are teaching humans to become ecologically conscious. He sent out about 1500 questionnaires to people living around the city's various canyons to gauge their awareness of coyotes as wild neighbors and their attitude towards them.
"From my questionnaire data, nearly half of the cat owners, who believe there are coyotes in their canyon, restrict their cats outdoors because of the coyotes. Because coyotes occasionally kill cats, cats -- and their owners -- learn to behaviorally respond and avoid them. So there are fewer cats visiting the canyons and killing native birds. Thus coyotes are saving bird life."