NATURAL VIEW: Will the real predator stand up?

There’s a flap at Cal State Long Beach about feral cats and coyotes on campus. Coyotes are stalking the cats, and the cat defenders want the coyotes removed. The university wants the cats to go, which would also eliminate the coyotes. Before choosing sides, let’s look at a few facts.

When a coyote lopes away, the limp body of a cat dangling from its jaws, who’s going to be sorry? You can be sure it won’t be the local birds. Despite the roadrunner-coyote cartoons, coyotes don’t spend their time chasing birds. We know what cats eat; they’re strict carnivores, meaning they eat meat. Coyotes, however, are opportunistic omnivores because they eat everything. Ever see a cat eat berries or prickly pear cactus fruit? Cactus and other seeds are commonly found in coyote scat in Laguna Canyon Wilderness Park. To be sure, coyotes take woodrats, mice and rabbits also, but much of their calories come from plant food.

In fact, from the standpoint of the campus birds, the coyotes are heroes. Every feral cat removed means many dozens of birds will survive.

“The Death of Nature,” by biologist John Terborgh, claims there are 100 million feral cats in the U.S. In England, a yearlong study of the hunting patterns of village cats discovered that the average pet cat eats 200 birds and mice a year, despite being fed at home. A feral cat has to eat substantially more.

In the late 1970s, we had several years of low rainfall. Coyotes and other hungry predators moved into my Laguna Canyon neighborhood. Many domestic animals vanished, cats included.

With the cats gone, small animals flourished. Freed from the threat of their worst predator, brown towhees and sparrows scratched on the ground with impunity, and many lizards appeared. My garden was alive with them as they scuttled under the plants, dashed out to catch insects, or pumped up and down on the woodpile. Snakes even moved down from the hillsides, much to the delight of my daughter. What we saw was “ecological release,” or “when the cat’s away, the mice all play.” Besides feral cats, coyotes reduce the number of raccoons, foxes, skunks and opossums. They don’t necessarily eat them, but they discourage them. These animals are called “mesopredators,” meaning they’re mid-sized. They are also major predators of birds and other small wildlife, like mice and lizards.

In several important studies of wild canyons in San Diego by ecologist Michael Soule, coyotes made the difference between keeping small wildlife around or losing them in fairly short order.

Canyons large or connected enough to other wildlands to have coyotes also had thriving native bird and small mammal populations.

Native wildlife in canyons with no coyotes was eliminated by the assault of foxes, raccoons, skunks, and feral cats. Nonnative birds, rats and mice from adjacent development replaced them — pigeons, starlings, house sparrows, roof rats, house mice, etc.

Coyotes are thus a “keystone species,” critical in preserving some of the natural biodiversity of our local coastal scrub.

That’s why wildlife agencies are careful to leave coyote corridors between wild areas when development encroaches.

Finally, coyotes and cats can coexist — if the cats are inside.

ELISABETH M. BROWN is a biologist and the president of Laguna Greenbelt Inc.