Defenders Magazine

Foxy City

As their native habitat disappears, San Joaquin kit foxes carve out a niche in an unlikely locale

by Heidi Ridgley

© Steve Maslowski

Some wildlife biologists must slog through swamps, crawl through prickly underbrush or sit patiently in extreme temperatures in hopes of getting a glimpse of the elusive creature they’re trying to study. Not Brian Cypher, a biologist tracking the federally endangered San Joaquin kit fox in California. For him, it’s as simple as setting up some cages near the ninth hole at the Seven Oaks Country Club in Bakersfield—right next to a sign that reads “kit fox habitat”—and in the animals go, lured by hot dogs and bacon bits.

“The foxes love to dig holes in fairways,” says Cypher, pointing to the lush, manicured grass.

The country club has embraced the foxes, so much so that when workers noticed them hanging around, club officials allowed Cypher and his team from the Endangered Species Recovery Program (a cooperative project between the U.S. Fish and Wildlife Service [FWS] and the Bureau of Reclamation, administered by California State University at Stanislaus) to install artificial burrows. The housecat-sized foxes—a subspecies of kit fox and the smallest canid in North America—took to the burrows almost immediately.

The dozen or so kit foxes that now roam the fairways at Seven Oaks—mostly after dark, when these nocturnal animals do their hunting and scavenging—are among a few hundred foxes that improbably inhabit Bakersfield, California’s 11th largest city. That these rare animals have found a niche in this bustling metropolis is a mixed blessing. Some conservationists worry they are drawing attention away from retaining what little is left of the animals’ historical habitat in outlying areas. Yet, the Bakersfield population is a boon for researchers trying to figure out which individuals would make the best candidates for relocation and reintroduction into their natural environment, where fewer than 3,000 probably still exist.

Of course, the two caged foxes who are about to get poked and prodded on the golf course this morning—an adult and a pup—don’t realize it’s for their own good and the good of their species. But they also don’t protest too much. A few slaps to the top of the cage and the pup shoots straight into the denim bag attached like a chute to the cage opening. The adult hisses, makes a noise akin to a quack, half-heartedly lunges at Cypher through the bars, changes his mind and then darts into the bag. A quick twist and the bags are shut and carried to tarps spread out on the turf. “We don’t have to drug them this way,” says Cypher. “And then there’s no worry they’ll stumble into a dog, the street or a pond before it wears off. We just use manual restraint with the bag and only expose the part we need. Kits are naturally kind of docile and usually there’s barely a struggle.”

The biologists go to work, running their gloveless hands along each bag in search of a fox’s rear end. Simultaneously kneeling down with the upper half of the animals’ bodies tucked between their thighs, each biologist exposes a fox’s posterior and plucks some hair for DNA sampling. Then each bag is turned again and out pops a head held firmly by the neck. The biologists add an ear tag, check for fleas and get a tissue sample from the ear for further DNA testing. Finally, the pup gets a radio collar.

That’s when he’s had enough and begins a slow growl. When it crescendos in an open-mouth hiss, in goes a long, wooden dowel to keep his mouth pried open. Everyone leans forward to examine his teeth while the young fox’s eyes, which look like shiny pools of liquid ebony outlined in kohl—pigmentation that protects him against the fierce desert sun—dart from face to face. “They look good,” says Cypher. The adult’s also appear none the worse for wear. “His teeth don’t look as lived in as his ears and face,” says Samantha Bremner-Harrison, a biologist on the team who is applying her doctoral research on swift fox behavior to the recovery of its slightly smaller cousin.

And then it’s over. The pup is deposited from the bag directly into the artificial den, an inconspicuous grass mound about 2 feet high with a 6-inch-wide opening supported by plastic tubing. The adult is released to the open. “We’re not sure if this is his den,” says Bremner-Harrison. The fox hesitates. His bushy, tapered tail—at 10 inches it’s as long as the rest of his body—is larger than a puffed out housecat’s. Then he disappears down the same hole as the pup. Bremner-Harrison picks up the leftover hotdogs and drops them in after him. “It’ll be their reward,” she says.

The kit fox’s natural diet consists of rabbits, kangaroo rats, insects, mice and cactus fruits. But in the city, the sky’s the limit. One golf course burrow entrance is strewn with a burrito wrapper, a packet of ranch dressing, pieces of bird and tamale husks. Inside the den, a tunnel may stretch as long as 5 feet before ending in a chamber. “Often they take the easy route and take over a ground squirrel burrow, expand exploratory holes that badgers have dug or take over a giant kangaroo rat’s abode—after they’ve eaten the occupant,” says Cypher. “But they can dig dens themselves and be amazingly rapid about it. It’s not unusual for a den to appear overnight on a construction site.”

In fact, Bakersfield residents who keep their eyes peeled can see the little foxes so often that they might find it hard to believe that the San Joaquin kit fox is an endangered species, says Cypher. But that these stragglers survive here is more happenstance than anything else. As desert-adapted animals with pale, thick, fur coats that insulate against both heat and cold, the foxes prefer dry, open habitat—much like what surrounded Bakersfield until the middle of last century. As their native habitat has been converted to farms, factories and housing, the kits have been forced to find open spaces within the city—claiming not only a golf course, but a college campus and even a narrow grass meridian in the parking lot of an oil company’s headquarters.

“The worry, though, is that in such close quarters all you need is a strain of distemper to run through the population and it can be decimated,” says Kim Delfino, Defenders’ California program director. “We need to build strong populations elsewhere if the kit fox is to survive.”

To this end, Cypher is measuring more than the urban population’s survival rates, sources of mortality, reproductive success, dispersal rates and ecological needs. He is also evaluating personalities to see how individuals react to novel objects such as different foods or toy dogs. By comparing these foxes to those also being monitored on natural lands—to see which characteristics best help them survive—he hopes to determine whether it’s possible to use the urban population in reintroduction efforts and which individuals would be most likely to succeed. For example, would being bold increase survival odds or would that sort of curiosity kill the kit? “Traditionally, endangered species relocations consist of grabbing and dumping individuals without rhyme or reason,” explains Cypher. “This study could help save money, time and foxes by relocating animals that are more likely to survive in their new situation.”

But to relocate the foxes, natural habitat must still exist. The federal government’s recovery plan highlights three core kit fox areas. One is Carrizo Plain National Monument which, combined with land owned by The Nature Conservancy, provides more than 200,000 acres of relatively pristine kit fox habitat about 55 miles west of Bakersfield. “Arid shrub lands with sparse groundcover is the most suitable habitat for kits,” says Cypher. “A solid stand of grass is a jungle to these guys because they are easily ambushed by coyotes, their main predator in the wild. They are also tied to kangaroo rats, which drop out in dense habitat.” As desert-adapted species, these rats, which hop on large hind legs, also aren’t adapted to crops or the nonnative grasses now invading the valley. The vegetation hampers their movements, making them vulnerable to predators. When their numbers crash, so do the kits’.

A second area for the foxes is a mosaic of disjointed parcels totaling an estimated 300,000 to 500,000 acres and scattered throughout public and private land in western Kern Country about 30 miles west of Bakersfield. In the section called Lokern, the gray and brown saltbrush stands waist-high, scattered sparsely in the sand. “This may look like a vast wasteland but it’s actually incredibly diverse with species of snakes, lizards, rats and mice,” says Stephen Harrison, another of the team’s biologists. The land is zigzagged with the trails of kangaroo rats. So many, in fact, that you’d swear they couldn’t be on the federal endangered species list either. “It’s dry land,” he says. “If you leave your signature here, it’ll stay for years.”

All these features make it perfect kit fox territory—except for the two hazardous waste sites nearby and the miles of oil pipelines that run below the sand. Just a few miles south, past dust devils rising up and swirling in the noonday heat, sprawls “hell.” Proper name: The Midway-Sunset oil field. Another part of the Kern County recovery area, it’s known for its sulfur smell and billowing steam, remnants of the process used to release oil from the bedrock. The county is the third-largest crude oil production area in the country after Alaska and Texas and all around 15-foot-high oil derricks methodically pump up and down. But despite this disruption, studies have shown the area still supports more foxes than that of less-developed land in the county. “Midway-Sunset may look like Hades, but kit foxes can live here,” says Cypher. “It’s not so good for other critters, but kits are more mobile and adaptable. They can live between the wells.”

Cypher is not so sure about the Ciervo-Panoche Natural Area, about 100 miles northwest of Bakersfield and the third area deemed suitable habitat in the recovery plan. Foxes do subsist here, but it’s uncertain whether they are really a core population or just a “satellite” group trying to branch out and hang on, he says. Lands farther north, where foxes have also been intermittently observed, are even more marginal.

Not everyone is ready to write off the northern range yet, however. “The habitat is not as good as it is to the south because there’s not as much of it—it’s pinched between heavy agricultural land and coastal mountains—so there’s also not as many kit foxes there,” says Al Donner, assistant field supervisor at the Sacramento FWS office. “But we’re determined to protect this range to maintain the kit fox’s genetic diversity and to extend its range.” Up until recently, only a few rural towns existed here. Today, housing development is threatening to swallow up the habitat as population spills over from the San Francisco Bay area.

Not privy to the debate that surrounds them, it’s clear that kit foxes are intent on surviving no matter the odds. The next evening at dusk, Cypher is sitting in the parking lot of a Bakersfield shopping mall watching kit fox pups play on the hill that rises from the shoulder of an access road. “They’re not fussy about where they put their dens,” he says. The scene borders on the absurd: One yearling family helper stands guard as five pups frolic like kids, playing under a streetlight, tumbling down the hill, leaping over one another, turning on a dime, dodging one another around a tree. Every few minutes or so a person drives by, eyes straight ahead, oblivious.

Three years ago, a kit fox family got buried alive here by maintenance workers who blocked the entrances to their den. This is the first year a new family of foxes has reclaimed the area. Maybe, with a little luck and a lot of help, other kit foxes intent on surviving will reclaim lost land and thrive in more suitable habitat. “When we get further along with this study, we’ll start talking to the state and the feds about relocations,” says Cypher. “If nothing else, we’ll have a series of recommendations so they’ll have a blueprint in hand.”

Senior Editor Heidi Ridgley traveled to "hell" and back to write this story. Send your comments about this piece to: mageditor@defenders.org