Hardy Red Fox Called a Shock to the Ecosystem : Environment: Experts say the imported predator has threatened many native species and has to go. Animal rights groups oppose the move.

They may be cute, but a new report warns that those little red foxes found along the California coast pose a big threat to most ground-nesting birds, including several endangered species.

From the Ballona wetlands near Marina del Rey to the rugged Palos Verdes Peninsula to the Bolsa Chica Ecological Reserve in Orange County, the list of birds on the red fox’s menu includes gnatcatchers, quail, avocets, snowy plovers, and even herons and egrets.

At the El Segundo dunes next to Los Angeles International Airport, the foxes go after more than just birds. They have wiped out 17 of the 20 varieties of snakes, lizards, rodents and larger animals there.

This loss has shocked the ecosystem so severely that several endangered species such as the El Segundo blue butterfly and the horned lizard are now rare or extinct in the area.

Officials at the Madrona Marsh Nature Preserve in Torrance say there are no more ground-nesting birds in that wetland area because of the wily foxes. They hunt anything that moves in the marsh, including wild mallard ducks and the Easter bunnies set loose every year by parents whose children no longer want their pets.

“The threat is serious,” especially for the near-extinct clapper rails and terns, said Ronald M. Jurek, a wildlife biologist with the state Fish and Game Department and the author of the report.

What wildlife managers face is the case of a hardy outsider being introduced into ecosystems that have no defenses or protections against the red fox’s hunting skills. These cunning carnivores, native to the Midwestern and eastern United States, were brought to California years ago as targets for fox hunters.

Undaunted by sprawling urbanization, the foxes thrived and spread into the coastal canyons and wetlands, threatening native birds with extinction, according to experts. They den anywhere they can find shelter and food.

“We all like foxes. They’re cute, wonderful animals, but they’re like exotic weeds in these ecosystems; they don’t belong,” said Lloyd Kiff, director of the Western Foundation of Vertebrate Zoology and team leader of California’s condor recovery project.

The impact on the ecosystem has been particularly dramatic in the El Segundo dunes, said wildlife expert Rudi Mattoni, a consultant hired by the Los Angeles Airport Commission to restore the dune environment. The foxes den in the dunes and the nearby Hyperion sewage treatment plant.

“The (red) fox has become highly urbanized. We’ve got a huge population, maybe as many as 150 from the Ballona wetlands to Manhattan Beach,” Mattoni said.

Dozens inhabit the El Segundo dunes and “are directly responsible for the loss of many mammals out here, like the (endangered) pocket mouse,” Mattoni said. “Their impact on the ecosystem has completely eliminated the habitat of several species, including two kinds of butterflies.”

The story is the same up and down the coast, but controlling or getting rid of the fox is no easy task.

Federal wildlife refuge managers from San Francisco to Orange County ran into trouble when they started trapping and killing the foxes in the mid-1980s because the predators were killing clapper rails and terns. Fencing to restrain the foxes was too expensive and ineffective, and relocation was out of the question because no other state would accept the predators.

Shocked by fox killing in the Seal Beach National Wildlife Refuge, a group called Animal Lovers Volunteer Assn. filed a federal court suit in 1986. The organization contended that the foxes had been around long enough to be considered native and had as much right to life as the birds they ate.

The court refused to block the federal trapping and killing practices while the issues were argued. Last month, after six years of legal skirmishing, the federal court upheld euthanasia, ruling that protecting the endangered species takes precedence over saving the red fox. That ruling may not end the fight, however.

“We plan to appeal,” said Animal Lovers spokesman Hal Baerg of Huntington Beach. A coalition of other groups, led by the Wildlife Protection League, are supporting Baerg in the fight to save the fox, said Mary Sheehy, league president. They are demanding not only an end to the killing but want the use of leg traps outlawed as well.

For wildlife experts concerned about the fast-disappearing rails and terns, time is a problem. The fox may wipe out these endangered birds before the controversy over technique is settled, they say.

“How to deal with this threat is a major problem,” Jurek says. So far, nobody has come up with an acceptable way to control the damaging impacts of the foxes. Yet when they aren’t controlled, entire bird populations disappear, he reports.

Controlling the animals is not easy. Few predators can match their survival skills or ability to elude capture. They den in culverts, under pipes in sewer treatment plants and out between airport runways. One family eluded capture for days, delaying the opening of improvements to the Costa Mesa Freeway last year.

In the salt marshes around San Francisco Bay, the red foxes are now swimming out to tiny marsh islands and braving high tides to raid bird nests there, said Rick Coleman, manager of the 20,000-acre San Francisco Bay National Wildlife Refuge.

“Two years ago the fox totally wiped out heron and egret (nesting) colonies in one part of the bay,” he said. Though fencing of individual plover nests has worked, he said high tides and high costs make fencing the clapper rail nesting areas impossible. There, only trapping works, he said. Clapper rail numbers have plummeted from 1,200 nesting birds 10 years ago to only 300 or 400 now, he said.

“Unfortunately, we’re dealing with a situation where (society) has screwed up the environment so badly we’ve lost 80% or more of the clapper rail habitat and introduced an animal (red fox) that the rails never dealt with before,” Coleman explained.

The red fox was imported, primarily from east of the Mississippi River, state Fish and Game Department experts say. By the 1940s the state had 125 fox farms, and the foxes either were released for hunting or escaped, said Esther E. Burkett, a wildlife biologist writing in Outdoor California, a state Fish and Game Department magazine.

Animal rights activists contend that the state Fish and Game Department’s official history is skewed against the red fox. They claim the red fox is a native, or nearly so, and that the birds are disappearing for other reasons, including the loss of habitat and environmental pollution.

“We feel the (red fox) has been here more than a hundred years, they are a part of the ecosystem and it is detrimental to take them out of that system,” said Jill Morris, attorney for Baerg’s Animal Lovers group. “The problem can’t be solved by killing the fox.”