Island Foxes May Soon Die Out, Scientists Warn

Wild foxes could become extinct at Channel Islands National Park by the end of the year unless immediate and drastic measures are taken to save their fast-dwindling population, experts warned Friday.

After a series of emergency meetings in Ventura this week, scientists are urging the National Park Service to remove many of the island foxes remaining in the wild and put them in a kennel to protect the few that are left.

The extraordinary step, usually reserved for animals in critical condition like California condors and some bighorn sheep, presages plans to rebuild fox populations on three park islands through captive breeding.

“Their low numbers now place them in a very critical stage,” said Robert K. Wayne, biologist at the UCLA department of organismicbiology, ecology and evolution. “We’re talking a matter of months or weeks maybe before these populations disappear. The situation is really in a crisis mode. We don’t know if we are going to save them or not.”

Numbers of foxes on Santa Cruz, Santa Rosa and San Miguel islands--half the islands where they live and once home to the most robust populations--have dropped by 90% in four years. Disease, loss of shrubby habitat and predatory eagles contribute to the decline, although scientists emphasize they do not understand how the threats work in concert.

Only six foxes are known to remain on San Miguel Island, where about 450 were present five years ago. A few dozen appear to be left on much larger Santa Rosa and Santa Cruz islands, down from more than 1,200 over the same period. Fox populations are holding steady on southerly Channel Islands outside the park, including San Clemente, San Nicolas and Santa Catalina islands, where distinctly separate subspecies live.

Park Service officials summoned a team of 17 experts in wildlife biology, captive breeding and diseases to park headquarters in Ventura for a summit Wednesday and Thursday to assess the situation and recommend strategies to save the species. It was the first time scientists convened to share notes and assemble a full picture of the animal’s plight. They left the meetings dismayed and presented the Park Service with a list of recommendations to be implemented immediately.

“The picture is much bleaker than I anticipated,” said Brian Walton, director of the UC Santa Cruz Predatory Bird Research Group.

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Among the proposals, the scientists recommend capturing 20 wild foxes from two islands to place in captivity. Scientists say the unusual step would ensure at least some animals survive by providing them safe harbor from predators, parasites and malnutrition. Some must be collected immediately, the scientists recommend, although many would have to depend on their wiles to make it past June, when pups are weaned and adults can be rounded up. The end result could mean no wild foxes will be left on San Miguel Island, where losses have been greatest, the scientists said.

The move is considered the first step toward a captive breeding program, which the scientists concluded is essential to rebuild fox numbers.

However, foxes bred in captivity should not be released to the wild until environmental conditions that imperiled the species in the first place improve. In the meantime, researchers will concentrate their studies on wild foxes remaining on Santa Cruz Island to better assess the threats.

“We have to do something immediately. We’re going to have to use captive breeding to save these populations,” said UCLA biologist Gary Roemer.

Eagles are also targeted for intense management. The scientists recommend trapping and removing golden eagles from the island. The eagles are devouring young foxes at an alarming rate. In their place, scientists recommend restoring bald eagles at Channel Islands National Park. They chase away golden eagles, eat more fish than mammals and were once a native species at the park before they succumbed to DDT, Walton said.

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In June, the scientists plan to reconvene and present a comprehensive draft recovery plan for the foxes. They also recommend petitioning the U.S. Fish & Wildlife Service to list island foxes as protected under the federal Endangered Species Act. Some researchers, however, expressed doubts that protection could come fast enough to help the animals and might actually slow recovery efforts with paperwork and interagency consultations. Island foxes joined the state list of threatened species in 1971.

Channel Islands National Park biologist Tim Coonan said all the recommendations submitted by the scientists will be implemented as rapidly as possible. However, the measures will cost more than the park can afford this year, requiring additional funding, although he was unable to provide an estimate. The Park Service is working with the Washington, D.C.-based National Park Foundation to launch a “save the fox” campaign to raise money.

“We find ourselves at a critical juncture in management of this unique species,” said Channel Islands park Supt. Tim Setnicka in a statement released April 6. “We have documented a tremendous decline and we have identified some of the major factors causing this decline. Now we must act quickly and decisively to bring about recovery . . . The island fox is truly a symbol of the Channel Islands and we are determined to turn their decline around.”

No bigger than cats and cute as plush toys, island foxes are one of the most endearing of California’s fauna. They descend from mainland foxes and like other island-dwelling mammals, shrunk over generations to fit their Channel Islands confines. Long protected from predators by ocean, they show little fear of humans and act almost tame, endearing them to the researchers who handle them.

“They look like a mainland gray fox, except it’s ‘Honey, I shrunk the canids,”’ said Rich Block, director of the Santa Barbara Zoological Gardens. “They look like they got shrunk in the spin cycle. It’s a beautiful, small animal that generates interest and is very charismatic.”

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Six of the eight islands off the Southern California coast have fox populations that are genetically and morphologically distinct from one another, Wayne said. They are the biggest land-based mammals on some park islands and perform a vital role in the ecosystem as top predators.

“It’s a flagship species for the islands. It’s their panda,” Wayne said.

Katherine Ralls, a Paso Robles-based zoologist for the National Zoological Park of the Smithsonian Institution, said scientists may be too late in responding to the crisis. She said emergency actions should have commenced as soon as it was apparent fox numbers were in a free fall.

“We might lose them. The Park Service waited too long,” Ralls said. “You shouldn’t wait this long to start captive breeding. This is a park that is supposed to be at the forefront of scientific management of resources. At least they’re doing the right thing now.”

Coonan said the demise of the fox was so swift scientists were confronting a calamity before they could respond. Also, funds for fox research were slow in coming because the animal is not listed as a federally protected species, he said.

Human-induced changes to the islands’ fragile environment account for the demise of the foxes. Livestock grazing on the islands stripped away coastal sage scrub habitat they need for cover. Feral pigs that farmers released in the 19th century attracted golden eagles from the mainland.

Pesticide poisoning led to failed reproduction among bald eagles, allowing golden eagles to move in and devour foxes. Domestic dogs spread a type of worm that clogs the fox’s heart. UC Davis researchers announced at this week’s meetings they discovered a type of heartworm in island foxes that is common to European dogs, but has never before been seen in North America. No one knows how the parasite got to the Channel Islands.

Said Ralls: “We’ve messed them up so much.”