Between a fox and a hard place
Scientists say protected golden eagles threaten endangered Channel Island fox.
By NATHAN S. WELTON
South Coast Beacon

So here’s a quandary:

A team of scientists has recently announced that the only way to save the threatened Channel Island fox from extinction requires shooting a few federally protected golden eagles — which eat the foxes — and then ‘eradicating’ countless feral pigs.

Kill off one protected animal, as well as a few pests, and you save another.

Sounds strange, but that might be the future of 21st Century wildlife management.

“Due to overpopulation and over-utilization of our resources, we’re going to continually face a biodiversity crisis and we’ll have to make difficult decisions,” said Gary Roemer, a New Mexico State University biologist and an expert on the island fox populations. “But if you want to stem the tide, these decisions have to be made. And killing golden eagles is an example.”

Roemer and his colleagues recently released a study in the journal Science that outlined the plight of the diminutive Channel Island fox, brought to the verge of extinction through none other than the hands of man.

When humans introduced pigs to the islands, and when the populations of native bald eagles declined due to DDT, goldens descended from the skies, began breeding on the islands and fed on the pigs. Bald eagles – never particularly interested in eating the native foxes – had until then kept the goldens at bay, but the new avian tenants grew to such numbers that they started hunting both the piglets and the housecat-sized foxes.

“We’ve identified golden eagle control as the single most important recovery action for the foxes,” said biologist Bridget Fahey of the U.S. Fish and Wildlife Service.

Eagles killed 85 percent of the 47 radio collared foxes found dead since 1994.

In the last decade, due presumably to golden eagles, fox populations on the islands have crashed: the number on Santa Cruz Island has dwindled from 1,500 to around 65, while those on San Miguel and Santa Rosa have gone extinct in the wild and survive only through a captive breeding program. Populations on the three other isles are faring better, but aren’t exactly healthy.

The decline has reverberated throughout the island ecosystem: one island experienced a huge boom in skunks afterwards, said Roemer, while another saw some of the highest mice densities ever recorded. In addition to stabilizing the other fauna nosing around, the foxes’ vegetarian tendencies help disperse seeds.

“They are what you’d call a highly interactive species,” said Roemer, marveling at the ecological importance of the animal.

Existing management practices call for capturing the eagles and killing off the pigs, which would theoretically reduce the eagles’ food supply and force them to hunt elsewhere. With fewer eagles, there might be less pressure on foxes, and scientists could release captive-bred animals into the wild.

“Is there a chance that there’s a threshold where some level of foxes and some of eagles can coexist?” asked Park Superintendent Russell Galipeau, justifying his decision to avoid lethal removal and release foxes — twice last month and twice later this month – in the presence of eagles.

But Roemer and his colleagues — and their mathematical models — see a different story. Removing the pigs first, said Roemer, could cause the birds to eat nothing but foxes.

“We’re suggesting that this would place more pressure on the foxes, and in my view that’s a potential outcome I’d not want to take,” he said. “Do you want to take that chance? Do you want to cause another population to go extinct in the wild?”

So the goldens must go, he said, and it’s an opinion supported by ad hoc group of scientists comprising the Island Fox Conservation Working Group. If lethal removal is necessary, say some biologists, so be it.

Roemer and his colleagues, however, are not advocating willy-nilly target practice; they’re calling for the capture and removal of as many birds as possible. The leftovers, however many of the remaining 8 goldens that have so far eluded trappers, should be shot as a last resort.

What makes the whole situation thorny are the political, legal and ethical overtones of lethal removal.

“The rat eradication (of a few years ago) was really controversial, an uphill battle, and that was a rat that’s not protected,” said Fahey, noting that the golden eagle is protected by two federal laws and a state law.

“If we do decide lethal removal is necessary to save the foxes, I’d anticipate a long process,” she said. “We’d need to get permits, we’ll need to work with the state and the Park Service and the Nature Conservancy to make sure everyone’s on the same page, and we’d want the public to be on board because these are their resources.”

But Roemer said such stalling is typical of government agencies at the whim of congressional control, public outcry and bureaucratic red tape, and noted that time is now critical. With each passing month, he said, the foxes in captivity age, they’re less likely to breed and they’re less likely to function successfully if reintroduced.

“I can say what should be done,” he said, “but whether or not that’s a real world issue is another thing.”

Still, if wildlife officials agree on one thing, it’s that ecological balance is increasingly difficult to achieve.

“Unfortunately, in the world we live in, the environment is getting more complex, “ said Galipeau, “And the decisions we’ll have to make are going to get more and more controversial.”