'Dwarf' foxes, saved from extinction, make an incredible recovery

island fox pup photo
© National Parks Service

While they may be a bit smaller than your average house cat, what these 'dwarf' Island foxes lack in stature, they make up for in resilience.

Not long ago, the future looked bleak for the distinctly diminutive fox species that reside on California's Channel Islands. In the mid-1990s, the island fox's numbers had plummeted from the thousands to, in some cases, just over a dozen -- raising alarms that the species would soon be extinct and prompting them to be classified as a 'critically endangered' species.

But now, after a few short years of incredibly well-executed conservation tactics, biologists say that the tiny canine has made one of the fastest recoveries of any animal in the history of the Endangered Species Act.

The history of the island fox's decline offers a lesson on the interconnectivity of nature. Bald eagles were once common along the Channel Islands, feeding mostly on fish while the foxes feasted on insects, birds, and other land mammals. Exposure to the now-banned insecticide DDT, which washed into the ocean and contaminate their diet, caused bald eagles to die off -- opening the skies over the islands for a new bird of prey to take hold.

Soon enough, golden eagles from the mainland began to settle in the Channel Islands, unchallenged. Thanks to a skyrocketing population of feral pigs on the islands, the newly-arrived golden eagles were well fed -- though they also developed a taste for the little foxes.

One biologists has called it "a perfect storm of events" which might have ended the island foxes for good.

The population declines were jaw-dropping. Foxes on Santa Rosa Island, for example, which numbered 1,500 in 1994, were reduced to just 15 individuals by the year 2000. The other five subspecies fared either equally, or little better. By 2004, the foxes were added to the Federal Endangered Species List.

That's when officials from the National Park Service and the Nature Conservancy stepped in, initiating a multi-faceted plan to stave off the fox's seemingly inevitable extinction. Hunters were hired to thin the number of grazing sheep and feral pigs, while wildlife officers meticulously set about capturing the golden eagles and relocating them to the mainland. Meanwhile, several captive-breeding programs were established to boost the island fox populations.

By 2006, officials captured the final two golden eagles.

"The last golden eagle pair was really tricky to get because they had seen all their buddies get captured," says Christie Boser of the Nature Conservancy. Bald eagles have begun to be reintroduced in their place.

With those threats from above eliminated, biologists expected the island foxes to regain their footing -- but no one could have guessed just how quickly they would recover. Incredibly, after hitting a low of 15, there are now 600 foxes on Santa Rosa Island. The other islands are also seeing huge recoveries, with 500 foxes now on San Miguel Island, and a whopping 1,300 on Santa Cruz Island.

"It's a strange thing," says NPS biologist Timothy Coonan. "The official recovery plan has not even been finalized [by the U.S. Fish and Wildlife Service], and yet these populations are doing so well that they can come off the Endangered Species List."

According to the National Park Service, after reaching declines of 95 percent just a decade or so ago, the fox population today has nearly recovered -- adding that "population trend and annual survival are currently monitored to ensure that recovery proceeds apace and future threats to the park's island fox subspecies are identified."

It may be true that humans are the most apt species when it comes to manipulating the environment, but that ability needn't always be used to harmful effect. The success of conservationists to restore balance to the Channel Island ecosystems, once again thriving with dwarf foxes, serves as a living monument to what is possible when we work in harmony with nature -- fragil as it may be, but at the same time, so incredibly resilient.

'Dwarf' foxes, saved from extinction, make an incredible recovery
While they may be a bit smaller than your average house cat, what these 'dwarf' Island foxes lack in stature, they make up for in resilience.

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