Endangered Santa Cruz Island Fox Back from the Brink

Celebrating the five-year anniversary of the remarkable comeback of the Santa Cruz Island fox.

Five Years Later, the Island Fox Survival Rate Has Increased to 96 Percent

When the Santa Cruz Island fox population fell from 1,500 to fewer than 100, The Nature Conservancy launched an intensive recovery effort that saved the indigenous fox from extinction. And it has been one of the swiftest recoveries in history!

Today we celebrate the remarkable recovery of these gorgeous animals. Under rigorous conservation management, island fox survival rate has increased to an astonishing 96 percent, with approximately 1,300 of them thriving on Santa Cruz Island.

How did the Santa Cruz Island fox dwindle from 1,500 to fewer than 100 in less than a decade? The foxes and native bald eagles, which eat mostly fish, co-existed peacefully for hundreds of years. The four-pound foxes considered themselves top dog on the island, having evolved without threatening predators. Their resulting unique naiveté makes them appealing to humans but also more vulnerable to new threats.

An Ecosystem Unraveling

In the 1850s humans began introducing grazing farm animals to the island—and over many decades these animals drastically changed the natural island landscape. Bald eagles started to vanish in the 1950s, victims of exposure to DDT poisoning in their ocean food supply. The island was left void of most natural vegetation and the friendly bald eagle.

In the 1990s golden eagle populations on the mainland were increasing, and soon these predators starting eyeing an abundant island food supply of feral pigs and, unfortunately, the tiny fox. Within just a few years the island foxes were decimated by this voracious new predator.

Balance on the Island

In 2002 The Nature Conservancy, the National Park Service, U.S. Fish and Wildlife Service and the California Department of Fish and Wildlife launched a collaborative recovery effort to save the fox. We started by bringing 20 foxes into captivity to protect them from predation and increase their numbers in a captive-breeding program. Then we began relocating the golden eagles to the coastal mainland, removing the feral pigs and successfully reintroducing bald eagles to the island.

After six seasons the captive foxes could be safely released, and an astonishing 85 new fox pups were introduced into the wild. The recovery of the wild fox population was so successful that the captive breeding program was suspended in 2007. Five years later, the population has nearly reached historic numbers.

Fastest in History

The Santa Cruz Island rescue effort is lauded as one of the swiftest and most successful endangered species recovery programs in U.S. history.
The wild foxes are monitored using radio collars, vaccinated annually for rabies and canine distemper and living happily once again in their Island paradise. The fifth anniversary of their recovery is cause for a celebration!