Island Fox makes historical comeback
by Chuck Graham
Not so long ago, only 60 island foxes survived on Santa Cruz Island, and there were as few as 15 foxes each on neighboring Santa Rosa and San Miguel Islands, the isles’ largest land predator free-falling toward extinction in the Channel Islands National Park.
That was at the turn of the century when it was actually rare to see one of the cinnamon-colored foxes bounding through a campground or scampering up a fig tree. It was a time when opportunistic, nonnative golden eagles ruled the skies and, combined with an efficient ground game, the raptors nearly wiped out all three subspecies of island foxes.
By 2004 all three subspecies of island foxes had been added to the Endangered Species List. With an aggressive cooperative effort, however, led by the National Park Service, the Nature Conservancy, the Institute for Wildlife Studies and the U.S. Fish and Wildlife Services, the island fox rebounded as no other endangered species has before it and since the Endangered Species Act was established by Congress 40 years ago.
“The cooperative conservation effort that occurred was a real role model,” said Tim Coonan, who, for 23 years, was the lead terrestrial biologist at the Channel Islands National Park, and spearheaded island fox recovery from 1999 until he retired in 2015. “There were actions on the ground immediately, even before the island fox was listed.”
Beginning in 1999 and into the early part of the 21st century, a four-pronged effort ensued that changed the ecological landscape on the windswept, volcanic chain. Aggressive captive breeding took place for each subspecies of island fox on the three northern Channel Islands, because if one subspecies have been lost then it would have been gone forever.
The restoration of bald eagles — extinct from the islands for 50 years due to DDT poisoning — occurred from 2002 to 2006, allowing the iconic raptors to re-establish historic island territories. They also helped keep golden eagles at bay, which were lured from the mainland by the feral pig population on Santa Cruz Island that had grown to roughly 5,000, running roughshod across the mountainous islet. Eventually all 43 golden eagles were trapped and relocated to the California mainland. Bald eagles eat fish, not island foxes
By 2008 the last of the feral pigs was eradicated from Santa Cruz, opening the door for island foxes to flourish, which they have. Initially it was thought that Santa Cruz Island had a carrying capacity of approximately 1,200 to 1,500 island foxes, but current estimates shows a population infusion of around 2,500 animals on the largest, most biodiverse island off the Ventura coastline.
“They’re taking all of us a little by surprise,” said Robert McMorran, wildlife biologist for the U.S. Fish and Wildlife Service. “They will be the fastest mammal to be delisted under the Endangered Species Act.”
What’s even more astounding is how well the island fox has done during a time of extreme drought.
“I’m surprised,” continued Coonan, who now heads the nonprofit Friends of the Island Fox. “We really don’t know what the carrying capacity is on the larger islands.”
There’s plenty of room to roam on the northern Channel Islands, where the tiny island foxes have kept everyone guessing.