Story and photos by Chuck Graham
Kayaking around the Channel Islands National Park just wouldn’t be the same without those little, four-legged, cinnamon-colored island foxes ransacking my kayak, swiping my trail shoes or diving inside my dry bag.
If you come out to paddle at Santa Cruz Island today, you’re virtually guaranteed of seeing an endangered island fox, the little rascals bounding across the largest of California’s Channel Islands. That wasn’t the case 15 years ago when the chain’s largest land mammal teetered on the brink of extinction.
Today there are approximately 1,200 island foxes enjoying the most biodiverse island off the California coast. In 1999, during my first circumnavigation of the islands, there were roughly 55 island foxes looking over their shoulders, wary if their time was up. Back then a 5,000 strong feral pig population was responsible for luring over 40 golden eagles that had colonized the northern islands of the Channel Islands National Park (NPS). Taking advantage of the absence of bald eagles due to DDT poisoning, golden eagles soon realized it was easier to hunt island foxes than the scruffy swine.
The island fox populations on Santa Rosa and San Miguel Islands also plummeted due to golden eagle predation. Because island fox populations are subspecies of one another, if those populations were lost then that subspecies would be gone forever.
Conservation partners such as the NPS, The Nature Conservancy, The Institute for Wildlife Studies and the U.S. Fish and Wildlife Service (USFWS) implemented immediate conservation actions to address those threats and prevent the extinction of the island fox. A captive breeding program on each island played an integral role in recovery efforts, which was initiated in 1999 and ended in 2008. All captive-bred foxes were returned to the wild and vaccinated to prevent the spread of canine distemper. Additionally, golden eagles were trapped and relocated on the California mainland. The feral pig population was eradicated from Santa Cruz Island, and bald eagles were re-established to their historic territories.
Extinct from the islands since the 1960s, bald eagles are now thriving after aggressive restoration efforts began on the National Park in 2002 with 12 bald eagles released each year through 2006. A recent NPS report said there are now 50 bald eagles living in the park. Combined with Catalina, California’s Channel Islands recently reached an important milestone with the 100th bald eagle expected to soon fledge. There could also be a record 20 active bald eagle nests across the Channel Islands this breeding season.
Because DDT pesticides are still present near Catalina Island, restoration efforts there require biologists to lend a hand in the incubation process. That’s not the case on the National Park where DDT is less prevalent in the food web enabling bald eagles to hatch their eggs on their own. The restoration of bald eagles has been especially vital, because they’ve helped keep golden eagles at bay. Bald eagles scavenge marine mammal carcasses and hunt fish, not island foxes.
“There’s been no hint of golden eagle predation,” said Tim Coonan, terrestrial biologist for the Channel Islands National Park. “It’s great to be where we are.”
If everything continues to progress and things go as planned, in a couple of years the island fox could be removed from the Endangered Species List (ESA). If that’s the case, the island fox has the potential to be the fastest recovery of any land mammal in the history of the ESA.
“There’s plenty of data, over 20 years worth to make a decision,” continued Coonan. “The island fox will probably be delisted in two years. Endangered species average 25 years on the list. It’s really rare to get one off. Everyone sees a win, win with this though.”
In the mean time island fox populations across the northern chain are enjoying their return to a natural balance. In 1999 island fox populations on Santa Rosa and San Miguel Islands were dreadfully low. Each isle had 15 island foxes making captive breeding a real challenge to avoid any inbreeding. Today San Miguel Island is brimming with island foxes and is currently at carrying capacity of approximately 500 animals. Santa Rosa Island is a bit larger than its neighbor to the northwest and still has some room for more of the cinnamon-colored foxes. Historically Santa Rosa carried about 1,000 foxes. Today their population is around 700.
“The San Miguel population is putting itself back in check,” said biologist Robert McMorran of the U.S. Fish and Wildlife Service. “It can only harbor so many foxes.”
Even though populations are robust, conservation partners aren’t taking any chances. Captive breeding facilities remain on each island just incase of possible threats to island fox populations.
“If there are depressed population numbers due to golden eagles or canine distemper, then epidemic response plans are already in place,” he said.
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