Catalina Island Foxes Brought Back from the Brink of Extinction Facing New Threats

Story at-a-glance -

  • Distemper virus nearly decimated the Catalina Island fox in 1999, but a recovery program has brought the species back from the brink of extinction
  • As the number of Catalina Island foxes has grown, so, too, have their run-ins with human residents
  • In 2014, at least 25 foxes died due to vehicle collisions, drowning in uncovered water containers, run-ins with dogs, or eating rat poison
  • The Catalina Island Conservancy has launched a program to raise funds to purchase animal-proof trash containers, which would help eliminate trash spills that attract foxes to roadways and other heavily inhabited areas

By Dr. Becker

The Catalina Island fox is a descendent of the gray fox. Weighing in at just four to six pounds as adults, these foxes are about 25 percent smaller than mainland foxes – and they’re only found on Catalina Island, which is one of California’s Channel Islands.

It’s unclear how the foxes originally came to inhabit the island, some 4,000 years ago. They may have floated over on debris or been brought by the island’s first human residents. Either way, the foxes, which are the island’s largest terrestrial predator, flourished… until 1999.1

That year an outbreak of distemper virus, thought to have been brought to the island by a raccoon that stowed away on a boat, decimated the fox population. Their numbers plummeted, from about 1,300 at the start of the outbreak to just 100 near the end. Christie Boser, California islands ecologist for the nonprofit The Nature Conservancy, told the Orange County Register:2

“We’ve checked their blood and they have very little resistance to disease… They haven’t been exposed to diseases with the same frequency as mainland animals.”

Conservancy Efforts Bring Back the Catalina Island Fox from the Brink of Extinction

In 2000, the Catalina Island Conservancy and the Institute for Wildlife Studies formed the Catalina Island Fox Recovery Plan. It included relocation, vaccinations, captive breeding and release programs, along with population monitoring, to help restore the wild fox population.

By 2004, the same year they were listed as a federally endangered species, the foxes’ population had grown to 300. By 2014, there were an estimated 1,700 foxes living on the island, which is more than existed before the 1999 distemper outbreak.

The recovery plan has been a success, and was also helped along by an important geological feature that prevented all the Catalina Island foxes from contracting distemper. The Orange County Register reported:3

“On Catalina, a narrow, quarter mile-wide isthmus separates the east and west ends of the island and limits cross-island migration to one fox per year. That spared the animal: foxes on the west end, away from the cities of Avalon and Two Harbors, didn’t contract the disease.”

The foxes are doing so well that officials are considering removing them from the endangered species list by 2017. Hopefully this will not be premature, as a new threat is now facing these resilient creatures…

Run-Ins with Humans Costing Foxes Their Lives

As the number of Catalina Island foxes has grown, so, too, have their run-ins with human residents. According to Discovery News:4

The conservancy says in 2014 at least 25 foxes died on the island. Most (21) were due to the animals being hit by cars, while other causes of death included drowning in uncovered water containers (2), run-ins with dogs (1), and ingestion of rat poison (1).

A mundane-seeming, but deadly nexus for these fox deaths has been trash cans, the conservancy said. Many of the island's dead foxes have been found near refuse containers, whose open or improperly secured contents lure the foxes into areas populated by humans, and their cars.”

Part of the problem is the foxes have no fear of humans or cars. Rather than running for cover, the curious foxes may try to look into your car window. Julie King, the Catalina Island Conservancy’s director of conservation and wildlife management, noted:5

“They have evolved without predators. They don’t view humans or cars as a threat. If you stop, they will often run around the car and stop by the driver’s side and look up at you.”

In response to the 2014 deaths, the Catalina Island Conservancy has launched a program to raise funds to purchase 150 animal-proof trash containers. The containers require a person to reach inside the covered lid in order to unlatch and open them. King explained:6

"Installing animal-proof trash and recycling receptacles will prevent the foxes and other wildlife from entering the containers and help eliminate trash spills that attract the foxes and other wildlife into inhabited areas and roadsides, where they may be struck by a vehicle."

If you’d like to get involved, you can make a donation to the Catalina Island Conservancy to help them purchase animal-proof trash containers. Catalina Island foxes are found nowhere else in the world – they only live on Catalina Island, so protecting them is of utmost importance.