They’re the only canid that can climb trees as easily as cats.
And about the size of a house cat, the gray fox is a charismatic yet relatively little-known species.
From urban populations figuring out ways to adapt to life in the margins between green space and city development, to unique subspecies found only on a chain of islands in the Pacific ocean, gray foxes have fascinating stories to tell.
Gray Foxes of Silicon Valley
Amid the tech centers and traffic of busy freeways criss-crossing Palo Alto, California, lives a surprising resident of the city: the gray fox. For six years, Bill Leikam and Greg Kerekes of the Urban Wildlife Research Project have been documenting a population of gray foxes living around a small, six-acre marshland.
The foxes in their study area have staked out territories next to industrial buildings, apartment complexes, golf courses, landfills and yes, right near the busy and deadly 101 freeway. Watching the foxes’ daily struggles in navigating uniquely urban dangers, the team is mapping out the creeks, culverts and other corridor passageways that the foxes and other wildlife use to move between hunting grounds or to disperse to new areas. These corridors are critically important, and the local gray foxes are helping to highlight which are in need of restoration and protection.
Channel Island Gray Fox: A Record-Breaking Recovery
Channel Island foxes (Urocyon littoralis) are a unique species of fox living on the Channel Islands off of southern California. The species decreased to critically endangered levels in the 1990s. In 1999, the subspecies found on Santa Catalina Island faced a 95 percent population decline in that year alone, with only 103 individuals remaining. The cause was an outbreak of canine distemper brought onto the island by a domestic dog or raccoon.
While the situation was dire, researchers acted quickly and effectively. The Channel Island foxes experienced the fastest recovery of any endangered species in history. A mere 12 years after being listed on the Endangered Species List, three of the four subspecies listed were removed and Santa Catalina Island’s population was downgraded from Endangered to Threatened.
Two of the subspecies — the San Miguel Island fox and the Santa Rosa Island fox — were down to a mere 15 individuals each. They now number about 577 and 894 respectively. And the Santa Catalina subspecies is stable at an estimated 1,500 individuals.
Julie King, a biologist with the Catalina Island Conservancy, along with a small team of researchers are in the field ensuring the population remains stable. This includes trapping foxes to vaccinate, microchip, collar, and otherwise monitor the health of the island’s foxes.
Though the foxes experienced a speedy recovery after near-extinction, the ongoing existence of human-made challenges means conservation efforts must continue in perpetuity. These challenges include: habitat degradation from introduced ungulates, including bison and deer; rodenticide poisoning from local homes and businesses; vehicle strikes, and the continued spread of disease introduced by domestic dogs.
Follow along as more stories of unique gray fox populations unfold.