The gray fox has been in North America for about three and a half million years, but in the Adirondacks only about a thousand years. It is the only member of the canid family in North America, to also inhabit Central America. They average two and a half to three and a half feet in length, with weights ranging from 8 to 16 lbs, with males generally larger than females. Life expectancy in the wild is about 7 years.

What distinguishes the gray fox from other foxes is its ability to climb trees with its powerful hooked claws, not only enabling it to escape would be predators like coyotes and dogs, but also allowing it to forage, hunt and even den in tree hollows. Gray fox can climb trunks up to 60 feet high, leaping from branch to branch, and descend cat style, rear quarters first. The gray fox was once the most common fox in North America, but the red fox is better able to adapt to living around human dwellings, and so is now the most common fox. Gray fox gave oval shaped pupils, while other foxes have slit-like pupils. The smaller Channel Island foxes of California, are believed to have evolved from gray foxes.

Mating season varies by latitude, with southern gray fox mating in January while northern fox in April. Dens are used while birthing or raising kits, and as a general home base at other times. Dens may be in rocky crevices, caves, log hollows and enlarged woodchuck or other rodent burrows. Gestation is about 53 days. As with other canids, gray fox are family groups, and Dad will help feed  the pups, who stay in or around the den, learning to hunt and forage, developing adult teeth by 4 months, beginning to hunt on their own, and finally dispersing from the den to begin their adult life after about six months, with the males eventually dispersing up to about 50 miles and females staying within a few miles of the natal den.

Gray fox are nocturnal and crepuscular omnivores, who consume voles, mice, rabbits and birds, grasshoppers and crickets, but also grass, corn, fruit, nuts, apples and berries, making gray fox even more omnivorous than red foxes..