These foxes were filmed in Pennsylvania.
Grey foxes and raccoon dogs are the most primitive of wild dog species. They both retain their ability to climb trees. All dogs derive from tree climbing ancestors. Most dog species have developed in to carnivores that run on the ground and have lost this ability.
Grey foxes are in their own genius. The mainland grey is the most common species, but two other species exist, although one may be extinct. The island fox lives on the Channel Islands off the Coast of Southern California, where each island has its own subspecies. The foxes have suffered as introduced species have come to the islands. One population of these foxes was destroyed when the bald eagle population crashed. The bald eagles kept the golden eagles off the island. Bald eagles are mainly fish predators. Golden eagles eat foxes, and as soon as they colonized the islands, they began eating the foxes.
Cozumel fox is also a close relative, but it may already be extinct. It lives or lived on Cozumel, Island in Mexico.
The mainland grey fox has a wide range. It is sometimes spotted in Canada, especially Southern Ontario and the parts of Quebec that border on New York and New England. It also has been found in southern Manitoba. It also is found in American Southwest through most of Mexico. It is found on the Pacific Coast of Central America, and populations exist in Colombia and Venezuela.
An article on the grey fox can be found here.
At dusk, I have seen gray or black foxes at my home in Northern California, inland Mendocino County. They seem much slimmer and darker than the one on the video shown here, and I don’t think they are escapees from a breeding facility, since I have seen them for a couple of years now. My housemate has even seen a baby of this coloration, so they’re clearly succeeding in the wild. Haven’t seen any of the usual red variety on this property, but I know they’re common even further inland, in the hills.
Are you within kit fox range?
http://www.mnh.si.edu/exhibits/mammals/KitFox.HTM