Gray fox numbers on the decline in the Midwest

Long-time readers of my blog know that I have a long fascination with the gray fox (Urocyon cinereoargenteus). It is the most primitive of extant dog species, which apparently diverged from the rest of the dog family between 10 and 12 million years ago.  It might represent several cryptic species, though only the insular dwarf form from the channel islands is currently recognized as a distinct taxon. 

When I lived back in the woods in West Virginia, gray foxes were common trail camera captures. The video embedded in this post one of my best captures of the species. They were quite common in the backwoods of West Virginia, which has extensive, dense forests that are quite inaccessible to humans. These foxes prefer to live deep in the thicket, where they can always shoot up a tree if they ever feel threatened.

I now live in Northeast Ohio, and I have seen foxes here and in adjacent Pennsylvania. Every single one has been a red.

It turns out that gray fox numbers have greatly decreased in much of the Midwest, and  now researchers are trying to figure out why. 

A simplistic answer is that coyotes are killing them all. Coyote numbers are on the increase all over the Eastern and Midwestern US. But if coyotes were killing every fox they encountered, the numbers of red fox would have much more dramatic decline. Red foxes cannot climb trees, and they tend to hang out in areas where coyotes would likely encounter them more often, especially in agricultural areas.

But red fox numbers have not declined.

One possibility is that increased competition from growing raccoon numbers could have led to a reduction in gray fox numbers. Raccoons are not hunted or trapped nearly as intensively as they once were, and raccoons have a very similar diet to the gray fox, which is quite omnivorous.

Further, raccoons do carry canine distemper, a disease that is quite devastatingly fatal to gray foxes.

Now, coyotes carry distemper, and they also would compete for prey resources on which gray foxes rely.

So it is possible that the issue with coyotes and gray foxes comes from an indirect conflict, rather than outright predation.

The decline of the gray fox in the Midwest has wildlife researchers quite vexed. This problem coincides with a range expansion of the gray fox in the Northeast, a region that is also full of raccoons and coyotes.  Indeed, a New England gray fox crossed the border in New Brunswick, entering the Maritimes of Canada for the first time in centuries. 

So if the foxes are thriving in the Northeast and even expanding their range, it is unlikely that simple adversarial relations between red foxes and other carnivora are the answer.

This question is one that must be teased out in the scientific literature, but if gray foxes are going to be part of the native fauna of the region, it must be answered.