Gray foxes, one of only two species surviving in their genus, have been declining in one specific part of their range – the Southeastern US – for decades. A new study published in the Journal of Mammology takes a closer look at why.
Coyotes are also native to the United States but historically lived in the western to midwestern states. Recently, coyotes have moved eastward, coinciding with the decline in foxes.
Study co-author James Beasley of the University of Georgia explained how looking at trapping records inspired the research.
“Here on the Savannah River Site, there are excellent historical trapping records and gray foxes used to be really abundant. But now we don’t see them nearly as frequently. That’s prompted questions of why – why are we seeing the reduction in these numbers?”
The records showed that as the populations of gray foxes decreased, the populations of coyotes in the area increased. The scientists knew that coyotes and gray foxes co-existed well in other parts of their range, so they began to wonder if something was different in the southeastern populations. The researchers compared the diets of foxes and coyotes in both places by chemically analysing hair from the animals.
“In the Midwest, we found there were significant differences in diet between species, whereas in the Southeast they overlapped significantly,” explained study lead author and doctoral student Sarah Webster.
The study reveals that, in the Midwest, coyotes and gray foxes had time to find their own specific niches, partitioning their use of food to avoid competition with each other. Not enough time has passed in the Southeast for this process to take place yet. The question the scientists ask is, will the coyotes and foxes sort out their competition for food before it’s too late?
It seems that the behavior of gray foxes is changing slightly, possibly a good sign that they’re adapting to coyotes. The scientists point out that there is no evidence that we’re capable of effectively controlling coyotes anyway. Perhaps the best we can do is support good environments for gray foxes and let nature take its course.