Q: I recently saw a gray squirrel with black fur. How rare are they?
A: Good question! I don’t know how rare they are.
They are a color variation that is not as well adapted to typical squirrel habitat and life in the wild. However, under the right circumstances and in some locations (probably where predators are less prevalent) they can survive well.
There are certain locations, usually small towns and cities, where they are relatively common and where there appears to be a strong component of the genes for that color variation in the squirrel population.
I grew up in a small town that had another variation quite commonly. We had white squirrels.