Black squirrels are a melanistic subgroup of squirrels with black coloration on their fur. The phenomenon occurs with several species of squirrels, although it is most frequent with the eastern gray squirrel and the fox squirrel.
Black fur for both species of squirrels is rare, and occurs at rates of less than one per cent. It has been suggested that one in 10,000 eastern gray squirrels are a black morph.