What is a white squirrel?

The white squirrel seen in the United States is an albino or white morph of the eastern gray squirrel. Albinism is caused by a mutation of the gene responsible for pigmentation, while the white morph is the product of the aberration of a different gene.

While naturally occurring, both albinism and white morph squirrels are extremely rare. Since albinism also results in a lack of eye pigment, albinos are distinguishable from white morphs by their red eyes. Natural selection also plays a factor in the small population size of white squirrels, as predators are drawn to the white coat that makes them stand out from their surroundings.