White tailed Gray Squirrel

A gray squirrel with a snow white tail was recently spotted in an area not far from the Walkersville Watershed. It seems that this kind of generic aberration is fairly rare, especially in animals spotted in less populated areas. A squirrel having this marking would be at a terrific disadvantage in an area where predators are plentiful.  Obviously, waving a white flag around hunting hawks, for example, would be very dangerous.

Credit: flickr.com
Credit: Claude Eans, Board member

Gray squirrels come in many colors, most commonly shades of gray, and less commonly, shades of brown. There are also pure white and pure black squirrels, but both are variations of the gray squirrel. The color variation can come from a recessive trait that will occasionally appear in the genetic line. The mother having a white tail will pass that characteristic to her offspring.

Unusual squirrel color variations are less rare. They can turn up in any population.  They are most likely related to the same types of genetic variants that can lead to the white albino and dark black melanistic squirrels. Black squirrels are often found living in colonies in residential areas. 

Inheritance of color involves many genes, and these can be modified by environmental factors. It is more common to see these partially odd-colored variations in city parks, for example.  These types of anomalies would be more common in suburban and urban areas, where inbreeding can occur as the populations become more isolated due to environmental conditions like roads and other human created barriers.

Article by Claude Eans, FCFCDB member

Nature Note for 6/10/2018