Technically speaking, the white squirrel that has been spotted around campus of late is not an albino squirrel, says Tim Stewart, associate professor in natural resource ecology and management. The fur of an albino squirrel would be entirely white, and the animal would have pink eyes.
"This squirrel is not entirely white, has dark eyes, and is therefore referred to as a 'leucistic' individual, simply meaning that it has lighter-colored fur than typical members of its species," Stewart explained. "As with albino squirrels, there are rare genes in the squirrel population that occasionally result in an individual with fur color that is different than the typical individual."
For this little fox squirrel (Sciurus niger), typical would be orange-brown coloring. As with albinism, leucism probably isn't advantageous in avoiding predators in most situations, Stewart said. This is a likely the reason leucistic individuals are not more common in the squirrel population.