Squirrels are cute little rodents, that belong to the family Sciuridae, which consists of genera Sciurus and Tamiasciurus. Different types of squirrels can be found across the globe. Studies show that there are around 250 types of squirrels on the Earth. While the fox squirrel, western gray squirrel, Douglas squirrel, American red squirrel, and the eastern gray squirrel, can be commonly found in the United States and Canada; the red squirrel or Eurasian red squirrel can be widely seen across the European region. Most of these squirrel species differ in color, size, and some physical features. Among them, there are some truly interesting types, like the albino squirrels, which are sometimes referred to as white squirrels.
Squirrels with Black or White Coat
As mentioned above, certain types of squirrels look different from the regular ones, due to the color of their fur coat. They include black squirrels with jet black fur and white squirrels with a pure white coat. Black squirrels are melanistic variants of the eastern gray squirrels. White squirrels can be variants of any of the ornamental tree squirrels, called Callosciurus finlaysoni, which are found in some parts of Thailand and South East Asia. Such variants are rare and are found in the above mentioned regions only. White squirrels, if sighted in other parts, can be color variants of any of the existing squirrel species.
What Causes Color Variants?
There is no particular squirrel species, with a plain black or white fur coat. The change in the color of fur is caused by variations in production of melanin. The amount of melanin in the fur, determines the body color of the animal. You might have noticed that different members of the same species exhibit slightly different skin or fur color. This is because of the genes that determine the pattern and control of melanin production. So, any change in these genes can affect the body or fur color of the animal. The same applies to squirrels too.
Genetic changes that cause excess production of melanin in normal squirrels result in black squirrels; whereas a reduction in the melanin production results in a white fur coat, and squirrels with such fur coats are called white squirrels.
White Squirrels vs. Albino Squirrels
Now, it is clear that it is the amount of melanin that determines the fur color; and genetic changes may sometimes result in black or white squirrels. However, such squirrels are not common, because such genetic changes are rare. This results in occasional sighting of some white squirrels. In fact, most of the white squirrels are not albino squirrels, but are those squirrels, who have a white fur coat, due to leucism; which is caused by a recessive gene found in certain eastern gray squirrels.
In such cases, these white squirrels have dark-colored eyes, which cannot be seen in albinos, which have a white fur coat; but have pink or blue eyes, due to a genetic condition called albinism. This is a rare condition, when compared to leucism in white squirrels. So, the basic difference between white and albino squirrels lies in their eye color. While albinos have pink or blue eyes, white ones have dark-colored eyes. In case of albinos, the absence of melanin in the eyes affects their vision and impaired vision results in falls and injuries, that leads to loss of life. This makes it very rare to find a true albino squirrel.
In short, most of the white squirrels are not albinos, but both terms are used interchangeably. In order to be an albino squirrel, the fur color has to be white, and the eyes must be blue or pink.