Why Does a Grey Squirrel Turn White?
In this article I will talk about Leucistic mutations, which are caused by a change in the melanocytes of a grey squirrel. Leucistic mutations affect the eastern grey squirrel, and these white mutants are also known as leucistic. The reason behind their unusual coloration is not completely understood, but we can speculate a bit. In these cases, the melanocytes do not work properly, and they’re not affected by UV light.
Table of Contents
Melanocytes don’t work
The melanin gene in the gray squirrel has been found to be different in some individuals than in others. These mutations can occur in the melanocytes or in their receptors. This can be a recessive mutation or a condition where one gene in each parent is normal but the other one is not. Rarely, a squirrel will develop true albinism. These animals may have reduced vision or increased risk of falling. Currently, the cause of the decreasing population of albinos in the Olney Illinois area is unknown, but it is suspected to be linked to cats.
The genetic patterns of grey squirrel populations in the UK support the hypothesis that humans might be responsible for this long jump invasion. These results, published in Biological Conservation and Diversity and Distributions, confirm that the long jump invasion mechanism was mediated by humans. The authors of this paper state that it is the result of a combination of human-induced genetic and environmental factors. The research also provides a possible mechanism for grey squirrel conservation.
UV light doesn’t affect melanocytes
Scientists have been wondering if UV light may contribute to skin cancer in grey squirrels. They hypothesize that UV radiation may have an indirect effect on melanin production in grey squirrels by inhibiting a protein and RNA called rhodopsin. If so, the melanocytes are not exporting melanin to other cells of the skin, preventing them from tan.
It is thought that the XP gene family is responsible for the UV-induced melanin pigmentation in humans. The XP gene family encodes a-MSH, the most important melanocortin in humans. It also activates the MC1R, a gene that stabilizes the PTEN enzyme, and it induces the synthesis of a-MSH, the main melanocortin. The p53 and p21 genes are also activated by UV exposure.
Leucistic mutations occur in eastern grey squirrels
Leucistic mutations in eastern grey squirrels have been observed since 1968. These squirrels lack melanin and have white fur and eyes. They may be more aggressive than the wild-type. In addition, black morphs have different densities of fur and may appear larger. Some researchers also found a link between melanism and the black morph’s increased levels of testosterone. A new study by biologists from the State University of New York investigated the behaviour of black and wild-type Grey squirrels.
The genetics of coat colour in squirrels was studied by Herbert Wiltafsky during his Ph.D. thesis at the University of Koln in the early 1970s. He found that lower leg fur colour was determined by a single gene and did not vary with the colour of the tail or back. These findings suggest that some genes may be responsible for the differences in fur colour in eastern grey squirrels.
Melanocytes are rearranged in white mutants
White-coloured mutants of grey squirrel are caused by a mutation in their melanocytes. Although they have no leucistic or albino genes, they do have a gene that promotes phaeomelanin production. As a result, they are white. However, some white mutants also exhibit a paler-than-white colour. Some of these animals are also called white mice.
In addition to the gray squirrel, fox squirrels also have a melanic colour group. The two melanic species share a common ancestor. In this case, the gene MC1R is likely to have arisen in the common ancestor of both species. However, balancing selection would not keep both haplotypes. Moreover, mutation is unlikely to have occurred independently in both haplotypes, as both MC1R and MC2R were found in the same gene sequence.
Food in the mulch is the main source of food for a white squirrel
White squirrels are actually leucistic, which means they are born without the genes to develop a black color. The color of a squirrel’s hair depends on the amount of melanin in its hair cells. A squirrel with too little melanin is white, while a squirrel with moderate amounts is blond. While some white squirrel colonies are short-lived, the Olney, Ill., colony has been around since the 1800s.
While the white squirrel will eat just about anything, there are some things they’ll avoid eating. Some flower bulbs are toxic to them, including snowdrops, hyacinth, and daffodil. Other foods that squirrels won’t eat include chili, although it’s safe for birds. You can even sprinkle chili to keep the squirrels away from bird feeders. Raw onion and garlic are also bad for squirrels.
What is the main difference between a grey squirrel and a white squirrel?
The main difference between a grey squirrel and a white squirrel is their fur color.
Grey squirrels have grey fur while white squirrels have white fur.
Where do white squirrels live?
White squirrels are found in North America Europe and Asia.
Are white squirrels albino?
No white squirrels are not albino.
Albinism is a disorder that is characterized by the complete or partial absence of pigment in the skin hair and eyes.
Why do some grey squirrels turn white?
Some grey squirrels turn white due to a genetic mutation.
Do all white squirrels have blue eyes?
No not all white squirrels have blue eyes.
How can you tell a white squirrel apart from a grey squirrel?
Aside from their fur color white squirrels are generally smaller in size than grey squirrels.
What do white squirrels eat?
White squirrels eat the same things as grey squirrels-nuts seeds fruits buds and insects.
Are white squirrels friendly?
White squirrels are no more or less friendly than grey squirrels.
How long do white squirrels live?
The average lifespan of a white squirrel is 7-10 years.
Do white squirrels mate with grey squirrels?
Yes white squirrels sometimes mate with grey squirrels.
How many offspring do white squirrels have?
White squirrels typically have 2-5 offspring.
What is the scientific name for a white squirrel?
The scientific name for a white squirrel is Sciurus Carolinensis.
What is the scientific name for a grey squirrel?
The scientific name for a grey squirrel is Sciurus Carolinensis.
Are white squirrels endangered?
No white squirrels are not endangered.
What is the most common type of white squirrel?
The most common type of white squirrel is the Eastern white squirrel.

Jessica Watson is a PHD holder from the University of Washington. She studied behavior and interaction between squirrels and has presented her research in several wildlife conferences including TWS Annual Conference in Winnipeg.