When backyard squirrels exhibit patches of missing fur, it can be a noticeable and sometimes concerning sight. This phenomenon often stems from identifiable biological and environmental factors. This article explores the primary reasons why squirrels might lose their fur, shedding light on the conditions that affect these common animals.
Parasitic Infestations
Parasitic infestations, particularly those caused by microscopic mites, are a frequent cause of fur loss in squirrels. These tiny organisms burrow into a squirrel’s skin, leading to mange. Two common types are sarcoptic mange and notoedric mange, the latter being highly specific to squirrels.
Mite infestations trigger intense itching, prompting squirrels to scratch excessively, which directly contributes to hair loss. Affected areas often show large patches of fur missing, along with thickened and darkened skin. In cases of sarcoptic mange, secondary bacterial infections can lead to scabbing and crusts on the skin. Severe cases can result in widespread fur loss, making it difficult for squirrels to regulate body temperature, and can lead to emaciation or death. Mites spread through direct contact between squirrels or by contact with contaminated nests and burrows.
Fungal Infections
Fungal infections are another common cause of fur loss in squirrels, with ringworm being a common example. Despite its name, ringworm is caused by a fungus, not a worm, and thrives in warm, moist conditions. This infection attacks the hair shaft, making the fur brittle and prone to breaking off at the skin surface.
Squirrels affected by ringworm develop circular patches of hair loss. The skin in these areas may appear scaly, and while it might look bald, a fine stubble of short hairs often remains. Fungal infections are contracted through direct contact with an infected animal or from contaminated environmental surfaces. Many squirrels can develop an immune response to these infections and recover, with their fur eventually growing back.
Other Contributing Factors
Beyond parasites and fungi, several other factors can contribute to fur loss in squirrels. Nutritional deficiencies can impact fur quality and density. A diet lacking essential nutrients can lead to dull, brittle fur and patchy hair loss. Poor nutrition can also weaken a squirrel’s overall health, making it more susceptible to infections.
Environmental stressors also play a role. Conditions such as overcrowding or extreme weather can compromise a squirrel’s immune system, increasing its vulnerability to diseases that cause fur loss. Stress itself can lead to behavioral changes, such as self-induced fur pulling. Mother squirrels may intentionally pull out their own fur to line their nests, creating a softer and warmer environment for their young.
Localized fur loss can also occur due to physical injuries like scrapes, bites, or other forms of trauma, which can damage hair follicles in specific areas. Some squirrels may have a hereditary condition where hair follicles are non-functional or absent, resulting in naturally bald patches.