Squirrels possess sharp, curved claws, which are specialized adaptations for their arboreal lifestyle. These claws are found on tree squirrels, such as the Eastern Gray and Fox squirrels, which spend much of their lives moving through the forest canopy. Squirrels rely on this anatomy to navigate their environment. They use these appendages for various survival behaviors beyond just climbing.
The Physical Structure of Squirrel Claws
The sharpness of a squirrel’s claw results from its composition and shape, typical of many climbing mammals. Each claw is formed from keratin, a tough, fibrous protein that provides the strength and rigidity needed to support the animal’s weight. The claws exhibit a distinct, highly curved, hooked shape. This shape functions as a grappling tool, allowing them to instantly catch and hold onto surface irregularities.
The claws are non-retractable, meaning they are permanently exposed to provide immediate traction, unlike a domestic cat’s retractable claws. This fixed position is paired with a unique skeletal feature in the hind limbs. Squirrels can rotate their ankles 180 degrees, enabling them to point their rear feet backward. This rotation allows the curved claws of the hind feet to hook into the bark while descending a tree trunk headfirst.
Essential Functions of the Claws
The primary function of the sharp claws is to facilitate the rapid and secure movement necessary for survival. The hooked structure allows squirrels to generate high-traction grip on rough surfaces like tree bark. This enables them to ascend and descend trees quickly to evade predators. This secure hold is maintained even during the acrobatic leaps they perform between branches.
Foraging behavior also relies heavily on the claws, particularly for scatter-hoarding species. Squirrels use their forepaws to quickly excavate shallow pits in the soil to bury a single nut or seed. After depositing the food, they use their paws to tamp the item into place and cover the cache, concealing it from competitors. The sharp claws are also utilized for manipulating food items, such as securely grabbing and rotating hard-shelled nuts while gnawing through the exterior.
Practical Considerations for Homeowners
While sharp claws are a biological necessity in the wild, they can cause damage when squirrels enter human structures. The claws allow the animals to climb virtually any textured vertical surface, including stucco, brick, and rough siding, while searching for entry points. Once inside an attic or wall void, the claws contribute to the destruction of soft building materials.
Squirrels tear and shred materials like fiberglass or cellulose insulation to create a warm, secure nest. This clawing action reduces the insulation’s thermal effectiveness and creates pathways within the home. If a squirrel is cornered or handled, its sharp claws and teeth become a primary means of self-defense. This results in painful scratches as the animal attempts to escape.