The sight of a squirrel stretched flat against a branch or scurrying with a low-slung posture, often called an “army crawl” or “splooting,” is a highly functional and strategic behavior. This distinctive, flattened position is not a sign of injury or surrender. Instead, it serves several immediate biological needs, including avoiding predators and regulating internal body temperature, revealing complex adaptations these small mammals use to thrive.
Concealment and Predator Evasion
The most immediate reason for adopting a low, flattened posture is to minimize the animal’s silhouette against the background. Squirrels are vulnerable to both ground-level predators and aerial threats, such as hawks and owls. By pressing their bodies against a surface, they significantly reduce their visual profile. This minimizes the chance of detection by effectively blending the squirrel’s form with the bark or the ground texture.
Flattening the body also helps conceal the lighter-colored fur of the underbelly, which would otherwise contrast sharply with the darker surface. Their backs typically feature cryptic coloration that camouflages them, making stillness in this low position an immediate defensive tactic. Should a direct attack occur, the posture offers a final layer of defense by presenting the tougher back to the attacker, protecting the soft, vital organs housed in the abdomen.
Thermal Regulation and Cooling Down
When the weather is warm, the “splooting” posture becomes a mechanism for thermal regulation, often termed “heat dumping.” Squirrels lack the ability to sweat efficiently, so they must use environmental resources to cool down. By sprawling out with all four limbs extended, they maximize the surface area of their body in direct contact with a cooler substrate.
The fur on a squirrel’s belly is thinner than on its back, and this area contains superficial blood vessels close to the skin’s surface. When pressed against a cool surface, such as shaded concrete or a branch, heat transfers directly out of the squirrel’s blood into the cooler material through conduction. This strategic heat exchange lowers the animal’s core body temperature, allowing it to continue foraging.
Navigating Tight Spaces and Maintaining Balance
The low-slung, “army crawl” movement is a mechanical necessity when navigating challenging environments. Adopting this low profile lowers the squirrel’s center of gravity, which helps maintain stability across unstable or narrow surfaces. This reduced height is beneficial when traversing thin utility wires, narrow fence tops, or flexible tree limbs.
This flattened movement also allows squirrels to access and move through surprisingly small openings. Due to their flexible skeletons, they can compress their bodies to squeeze into gaps only slightly larger than their heads, sometimes as small as 1.5 inches wide. This enables them to enter small holes in tree hollows or roof eaves for nesting or seeking refuge. When resting on a high, narrow branch, pressing the body flat increases the contact area, securing them against the surface and decreasing the chance of an accidental fall.