Why Do Squirrels Always Chase Each Other?

• Adult squirrels engage in chases to establish order, mate, and protect territory.
• Younger squirrels usually chase each other to play-fight, improving their coordination and strength.
• Squirrels rarely fight to the death, but adult squirrels engage in aggressive behavior–biting, scratching, screeching–to protect their territory and food supplies.

Why do squirrels chase each other?

Establishing order When you see squirrels chasing each other, it’s usually a male showing dominance to another male. Most squirrel colonies establish a pecking order based on age, size, and gender. Older, larger males generally dominate the entire group, but females are more dominant when they have litters. Among males, social hierarchies determine mating arrangements and settle territorial disputes.

Mating During the breeding season (winter and spring), male squirrels smell hormonal changes in females, triggering the mating ritual. Males first chase each other to establish dominance. Then, the dominant male slowly chases the female until she agrees to mate. Females squirrels hide if they’re uninterested in mating with the dominant male. Or, they keep running away until the male tires and finds another partner. Some non-dominant squirrels attack the dominant male in front of the female, stealing the mating opportunity from him. Male squirrels make a soft "muk" or "quaa" noise when chasing a mate, similar to a chicken's cluck.

Protecting territory Due to the high density of squirrels in some habitats, there is often significant overlap in territory. Squirrels are highly protective of their burrows because it protects them from predators, so if you see an aggressive chase, followed by a bite, it may be a sign of a territorial dispute. Older, dominant squirrels are known to bite other squirrels invading their space, but females also show aggression if there are limited nesting sites to raise their young. Squirrels rub their scent glands and urine on branches and trunks to mark their territory. Most squirrels claim a half-acre to one acre of land, but some species claim up to 25 acres.

Protecting food supplies During the winter, squirrels rely on stored nuts and seeds for survival, which they bury in areas surrounding their nests. Squirrels aren’t afraid to protect their stash from others looking to steal, but aggressive tactics only come into play in areas where food supply is limited. If a squirrel rapidly flicks its tail and makes a rolled chirping noise, interpret it as a sign to back off–you may be approaching its food supply or territory. Many squirrels build several nests: some for sleeping, some for feeding, some for storing, and some for guarding their territory.

Play-fighting Young squirrels are known to chase each other for fun, but playing tag also has its benefits: chasing is incredibly useful in improving coordination, strength, and overall survival skills. Most young squirrels outgrow this behavior as they transition into adulthood, but some squirrels still enjoy playing around.

Do squirrels hurt one another during chases?

Younger squirrels don’t hurt each other, but older squirrels harm intruders. When juvenile squirrels play-fight, there’s no biting or serious harm. Older squirrels, however, aren’t as playful; they nip, scratch, and screech at other squirrels, especially during territorial disputes or mating season. Squirrels rarely fight to the death, but there are cases of squirrels attacking and killing others over territory or food supplies. If you see two smaller, immature squirrels chasing each other, it’s probably just for fun; adults are likely mating or establishing dominance.

Do all squirrels chase each other?

Gray squirrels don’t engage in chases often. Gray squirrels aren’t territorial, so they’re not likely to chase or attack other squirrels; they live comfortably beside humans in urban areas and are highly social and adaptable creatures. Red squirrels are particularly aggressive toward other squirrels, including members of their own colony, and they’re highly likely to chase intruders. Typically, young squirrels only chase other young squirrels; adults are busy foraging for food and protecting their territories.