Why do squirrels chase each other?

It’s a familiar sight, but what are these energetic chases for?

Squirrels can often be seen chasing each other up trees and along branches. This behaviour can be attributed to one of three factors: dominance, reproduction or fun. Most commonly it’s associated with establishing territories, with rival squirrels chasing each other to assert their dominance and claim a tree or patch of forest. Territorial species include American red squirrels, but this trait is not shared by all species; grey squirrels, for example, often have overlapping home ranges and don’t need to chase away intruders.

Chasing can also be linked to reproduction. Studies have indicated that male squirrels will give chase to determine the reproductive state of a female, indicated through her scent. This behaviour can be witnessed throughout the year, as mating can occur between December and February and between June and August depending on the species of squirrel.

A final explanation is simply that scuttling aft􏰀er each other is fun; juveniles will chase as a form of play-fighting, like the friendly tussles seen in puppies and kittens.