What Does “A Colony of Squirrels” Mean?
“Colony” fits some squirrel species considerably better than others. Tree squirrels, the most familiar backyard and park variety, are largely solitary outside of breeding and rearing young, making a true “colony” fairly uncommon among them. Ground squirrels, however, including several species found across North America, are genuinely social and colonial, living in interconnected burrow systems shared among related individuals, not unlike a small-scale version of a prairie dog town.
These ground squirrel colonies rely on cooperative vigilance for survival, with individuals taking turns watching for predators like hawks and coyotes and issuing distinct alarm calls that can vary depending on whether the threat is approaching from the air or the ground, a system that lets the whole colony respond appropriately and quickly. “Colony” is really the more behaviorally accurate term for these ground-dwelling, highly social squirrel species than for the more independent tree squirrels most people picture first.
Example: “A colony of ground squirrels had taken over the entire hillside, burrow entrances dotting the slope every few feet.”
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