Why Squirrels Turn Aggressive — and How California Homeowners Can Respond Without Poison

A Marin County neighborhood spent the past week on alert after a string of squirrel attacks. In Lucas Valley-Marinwood, just north of San Rafael, an unusually aggressive squirrel bit several residents, sending some to the emergency room and leaving neighbors hesitant to go outside.

The behavior behind these attacks is not mysterious, and understanding it points every California homeowner toward the right way to handle squirrels on their property.

Why a squirrel becomes aggressive

Wild squirrels normally keep their distance. When one starts approaching people, something has changed that behavior — and it is almost always human.

According to the Marin Humane Society, the Lucas Valley-Marinwood squirrel's boldness may be tied to hand-feeding. When people feed wild animals, the animals learn to associate people with food and lose their natural wariness. Wildlife experts have warned for years that feeding wildlife increases contact between people and animals, and that contact is what raises the odds of an aggressive encounter.

Officials are also looking at whether the squirrel was defending a nearby nest. Squirrels protect their young, and getting too close during nesting season can be enough to provoke an attack.

One point worth settling: none of the injured residents needed treatment for rabies. Squirrels almost never carry it, and there are no known cases of a person in the United States contracting rabies from a squirrel.

What to do if a squirrel is acting aggressive

The guidance from Marin County officials is direct. Do not hand-feed squirrels or other wildlife. Give any animal behaving strangely a wide berth, and keep children and pets away from it. Report unusual behavior to local wildlife officials rather than trying to handle or remove the animal yourself.

Wildlife officials and the Marin Humane Society have posted warning signs in the affected neighborhood, and residents had started putting up their own notices before the official response arrived.

The real problem: squirrels that establish themselves

Most squirrel complaints never involve a bite. But they share a root cause with the Marin County case: a squirrel finds a reason to stay close, settles in, and becomes difficult to move along. Once a squirrel is established on a property, it stops being an occasional visitor and starts being a resident.

That is the problem homeowners actually need to solve, and how you solve it matters.

Rodenticides are the wrong tool. Poison puts children, pets, and the wildlife you want to protect at risk of secondary poisoning, and it does nothing about the squirrels actively coming onto your property.

There is a poison-free way to manage squirrels. The Automatic Trap Company is the North American distributor of the A18, a trap manufactured by Goodnature that uses no toxin of any kind. It is CO2-powered and self-resetting, so once established, it works around the clock. 

Learn more about the A18 Squirrel Trap Kit here.