Squirrels rely on birds to let them know when it's safe to go out

September 6, 2019, 8:25 a.m.
A squirrel and a starling sharing a snowy branch.
Photo: KellyNelson/Shutterstock

Never underestimate a squirrel's survival skills.

Gifted acrobats, they trampoline from tree to tree, always a step ahead of danger. They've even been known to gather old rattlesnake skins and rub the scent on their fur to create a kind of predator repellant.

And now, a newly published study in the journal Plos One suggests squirrels rely on social media to figure out when it's safe to leave home: they read tweets.

As in, actual chirps and chatter from songbirds in the neighborhood.

No, for all their incredible abilities, squirrels don't actually speak the language of birds. Rather, researchers from Ohio's Oberlin College suggest, they keep their ears to the ground — and try to get the gist of a conversation.

What's all that chirping about outside, a wary squirrel might ask himself? Did someone just say, "red-tailed hawk?"

Better to curl up in the burrow until things settle down out there.

"This study suggests that eavesdropping on public information about safety is more widespread and broader than we originally thought," study co-author Keith Tarvin tells The Guardian.

Indeed, songbirds don't owe grey squirrels anything. Neither species is dependent on the other, the researchers note, and they move from place independently, But when squirrels happen to have birds as neighbors, they make savvy use of their chatter.

"It may not require tight ecological relationships that allow individuals to carefully learn the cues provided by other species," Tarvin adds.

For the study, researchers looked at a 67 grey squirrels going about their nut-gathering business around the city of Oberlin. After observing them for a period, the team played a short clip of a red-tailed hawk's call. Predictably, the squirrels got really nervous, freezing in place — a typical defense strategy among rodents — and looking up to the sky for signs of dive-bombing death.

Then the scientists played a clip of songbirds chatting normally. And sure enough, the squirrels went back to their foraging ways — as if to say, if it's safe enough for birds, it's safe enough for us.

The findings seem to be in keeping with a squirrel's abiding philosophy of letting others do most of the work for them. By letting birds shoulder all the anxiety of a potential threat, squirrels can focus their energy on their one great obsession: nut acquisition.

"Recognition of bird chatter as a sign of safety is likely adaptive, as squirrels that can safely reduce their vigilance level in the presence of bird chatter presumably are able to increase foraging success," the researchers noted in the study.

Indeed, life in the forest, or even the lone tree in your backyard, isn't all nuts and honey. Snakes, coyotes, hawks and owls are constantly on the prowl for wayward rodents. And constantly fretting about them can be taxing on a squirrel.

Best, it seems, to let birds handle the Neighborhood Watch.