Cool Critters: The red-breasted nuthatch is no Chicken Little

No one likes to get duped by fake news, including the red-breasted nuthatch. A year-round resident of the Inland Northwest, this quirky little bird does its best to verify information before retweeting it to other nuthatches.

You’ve probably seen these energetic songbirds in your yard or neighborhood park, moving headfirst down trees like small wind-up toys as they forage for nuts and seeds lodged in the bark. And you’ve no doubt heard their nasal “ank-ank-ank” calls in treetops, reminiscent of successive blows on a child’s tin horn.

This time of year, the red-breasted nuthatch hangs out in flocks with black-capped chickadees, another small songbird. Nuthatches eavesdrop on them, carefully analyzing their calls before passing the information through a network of nuthatches in neighborhoods, fields or forests.

“Nuthatches don’t immediately trust everything they hear,” said bird behavior expert Erick Greene, professor emeritus of ecology at the University of Montana. “Not wanting to over-react or under-react to alert calls given by chickadees, they assess the information before spreading it.”

In two separate studies, Greene and his colleagues found that the red-breasted nuthatch understands alarm calls given by chickadees when predators are nearby. And the first thing they do is factcheck.

“When nuthatches hear chickadee alarm calls, they fly to the top of trees, sit and keep listening,” said Greene, whose most recent findings were published in the journal Nature Communications in 2020. Then, “based on cues encoded in the chickadees’ warning calls, the nuthatches vary their own alarm call according to whether the threat level is high or low,” he explained.

For example, a sharp-shinned hawk perched on a fencepost poses a greater threat to nuthatches clustered in a pine tree than a fox slinking through the snow below.

Three primary nuthatch species live in our region, according to the Washington Department of Fish and Wildlife, with the red-breasted being the most common and widespread. You might see them at your backyard feeder, puffing up their bodies and fanning their wings to get larger birds out of their way.

So why do they flock with the black-capped chickadee?

Both species are small, share the same habitats and are attacked by the same predators, according to an earlier study published in the Proceedings of the National Academy of Sciences, which Greene co-authored. Once nuthatches confirm a chickadee alarm that a high-threat predator is nearby – a pygmy owl, for instance – they typically respond by forming a large angry mob and driving it off. Strength in numbers.

“It’s a survival tactic that benefits both the nuthatches and the chickadees,” Greene said.

But it’s not a tactic used year-round. As temperatures start to warm, the two species will break away from winter flocking to establish their breeding territories. Come fall, they’ll join forces again.

As for the red-breasted nuthatch’s tried-and-true approach of verifying information before spreading it?

“We humans could learn something from them,” Greene said.