White-breasted Nuthatch Is Feathered Fire

By Diane Cooledge Porter
FEATHERED in stone-cold black, grey, and white, the nuthatch is a ball of metabolic fire.

Yenk-yenk-yenk-yenk. A small nasal voice, like a bath toy rapidly squeezed, comes from bare tree branches against a pale November sky. A White-breasted Nuthatch flits to the leafless elm’s trunk and proceeds jerkily downward, head first.

That’s his trademark, hitching around in any direction, as if gravity had no effect on him.

He pauses to chisel loose a bit of bark, finds something interesting. His throat bulges momentarily as he swallows. I can tell this nuthatch is a male, because the top of his head is shiny black. A female’s crown would be gray.

How thick is the White-breasted Nuthatch’s coat?
It’s going to snow. My old down jacket isn’t quite warm enough, and I’m starting to shiver. It doesn’t seem possible for the nuthatch to live outside in such cold. I know he has a warm undercoat, made of small, fluffy feathers next to the skin, hidden beneath the outer contour feathers. I know he can fluff up the downy feathers to increase their insulating power. But still, the bird’s entire body isn’t as wide as the thickness of my coat.

I leave some black oil sunflower seeds on the wooden porch railing and go back in the house. Rubbing my hands together, I watch the nuthatch in the elm from the warm side of my window.

He was waiting for those seeds. One quick swoop brings the nuthatch to the porch. He picks up a seed, drops it, and picks up another. Perhaps this one’s heft or hardness promises a better kernel, and he carries it back to the tree. He lodges the seed into a crevice in the bark, hammers the shell to pieces with his beak, and eats the nutmeat.

Nuthatch. (Hatch means hack, as in hatchet.) One who hacks nuts.

United defense of the White-breasted Nuthatches
Another nuthatch squeaks in the distance. The female and male nuthatches talk to each other like this throughout the winter, but I seldom see them together. If the female is at my feeder when the male comes in for a seed, she flies off before he lands.

In March, however, the two nuthatches will visit my feeders at the same time. The male will pick up a seed and place it in his mate’s beak. For now, they keep their distance.

Yesterday the birds revealed the bond that unites them even in winter. Another male nuthatch happened upon the elm tree. Instantly, the resident pair flew in from different directions and landed on the trunk. Side by side they rushed down the tree toward the intruder. Their short black-and-white tails were spread wide, so that the usually concealed battle-flag pattern showed.

The strange nuthatch departed in haste, and the resident pair drifted apart again. Vigilant protection of their territory is part of the nuthatches’ strategy for surviving winter. Territory is food. Food is life.

Keeping warm

Nuthatches don’t retreat to the tropics each year in the manner of swallows, warblers, and other small birds who must depend all year around on insect food. When cold forces insects to go dormant or even to retreat underground, nuthatches can stay on their home ground and skip the dangers of migration. They change their diet to mostly nuts and seeds, along with the offerings of backyard bird watchers, and devote themselves almost exclusively to food.

It’s food that enables them to generate heat as fast as the weather sucks it away. Feathered in stone-cold black, grey, and white, the nuthatch is a ball of metabolic fire. Its heart beats over 400 times a minute when it’s resting, perhaps three times that fast in flight.

Now the male is back at my porch for another sunflower seed. Yenk! he declares, landing. He’s a study in the horizontal, beak, head, back, and stubby tail all in a line that parallels the railing. A gust of wind ruffles his feathers where wing joins body. I watch the first snowflake blow past him. The nuthatch picks up a seed, and instead of flying off with this one, he lodges it in a nailhead’s depression in the wood and pounds at it with his beak.

Six strokes break the shell. He extracts the kernel, lifts his head, and swallows. I sense his satisfaction. The seed will fuel the fire that warms the nuthatch. Already that tiny flame is warming me.

Metabolism of a small bird in winter
In order to survive frigid nights, a White-breasted Nuthatch can put on fat equal to 10% of its body weight in one day, and burn it off just staying alive until morning.

Imagine a human who weighs 140 pounds in the morning—by nuthatch rules, the scale would read 154 by bedtime. The smaller the bird, the harder it is to stay warm, and the more food it requires for its size.

Because they can walk head-first down a tree, nuthatches get a unique view of the bark and may find hidden food that other birds don’t notice.

Nuthatches are good customers at bird feeders, too. They love oil-rich sunflower seeds and nuts.

Some people say we feed birds primarily for our own pleasure, but the research of Dr. Thomas Grubb, of Ohio State University, shows that White-breasted Nuthatches get through the winter in better nutritional condition if they have access to bird feeders.