One backyard bird that’s pure fun to watch is the white-breasted nuthatch.

This animated, year-round songbird, recognized easily by its black head cap, has a series of loud nasal calls. One sounds like, “Yank, Yank,” and can be heard two blocks away. The white-breasted nuthatch is also nicknamed the “upside down bird,” because it often spirals down tree trunks headfirst, hunting for insects hidden in the crevices of tree bark.

How can nuthatches go headfirst down a tree trunk without falling?

The answer is in their toes. Woodpeckers have two toes in the front of their feet and two in the rear, allowing them to move up the tree trunk, while nuthatches have three toes in the front and one in the back, enabling them to firmly grip the bark and travel “upside down.”

Nuthatches get their name from wedging seeds and nuts, like sunflower seeds, small acorns or beech nuts in the chinks of tree bark and “hacking” or hammering them open with their sharp, toothpick-like beaks.

These cute little birds don’t seem to mind people, either.

For example, I’ve sat quietly in a chair, outside, five feet from my bird feeder, and had nuthatches fly in and take black oil sunflower seeds from the feeder without any hesitation. The intrepid little chickadees will do the same.

My grandfather did one better. In his 80s, he used to sit in a chair in his backyard, wrapped in a blanket, and have chickadees and nuthatches fly in and eat birdseed out of his hand. When I first saw this magical sight, I was so impressed, I thought my grandfather was St. Francis of Assisi. One memorable Christmas, when I was 7 years old, he gave me a subscription to “Audubon Magazine,” and I’ve been hooked on birds ever since.

Others have found white-breasted nuthatches entertaining, too.

In 1822, for example, the gifted John James Audubon painted four white-breasted nuthatches on a tree limb and later wrote in his journal, “The nuthatch moves alertly…climbing or retrograding downwards or sidewise, with cheerfulness and a degree of liveliness, which distinguishes it from other birds.”

Elsewhere, in 1948, Arthur Cleveland Bent profiled the white-breasted nuthatch in the Smithsonian Institute’s National Museum Bulletin, writing, “He is short-necked, broad-shouldered, sturdy, quick and sure in his motions, suggesting an athlete.”

Bent’s quote reminded me of a time when I saw a white-breasted nuthatch take a sunflower seed from my feeder, fly to a tree, then accidentally drop it.

Like a bullet, the nuthatch flew straight down the trunk of the tree to catch the tiny seed in mid-air with its beak, inches from the ground. I was amazed at the quickness and agility of this bird.

“Of all the regulars at your bird feeder, in winter or summer, nuthatches are the ones that are just a tad quirky,” writes Gustave Axelson for the Cornell Lab of Ornithology’s All About Birds web site. “They move differently than other birds, scaling the trunks of nearby trees up, down, and sideways with the erratic motion of a wind-up toy.”

There are three different types of nuthatches in North America. They are: the brown-headed nuthatch, found in the southern pinelands; the red-breasted nuthatch, a dweller of the conifer forests of the upper Midwest, New England and southern Canada, and the white-breasted nuthatch, the largest of the three, commonly found throughout the eastern half of the United States.

The good news is white-breasted nuthatches are common to our Connecticut backyards, and are easy to attract to our feeders with suet or black oil sunflower seeds.

Bill Hobbs lives in Stonington.