Upside-down Birds

Nuthatches are common birds with uncommon habits. They are the only bird that walks upside-down. And almost everyone can watch this feat in their own back yard.

Nuthatches explore all surfaces of trees -- top, sides and bottom -- searching for seeds and insects. Many of us marvel at their ability to walk down trees -- head first. Why don't they fall? Perching birds characteristically have four toes, three that face forward and one that faces backward. The backward facing toe is akin to our thumb and is called the hallux. Nuthatches have a stronger hallux than most perching birds their size and they use it to grasp the tree at a right angle to the trunk. In addition, they always have at least one foot tightly grasping the tree and keep their feet spaced far apart.

Nuthatches are named for their behavior of wedging a nut into a tight cranny and then pecking at it until it is cracked. Originally called "nuthacking," the name morphed into its present form. To accommodate this behavior, they have developed a stout bill (for pounding) that comes to a point (for probing).

There are two species of nuthatches in Vermont, the White-breasted and Red-breasted. White-breasteds have a white breast as their name suggests and a black crown with white cheeks. Red-breasteds have a rusty colored breast and a black stripe through the eye.

Another important distinction between the species is habitat preference. White-breasteds live year-round in deciduous forests, while Red-breasteds prefer conifer dominated forests. The boreal forest supports 25 percent of the breeding Red-breasted population. This preference for conifer forests leads to an interesting phenomenon called irruption. Roughly every other year the boreal seed crop is low and Red-breasteds migrate south in search of food.

Because winter is such a hard time of year to find food, nuthatches hide seeds and insects in nooks and crannies for later consumption. Instead of finding a few good places to hide masses of food like squirrels and some woodpeckers, they hide just one food item per cache.

Bird feeding is known to help nuthatches maintain their health over the cold winter months, and fortunately for us, both species are common feeder birds in Vermont. They favor suet feeders and sunflower and safflower seeds.

Other sightings

White-winged Crossbills, another irruptive species taking advantage of the heavy cone crop this winter, were confirmed breeding at Moose bog in the Northeast Kingdom last week. Black-backed and Three-toed woodpeckers, Gray Jays, and Boreal Chickadees continue to delight birders in the bog making for an exciting day trip.

Shelburne continues to be a good spot for waterfowl, with the highlights being two Harlequin Ducks, a pair of Lesser Scaup, Hooded Merganser and rafts of goldeneye.