BIRDS WHO CAN REALLY GET A GRIP!
By Jeannie Marcure
As members of the bird family SITTIDAE, nuthatches are described by this Greek word as birds that peck at the bark of trees. Additionally, the name nuthatch originated in Europe and refers to the foraging technique in which the birds take a seed, fly to a tree branch, jam the seed into a bark crevice and hack or “hatch” it open with the bill. Keeping those facts in mind gives us a good start toward understanding the behavior of these small, rather stocky birds that are often seen scurrying headfirst down tree trunks
Although these little birds bear a superficial resemblance to woodpeckers because of their food choices and gathering methods, they are not closely related and can be distinguished from woodpeckers by their smaller size (from 4.25 inches for the Pygmy to about 6 inches for the White-breasted), their square tails, the upturned underside of the bill, and by their ability to walk down tree trunks supported only by their strong feet and legs. Remember woodpeckers have moveable spines in their tail feathers that allow them to use the tail for support and balance as they climb. Because of the need for this extra support, woodpeckers can only move in an upward direction.
Of the four species of nuthatches found in North America, three are commonly found here in Western Montana: the Pygmy Nuthatch, the Red-breasted Nuthatch and the White-breasted Nuthatch. The Pygmy and White-breasted are predominately gray and white, while the Red-breasted is gray with a rusty, reddish breast and has a distinctive white eyebrow with a black line through the eye. The easiest way for me to differentiate between the Pygmy and White-breasted is by looking at the head and eye. The Pygmy has a dark cap bordered by a slightly darker line that ends just below the eye, while the White-breasted has a dark gray or black cap with white all around the eye and face. Yes, the bird pictured with this article is a Red-breasted—notice the black stripe through the eye.
Nuthatches are monogamous cavity nesters, with White-breasted Nuthatches nesting in existing holes while the other two species normally make their own cavities. Occasionally, nuthatches will use a nest box. We once had a Red-breasted family raised in an east-facing box near our deck and it was delightful to see the mother stick her head and chest out of the hole to enjoy the morning sun! Normally taking one to eight weeks, the nest construction process is shared by both sexes with the female taking the lead. Pygmy Nuthatches travel in small flocks of two to five birds consisting of the mated pair and unmated male relatives who serve as “helpers” during the breeding cycle. The occurrence of these helpers is particularly high where lack of habitat prevents them from breeding themselves. Nest holes are lined with fur, feathers, twigs, bits of bark and vegetation. Red-breasted Nuthatches smear sap around the hole entrance and White-breasted Nuthatches sweep around the nest entrance with noxious smelling insects. Both behaviors help deter predators from entering the nest area. Cavity-nesting birds usually lay pure white eggs but nuthatches are the exception and produce white eggs heavily spotted and streaked with brown. Incubation is primarily the job of the female.
Our nuthatches are non-migratory and frequent visitors at feeders during the winter months. To combat our severe winters, they often roost communally in a single cavity for warmth and records exist of more than 100 birds huddled in a single cavity. For more information about these spunky little birds, check out Cornell’s new online bird guides at:https://www.allaboutbirds.org