Under parts mostly rust colored; top of head black; black eye stripe; sides and bottom of head white; back and wings variable charcoal gray. 11 cm (4.5 in) in length. The call of this species is a high-pitched, nasal yank. All of the birds in this family are commonly seen climbing up, down, and around tree trunks and branches.
The breeding season begins in mid-May and extends to mid-June. Preferred nesting habitat is conifer or mixed conifer forest. The nest is commonly 1.5-12 m (5-40 feet) high. This adaptable species nests in a naturally occurring cavity, excavates its own cavity, uses an abandoned woodpecker cavity, or occasionally uses nest boxes. The female lays 4-7 (usually 5-6) eggs that she incubates for 12 days. The male feeds the incubating female. The young are altricial and fledge 14-21 days after hatching. The juveniles are fed for a short period after leaving the nest.
Spruce-fir forests are the preferred habitat of this nuthatch, but other coniferous forests may also fill this requirement. The diet of this nuthatch includes mostly insects and spiders, although during the winter some conifer seeds may be eaten. The food is found by searching the trunks and branches of trees.
The Red-breasted Nuthatch occurs mostly in upper elevations throughout the United States all year. In the winter it occupies most of the middle and eastern portions of the country. In the Southeast, this nuthatch is uncommon in the lower elevations during the winter. The only breeding area in the Southeast is found in the southern Appalachians.
This species is fairly common in appropriate habitat and is not listed as Threatened or Endangered in any part of its southeastern range.
The most similar species are the White-breasted Nuthatch and the Brown-headed Nuthatch. The White-breasted Nuthatch differs in appearance by lacking the black eye stripe and being mostly white underneath, except for a rusty wash near the rump. The Brown-headed Nuthatch has a brown head and lacks the black eye stripe.