Thursday, April 7, 2011

Brown-headed Nuthatch

Brown-headed Nuthatch - Spec. Name: Sitta Pusilla

Brown-headed Nuthatch
This is a small (approximately 3.5 in/8.9 cm in length) songbird found in pine forests throughout the Southeastern United States. An endangered population occurs in the pineyards of Grand Bahama; some authorities consider it to represent a separate species, S. insularis. The bird, like other nuthatches, possesses a sharp black nail-like beak, which it uses to pound open seeds. It is a frequent visitor to feeding stations and is highly fond of sunflower seeds and suet cakes.

Bold and inquisitive, this bird is readily approachable by humans. The bird is frequently observed using a small chip of bark held in its beak as a tool to dig for insects.

This species of nuthatch sports a brown cap with narrow black eyeline and buff white cheeks, chin, and belly. Its wings are bluish-gray in color. A small white spot is found at the nape of the neck. The bird's call is a sharp whee-hyah sounding very similar to a "rubber duck" toy and particularly is loud for a bird its size. They also make softer "pit pit pit" calls while in flight as well as other squeaking noises.

The Brown-headed and Pygmy Nuthatch are nearly identically in appearance, but have vastly different ranges with the Pygmy being confined to coastal central California. Both have short tails, large heads, and long bills on body lengths of 4.25 inches. They are smaller than the commonly occurring White-breasted Nuthatch. The Brown-headed sports a brownish cap with a large white spot on its nape; the Pygmy's cap is more grayish brown. The Brown-headed Nuthatch gives a high sharp, nasal two-syllable vocalization, often followed by a rapid series of lower nasal notes.

A characteristic bird of the pine forests of the southeastern U.S. The species historically nested as far north as southeastern Missouri but now only occurs as far north as northeastern Texas, middle Tennessee, and eastward into far southern Pennsylvania. Highest breeding densities are in western South Carolina and Georgia, central Florida, and southern Mississippi. Audubon Important Bird Areas (IBA) that support Brown-headed Nuthatch includes North Carolina's Sandhills East IBA and Sandhills West IBA.

Numbers are declining throughout its range. Breeding Bird Surveys in southeastern North America from 1966 through 2001, show a statistically significant annual population decline of 2.2 percent. Populations on Grand Bahama Island are nearly gone, probably due to extensive logging; and southern Florida has also lost substantial numbers of this species.

Almost exclusively breeds in southeastern pine forest habitats; loblolly-shortleaf pines and longleaf-slash pines appear to hold the highest numbers. The bird requires snags (standing dead trees) for nesting and roosting; but forages on live pines. It is more abundant in older pine stands compared with younger stands as well as burned stands. Nesting includes excavating cavities in trees, most commonly between February and April. Incubation lasts two weeks. Young fledge 18 to 19 days. The bird subsists on bark-dwelling cockroaches, beetles, and spiders in the warmer months and various arthropods and pine seeds when it's colder.

This non-migratory species generally does not disperse far from its breeding range; although widespread decline in pine seed crops one season may force birds to extend their range. One of few species of passerines known to use tools; the nuthatch finds loose bark flakes to pry attached flakes where insects are hiding.

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