Brown-headed Nuthatch Sitta pusilla Scientific name definitions

The Brown-headed Nuthatch is endemic to the pine forests of the southeastern United States and is rarely seen far from pine-dominated areas. It is also one of the few cooperatively-breeding birds native to North America, and one of the few for which tool use has been documented (individuals use chips of pine bark to pry off other bark chips while foraging).

This nuthatch's habit of staying high in the canopy often makes it difficult to observe, but its tendency to nest lower has encouraged studies of its breeding biology. Norris's (1 Norris, R. A. (1958b). Comparative biosystematics and life history of the nuthatches Sitta pygmaea and Sitta pusilla. University of California Publications in Zoology 56:119-300. Close ) pioneering work detailed the breeding biology of a Georgia population of the Brown-headed Nuthatch as part of a comparative study with its sister species, the Pygmy Nuthatch (Sitta pygmaea). Many aspects of Brown-headed Nuthatch biology, including its cooperative breeding behavior and its population demography, have recently been investigated in color-marked populations, providing a wealth of information upon which to base further study.

The Brown-headed Nuthatch's association with pines, particularly mature pines, and its reliance on snags for nesting likely make it an important indicator species for the health of southeastern pine forests, which have been extensively logged over the last century. This species' failure to recolonize areas where extirpated due to habitat change highlights its vulnerability, but it is also one of the few North American landbirds that has been successfully reintroduced to the habitat it formerly occupied. The threat to the Brown-headed Nuthatch, however, is poignantly demonstrated by the possible extinction of its sister species, the Bahama Nuthatch (Sitta insularis), which had an estimated population of only 2 to 6 individuals in 2018 (2 Karikehalli, S. (2018). The Bahama Nuthatch, thought to be lost to hurricanes, is not extinct -- yet. Audubon News. https://www.audubon.org/news/the-bahama-nuthatch-thought-be-lost-hurricanes-not-extinct-yet Close ) prior to the devastation wreaked by Hurricane Dorian in 2019. The Bahama Nuthatch and Brown-headed Nuthatch were formerly considered conspecific (3 American Ornithologists' Union (1983) Check-list of North American Birds. Sixth edition. American Ornithologists' Union, Washington, DC, USA. Close ), but the Bahama Nuthatch was recognized as a distinct species in 2021 (4 Chesser, R. T., S .M. Billerman, K. J. Burns, C. Cicero, J. L. Dunn, B. E. Hernández-Baños, A. W. Kratter, I. J. Lovette, N. A. Mason, P. C. Rasmussen, J. V. Remsen Jr., D. F. Stotz, and K. Winker (2021). Sixty-second supplement to the American Ornithological Society's Check-list of North American Birds. Auk 138:ukab037. Close ) based, in part, on differences in vocalizations (5 Hayes, W.K., Barry, R.X., McKenzie, Z. and Barry, P. (2004). Grand Bahama’s Brown-headed Nuthatch: a distinct and endangered species. Bahamas J. Sci. 12(1): 21–28. Close , 6 Boesman, P., and N. J. Collar (2020). Further vocal evidence for treating the Bahama Nuthatch Sitta (pusilla) insularis as a species. Bulletin of the British Ornithologists’ Club 140:393–403. Close ) and responses to playback (7 Levy, H. E., and J. A. Cox (2020). Variation in responses to interspecific vocalizations among sister taxa of the Sittidae: Imminent extinction of a cryptic species on Grand Bahama Island? Avian Conservation and Ecology 15:15. Close ).