Looking like a bit of detached bark spiraling up the tree trunk using its stiff tail for support, this cryptic species searches for spiders and other insects using its curved bill like tweezers. Formerly lumped with the similar Eurasian Treecreeper, genetic and vocal studies have shown that it may actually be more closely related to the Short-toed Treecreeper. Within North America four distinct clades have been identified in which two to four separate species may be recognized in the future. This is the race "Certhia americana phillipsi" which breeds in the Coast Ranges from San Francisco south to San Louis Obispo County. It was described as new to science by Unitt & Rea in 1997 and is characterized by browner belly and smokier dorsal streaks. Sometimes called American Treecreeper, not to be confused with "Mohoua novaeseelandiae" of New Zealand which is also called Brown Creeper.
Reference:
Unitt, P. and A. M. Rea. (1997). "Taxonomy of the Brown Creeper in California." In The era of Allan R. Phillips. A Fest shrift., edited by R. W. Dickerman, 177-185. Albuquerque, NM: R. W. Dickerman.
