Nuthatches are small birds in the family Sittidae that go down trees head first.  The Pigmy Nuthatch (Sitta pygmaea)  has a discontinuous range in the west from Mexico to Canada, usually in association with Conifers.

The Brown-headed Nuthatch (Sitta pusilla) is associated with pine forests in the southeastern US and is endemic to the country.  Along with the Pigmy, these are the two smallest nuthatches in the world.