Audubon's warbler

The Audubon's warbler (Setophaga auduboni or Setophaga coronata auduboni) is a small New World warbler.

This passerine bird was long known to be closely related to its eastern counterpart, the myrtle warbler, and at various times the two forms have been classed as separate species or grouped as the yellow-rumped warbler, Setophaga coronata. The two forms probably diverged when the eastern and western populations were separated in the last ice age.