The Slaty Spinetail or Slaty Castlebuilder, Synallaxis brachyura, breeds in the tropical New World from northern Honduras to western Ecuador. It is a member of the South American bird family Furnariida, a group in which many species build elaborate clay nests, giving rise to the English name for the family of "ovenbirds". Slaty Spinetail constructs a bulky spherical stick nest 36x43 cm in size, with a long tubular entrance, in a shrub or vine covered tree. The plumage is mainly dark grey-brown becoming dark grey on the head. The crown and shoulder patches are a rich rufous color. It may be located by its hard chu-chu-chrrrr call.
This photo was taken at Arenal Observatory, Costa Rica.