Straneck's Tyrannulet Serpophaga griseicapilla

Small flycatcher with a gray head, an olive-brown back, a whitish throat, and a yellow belly. Note the white eyebrow and broken eye-ring. Occurs in woodland and scrub; migrates to the northeast during the austral winter. The song is a single note followed by a trill: “twie tirrrrrrrrrrrrrrrrrr.” The similar White-crested Tyrannulet has a different song and is also slightly larger, with a white crown patch that is often concealed.