Northern schiffornis Schiffornis veraepacis

Elusive, chunky brown bird of shady forest understory in humid tropical lowlands. Heard far more often than seen. Haunting, slurred whistle carries well and is easily imitated. Song given irregularly; not steadily repeated. Note the chunky build, drab dark olive-brown plumage with paler eyering accentuating big eye, and rather slender black bill. Tends to perch quietly and upright, then slips off like a ghost and not seen again.