Unless you hear its loud, harsh calls, the rather secretive Great Crested Flycatcher is easily overlooked in foliage of a suburban lot or woodland. Vigilance may reward you with a flash of reddish brown or yellow, a glimpse of the raised crest, and the sound of a snapping bill as this large raucous flycatcher sallies forth to capture an insect or evict an intruder. This common bird of eastern North America appears to have benefited from the fragmentation of deciduous forest and subsequent increase in small woodlots and woodland edges. It is a summer resident throughout the southern Canadian provinces and all states east of the Great Plains, generally arriving by early May and departing by late September. Some Great Crested Flycatchers spend the winter in southern Florida and Cuba, but most travel to southern Mexico, Central America, and northwestern South America.
The Great Crested Flycatcher belongs to one of the largest genera of New World flycatchers; three close relatives occur in the southwestern United States, but others occur in the West Indies and Middle and South America. The species shows little geographic variation and is arguably one of the easiest to identify in a notoriously difficult genus.
An obligatory but secondary-cavity nester, the Great Crested Flycatcher is the only cavity-nesting flycatcher of eastern North America. It uses a wide variety of nesting cavities, including naturally occurring hollows in live trees created by branch scars and knotholes, cavities in dead trees excavated by woodpeckers, and a variety of human-made structures. Much has been written about this species' frequent use of shed snakeskin in the nest, which may be adaptive in regions where nest predation is high. Other items with a similar appearance (e.g., wrinkly plastic wrappers) are sometimes used in its place.
Although we know more about the behavior and distribution of the Great Crested Flycatcher than about any of its close relatives, some aspects of its biology are in need of further study—e.g., the existence and timing of the various molts, migratory routes, evidence for a sedentary population in central and southern Florida, fidelity to winter territory and/or winter range, and the size and function of the breeding territory.