The thick-billed kingbird (Tyrannus crassirostris) is a large bird in the family Tyrannidae, the tyrant flycatchers. This bird breeds from southeastern Arizona, extreme southwestern New Mexico, and northern Sonora, (the Madrean sky islands), in the United States and Mexico, through western and western-coastal Mexico, south to western Guatemala. These birds are mostly resident in territories year round, but birds in the United States will retreat southward for the winter. They wait on an open perch usually rather high or on top of the tree and fly out to catch insects in flight, (hawking).