Thick-billed Kingbird

The thick-billed kingbird (Tyrannus crassirostris) is a large member of the family Tyrannidae, the tyrant flycatchers. It is found in the southwestern United States, Mexico, and Guatemala. == Taxonomy and systematics == The thick-billed kingbird has two subspecies, the nominate T. c. crassirostris (Swainson, 1826) and T. c. pompalis (Bangs & Peters, JL, 1928). The differences between them are slight and some authors suggest that the two should be merged. == Description == The thick-billed kingbird is about 25 cm (9.8 in) long and weighs about 52 to 59 g (1.8 to 2.1 oz). Females are slightly smaller than males and the sexes have essentially the same plumage. Adults of the nominate subspecies have a dark grayish brown forehead, crown, lores, and ear coverts; their cheeks are white. The crown feathers form a slight crest. Both sexes have a partially hidden lemon or canary yellow patch in the center of the crown though females' are narrower. Both sexes have a grayish brown nape that is paler than the rest of the head. Their upperparts are mostly grayish olive with grayish brown uppertail coverts. Their wings are mostly deep grayish brown with pale grayish olive lesser coverts. Their remiges have thin…