Tyrant Flycatchers: Tyrannidae

There are more species in the family of tyrant flycatchers than in any other family of birds in the Western Hemisphere. Members of this family are found throughout North, Central, and South America. The family includes both migratory species that move from one climate to another as the seasons change and non-migratory species that remain in the same area year round. Only about thirty-seven of the more than four hundred species of tyrant flycatchers live in North America.

Tyrant flycatchers are perching birds with bodies that range in size from 3.5 to 11 inches (9 to 28 centimeters) and weigh from about 0.2 to 2.4 ounces (5.7 to 68 grams). This family includes some species that look very different from each other and other species that look so similar they cannot be told apart just by looking at them. In addition, males and females of many species look alike. Most members of this family are dull with brown, gray, or olive-green backs and ivory or light gray undersides. There are exceptions to this color pattern, including the vermilion flycatcher and the great kiskadee, both of which are brightly colored. Most species have moderate-length tails, although a few, such as the scissor-tailed flycatcher, have pairs of 6 inch long (15 centimeter) tail feathers that stream out behind them, almost doubling the bird's length.

Despite the diversity found in this family, tyrant flycatchers do have certain characteristics in common. All these birds eat insects, and they have developed short, wide bills with a slight hook at the end that help them catch and hold their food. Stiff stripped-down feathers consisting mainly of the feather shaft are found around the bill of most tyrant flycatchers. These are called rictal (RIK-tuhl) bristles. Originally it was thought that rictal bristles helped the birds catch insects while flying, but recent experimental evidence disproved this theory. Ornithologists, scientists who study birds, now think the bristles may help to keep insects out of the birds' eyes as they fly.

Tyrant flycatchers are good flyers. Those species that migrate have longer, more pointed wings designed for more efficient flight than those species that stay in one area year round. In non-migratory species the wings are shorter and rounder, a design that makes lifting off a branch easier. Because flycatchers spend little time on the ground, their feet and legs are weak.