Tyrant Flycatchers: Tyrannidae

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TYRANT FLYCATCHERS: Tyrannidae

ROSE-THROATED BECARD (Pachyramphus aglaiae): SPECIES ACCOUNTS
GREAT KISKADEE (Pitangus sulphuratus): SPECIES ACCOUNTS
EASTERN PHOEBE (Sayornis phoebe): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

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.

GEOGRAPHIC RANGE

Tyrant flycatchers are found from the southernmost tip of South America to north of the Arctic Circle in North America. Species that summer in the Arctic usually migrate to Central or South America in the winter. The only area in the Western Hemisphere where tyrant flycatchers are not found is in the extreme northern edge of Canada.

HABITAT

Tyrant flycatchers live wherever insects live. They have adapted to tropical rainforests and deserts of the southwestern United States. They can be found in all types of forests, along steams, in grasslands, deserts and around human-made structures. They are most likely to be found in areas where trees, posts, or other spots to perch are combined with open areas.

DIET

Tyrant flycatchers are insectivores, eating mainly insects. However, certain species also eat berries, fruit, caterpillars, and worms. Some of the larger species eat small fish, frogs, lizards, and even mice or small birds, in addition to insects. Flycatchers' bills are adapted to the type of food they eat. The larger the food, the larger and stronger the bill must be. Bigger birds may beat their food against a branch until it is dead, then hold it down with one foot while pulling it apart with their bill.

When hunting for food, most tyrant flycatchers sit on a perch above the ground and remain still until they see an insect. They then fly out and snap the insect out of the air. As their bill closes, it makes clicking sound loud enough to be heard by human observers. The bird then returns either to the same or a different perch and waits for the next insect. This type of feeding is called hawking. Some tyrant flycatchers such as phoebes (FEE-beez) eat insects, caterpillars, and worms off the ground. These birds sit on a low perch until they see their prey, then fly down to the ground to pick it up, and return to a perch. They do not walk or hop along the ground hunting for food.

BEHAVIOR AND REPRODUCTION

Songs and calls are important in helping tyrant flycatchers recognize their own species, especially when several different members of this family live in the same area and look similar. Most species of tyrant flycatchers form pairs only for a single breeding season, choosing a different mate the next year. The female does most of the nest building, although the male sometimes keeps her company as she gathers material for the nest.

Tyrant flycatchers build many different types of nests in a variety of different locations. Many species build open cup-like nests in trees or shrubs. Some species nest in holes in trees, while others, such as phoebes, build nests of mud and plant material under bridges or under the eaves of empty buildings. Other species build bag-type nests that hang from branches over streams. Generally tyrant flycatchers select nest sites that offer some protection from predators and the weather.

Tyrant flycatchers lay two to eight eggs, and have one or two broods, or groups of young, a year. The female sits on the nest and incubates, sits on and warms, the eggs for about two weeks. The eggs hatch over several days, rather than all at the same time. Newborn tyrant flycatchers are almost naked and take two to three weeks to fledge, or develop feathers. During this time, both parents feed the young birds.

FIRST TO BE BANDED

The naturalist John James Audubon chose the eastern phoebe as the first bird to band, or tag, in the United States in 1840. He used information from these banded birds to find out where they migrated and whether they returned to the same places each year.

Tyrant flycatchers are territorial while they are breeding. They actively defend the area where they are nesting against other birds of the same or competing species and do their best to drive them away. Some tyrant flycatchers are very aggressive. The family gets the name tyrant from the behavior of kingbirds, which sometimes fearlessly attack larger birds.

Tyrant flycatchers that nest at the extreme edges of their range—either in the Arctic or near at the southern tip of South America—migrate hundreds of miles to warmer climates in order to find food when cold weather sets in. Other species that live in less extreme climates move much shorter distances or not at all. Migrating birds tend to return to the same nesting area each year.

TYRANT FLYCATCHERS AND PEOPLE

Tyrant flycatchers are neither dangerous nor particularly useful to humans, although they do eat large numbers of insects and may help to control the insect population.

CONSERVATION STATUS

Two tyrant flycatchers found in Brazil, the Alagoas tyrannulet and the Minas Gerais tyrannulet are Critically Endangered, facing an extremely high risk of extinction in the wild, because of rapid habitat loss and small populations that are widely separated. Nine other members of the tyrant flycatcher family, eight in South America and one in Cuba, are Endangered, facing a very high risk of extinction, for similar reasons. Fifteen additional species, none of which are in North America, are Vulnerable, facing a high risk of extinction.

ROSE-THROATED BECARD (Pachyramphus aglaiae): SPECIES ACCOUNTS

Physical characteristics: The rose-throated becard is one of the more colorful members of the tyrant flycatcher family. It is a moderate sized bird about 6.5 to 7.3 inches (16 to 19 centimeters) long with strong black bills. Males and females look different. Males have a dark gray head, gray back, light gray undersides, and a bright rose-colored throat patch. Females are dark brown on top and tan underneath with no rose color on them at all. Young birds have the same color pattern as adult females.

Geographic range: Rose-throated becards live year round from northern Mexico through Panama in southern Central America. During spring and summer breeding season, they can also be found in the United States in southeastern Arizona and the Rio Grande valley of Texas.

Habitat: Rose-throated becards live along the edge of forests, in wooded canyons and mountainous areas. They prefer places with tall trees, such as sycamores (SIK-ah-mohrz), near open areas.

Diet: Rose-throated becards eat insects, insect larvae (LAR-vee), and some berries. They hawk for food, sitting on a perch, then flying out to snap an insect out of the air.

Behavior and reproduction: Rose-throated becards choose a single mate and lay two to six eggs once each year. Female do most of the nest building. The nest is round and hangs from a tree branch. Females incubate the eggs for just over two weeks. Both parents feed the young, which leave the nest around three weeks after birth.

Rose-throated becards and people: Rose-throated becards are attractive to birdwatchers, but have little other known importance to people.

Conservation status: Large populations of rose-throated becards exist. They are not in immediate danger of extinction. ∎

GREAT KISKADEE (Pitangus sulphuratus): SPECIES ACCOUNTS

Physical characteristics: Great kiskadees, also called kiskadee flycatchers, are one of the larger, more colorful tyrant flycatchers. These birds are about 9.8 inches (25 centimeters) long. Males and females look the same. They have a black and white lined head, brown back and wings, white throat patch, and bright yellow undersides.

Geographic range: Great kiskadees are found in the United States in southwest Texas, and from northern Mexico through Central America, and in South America east of the Andes Mountains and as far south as Paraguay.

Habitat: Great kiskadees live in semi-open country with scattered trees. They are often found at the edge of forests and along streams.

Diet: Great kiskadees eat insects, but also will eat small fish, tadpoles, lizards, and mice. They will dive into the water after food, which they bring to their perch and beat against a branch until it is dead before tearing it apart. If they cannot find their preferred food, great kiskadees will eat fruits and berries.

Behavior and reproduction: Great kiskadees are aggressive and will chase larger birds out of their territory. These are large, active, noisy birds with a loud, harsh, call that sounds like their name. They mate with a single partner and build round nests on trees or utility poles. The female lays two to five eggs, two or three times a year. The young hatch in about two weeks and are fed by both parents before they fledge, grow feathers, and leave the nest about three weeks after birth.

Great kiskadees and people: Great kiskadees are often found around houses and gardens. They are common in many areas, but do not have a special significance to people.

Conservation status: Great kiskadees are abundant in much of their range, although their populations are declining in Texas due to development. They are in no danger of becoming extinct. ∎

EASTERN PHOEBE (Sayornis phoebe): SPECIES ACCOUNTS

Physical characteristics: Eastern phoebes are about 7 inches (18 centimeter) long with gray-brown heads and backs, white undersides, and black bills, legs, and feet. Males and females look alike.

Geographic range: Eastern phoebes are found east of the Rocky Mountains in the United States and Canada. They are migratory birds, moving north to nest in the summer and south to winter in coastal South Carolina, Georgia, Florida, and along the Gulf of Mexico as far south as the Yucatán Peninsula in Mexico.

Habitat: Eastern phoebes live in open land along the edge of forests and along rivers and streams. They survive very well close to human-made structures such as bridges, roads, and farms.

Diet: Eastern phoebes hawk for insects. They will also eat small fish and berries.

Behavior and reproduction: Eastern phoebes mate two or three times a year, usually with the same partner. They build a cup-shaped nest out of mud attached to a vertical wall, such as a cliff, pole, or building.

Eastern phoebes and people: Eastern phoebes often live near human structures and take advantage of them as places to build nests. They eat large numbers of insects, but are not especially significant to people.

Conservation status: Eastern phoebes are common in many parts of their range and are in no immediate danger of extinction. ∎