“Birds are bipedal, warm-blooded, egg-laying vertebrates with about 10,000 living species. The fossil record indicates birds evolved from theropod dinosaurs 200 to 150 million years ago, and the earliest known bird is the late Jurassic Archaeopteryx. There is significant evidence that birds evolved from theropod dinosaurs; as more non-avian theropods that are closely related to birds are discovered, the formerly clear distinction between non-birds and birds becomes blurred. A genetically consistent evolutionary tree would classify birds as reptiles, though some scientists would elevate birds, turtles and crocodilians to their own class, on an equal footing with reptiles.
Globally, 1,223 species of birds, or about 12 percent of the total of 9,998 extant described bird species, were deemed endangered or threatened with extinction by IUCN’s 2009 Red List. In the United States, about 74 bird species are at risk, about 9 percent of the total. “(Center for Biological Diversity.)
The Eastern Phoebe (Sayornis phoebe) is a small passerine bird. This tyrant flycatcher breeds in eastern North America, although its normal range does not include the southeastern coastal United States.
It is migratory, wintering in the southernmost United States and Central America. It is a very rare vagrant to western Europe. This is one of the first birds to return to the breeding grounds in spring and one of the last to leave in the fall. They arrive for breeding in mid-late March, but they return to winter quarters around the same time when other migrant songbirds do, in September and early October; migration times have stayed the same in the last 100 years.The increase in trees throughout the Great Plains during the past century due to fire suppression and tree planting facilitated a western range expansion of the eastern phoebe as well as range expansions of many other species of birds.
This species appears remarkably big-headed, especially if it puffs up the small crest. Its plumage is gray-brown above. It has a white throat, dirty gray breast and buffish underparts which become whiter during the breeding season. Two indistinct buff bars are present on each wing. Its lack of an eye ring and wingbars, and its all dark bill distinguish it from other North American tyrant flycatchers, and it pumps its tail up and down like other phoebes when perching on a branch. The eastern phoebe’s call is a sharp chip, and the song, from which it gets its name, is fee-bee.
The Eastern Wood Pewee (Contopus virens) is extremely similar in appearance. It lacks the buff hue usually present on the lighter parts of the eastern phoebe’s plumage, and thus has always clearly defined and contrasting wing-bars. It also does not bob its tail habitually, and appears on the breeding grounds much later though it leaves for winter quarters at about the same time as the eastern phoebe.[
The breeding habitat of the eastern phoebe is open woodland, farmland and suburbs, often near water. This phoebe is insectivorous, and often perches conspicuously when seeking food items. It also eats fruits and berries in cooler weather.
It often nests on human structures such as bridges and buildings. Nesting activity may start as early as the first days of April. The nest is an open cup with a mud base and lined with moss and grass, built in crevice in a rock or man-made site; two to six are laid. Both parents feed the young and usually raise two broods per year. The Eastern Phoebe is occasionally host to the nest-parasitic Brown-headed Cowbird (Molothrus ater).
Information quoted from Wikipedia.