23-3-2017 TROGON LODGE, COSTA RICA - TREE SWALLOW (Tachycineta bicolor)

The Tree swallow (Tachycineta bicolor) is a migratory bird found in the Americas. It was first described in 1807 by French ornithologist Louis Vieillot as Hirundo bicolor. This bird spends most of its time flying and chasing after insects in acrobatic twists and turns. Because of its large range and stable population, the Tree swallow is considered to be least concern by the International Union for Conservation of Nature. In the US, it is protected by the Migratory Bird Treaty Act of 1918, and in Canada by the Migratory Birds Convention Act.

The male Tree swallow has mostly glossy blue-green upperparts, the wings and tail being blackish. The underparts and the cheek patch are white, although the underwing coverts are grey-brown. The bill is black, the eyes dark brown, and the legs and feet pale brown. The female is duller in colour than the male, and sometimes has a brown forehead. The second-year female also has brown upperparts, with a variable number of blue feathers; some third-year females also retain a portion of this subadult plumage. The juvenile Tree swallow can be distinguished by its brown upperparts and grey-brown-washed breast.

Tree swallows breed in the United States and Canada. They winter along southern US coasts, along the Gulf Coast, to Panama and the northwestern coast of South America, and in the West Indies. The breeding habitat of these birds is primarily open and wooded areas, especially those near water; these may include marshes, ponds, bogs, wooded swamps, and lakes. Tree swallows prefer to rest in cane or reed beds over water, but may also be found over land and on trees and wires.