Tree Swallow

Description: 5-6 1/4" Sparrow-sized, the only swallow in the east with metallic blue or blue-green upperparts and clear white underparts, young birds are dull brown above.	Habitat: Freshwater marshes, wetlands, brackish ponds and marshes, wet meadows, wooded habitat near water, especially where dead trees are abundant. Migrates in large flocks during the day. Will nest in man-made boxes.
Nesting: 4-6 white eggs in a feather lined cup of grass placed in a hole in a tree or in a nest box.	Range: breeds from Alaska across north Manitoba, south to Gulf Coast and Carolinas
Voice: constant liquid twittering and chattering	Diet: insects mostly, also berries and seeds

Notes: Often nest in loose colonies. Occasionally polygynous, possibly when food supplies are superabundant. Juveniles often seen as attendants at non-kin nests but do not serve as helpers -- in fact, they attempt to steal food from nestlings and parents! Clutch size larger and nestling survival greater when food very abundant. Hatch asynchronously. Nestlings brooded by female for 5 days. Starlings, House Sparrows, House Wrens, bluebirds compete for nest cavities. Only North America passerine in which females do not attain full breeding plumage at one year. Form large premigratory communal roosts; huge flocks perform preroosting aerial displays.

When present in Oklahoma: mostly in eastern OK but scattered elsewhere all year