The American Robin breeds throughout most of North America, from Alaska and Canada southward to northern Florida and Mexico. While robins occasionally overwinter in the northern part of the United States and southern Canada, most migrate to winter south of Canada from Florida and the Gulf Coast to central Mexico, as well as along the Pacific Coast. Most depart south by the end of August and begin to return north in February and March (exact dates vary with latitude and climate). The distance by which robins migrate varies significantly depending on their initial habitat; a study found that individual robins tagged in Alaska are known to travel as much as 3.5x further across seasons than robins tagged in Massachusetts.
Brown Thrashers are typically monogamous birds, but mate-switching does occur, at times during the same season. Their breeding season varies by region. In the southeastern United States, the breeding months begin in February and March, while May and June see the commencement of breeding in the northern portion of their breeding range. When males enter the breeding grounds, their territory can range from 2 to 10 acres (0.81 to 4.05 ha). Around this time of the year the males are usually at their most active, singing loudly to attract potential mates, and are found on top of perches. The courting ritual involves the exchanging of probable nesting material. Males will sing gentler as they sight a female, and this enacts the female to grab a twig or leaf and present it to the male, with flapping wings and chirping sounds. The males might also present a gift in response and approach the female. Both sexes will take part in nest building once mates find each other, and will mate after the nest is completed.