<P> The species is sexually dimorphic . The adult male has a gorget (throat patch) of iridescent ruby red bordered narrowly with velvety black on the upper margin and a forked black tail with a faint violet sheen . The red iridescence is highly directional and appears dull black from many angles . The female has a notched tail with outer feathers banded in green, black, and white and a white throat that may be plain or lightly marked with dusky streaks or stipples . Males are smaller than females and have slightly shorter bills . Juvenile males resemble adult females, though usually with heavier throat markings . The plumage is molted once a year, beginning in late summer . </P> <P> The breeding habitat is throughout most of eastern North America and the Canadian prairies, in deciduous and pine forests and forest edges, orchards, and gardens . The female builds a nest in a protected location in a shrub or a tree . Of all hummingbirds in the United States, this species has the largest breeding range . </P> <P> The ruby - throated hummingbird is migratory, spending most of the winter in southern Mexico and Central America, as far south as extreme western Panama, the West Indies, and southern Florida . During migration, some birds embark on a nonstop 900 - mile journey across the Gulf of Mexico and Caribbean from Panama to Gulf Coast . The bird breeds throughout the eastern United States, east of the 100th meridian, and in southern Canada, particularly Ontario, in eastern and mixed deciduous and broadleaved forest . In winter, it is seen mostly in Mexico and southern Florida . </P> <P> During migration southward in autumn along the northern coast of the Gulf of Mexico, older male and female birds were better prepared for long - distance flight than first - year birds by having higher body weights and larger fuel loads . </P>

Where do ruby throated hummingbirds go in the winter