The Ruby-throated Hummingbird (Archilochus colubris) is the only hummingbird species known to nest east of the Mississippi River.

Male Ruby-throated Hummingbird

Female Ruby-throated Hummingbird

Description:

Average Length: 8.9cm or 3.5 inches

Average Weight: 3.1g or 1/8 ounce

Male: Emerald green back, iridescent ruby-red gorget that may appear black under some lighting conditions, gray flanks, forked tail with no white on it.  Smaller than the females.

Female: Emerald green back, white breast and throat, rounded green tail with white tips.  Larger than the males.

Immature: Young of both sexes look like the female.  In August and September, young males may develop some red spots in the gorget.

Molts: One complete molt per year, which may start during the fall migration and continue into March.  Young males acquire full ruby-red gorgets during their first molt.

Distribution:

Ruby-throats breed throughout eastern to Midwestern North America, from southern Canada to the Gulf of Mexico.  Most winter in Mexico, Central America, and on Caribbean islands, although a few may remain in the gulf states.