Adult Male Ruby-throated Hummingbird
Young male Ruby-throated Hummingbird
Photo by Allen Chartier
Adult male: Emerald green back, iridescent ruby red gorget (throat) that may appear black under some lighting conditions, gray flanks, forked tail with no white. Smaller than the female.
Adult female: Emerald green back, white breast and throat, rounded tail with white tips. Larger than the male, with longer bill.
Juveniles: Young of both sexes look like the adult female. In August and September, young males may develop some red spots in the gorget.
Copied from http://www.hummingbirds.net/rubythroated.html
Adult male: Metallic green back, crown, and breast (one photo shows a grayish breast); black gorget with purple throat band, white collar. The least colorful of US hummers.
Adult female: Green back and crown, white breast, white throat with some black spots, buff sides, white tips on outer tail feathers.
Copied from http://www.hummingbirds.net/blackchinned.html
Adult male: Non-iridescent rufous crown, tail, and sides; back may be rufous, green , or some of each; bright orange-red gorget, white breast. Green-backed Rufous cannot be reliably separated from Allen's in the field without extensive experience and a good view of the spread tailfeathers through a scope.
Adult female: Green back and crown, white breast, streaked throat, rufous sides and base of tail feathers, white tips on outer tail feathers. Very similar to female Allen's and Broad-tailed.
Copied from http://www.hummingbirds.net/rufous.html
Photo by Joe Misiaszek
Adult male: Metallic bronze-green head and back, iridescent coppery-red gorget (throat), rufous flanks. Smaller than the female.
Adult female: Rufous back and sides, white breast, white throat with some red spots, rounded tail with white outer tips. Larger than the male. Extremely difficult to differentiate from female Rufous.
Juveniles: Young of both sexes look like the adult female.
Adult male: Metallic green back and crown, white gorget with purple rays that may be erected to show a "whiskered" effect.
Adult female: Green back and crown, white throat with dark streaks, buff sides, white-tipped tail corners.
Adult male: Metallic green back and crown, white breast, rose gorget, rounded tail.
Adult female: Green back and crown, white throat and breast with black spots, rusty sides, green central tail feathers; outer tail feathers are rusty at base, black in middle, and white at tips.