The following 4 hummingbird species are known to occur in Kentucky.
Ruby-throated Hummingbirds, Archilochus colubris – Native – Quite common summer visitors. Usually arrive in mid-April, although some come as early as late March. Mating and nesting usually occurs in June. They usually return to their wintering grounds in Mexico and Central America by late July. Some of them migrate south later, but usually they are all gone by the end of September. Migrating males are usually the first to arrive and the first to depart. The females and the young usually follow about two weeks later.
The male has a ruby-red throat, a white collar, an emerald green back and a forked tail.
The female has a green back and tail feathers that are banded white, black and grey-green.
Rufous Hummingbirds, Selasphorus rufus – Seasonal
These hummingbirds are usually found in gardens and at feeders. These birds are fearless, and are known for chasing away other hummingbirds and even larger birds, or rodents away from their favorite nectar feeders and flowers.
Males can easily be identified by their glossy orange-red throats.
Females have whitish, speckled throats, green backs and crowns, and rufous, white-tipped tail feathers.
Rufous Hummingbird versus the similar Ruby-throated Hummingbird (Identification)
Black-chinned Hummingbirds, Archilochus alexandri
The male has a black, shimmering throat with a purple edge and pale feathers below that create a collar. However, unless the light is just right, the head looks all black. His back is green and there are some green feathers covering the chest.
The female is pale below (sometimes with a slightly speckled throat) and her back is green.
Green Violetears (Colibri thalassinus) – Rare – They are mostly resident in Mexico and Central America, but some seasonal movements have been observed. They may wander north to the United States and even as far north as Canada.