The Columbiformes order of birds are pigeons and doves. This family has over 300 species in 41 groups. Pigeons and doves are usually less than 1 foot long and have short tail feathers with black tips. One of the most common pigeons in the United States is the rock pigeon (Columba livia). Other pigeons and doves are spotted doves, speckled pigeons, white-headed pigeons and turtle doves.
Also referred to as perching birds, passerines are arboreal species that live the majority of their lives in trees. These birds use trees for nesting and finding food. Approximately 60 percent of all birds are passerines, according to Stanford University. Although some passerines exceed 1 to 2 feet in length, most species are under 1 foot long. Short-tailed pygmy-tyrants, manakins, scrub-birds, stitchbirds, goldcrests, swallows and warblers are some small passerines with short tails.
The order Apodiformes represents the small-bodied hummingbirds and swifts. Approximately 400 hummingbird and swift species live in the world. One Apodiformes bird, the bee hummingbird (Mellisuga helenae), is one of the smallest birds in the world at approximately 2 inches long; this bird is native to Cuba. Hummingbirds are nectivores, since over 90 percent of their diet is flower nectar; these birds also eat insects.
Woodpeckers are one of the most recognizable North American species of the bird order Piciformes. These small birds use their beaks to drill cavities into trees to create nesting sites. The Piciformes order of birds has approximately 400 species. All of these birds may be identified by their feet, which have two toes pointing forward and two toes pointing backward. One small Piciformes bird, the downy woodpecker (Picoides pubescens), has a length of 5 to 7 inches.
Podicipediformes represent 22 species of grebes, which are small aquatic ducks. Grebes are diving ducks with webbed feet and short tails. A grebe's diet primarily consists of insects and crustaceans, but these birds also eat their own feathers. Least grebes (Tachybaptus dominicus) are one of the smallest Podicipediformes birds at 8 to 10 inches long. Grebes require running starts on water in order to fly.