Did you ever wonder why a bird doesn’t fall off of its perch when it's asleep? Or why there is such a variety of shapes and sizes of feet in the bird world? The legs and feet of birds are quite amazing. While they have some similar anatomical features as humans, they are uniquely constructed and located. Birds actually walk and grasp with their toes. The long shank part that we think of as the bird’s leg is really its foot! What we might think of think is the bird’s knee, with a reverse bend, is really its heel and ankle! The bird’s real knee is hidden up under its feathers.

     The overall construction of bird’s feet, are perfect for perching, running, swimming, wading, climbing, grasping, tearing or scratching. Each type is perfectly suited for where the bird lives and how the bird uses them. Bird feet are constructed of three single, rigid bones, with joints that work in opposite directions. Serving as shock absorbers, they actually cushion the bird’s landings.

     Most birds have four toes, although shorebirds have only three with a hub of a back toe higher up the back of its foot, if they have any at all. Shorebirds spend their time running around on mud flats and sand spits and a back toe would probably be a hindrance. Most perching birds have three toes forward and one toe back enabling them to grip stems and twigs. They have tendons, which run the length of their "feet." When a bird perches, its knees and ankles bend and automatically tighten this tendon. The tendon has projections that mesh and lock much like a ratchet, contracting the bird's toes so they grip tightly. The bird's toes and the bird itself are actually locked tight to their perch so they can't fall off.

     Birds of prey have strong feet with sharp, hooked talons. The eagles, osprey and peregrine falcon are prime examples. The osprey has spicules, or coarse foot pads on the bottoms of its toes. Like coarse sandpaper, they help the bird to catch and hold slippery fish. The peregrine falcon and the eagle have strong hind toes with a large claw. In the case of the peregrine, it is able to make a fist with which it knocks its prey out of the air on its power dives. The prey is knocked senseless to the ground or disabled enough so the falcon can come down and make the kill if it hadn't been accomplished with the first blow.

     Ospreys and owls have the capability of turning one of their front-facing toes backwards for better gripping power. The feet of climbing birds, like parrots, cuckoos and woodpeckers normally have two toes forward and two toes back. These "yoke-toed" birds can crawl around, hang upside down, or cling to the side of a tree or branch. Chimney swifts, the short little birds with narrow, fluttering wings that some people mistake for bats, have all four toes pointing forward to help them hang vertically on the insides of chimneys and to their stick nests. Birds that scratch on the ground for food like turkeys, quail, towhees, and white-throated sparrows have relatively short, thick toes with stout, blunt claws for scratching. Some birds have feet covered with feathers.
Wading birds like herons, egrets, bitterns, and ibises, have long slender legs for walking in the water. This allows them a high vantage point enabling them to spot small fish or frogs on which they feed and to keep their feathers dry. Most swimming birds have webbed feet. Waterfowl, cormorants, mergansers, loons, pelicans, and gulls have fully webbed feet because they spend most of their time in the water. There are variations of webbed feet as well. Some plovers and sandpipers have partial webs, known as semi-palmated. They are sometimes put in situations where they have to swim In water too deep to wade. Grebes and coots have lobed toes. They serve these birds well in swimming, diving, as well as being able to crawl around and through thick marsh vegetation. The lobes are like flaps. On a forward motion, they fold down alongside the toes to eliminate resistance, but flare out to present a rigid surface on the bird's backward power strokes. 
Gallinules or moorhens have long, slender toes for stepping on floating vegetation. The especially long toes distribute the birds' weight so they can walk over lily pads and other vegetation and not sink down. One of their nicknames is pad-walker. The Mexican Jacana has especially long toes.

     For owls it’s a silencing feature as well as insulation from the cold. The rough-legged hawk, a hawk that breeds in the Arctic, and makes occasional winter journeys into Virginia, spends much of its time in the tundra. It has feathered feet for protection plus its feet are noticeably smaller than other hawks its size. The trees in the tundra are stunted and smaller, so the rough-legged's smaller feet are more suitable for gripping and perching in smaller branches.

     Some birds actually grow snowshoes. The ruffed grouse develops hair-like appendages growing out from the sides of its toes. Shortening daylight hours in winter affects the birds pituitary gland triggering the growth of the "snowshoes," which aids the grouse in walking over soft snow by supporting its weight.
The legs and feet of birds show a wide array of shapes, sizes, and variations. Each type, a special tool, that serves a particular purpose in the birds' respective habitats, manner of getting food or building nests, each doing the job perfectly. 
     
© 2001 Spike Knuth All rights reserved