Parting Thoughts

Birds’ Feet

By Noreen O’Brien, Purchasing,  Marine Parts Express

Birds’ hip joints are covered in feathers and the exposed parts that we see are the legs from the knee down and, contrary to what we think, their knees bend in the same direction as ours do. What we tend to think of as the knee, the joint we see as it bends, is actually the heel, and the long distance between the heel and the toes is called the tarsus. When referring to feet, we are speaking of just the toes, not the heel and tarsus, because these generally are not placed flat on a surface, as a human’s are.

The positioning of birds’ legs is based on the bird’s center of gravity, which, on passerines—perching birds—is at the center of the body, whereas waterbirds, such as loons or ducks, have theirs toward the rear of their bodies.

Most birds have four toes, with the exception of say, the Three-toed Woodpecker, or the Ostrich, which has only two toes. The hind toe, called the hallux, is like our big toe; birds’ feet have no equivalent to our little toe. Generally, the back toe is directed backward and is sometimes reversible, the others, forward.

The nails on birds’ feet are generally curved and sharp-pointed, round over the top, flattened from side to side and concave below. Birds’ feet serve many purposes, like perching and swimming, and as tools. For instance, some birds use their feet to gather nest materials or to collect food. How each species uses its feet determines the type of foot it has.

Some birds use their feet to kill and tear apart the flesh of their food, such as hawks, and their toes are deeply cleft, with large, strong, sharply curved nails (talons). Others, like woodpeckers, use their feet, with their extremely curved and sharp-pointed toes arranged in pairs, second and third in front, fourth and hallux behind, to cling to tree trunks or branches to collect their food with their bills.

Waterbirds, like ducks and swans, use their webbed feet as paddles to move about in the water, sometimes even as they sleep. And still others, like rails or gallinules, have very long toes that are capable of being spread wide, offering them balance when walking in marshes, and even atop lily pads.

Touch your finger to a baby’s palm and the baby automatically closes its fingers around your finger. When a bird lands on a perch, its feet do the same by a set of tendons acting as pulleys, pulling the toes inward automatically. Watch a handler hold a bird of prey and on the hand the bird is perched, they will be wearing a heavy glove, worn to protect the handler from sharp claws designed to catch or rip apart prey—or to grasp a perch.

A sleeping bird will have its head turned, tucked into its shoulder and, with the toes firmly grasping a perch, the bird has balance. As long as the birds’ feet are in contact with a perch, the toes remain in a grasping position, preventing it from falling off a perch for the hours it sleeps.

Look in a field guide at birds’ feet. When a bird lifts its foot, the toes automatically pull together, looking rather limp. They then automatically spread again when they make contact with a surface, or curl around a perch.

Watch carefully as birds land and take off at your feeders and you can see how their feet work. Watch, too, for the way they hold their feet in flight. Passerines hold their feet toward the front, close to their belly, while herons, for instance, fly with legs and feet outstretched behind them.

Ospreys have horny growths on the inside of their toes that help them to grip the fish they catch with their feet. Also, their feet are designed in such a way that their outer toe is reversible, making it possible to use two toes in front and two in back, making it easier for them to grasp slippery fish out of the water. If you carefully watch an osprey catch a fish, you can see the bird maneuver the fish to a headfirst position in its talons, while the bird is in flight, making it aerodynamic for the bird to continue its flight as it carries its meal to a perch for consumption.

Some birds have small and very weak feet, such as swallows. These birds catch their prey “on the wing,” that is to say, while in flight. Strong flyers, they usually have narrow, extremely pointed wings, large, gaping mouths to scoop insects as they fly and tiny feet, almost invisible in some birds, such as the Chimney Swift. They simply don’t use their feet for much besides perching, so their feet are “underdeveloped.”

Hummingbirds have tiny feet, but then, they have tiny everything. Hummers use their feet only for perching; their time is spent mostly on the wing hovering at flowers for their food, nectar. They have strong wings with rather amazing capabilities in their use of them, instead of well-developed feet. Hummers will hawk for insects, too. I have watched them zip out from a perch, capture a tiny bug and return to their perch, looking rather satisfied.

The feet of birds tell much about the bird, so do take the time to examine them at every opportunity. Learning some of these intimate details of a birds’ life adds a new dimension to your enjoyment of these winged creatures. Be sure to let me know of your observations.

Till next…

Noreen

Marine Parts Express makes sure that customers get the correct parts and this dedication is the “sole” of the company. Call us toll free at 877.621.2628

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Marine Parts Express is a division of Water Resources, Inc., a privately held Maine Corporation

Categories: Birds, Noreen O'Brien

Tags: bird feet, bird feet configuration, ducks, hawks, hummingbirds, Marine Parts Express, osprey, ostrich, three-toed woodpecker, waterbirds, webbed feet

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