Avian Anatomy 101

Know Your Bird Inside and Out!

Rock dove or pigeon
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Part of being a responsible bird owner is doing everything within your power to ensure your pet's good health. The first step in doing your part to keep your bird in top condition is to learn about how your pet's body works.

Birds are physiologically different from any other creature on the face of the earth. While they need to eat, drink, and breathe the same as we do, the parts of their bodies that carry out these functions differ drastically from our own.



Starting with a bird's external anatomy, we'll explore the unique parts that make up your feathered friend.

External Bird Anatomy

  • Beak: A bird's beak serves many purposes -- such as eating, grooming, and of course, singing! The beak is an extension of the bird's jaw bone, and is covered in keratin, the same substance that makes up our fingernails. The top part of the beak is called the cere, and is where the bird's nostrils, or nares, are located.

  • Eye: Whoever came up with the phrase "eagle eye" wasn't joking -- birds have extraordinarily accurate vision. The eye holds scores of receptor cells, called rods and cones, that translate whatever the bird looks at to the image that it sees. To give an idea of how sharp their sight is, humans typically have around 200,000 of these cells per millimeter inside of their eyes. Some birds, particularly birds of prey, have five times that many!

  • Wings: A bird's wings are constructed of a series of small thin bones similar to miniature versions of the bones in human arms. Externally, the wings are home to several different kinds of feathers: the Primary Flight Feathers, the Secondaries, the Main and Lesser Coverts, the Tertials, and the Alula.

  • Foot: The feet and legs of birds vary greatly depending on the species. Generally the legs, feet, and claws are structured to allow a bird to take off, land, climb, and grasp with them. Since birds spend most of their lives perching, the feet and legs are covered with a tougher skin than the skin on the rest of the bird's body.

  • Tail: During flight, a bird's tail acts much like the tail of an airplane -- it's used like a rudder to help the bird steer. The muscles of the tail also aid in helping the bird expand its lungs to take in extra air when needed.

  • Anus: The anus is the external opening through which the bird passes waste.

Internal Anatomy

Birds are just as different from us on the inside as they are on the outside. Read on to learn about the different parts that keep your pet going!

  • Brain: Being called a bird brain isn't necessarily a bad thing -- in fact, some may take it as a compliment! Birds are in fact extremely intelligent creatures, and as any bird owner knows, they never fail to surprise us with their capacity for learning.

  • Spinal Column: Like all vertebrates, birds have a spinal column that runs the length of their bodies, and encases the delicate spinal cord. The spinal cord is part of the central nervous system and, in essence, acts as the brain's "messenger". When the bird decides that he wants to move, the spinal cord relays the message from the brain to the muscles that correspond to the desired body part, causing movement.

  • Trachea: The trachea is a long tube that runs from the bird's throat to its lungs, and transports fresh air for the bird to breathe.

  • Esophagus: The bird's esophagus is a narrow tube that transports food from the mouth to the crop, where it will be stored until it is digested.

  • Lung: Much like human lungs, avian lungs serve to diffuse air throughout the bird's bloodstream. They are unique, however, in the fact that they have small air sacs that allow air to flow through the lung in only one direction, ensuring a constant supply of fresh oxygen.

  • Crop: In the same way that a chipmunk stores food in it's cheeks, birds store food in their crops. The crop is composed of layers of muscle tissue, and holds and softens the food until it's ready to be passed on to the gizzard.

  • Gizzard: A gizzard is a structure composed of tough muscle tissue which contains roughage that is used to grind the bird's food into a pulp. When the food is sufficiently ground, it is passed into the bird's intestine.

  • Kidney: Liquids that the bird ingests are passed into the kidneys, which filter out any waste to be expelled from the bird later.

  • Heart: Much like our human hearts, a bird's heart is divided into four chambers and serves to pump oxygen-rich blood throughout the body. Because birds are such high-energy animals, their hearts beat much faster than those of mammals. Some bird species have a resting heart rate of over 500 beats per minute!

  • Liver: A bird's liver acts much like a large filter, and rids the bird of any toxins in its body.

  • Ureter: The ureter is a tube that extends from the kidney to the cloaca, and allows liquid waste to be expelled from the bird's body.

  • Intestines: A bird's intestines work to digest the food that is pumped into them from the gizzard, absorbing the nutrients that the bird needs to function. After the food is digested, the waste is pushed into the rectum.

  • Rectum: The rectum allows waste to be expelled from the bird's body.

    While birds possess many body parts that are similar to our own, they also have parts that are extraordinarily different. By learning the function of these parts, we can become prepared, informed bird owners -- a very good thing to be in the event of an emergency.

    Congratulations on taking the first step toward a long and happy life with your pet. You never know when a little bit of knowledge can save the day!