Do Birds Sweat?

How Do Birds Keep Cool on Hot Days?

Mar 15, 2007 Rosemary Drisdelle

Birds don't sweat but they have other ways of cooling off when they get too hot.

Do birds sweat? Birds’ normal body temperature is higher than ours, so they don’t need to shed heat as soon, but they can get warm inside their thick layer of feathers. Birds don’t have sweat glands so they don’t sweat, but they have a few other ways to keep cool on hot days and get rid of excess body heat:

• Birds pant to expel body heat – they breath very quickly, letting the cooler air passing through the lungs and air sacs carry heat away from the body. A bird standing with its mouth open on a hot day is probably panting. The structure of a bird’s lungs allows the air to pass through in only one direction so it doesn’t mix with air that is already in the lungs (watch an animation). This means a greater cooling capacity as well as higher oxygen levels.
• Birds flutter the throat when they’re hot, flexing the hyoid bone. This area has a generous blood supply and thus can give off a lot of heat.
• Birds can elevate their feathers and hold their wings out a bit for air circulation.
• Bird’s legs are not covered with feathers and significant heat is lost through the legs and feet. Some species moisten and cool their legs by allowing liquid waste to run down them. Others cool their legs and feet by spreading their wings to provide shade. They may lift their feet off the ground to cool them as well.
• Birds turn their backs, or white parts, toward the sun so that their feathers will reflect the sunlight.
• Some birds wet their feathers or splash water on themselves for cooling. Others deliberately dampen their nests or the ground around them.
• Some birds have bald patches that allow heat to escape through the skin.
• To avoid overheating when it is very hot, many birds will rest in the shade during the heat of the day and be more active in the early morning and evening.

Small birds have a high surface-to-volume ratio and are susceptible to heat loss, so staying warm is more of a problem for them than cooling off. This is why very small birds, such as some hummingbirds, must consume a lot of high energy food and don’t do well in cooler climates.

Related content:

Why Do Birds Preen?

How Do Penguins Keep Warm?

Sources:

Ornithology.com "Metabolism and Thermoregulation."

Perrins, Christopher Ed. Firefly Encyclopedia of Birds. New York: Firefly Books. 2003.

The copyright of the article Do Birds Sweat? in Birds is owned by Rosemary Drisdelle. Permission to republish Do Birds Sweat? in print or online must be granted by the author in writing.

Comments

Dec 17, 2008 1:54 PM

Guest :

thanks this helped me for my school project!

Jun 2, 2009 12:24 AM

Guest :

what is bird sweating (or cooling down) called?

2 Comments