As summer intensifies across many parts of the United States, the mercury frequently climbs into the triple digits, turning once pleasant afternoons into sweltering tests of endurance. While humans retreat to air-conditioned comfort, the birds in our backyards and wild spaces continue their daily lives under the scorching sun. It’s natural to wonder how these seemingly delicate creatures cope with such extreme heat, especially when their small bodies are covered in insulating feathers. The truth is, birds possess remarkable adaptations to survive, and even thrive, during 100-degree days. Birds employ a combination of physiological and behavioral adaptations to cope with extreme heat.

Photo by Max Fomin

Panting/Gular Fluttering

Gular fluttering is the rapid vibration or oscillation of the moist membranes rich in blood vessels in a bird’s throat, specifically the floor of its mouth and upper throat area (the gular region). When a bird engages in gular fluttering, you’ll see its throat rapidly moving up and down, almost like a frantic pulsation, without necessarily opening its beak extremely wide or panting with its chest. The principle behind this is evaporative cooling, the same mechanism that cools humans when sweat evaporates from our skin. Here’s the step-by-step process:

By rapidly fluttering their gular membranes, birds create a rapid flow of air over these moist surfaces. This region is kept moist with mucus and saliva and as air passes over the moist membranes, water evaporates from the surface. The process of evaporation requires energy, which is drawn in the form of heat directly from the bird’s blood flowing through the capillaries in these membranes. This cooled blood then circulates back into the bird’s body, helping to lower its overall core body temperature.

Photo by Timothy A. Gonsalves

Seeking Shade

Direct sunlight delivers a massive amount of radiant heat directly onto a bird’s body. Even if the ambient air temperature is high, being out in direct sun significantly increases a bird’s heat burden, forcing its physiological cooling mechanisms (like gular fluttering) to work much harder. Shade blocks this direct radiation. 

While shade doesn’t cool the air itself, shaded areas often have a slightly lower ambient temperature due to the absence of direct solar heating on surfaces. By seeking shade, birds reduce the initial heat they need to dissipate, thus conserving precious energy that would otherwise be spent on cooling. This is crucial for their survival, especially during demanding periods like nesting.

Reduced Activity

Every physical activity a bird undertakes generates metabolic heat. Just like humans get warmer when they exercise, birds’ bodies heat up when they fly, forage, sing, or interact. In extreme heat, this internally generated heat becomes an additional burden on their thermoregulatory systems, making it harder to stay cool. By reducing activity, birds directly spend less energy and conserve water.

During the peak heat hours of a 100-degree day, the vibrant avian world often becomes eerily quiet and still. You’ll notice less foraging and hunting. Instead of actively hopping through bushes for insects or soaring to catch prey, birds will perch motionless in shaded areas. Foraging in direct sun or on hot surfaces would quickly lead to overheating. The enthusiastic dawn chorus gives way to silence. Singing, calling, and territorial disputes (which are very energy-intensive) largely cease during the hottest parts of the day. The energy used for the vocal cords could instead be directed towards cooling.

Photo by Gail Hampshire

Fluffing or Sleeking Feathers

The primary purpose of fluffing feathers is to trap a layer of air close to the bird’s body. Air is an excellent insulator. By increasing the volume of trapped air, birds create a barrier that slows down heat transfer. Tiny muscles at the base of each feather allow birds to erect or raise their feathers, creating air pockets between the feathers themselves and between the feathers and their skin. While most commonly associated with cold weather (to trap warmth), fluffing can also be employed in very specific hot-weather scenarios to block radiant heat.

The opposite of fluffing is seeking, which involves compressing the feathers tightly against the body. This reduces the amount of trapped air, allowing heat to escape more easily from the bird’s skin. Birds use their feather muscles to press their feathers down flat and tight against their bodies, often appearing slender or sleek. Sleeking is the more common posture observed in birds actively trying to cool down during hot days.

You might see a bird quickly switch between these states depending on its immediate needs and the changing conditions. For example, a bird might sleek down while panting in the shade, but briefly fluff up if it lands on a scorching hot rock before quickly seeking another perch.

Drooping Wings

Drooping wings is a distinct behavioral adaptation that many birds, particularly larger species or those under significant heat stress, employ to help dissipate excess body heat. It’s a relatively simple yet effective strategy that works by increasing the exposure of less insulated areas and promoting convection. When a bird is drooping its wings, it will hold them slightly away from its body, often with the primary feathers (the long flight feathers at the wingtips) hanging downwards and slightly fanned. The wings might appear relaxed and not held tightly against the body as they normally would be. This posture can range from a subtle loosening of the wings to a more pronounced lowering, sometimes almost touching the ground in very hot and stressed individuals.

The ‘armpits’ and the undersides of a bird’s wings are typically less densely feathered than the rest of its body. Some species also have bare patches of skin here. These areas have a richer network of blood vessels closer to the surface. By drooping and slightly extending their wings, birds expose these less-insulated regions directly to the surrounding air. With the wings held away from the body, air can circulate more freely around these exposed, warm areas. As air passes over the skin, it picks up heat and carries it away from the bird’s body through convection. This is similar to how a fan cools us down – by moving air across our skin.

Photo by Mohan Nannapaneni

Bathing and Splashing

Bathing and splashing in water is a vital and often delightful behavior to observe in birds, especially on scorching days like the 100-degree Fahrenheit heat of the summer. While it serves a crucial hygienic purpose for feather maintenance, its role in thermoregulation becomes paramount during heat waves.

The cooling effect of bathing is rooted in the principle of evaporative cooling. When a bird splashes and submerges itself in water, its feathers become saturated. As the water evaporates from the wet feathers, it draws heat away from the bird’s body. This is the same reason we feel cooler after a swim or when sweat evaporates from our skin. Some water may also reach the bird’s skin, especially in less densely feathered areas, providing direct cooling.

While primarily external, the act of splashing and the immediate drop in external temperature can help to lower the bird’s overall heat load, reducing the need for more energy-intensive internal cooling methods like gular fluttering.

Perching in Breezy Spots

Perching in breezy spots is a simple yet highly effective behavioral adaptation that birds employ to shed excess heat, especially on very hot days. A breeze works by constantly sweeping away this warmed boundary layer of air and replacing it with cooler, fresh air. This continuous removal of heated air accelerates the rate at which heat is drawn away from the bird’s body. The faster the air moves, the more efficient the heat transfer.

Birds will strategically choose perches that maximize their exposure to airflow. Examples of this are elevated perches like the tops of trees or the edge of cover where they get the advantage of a breeze but the safety of cover. Birds will often orient their bodies to face directly into the wind. This presents a streamlined profile, allowing the air to flow efficiently over their body surface, particularly their less-insulated head and feet.

Photo by Jes-Mey-Lumix

How You Can Help

The best way to help birds with shade is to enhance their natural environment. The most impactful long-term strategy is to plant trees and dense shrubs. Prioritize native species that will thrive in your local climate and provide excellent cover. With existing plants, avoid over-pruning trees and shrubs, especially during summer months, as this removes valuable shade. For smaller gardens, a shade cloth over a bird bath or a dense potted plant can offer some temporary relief. By providing ample, diverse shade in your backyard, you offer birds a crucial refuge during extreme heat, allowing their natural cooling mechanisms to work more efficiently and preserving their precious energy.

Give Them Space

One of the most underrated ways to help birds during their period of reduced activity is to avoid disturbing them. Minimize loud noises, gardening, or outdoor activities that might force them to move or expend energy unnecessarily. If you have plenty of cover, remember that hot birds are likely to be hidden in them trying to keep cool. 

You should also be aware of different behaviors in the hot summer months. For instance, it can look alarming when you see a bird spread out on the ground in the sunshine. Don’t rush to help as they are probably ok. Sunbathing is a natural and beneficial self-care behavior. Instead, focus on providing resources that help them cope with actual heat stress when they are struggling.

Photo by Mark Timberlake

Focus on Water

Providing water for bathing is arguably the single most helpful thing you can do for birds on a hot day. So, ensure ample, clean, and shallow water sources are available, as they might make quick, targeted trips for drinking and bathing, which helps them cool down internally and externally, making feather sleekness more effective. If possible, offer multiple baths and place them in different locations – some in the open, some in shade.

Keep the water shallow and provide a rough surface, as smooth plastic or stone can be slippery. A rough texture or some stones/pebbles in the bath provide better grip. It is really important to refill with fresh, cool (but not icy) tap water throughout the day as it evaporates or becomes dirty. In hot weather, water fouls quickly. Scrub the bird bath daily with a stiff brush and rinse thoroughly. Avoid harsh chemicals.

Harness the Breeze

While you can’t create wind, you can facilitate birds’ access to breezy spots. Keep some tall, exposed perches (like dead branches in a tree, or an uncluttered clothesline) available in your yard. Long-term, planting tall trees will provide future high, airy perches. If possible, place feeders or bird baths in areas where they might catch a gentle breeze, while still being safe from predators and having nearby cover. By providing varied perching opportunities, including those exposed to air currents, you give birds more options for regulating their temperature effectively on scorching days.

Photo by Derek Keats

Final Thoughts

Birds have all the physical and behavioral adaptations and engineering to cool themselves down in hot weather. There is nothing we can do to improve those activities, and birds should be left alone to help themselves. However, there are two things you can do to help overheating birds. Firstly, provide water. Bird baths provide drinking and bathing water that hydrate and cool down birds.

It is vital, however, that they are kept clean with fresh water in them. Secondly, cultivate your garden so it provides different levels of perches, lots of dense and cooler areas, as well as peace. Then, leave them alone to do what nature has intended – drooping wings, gular fluttering, and bathing or resting in the shade. Looking to photograph some amazing birds this summer? Here’s our shortlist of species to look for!