How the birds keep cool in the summer heat
Whether your skin is covered by fur, feathers or fabric; you’ve noticed something over the past week or so: It’s darn hot outside.
Excessive heat – and how to deal with it – is often a topic of headlines and conversations at this time of year. We humans try to combat the summer heat by spending more time indoors, more time in the shade, more time consuming large amounts of cool beverages – or all of the above.
Wildlife can’t crank up the air conditioning when outside temperatures heat up, but there are certain physical characteristics and behavior modifications that help them cope with hot weather. To get an idea of some of the adaptations animals make to beat the heat, let’s look at what is perhaps our most watchable wildlife – birds.
Birds don’t sweat, so they cannot rely on the body-cooling tactic that’s effective for humans and most other mammals. But they have developed other ways to stay cool.
When there’s a breeze you may see birds fluttering their wings, spreading their wings slightly or puffing out their feathers. This lets the circulating air reach the hotter parts of their body and is the equivalent of when humans get in front of a fan and raise their arms slightly to let the cooling breeze circulate under their arms.
Vultures have an effective – though, to us, it may seem disgusting – way of staying cool in summer: They defecate on their legs. Their fecal matter is a solid-liquid slurry type of mixture and as the liquid component evaporates, it cools the legs. This process, called urohydrosis (also spelled urohidrosis), serves the dual purpose of cooling and sanitizing. A vulture’s fecal material contains a high amount of uric acid which kills bacteria and other organisms that may have been transferred from the dead carcass onto the vulture’s legs during feeding.
Another thing vultures, hawks and other birds that soar may do during hot times is fly at higher altitudes. This does not get them out of the sun, but it does get them up to levels where air temperatures are cooler.
Turkeys use their wattle – that red flap of skin on their throats – to help stay cool. Blood pumps through the wattle close to the surface of the skin and this helps to displace body heat and cool the bird.
All birds may not have wattles, but they have patches of bare skin that help them stay cool. These patches of un-feathered skin on their legs, feet and around their eyes can help dissipate heat.
In addition to these traits, birds also utilize some stay-cool methods we’re familiar with; stay in the shade during the hottest part of the day, become less active when it’s hot and stay near water. The last of these reasons is why it’s important to keep bird baths filled with water (and to change it frequently) during these hot times so birds can drink, bathe and cool themselves. If you have a larger bird bath, you may even consider adding some small flat rocks to provide small birds with places to perch, drink and bathe.
More information about what birds and other animals do in summer – and at other times of the year, as well – can be found at your nearest Missouri Department of Conservation office or atmdc.mo.gov.
Francis Skalicky is the media specialist for the Missouri Department of Conservation’s Southwest Region. For more information about conservation issues, call 417-895-6880.