How Birds Keep Their Cool
08/01/2012
A cardinal cools off in a birdbath. Photo: Michael Glasgow / CC BY-ND
As temperatures bake much of the United States and the nationwide drought continues, crops wither and fish die. But they aren’t the only ones suffering from the blazing summer. Birds are also trying to keep their cool. But they don’t sweat like humans, or even pant like dogs; instead, they have a variety of unique adaptations to help beat the heat.
In a study conducted on marsh sparrows in 2011, scientists found that bill size correlates to outside temperatures. Marsh sparrows with larger bills live in warmer climates, for example. The study noted that the tropical toucan also possesses a large bill, and has the ability to increase or decrease blood flow to its beak to either promote or prevent heat loss.
Laura Erickson of the Cornell Lab of Ornithology, however, points out that the size of a bird’s bill isn’t the only factor that keeps it cool.
“In the case of the raven, the further north you go the bigger their bills are,” says Erickson. “But they need the bigger bill to chip into frozen carcasses in the winter.” Instead, some birds rely on a variety of behavioral adaptations in order to regulate their body temperatures.
Some birds, like the great blue herons that star on the Cornell Lab of Ornithology’s nest cam, will open up their wings on a hot day, allowing air to circulate across their bodies and sweep away the excess heat.
“We’ve watched the adults move their bodies to shade the chicks,” says Erickson. Great blue herons will also “droop” their wings in addition to opening them to protect their nestlings from the sun. But researchers can tell that the posture does more than just keep chicks cool, because the birds also do it when they're off the nest.
These are only a couple of behaviors that birds use. When it’s hot, some species will also resort to gular fluttering. The bird will open its mouth and “flutter” its neck muscles, promoting heat loss (think of it as the avian version of panting).
“If you think about a dog panting, their tongue isn’t only allowing evaporation, but is losing a lot of body fluid,” says Erickson. “Birds are much more efficient about water and water loss.”
Even so, birds still need to replenish fluids on a hot day. Installing a birdbath can provide feathered friends with a place to cool their heels in the summer, and get a drink. The water level shouldn’t be too high—only about an inch deep—and the bottom of the birdbath shouldn’t be too slippery. Replenish the water once every two or three days. Otherwise, the stagnant water can play host to algae and mosquito larvae, which can carry the West Nile virus as adults.
Almost as important as water is shade. Temperatures can be far cooler under trees or bushes, and birds often seek out these microclimates. Since a bird’s body temperature is much higher than that of humans—a golden crowned kinglet was once found to have a body temperature of 111 degrees Fahrenheit—it’s doubly important for them to cool off in a hurry. Proteins that shuttle vital information to a bird’s organs begin to break apart at temperatures that are only slightly higher.
Climate change is expected to make droughts more frequent and extreme temperatures more common. And some bird populations are already being affected by the consequences of global warming. A study published in the Proceedings of the National Academy of Sciences reported that tree swallows laid their eggs up to nine days earlier because of warmer temperatures in the spring. Several populations of birds, most notably warblers, have also shifted their home ranges northward, and migration patterns are changing to accommodate the change in climate.
Together, these shifts indicate that birds are learning how to adapt to springs that feel like summers, and summers that feel like scorchers.
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Comments
We live in MO, and our
We live in MO, and our backyard is like a nature center with birds, bunnies, and squirrels. We have a large bird bath, a small ring bird bath that attaches to a deck railing, and in the winter is heated, a three tier fountain, and on the ground under a bush a stainless steel bowl of water for the rabbits. When it reaches over 90, I change their water two or three x a day, so it doesn't get too hot for them to drink. I have a shade over the Hummingbird nectar. I'm retired so I have the time to do this. I fill two squirrel feeders with all kinds of seeds, and cracked corn, so everyone is happy. The Finches have their own feeder. Keep one or two suet cakes going at all times. I spoil them and they are a joy to watch!
I have a bird feeder outside
I have a bird feeder outside my kitchen window that I fill every day. This weather was so hot 100 plus and the birds all had their beaks open like they were panting. One of my Bluebird pairs had the misfortune of starting a nest during this time and because of the heat, the babies hatched early. Two out of the three eggs hatched. I put ice cubes in the bowl on top of my feeder and changed them as they melted. My Bluebirds were the first to find the water. One egg did not hatch, but I had two that did. I have a videocam with their pictures during this time. I put an extra foamcore board on top of the Bluebird nest box so it was shaded all day which helped them, I'm sure. Terry
We have a fish pond in the
We have a fish pond in the back yard that is about 14 by 20 feet with various levels in it as well as a fountain in the center--we often have birds coming into drink and have a bath. I've watched small birds fly right though the spray of the fountain just like little kids at the water park, although I was not impressed when a King Fisher found my pond last year. LOL
During the "dog days" of
During the "dog days" of summer, grackles frequent the kiddie wading pool I put out for the birds. One in particular would fly in , light briefly on the rim, then jump in whirring his wings, splashing water everywhere. He was having fun while keeping cool.
Had watched smaller birds
Had watched smaller birds like parakeets and canaries as child open wings and do what I thought was stretching. My chickens, even ducks and geese took the time to dig holes, they fluff up in the dirt which helps control insects and disease, then with wings slightly opened they lie in these holes to keep cool.
I do not know if you can use electrolytes in bird baths but I use special one for fowl in my bird watering holes, wildlife get some too.
Cleaning bird baths often helps them also, guess I know what this weekend is.
Our birds enjoyed the three
Our birds enjoyed the three bird baths in our back yard this summer, especially the robins during their nesting period which required daily cleaning and watering of these baths. We have a variety of deciduous trees, conifers, and shrubs also which provided much heat relief for all the birds.
i saw a lot of robins using
i saw a lot of robins using my bird bath........the most surprising was........
a morning dove lying on its back with its wings spread open , as it seemed
to be airing them while in the bird bath.............
I've had mourning doves
I've had mourning doves splashing in my birdbath this summer also, and it isn't even very hot here. Usually it's only the scrub jays who bathe, and a pair of blackbirds. All the birds are drinking a lot, though!
We had a beautiful moment
We had a beautiful moment this July when a young Cooper's Hawk decided to cool off in our birdbath. I captured a quick video of it:
http://www.flickr.com/photos/alexfiles/7594647620/in/photostream
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The best time to plant a tree is twenty years ago. The next best time is now.
I thought that urohidrosis
I thought that urohidrosis was employed by some birds as a means of cooling off but it was not mentioned. Am I misinformed or is it used too little to be important?
Mine is a query. I am new to
Mine is a query. I am new to this page. I would like to know how and where birds spend the nights and in particular storms, day or night.
I also would like to know
I also would like to know where birds go at night!!! Marie
An Eastern Screech Owl
An Eastern Screech Owl spends every afternoon perched in the window over our front door. Is it trying to cool off by leaning again the glass?
Witnessed this myself this
Witnessed this myself this summer!
https://www.facebook.com/photo.php?fbid=10150947197989000&l=c6eb2ba9bf
I witnessed this first had
I witnessed this first had this summer with this Great Blue Heron!
https://www.facebook.com/photo.php?fbid=10150947197989000&set=a.38923383...
I've watched dozens of the
I've watched dozens of the small "brown" birds actually scuff dirt in the air as they dig 3-6" dips in my berms. They then roll in it and almost seem to playing in a splash pool with their friends and the soil. The soil is somewhat damp and cool. I assume that's their relief as the 85-95 air temps and drought is so extreme for them and me!
Not all have been seen in this activity. The cardinals, meadow larks and jays are only seen in the garden munching on all the fresh flower seeds.
While I have a few traditional bird baths, they seem to like the soil .
I've watched my Broad-banned
I've watched my Broad-banned Pigeons do that open-beaked, throat wattle thing. I have 3 bird baths & 5 fresh water containers on the ground for deer (including a very lame doe with 3 wee spotted fawns), raccoons, skunks, foxes, weasles & opposums. It is a privilege to get to live in Tehachapi, CA
It sounds like you live in a
It sounds like you live in a great place. Where is Tehachapi? I live in Long Beach and hope to move to northern ca. before I get too old.