Cool facts about birds


Browse photos and interesting facts adapted from our Facebook posts.

Green Heron (Butorides virescens) with prey (Dori / Wiki; cc by-sa 3.0)

Some birds, like Green Herons, jays, shrikes, crows, owls and gulls, swallow part or all of their prey whole. Strong stomach juices digest the soft parts. Leftover parts — bones, teeth, fur, feathers, claws, etc. — are formed into pellets that are regurgitated later. Some birds routinely regurgitate from the same perch, leaving piles of pellets below — convenient for researchers who examine pellets to see what different bird species eat.


Long-eared Owl pellets. (BastienM / Wiki; PD)

Owls are birds who swallow their prey whole. Scientists have found Barn Owl pellets containing remains of many species, plus leg bands from titmice, chickadees and goldfinches. This photo shows pellets from a Long-eared Owl (Asio otus), some intact and some pulled apart to show their bits of matter, including bones.

Western Scrub Jay in fountain

Western Scrub Jay in fountain (Gleep!! / Flickr; cc by 2.0)

Birds cool their body by evaporating moisture through their skin and by panting. A study of desert birds shows that a summer temp rise of just 2 deg. F above normal can double the rate of water loss in small birds. Excessive evaporative water loss increases a bird’s body temperature and can lead to heat stroke and death. Unusual mass bird deaths have been reported across the U.S. in ultra-hot summers. 

Red-tailed and Great-horned

(© Ken Lockwood, Eagle Valley Raptor Center)

A Red-tailed Hawk and Great-horned Owl on the ground and locked in mortal combat!

Neither will let go! Why? Hunger — Great-horned Owls routinely prey on hawks. The hawk is trying to save himself, but also make a meal of the owl. They may have been hungrier than usual. It’s cold and snowy, prey may have been harder to find than usual. Great-horned Owls (Bubo virginianus) also prey on hares, rabbits, rodents, opossums, woodchucks, bats, weasels, other owls and even skunks. Sometimes domestic cats. They’re pretty ferocious and sometimes kill more than they can eat. They cache the extra for eating later. About this photo: Ken Lockwood (Eagle Valley Raptor Center, Cheney, Kans.) was called to the scene by a bystander, to separate the birds, who appeared injured. Except for ruffled feathers, the owl was fine. The hawk had leg injuries and was cared for until healed, then successfully released.

Bird Gastro

Bird Digestive System (Erik Beyersdorf / Wiki; cc by-sa 3.0)

Birds don’t have teeth to pulverize their food, so their digestive system has a specialized way of breaking it down. After food is swallowed it goes into their “crop,” an enlarged pouch in the esophagus. From there, it goes into a stomach that has strong digestive juices and from there into their gizzard, which has strong musculature for grinding. Once it’s sufficiently converted into a digestible mash, it flows into their intestines. (Sometimes, birds swallow small stones or grit to help in the grinding process.)


Rufous hummingbird (Selasphorus rufus) (techno-nanna / Flickr; cc by-nc 2.0)

Do you leave your hummingbird feeder out in winter? Even if you live in a more northern climate, it might help a late migrant or even supplement the diet of other winter visitors. Use 1 part sugar to 4 parts water. As in summer, keep the solution fresh and the feeder clean. In winter the solution ferments slower, so the feeder will need cleaning only every week or two. The nectar won’t freeze unless the air temperature drops to around 29 F. (You may want to use two feeders and rotate them in and out to keep them from freezing.) If you have to bring it in overnight, put it out as early as possible in the morning.

Sparrow napping

Sparrow napping. (Lucas Vermeer / Flickr; cc by-sa 2.0)

Birds expend more energy in winter and are often forced to spend all day looking for enough calories to carry them through the night. By offering them seeds, nuts, suet, we give them an opportunity to spend part of their daytime hours resting and conserving energy.

Bird eating cheese

Bird eating cheese. (© Keith Levit / 123RF)

Do you feed bread to birds? They’ll eat it, but experts say other kitchen scraps are better, as bread doesn’t contain any of the vital nutrients birds need. Instead, augment birdseed and nuts with beef fat trimmings, bacon rinds, apples, grapes, potatoes, peas. And, cheese, as this bird is eating. You can also offer moistened pet food. As in summer, don’t allow foods to spoil and don’t leave leftovers out overnight if you want to avoid unwanted nocturnal critters. Be sure to grate or cut food into tiny pieces. No junk food!

Cedar Waxwing and berries

Will this Cedar Waxwing get drunk? (Patricia Holroyd / EOL; cc by 3.0)

Have you heard the one about the drunk bird? It sounds like a joke’s coming next, but there really are birds who get drunk from eating too many fermenting berries. That seems funny, but sometimes it isn’t. Like many DUI drivers, FUI birds are simply too drunk to fly right and many die from crashing into things. They behave pretty much like humans who over-imbibe: They walk in circles. They fall over and lean against things for support or bring their wings to the ground to hold themselves upright. They vomit. They probably suffer morning-after headaches. Here’s a good story about a drunk Cedar Waxwing, including useful tips about how to care for a drunk bird, and good photos, too.

Bird feeder unvisited

Beautiful bird feeder, where’s the action? (Faiyaz Hawawala / Wiki; cc by-sa 3.0)

Where did they go? Why do birds sometimes disappear (or mostly so) from our feeders? Because nothing beats fresh food, like berries on a bush and seeds still clinging to flower heads. So even in winter, the number of visitors at feeders may be low as long as fresh foods are available. No matter how elaborate and well-filled our feeders may be, birds may scarcely give them a glance when there’s food available at its source.


Sleeping and resting

Sleeping Mallards. (Roland zh / Wiki; cc by-sa 3.0)

Where do birds go to sleep? Usually they go where they’ll feel safest within the same area they spend their waking hours. Some who nest on the ground also sleep there in dense cover. Others sleep hidden in trees where they can also feel the vibrations of climbing predators in time to escape. Cavity-nesting birds sleep in tree holes, chimneys or birdhouses. Many water birds sleep in or close to water.


Flamingos. (© Gareth Leung)

Some birds sleep while standing on both legs or, like Flamingos and other water birds, on one leg.  Why just one leg? Theories abound, but a commonly accepted one is that it conserves body heat. A bird’s legs receive three times as much blood per heartbeat than their major muscles do. That’s a lot of warmth to hold close to the body. In winter, many other bird species also tuck one leg while sleeping or awake.


Laysan Albatross (Phoebastria immutabilis). (Forest and Kim Starr / Wiki; CC)

Some birds are thought to take short naps while flying. Laysan Albatrosses spend almost their entire lives in flight, sleeping up there, as well. Swifts mate, eat and bathe while flying, and likely sleep while in flight, too — radar planes have detected them several thousands of feet high at night.

Swainsons Thrush

Swainson’s Thrush (Catharus ustulatus). (Jeff Whitlock / EOL; cc by-nc-sa 2.0)

Birds must stay alert to survive, so how do they rest? They do it in short bits — sometimes only a few seconds long — whether napping by day or settling in for the night. Some switch between sleep and drowsing with their eyes half-closed so they can still see. Some who migrate long stretches, like the Swainson’s Thrush, sleep in flight by allowing half their brain to sleep, while the other half keeps its eye open to stay alert — and aloft!


Singing, calling, behavior

(Ernst Vikne / Wiki; cc by-sa 2.0)

Most diurnal (daytime) birds sing only when the sun’s up. But British researchers studying city-dwelling European Robins discovered they’re singing at night. Scientists have long thought streetlights confuse birds into thinking it’s day, but it turns out noise has a greater impact. As the daytime noise level in cities rises, the number of birds singing at night increases. It seems the birds are trying to be heard.

Red-eyed Vireo

Red-eyed Vireo (Vireo olivaceus). (Laura Gooch / Flickr; cc by-nc-sa 2.0)

Why do birds sing and call? For many reasons: To define territory, attract mates, warn of predators, stay in touch with one another, announce the finding of food or to beg to be fed. Winter Wrens sing at 10 times the power of a crowing rooster. The Brown Thrasher can know more than 1,100 distinct songs. The male Western Sandpiper sings while performing courtship display-flying. The Red-eyed Vireo sings 20,000 songs a day!

Song sparrow

Song Sparrow (Melospiza melodia). (Len Blumin / Flickr; cc by-nc-nd 2.0)

Birds sing more in the early morning and at dusk for a reason. That’s when air is typically more still and the way it carries sound waves makes them clearer. There are also fewer competing background noises. Even birds who are heard singing during the day will tend to sing more at dawn and dusk.


Nestlings. (Rick Pawela / Flickr; CC)

Do birds abandon their babies if we touch them? Experts say no — once eggs have hatched, the parents’ drive to nurture their offspring outweighs their fear of human scent. That is, unless the nest is repeatedly disturbed. So, if you’re watching nestlings, it’s best to peek at them only when the parents are away.

Finches on feeder

House Finches, American Goldfinches on thistle feeder. (WW)

Do you see frenzied activity at your bird feeders before a storm? That’s because birds have a special receptor in their middle ear telling them to hurry up and take shelter. Called the Vitali organ or Paratympanic organ, it helps with their hearing and balance, but it’s also a built-in barometer. When air pressure starts falling, signaling a storm ahead, birds change their foraging patterns, social interactions and times of activity. Bats are the only mammals having a Vitali organ (named after its discoverer, Giovanni Vitali, an anatomist). Although we humans can detect some pressure changes, birds can do it to a remarkable extent.


Purple Martins on high wire. (WW)

We’ve all seen birds perched like this, sometimes by the hundreds. Scientists think they do it because high wires are good resting places and offer a good view. Sitting close together also makes for easy communication. Have you noticed that, except for the occasional nonconformist, they sit facing the same direction — into the wind? That’s probably because sitting with their backs to the wind would ruffle their feathers and it’s also easier for them to take off into the wind.

Pileated woodpecker pair

Pileated Woodpecker pair (Dryocopus pileatus). (Rodney Campbell / Flickr; cc by 2.0)

Different birds have different “domestic” lifestyles. Some pair up only through the current nesting season. Others stay together long term, until one partner dies. Some are polygamous and mate with several partners to ensure they spread their genes around. Others are monogamous and stay together for life, until one of them dies. The health of their mates is important to birds and with some species a pair may part company if one becomes frail. Blue Jays, Barn Owls, Bald Eagles, Canada Geese and Pileated Woodpeckers are some of the birds who mate for life.


Anatomy, feathers, grooming

Robin bath

Young American Robins take a bath. (WW)

“Just washed my feathers and can’t do a thing with ’em.” Many bird species bath regularly. If possible, even in winter! They do it to keep their feathers clean, wash off parasites and cool their bodies on hot days. After bathing, some birds use oil from a gland under their tail feathers to coat their feathers.

Great Horned Owl tufts

Great Horned Owl (Bubo virginianus). (Tony Hisgett / Wiki; cc by 2.0)

Some owls have long feathers sticking up on their ears. Called ear tufts, they’re a distinctive addition to a bird’s appearance, but have nothing to do with the ears or hearing. Scientists don’t really know the purpose of ear tufts — perhaps they’re used for subtle communication, signaling or recognition. About 50 species of owls have them.


Habitat, environment

(Vicki’s Nature / Flickr; CC)

Birds and other wildlife suffer in winter if they don’t have access to water — it can be more vital than food. Check your birdbath daily, because water evaporates faster in cold weather. Is your birdbath heated? Access to liquid water is a challenge in freezing temps. This Mourning Dove looks like he needed a long, satisfying drink. As you can see, what he found was ice. If possible, place a heated birdbath close to the ground so all animals can reach it.


(© Jerry Friedman / Wiki; cc by-sa 3.0)

When snow is covering the ground, how do birds cope? How can they find food? Ground-feeding birds look for bare spots and mine them thoroughly for seeds, insects. Birds search crevices in woodpiles and rock piles, cling to old flowers and pick at the heads. If necessary, they try scratching through the snow. Their situation grows ever more challenging when snow is deep and long lasting.


No, not dead! This Spotted Woodpecker is crouching down to eat snow. (Brian Fuller / Flickr; cc by-nd 2.0)

No, this woodpecker isn’t dead. He’s crouched down, trying to eat snow. It’s a struggle for birds to find liquid water when everything’s frozen. Covered with layers of fluffy, insulating down, they’re pretty prepared for winter’s cold temps. But finding water and fatty foods for energy — and plenty of it — is key to their survival. Small birds can’t peck through frozen ground and ice. Birds’ ability to fly farther south helps them out and we sometimes see unexpected species of birds at our feeders. (The woodpecker shown here is the Great-spotted (Dendrocopos major). They inhabit Europe and northern Asia.)


(Karelj / Wiki; PD)

Are cats poaching at your bird feeders? Place feeders in the open, away from shrubs and other hiding places. Try putting a wide circle of short wire fencing around feeders. This works well even when feeders are near shrubs — by placing the fencing just in front of the shrubs, cats may hide, but must jump over the fence, which rustles the foliage and alerts the birds.

Cat in leaves

(© Zyfranklin)

Cats can hide very well — sometimes by remaining motionless in plain sight. Hanging a bell on a cat’s collar doesn’t help — a stalking cat moves too slowly to ring the bell, and when he pounces, the ringing comes too late.

Cat looking out

(Robert Linder / Stock.xchng; CC)

If a neighbor’s cat is a problem, the solution may be as simple as asking them to keep their cat indoors. It’s not only safer for birds, but for cats, too: Cats who go outdoors have shorter lives, falling prey to cars, dogs, coyotes, other animals, and diseases, such as feline distemper. They get lost, stolen, poisoned. photo of cat looking out of window by Robert Linder / Stock.xchng