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Sleep is essential – It is as important to our bodies as eating, drinking, and breathing, and is vital for maintaining good mental and physical health. Sleeping helps us to recover from mental as well as physical exertion. During sleep, most of the organs, especially muscles, stop functioning. Can birds sleep while flying? Which birds sleep while flying?
Let’s find out which birds sleep while flying and why there are birds that sleep during their flights.
Bird that Sleeps While Flying – How Do Birds Sleep During Flight?
A paper by a group published in Nature Communications in 2016 tracked frigate birds over a period of a 10-day flight, to find out how these birds sleep. They performed electroencephalography, or EEG, where researchers can record the electrical activity of the brain, on the frigate birds as they flew on their long-distance trips. They found two phenomena involved – USWS and REM.
- Unihemispheric Slow-Wave Sleep (USWS), allows one half of the brain to enter into a deep sleep while the eye corresponding to this half is closed and the other eye remains open. Unihemispheric sleep allows an animal to get some rest, while also allowing it to maintain awareness of its surroundings. In fact, dolphins also use this technique to avoid drowning while they rest.
- In mammals, Rapid Eye Movement (REM) sleep can last for several minutes. For birds, and especially flying birds, REM sleep lasts for only a few seconds. Even then, REM sleep is crucial for proper brain functioning. Bursts of REM sleep involve complete loss of muscle tone. The resulting loss of muscle tone caused the heads of the birds to dip during flight, but amazingly it doesn’t affect their flight patterns.
Which Birds Sleep While Flying?
These are the birds that sleep or take short naps during their flights.
1. Eurasian Blackbird
The Eurasian Blackbird, also known as the Common Blackbird in its native Europe and Asia, is a common thrush with very basic black plumage, with an obvious orange eye-ring and bill. They are found throughout most of Europe and parts of southern Asia.
Considered permanent residents in much of their range, particularly in western Europe and southern parts of their range. Eurasian populations further north typically do migrate southward or westward for the winter, with some birds overwintering as far away as northern Africa or far southern reaches of Asia.
2. Peregrine Falcon
Peregrine falcons are quick, large predatory raptors. The falcon’s strong, sharp yellow talons allow it to capture other birds, even while in flight. Peregrine falcons can be hard to identify because of their quick flight and camouflage coloring. The wings and tail are bluish-gray, while the back and head are a darker brown. Sometimes the cheeks can have a dark brown tear-shaped mark. The bird’s chin and neck are white, and each eye is surrounded by a yellow circle. Dark-brown bars run across its white chest.
Peregrine falcons are global birds. They are found on every continent except Antarctica. Peregrine falcons can travel long distances, sometimes between continents, to get from their wintering grounds to their breeding grounds.
Frigate birds are about the size of a chicken and have extremely long, slender wings, the span of which may reach to about 2.3 metres (nearly 8 feet), and a long, deeply forked tail. Frigatebirds are the only seabirds in which the male and female look strikingly different. Females may not have the males’ bright red pouch, but they are bigger than males.
The Magnificent Frigatebird spends most of its life flying effortlessly over the ocean. It rarely lands on the water even though it has webbed feet, because unlike other seabirds it lacks waterproof feathers. The frigatebird is sometimes called the “man-o-war bird” because it harasses other birds until they regurgitate recently captured food, which the frigatebird snatches in midair.
Sandpipers have long bodies and legs, and narrow wings. Most species have a narrow bill, but otherwise the form and length are quite variable. They are small to medium-sized birds. The bills are sensitive, allowing the birds to feel the mud and sand as they probe for food. They generally have dull plumage, with cryptic brown, gray, or streaked patterns, although some display brighter colours during the breeding season. Most species nest in open areas, and defend their territories with aerial displays.
Sandpipers are more geared towards tactile foraging methods than the plovers, which favour more visual foraging methods, and this is reflected in the high density of tactile receptors in the tips of their bills. These receptors are housed in a slight horny swelling at the tip of the bill. The sandpipers have a cosmopolitan distribution, occurring across most of the world’s land surfaces except for Antarctica and the driest deserts. A majority of the family breed at moderate to high latitudes in the Northern Hemisphere, in fact accounting for the most northerly breeding birds in the world.
Swifts are very fast fliers and spend most of their lives in midair. They eat, drink and mate while flying, only stopping to raise young. They even take their baths in flight by dipping in a water source briefly. It’s estimated they fly more than 500 miles each day. Chimney swifts are small birds that look somewhat like swallows and are sometimes mixed in with flocks of swallows. They are often referred to as “flying cigars” because they look like fat cigars with wings flying high above us!
Do birds sleep when flying long distances?
Wearable brainwave recorders confirm that birds do indeed sleep while flying, but only for brief periods and usually with one-half of their brain. We know several bird species can travel vast distances non-stop, prompting speculation that they must nap mid-flight.
How long can birds fly without stopping?
A bird might be able to stay aloft 6 hours at 15 mph (maximum endurance, covering 90 miles) or 5 hours at 20 mph (maximum range, covering 100 miles). Birds can also choose to maximize speed, as when being chased by a predator or racing to defend a territory. Or they can choose some compromise between speed and range.
Quiz on Birds
Sleep is essential and is as important to our bodies as eating, drinking, and breathing. It is vital for maintaining good mental and physical health. But there are a few varieties of birds that sleep while they fly. They sleep only while on rising air currents which allow them to gain altitude and keep them from falling in the water during the short 10-second bursts of total sleep they grab while flying.