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HOW DO BIRDS KNOW WHEN TO MIGRATE?

Overall, the birds respond to changing daylength, but weather conditions, e.g. prevailing winds, can modify the timing; ultimately the bird’s hormones drive it to eat lots of food to accumulate enough body fat to migrate.

DO ALL BIRDS MIGRATE?

Most but not all bird species engage in north-south movements each spring and fall; grouse-like birds, owls, woodpeckers less likely to migrate; even within migratory species, some individuals stay north in winter, especially in mild winter with lots of food and cover.

WHY DO BIRDS FLYING IN TIGHT, LARGE FLOCKS NOT BUMP INTO ONE ANOTHER?

This is very difficult to study; possibly a combination of highly developed visual abilities, sensory receptors in the skin to detect vibrations from neighbouring birds’ wings,  excellent motor coordinaton, and strong reflexes are responsible.

CAN BIRDS FLY BACKWARD?

Hummingbirds are masters at it, but other small songbirds, and even large herons, can flutter backwards if pressed to do so.

WHY DO SOME BIRDS FLY IN V-FORMATIONS?

Some species like geese, cormorants and pelicans gain lift from the rising eddies of air currents whirling off the bird immediately ahead of them. This saves energy in the long run.  Formation flying also prevents mid-air collisions among large birds.

WHAT HAPPENS TO EGGSHELLS AFTER BIRDS HATCH?

For precocial birds, they are left in the nest; for altricial birds, they are removed or eaten by the parents for calcium or crushed by the young.

DO BIRDS RECOGNIZE THEIR OWN EGGS AND YOUNG?

Most birds cannot recognize their own eggs.  Parasitic layers like cowbirds and European cuckoos count on this inability.   Gulls sometimes even choose large, fake eggs to incubate over their own.  Most birds accept any birds that hatch in their nests and raptors will accept fostered babies of another raptor species.  Strange-looking young are often rejected by pheasants and ducks.

DO BIRDS HAVE A PENIS?

Only 3 percent of all birds have a penis, flightless birds and waterfowl among them; most have a grooved papilla-like organ down which the semen flows.

DO BIRDS EVER LAY UNFERTILIZED EGGS?

Chickens without access to sperm do; occasionally but rarely, members of a wild pair of birds are not synchronized, leading to infertile eggs.

WHY DO MEMBERS OF A PAIR OF BIRDS TOUCH EACH OTHER’S FEATHERS AND BILLS?

Allopreening or mutual grooming is a ritualized form of agonistic behaviour that bridges the gap between aggressive attacks and sexual behaviour.

DO SOME SONGBIRDS SING AT NIGHT?

Mockingbirds and nightingales are famous for this, especially with full moons or artificial light; sometimes unpaired birds do it to attract mates.

WHY DO BIRDS SING SO MUCH AT DAWN?

The dawn air results in the best transmission of songs to defend the territory and/or attract a mate; the poor light is also better for singing than feeding.

DO BIRDS USE THEIR NESTS IN WINTER?

Most birds with woven structures do not use them for anything other than nesting.  Some hole-nesting birds such as owls and tits do use nesting cavities for roosting.

WHY DO BIRDS PLACE GREEN LEAVES IN THEIR NESTS?

Aromatic compounds in the leaves facilitate nest cleaning and help reduce nest-dwelling parasites; green leaves could also indicate ownership of the nest.

HOW DO EMPEROR PENGUINS KEEP THEIR EGGS FROM FREEZING IN THE ANTARCTIC?

They roll the egg onto their feet and a thick fold of skin drops down to keep it warm.

DO ALL BIRDS BUILD NESTS?

Some birds like nighthawks, whip-poor-wills and plovers  simply deposit their eggs on the ground.  Seabirds like auks and murres lay their eggs on cliffs without nesting material. Emperor penguins have no nests

WHO BUILDS THE NEST?

The female plays the most important role in collecting the materials and weaving the nest, but in some species, the male helps too.  Males of crows, herons, and storks do most of the material collection

ARE ALL BIRDS MONOGAMOUS?

Socially about 90 percent of all bird species are monogamous, but recent studies show a high percentage of infidelity in many different kinds of birds.  Copulations with sneaky unmated males and neighbouring males can lead to as much as 50 percent of the young being sired by them

DO ALL BIRDS MATE FOR LIFE?

Most birds return to the territory, not to a specific mate.  Some larger species have very strong pair bonds that can last as long as both birds live, but a small portion do divorce one another

WHY DO BIRDS REMOVE FECAL SACS FROM THEIR NESTS AND DROP THEM INTO SWIMMING POOLS?

They remove them from the babies to keep the nests clean and drop them into water bodies so as to avoid attracting predators to the nest area

HOW DO BIRDS FIND MY FEEDERS?

They are highly mobile and use vocal and visual cues

IS BIRD-FEEDING BAD FOR BIRDS?

Yes and no; some studies have shown  increased reproductive performance with access to feeders; large numbers of birds combined with poor feeder hygiene can lead to disease outbreaks

DO SONGBIRDS EAT OTHER BIRDS?

Omnivorous corvids such as crows, ravens, magpies and jay kill and consume other birds, especially eggs and young; grackles kill sparrows and eat their brains

WHY DO SOME BIRDS EJECT PELLETS?

Birds of prey, as well as other meat-eaters, form pellets of indigestible material, e.g. feathers, fur, bones, chitinous insect parts, and regurgitate them within 24 hours of a meal

WHY DO SOME BIRDS EAT STONES OR GRIT?

Some use it in their stomachs to grind food (larks, doves, etc.) or remove grease (falcons).

Some use stones as ballast for diving (penguins)

DO BIRDS HAVE TEETH?

No, They have hard cornified bills; some grazing or fish-eating waterfowl have lamellae to tear grass or hold slippery fish, respectively; all baby birds have an egg tooth for opening the shell, which is later lost; falcons have a primitive tooth (previously thought to be used to sever cervical vertebrae of prey).

DO BIRDS DRINK IN WINTER?

Many songbirds do so if water is accessible. If not, they will eat snow.

HOW DO BIRDS DRINK?

Most dip their bills and tilt their heads back so that the water trickles down the throat. Doves hold their bills in the water and suck up the water.

WHY DO SOME BIRDS RIDE ON THE BACKS OF DEER, RHINOS, BUFFALO AND OTHER LARGE MAMMALS?

Sometimes it provides a convenient perch, but on most occasions, the birds are feeding on ticks and other insects in the fur.

DO BIRDS USE TOOLS?

While gulls drop clams onto rocks and crows drop nuts onto paved surfaces to be crushed by vehicles, New Caledonia crows fashion hooked tools from leaves and twigs to extract grubs and larvae from cavities. The woodpecker finch of the Galapagos uses twigs, thorns and cactus spines to flush prey from holes.

DO LARGE BIRDS LIKE EAGLES OR OWLS CARRY AWAY HUMAN BABIES?

There is absolutely no truth to this old person’s tale. Raptors only attack humans to defend their nests.

WHY DO SOME BIRDS RUB ANTS OR MOTHBALLS OR OTHER ODD MATERIALS ON THEIR FEATHERS?

Some songbirds do this to rid the plumageof ectoparasites.

WHY DO SOME LARGE BIRDS SPREAD THEIR WINGS ON SUNNY DAYS?

Vultures do this to gather the sun’s rays for thermoregulation, but cormorants and similar water birds lift their wings to drain the water from their hollow wing feathers.

WHY DO BIRDS FLOP ABOUT IN THE DIRT?

The dust helps to clean off parasites from their feathers.

WHY DO BIRDS NOT FALL OVER WHILE SLEEPING ON A PERCH?

Their feet have tendons that lock them in a gripping position

WHERE DO BIRDS GO AT NIGHT?

Most birds roost or sleep in dense cover or cavities in trees and buildings; water birds, sometimes in mixed groups,  roost in their element, but some in trees; chicken-like birds on the ground or in trees

WHY DO SMALL BIRDS MOB BIRDS OF PREY?

Small songbirds of various types flock together to harass hawks and owls to drive them out of the area; crows especially mob and chase owls in the daytime to ensure their safety while roosting at night

DO BIRDS MAKE NOISES OTHER THAN WITH THEIR VOICE-BOX OR SYRINX?

A number of birds like mourning doves and goldeneye ducks make whistling nposes when they take off.  Woodcocks make twittering musical sounds with stiff outer wing feathers and common snipe make a winnowing sound with rigid outer tail feathers

WHY DO WOODPECKERS DRUM ON METAL ROOFS, CHIMNEY FLASHING, DRAINPIPES, AND TV ANTENNAS?

Drumming is used to scare away intruding males and attract mates.  Metal objects can maximize its volume

DO ALL BIRDS SING OR CALL?

Almost all do.  Adult brown pelicans and  magnificent frigatebirds are mute, while adult turkey vultures and double-crested cormorants only issue grunts. Virtually all baby birds can be noisy

DO BIRDS TASTE THEIR FOOD?

Much better than we originally thought, but they have considerably  less numbers of  taste buds than mammals

WHY DO CAGEBIRDS ACT SO ERRATICALLY IN THEIR CAGES PRIOR TO IMPENDING EXTREME WEATHER, FLOODS, TIDAL WAVES, ETC?

They are thought to be able to perceive infrasounds, i.e. extremely low frequency sounds, produced by these phenomena

HOW WELL DO BIRDS HEAR?

Their ears are located under small stiff feathers on each side of the head; average hearing capability ranges from 5,000 hz in songbirds to 30,000 hertz in some owls

DO BIRDS SMELL?

All birds have nostrils or nares, usually on their bills; while it is not their strongest sense, all birds can smell to some degree; the best “noses” are found in turkey vultures, kiwis, and petrels

DO BIRDS PERCEIVE COLOUR?

Being so brightly coloured, birds actually have four visual pigments, whereas humans only have three; owls can also perceive colour, but less so due to their nocturnal lifestyle

HOW MANY EYELIDS DO BIRDS HAVE?

They have one upper and one lower, plus a third one called the nictitating membrane to cleanse and protect the eye.

HOW WELL CAN BIRDS SEE?

Due to several adaptations, their visual acuity is around three to four times better than that of humans; they may have greater sensitivity to movement; owls can see just as well during the day.

HOW CAN SEA BIRDS SURVIVE IN SUCH A SALTY ENVIRONMENT?

Sea birds as well as species in arid environments avoid salt overload by ejecting excess salt from special salt glands near their beaks controlled by hormones.

HOW ARE BIRDS ABLE TO ENDURE EXTREMELY COLD TEMPERATURES?

Non-shivering internal heat generation from intake of high energy foods, behavioural modifications such as fluffing out feathers to trap heated air, avoiding wind chill by taking cover, huddling, etc., lowering body temperature and heart rate at night, slowing down blood flow to the extremities, and countercurrent heat transfer from arteries to veins are just some adaptations.

HOW DO BUOYANT DIVING BIRDS MANAGE TO DIVE UNDERWATER?

They have many adaptations including non-hollow bones, removal of trapped air beneath the body feathers, swallowing stones or filling hollow wing feathers with water.

HOW DO BIRDS BREATHE?

It takes two inspirations and two expirations to oxygenate and remove carbon dioxide from the blood for each package of air; a combination of the lungs and several air sacs achieve this bellow-like action; there is no dead-end like in mammals’ lungs.

ARE BIRDS REALLY 'BIRD BRAINS'?

Actually most birds are quite intelligent with large brains relative to body size; they perform well in choice tests and some have incredible short-term memory capabilities to find stored food; cervids, e.g. crows, ravens, magpies and jays, and many parrots are the most intelligent.

CAN OWLS TURN THEIR HEADS 360 DEGREES?

A system of well-developed cervical vertebrae and neck muscles allow an owl to turn its head no more than 270 degrees.

ARE THERE ALBINO BIRDS?

Occasionally albinism, i.e. complete loss of pigmentation, can be seen in most melanistic species. Partial albinism or leucism resulting from partial loss of pigments is more common, being caused by poor diet, trauma to the affected area, or genetic defects.

WHY DO SOME BIRDS HAVE BARE AREAS ON THEIR HEADS?

The bare areas on the heads of some species become more brightly coloured for courtship purposes; vultures and condors lack head feathers to minimize bacterial infection while sticking their heads into bloody carcasses.

HOW MANY BIRDS ARE THERE IN THE WORLD?

James Fisher, a British ornithologist, gave an estimate of 100 billion. More recently, ornithological textbooks make it to be 300 billion.  The number is likely somewhere in between.

HOW MANY DIFFERENT KINDS OF BIRDS ARE THERE IN THE WORLD?

This depends on what book and/or list one consults.  According to BirdLife International, there 9,797 species, of which 1,186 are threatened in some way.

WHY ARE BIRD SPECIES NOT LISTED ALPHABETICALLY IN FIELD GUIDES?

They are listed taxonomically with the most primitive first, e.g. ostriches, loons, and the most developed last, e.g. sparrows

DO BIRD SPECIES HYBRIDIZE?

Some closely related species do interbreed, especially when geographical barriers are broken down by human activities.

ARE NEW BIRD SPECIES STILL BEING DISCOVERED?

Occasionally but rarely a new species is found in a remote region; more often a new species is created when sophisticated genetic techniques along with morphology and behavioural differences indicate that one species should be split into two or more.

HOW LONG DO BIRDS LIVE?

Generally, the larger the species, the longer it lives.  Captive birds usually outlive wild ones.  Most small songbirds do not make it past 2 to 4 years of age.

WHY AM I SEEING LESS BIRDS THAN BEFORE?

Bird populations fluctuate over time due to weather patterns, disease outbreaks, increased predator pressure; local populations are affected by changing land uses; birds requiring specialized habitat are declining

WHERE DO FEATHERS COME FROM?

Only birds have feathers which originate from the skin and once grown, become dead tissue; if a bird loses a grown feather, they will often grow a new one within weeks

WHAT CAUSES THE COLOUR IN BIRDS?

While many colours are caused by pigments, some from heredity and some from diet, reflection and diffraction of light resulting from the structure of feathers is responsible for the colours in some birds

ARE ONLY THE MALES MORE BRIGHTLY COLOURED?

In most species, the male is brightly coloured to attract mates and defend the territory, but in a few species such as phalaropes, the males which incubate the eggs and raise the young are less brightly coloured.

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