If we look for the champion of champions, it must be the Arctic tern. This is the bird that roves over more of the planet than any other creature. It is the longest distance migrant, and so enjoys more daylight than any other creature. Breeding north of the Arctic Circle, it migrates southwards the length of the world to reach the Antarctic pack ice, 11,000 miles away.

The tern goes far, but surely no bird lives life faster than the hummingbird. The heartbeat of the North American hummingbird has been timed at 1,000 beats a minute -- that's 16 beats a second.

Hummingbirds migrate from the United States to Central and South America to feed on the flowering tropical plants there. Some fly the 500 miles straight across the Gulf of Mexico, an awesome feat of endurance for a bird so tiny.

The peregrine falcon may be the fastest bird on earth. Its dive, or "stoop," on an intended victim has been timed at 180 mph.

The Antarctic Penguins are the deep sea champions among birds, diving to depths of over 1,300 feet, and attaining speeds of nine miles per hour in search of fish and squid. Micro-electronic dive and activity recorders provide a continuous record of the number and depth of dives made, swimming speed and how often it catches food. They reveal that emperor penguins can stay an astonishing 11 minutes under water during a dive. How these birds manage to survive at such depths without incurring physiological problems, such as oxygen starvation and the toxic effect of gases at high pressures, is still a mystery.

The Emperor penguin is better adapted to the cold than any other animal on earth. It is the only bird that can survive the Antarctic icecap in winter.

The highest nesting bird of all is the Himalayan snow cock, which builds its nest at heights of more than 15,000 feet. The Alpine chough is not far behind; it is at home all year round at heights about 10,000 feet in the Himalayan Mountains.

Choughs are perfectly adapted to the cold and thin air, hopping around looking for food. A mouse would barely be able to crawl under such low pressure conditions. In Europe, they beg food from skiers at the tops of ski slopes.

A bird that winters at perhaps the highest altitude is the giant coot in Peru, Chile, Bolivia and Argentina. Life at high altitudes is especially harsh in winter, when temperatures drop many degrees below zero and all waters freeze. But the giant coot, instead of migrating to lower altitudes, congregates in small flocks around the widely scattered volcanic springs. There they find pools that are kept clear of ice by the warm water and provide them with enough food to see them through until spring.

Another bird that endures the extremes of winter instead of migrating to warmer places is the common poorwill in North America. This bird survives the period of cold weather and food shortage by going to sleep. During hibernation, the poorwill's body temperature drops and it uses up very little energy. This means it can survive for 100 days on the same fat reserves that would sustain it for only 10 days when awake.

The native Indians call this bird "the sleeping one, "because when in hibernation the bird goes into a torpor from which it requires several hours to wake up. This inability to respond quickly to danger is one of the main disadvantages of its unusual behavior, but the poorwill is so effectively camouflaged that it usually remains undetected in the sheltered crevices where it chooses to hibernate.
 

The flamingos are so highly specialized and precisely adapted that they fit easily into this particular habitat. They sift the murky waters of the lakes for tiny invertebrate prey that they filter out with their peculiar downward curving bill.

The flamingos build their nests from the muddy sediment in the lake. They pick up mud and stones to form circular nest mounds; the huge breeding colonies look like miniature citadels of mud. On top of these mounds they place their single white egg.

A sand grouse could be described as the busiest eater in the bird world. It needs to find several seeds every second to get enough food to survive. To sustain these sorts of feeding rates, it exploits areas with superabundant seed banks. The grouse peck up each seed individually, and look like little sewing machines when feeding.

Each bird will consume between 5,000 and 80,000 seeds a day. Some seeds are so small that it takes 5,000 to make up just one gram.

The biggest weight gain in a bird -- relative to its size -- may be by the sedge warbler, which can go from 11 grams (two fifths of an ounce) to 22 grams in the few weeks prior to its migration from Europe to South Africa. This gives it enough fuel to fly for 90 hours without rest.
 

Wandering albatrosses nesting on small Antarctic islands circle the globe during their migrations. A bird ringed at Kerguelen Island in the southern Indian Ocean and recovered in Chile, traveled in less than 10 months at least 8,100 miles, and perhaps as much as 11,200, miles by drifting with the prevailing winds.

Just how tradition-bound birds can be is illustrated by the albatross. Since the 1930s, only two pairs have nested on Inaccessible Island in the Pacific, whereas a few thousand pairs breed on the neighboring Gough Island. The albatrosses are so site specific that the two pairs on Inaccessible Island will not fly over and mate with the ones on Gough, even though they will fly hundreds of miles for food. Young born on Inaccessible, returning to the island and looking for an albatross to display to, cannot find a bird to show them where to land. As a result, they land amongst the trees and don't even make it to the albatross nesting site. Decoys are to be used to attract the albatrosses to a nesting site.
 

The murrelet lays its eggs in burrows. The chicks hatch and, for the first day, feed off their egg sac. Then, at dead of night, two days after the chicks hatched, the parents fly out to sea, calling their young to follow with a continuous sparrow-like chirping. The fluffy black and white chicks, still unable to fly or feed on their own, pour in a living flood down the hillsides. They evade killer mice and insomniac ravens, and hurtle for the surf like downy toys on clockwork legs, heeding the call of their parents. They don't stop when they reach the water, but pursue their parents into the breakers and swim five miles out to sea. Once here they will continue to be fed for a few more weeks until they can fly.

The most precocious chick in the world could well be the offspring of the torrent duck, which is quite at home amongst the fast-flowing mountain rivers and waterfalls of the Andes. The birds breed amongst the rocky banks of the rivers and their chicks take to the foaming water almost immediately. The birds negotiate waterfalls and white-water rapids with ease. They clamber on to rocky ledges behind waterfalls to forage among the vegetated rocks, feeding unconcernedly as the water cascades over them.

The passenger pigeon, a North American species abundant in the 19th century, may have been the commonest bird that has ever lived on earth. However, its superabundance did not save it from extinction at the hand of man.

The beautiful blue Spix's macaw of the Brazilian rainforest is the loneliest and, due to man's actions, probably the rarest bird in the world. Spix's macaw lives exclusively in gallery woodland in Brazil's dry scrubland; the only good example of this habitat is now found along the San Francisco River. By the 1980s, virtually all of the birds had been trapped and sold as pets. Until a few years ago, only one solitary bird existed in the wild. A conservation project has since boosted numbers.

The elephant bird was a huge flightless ostrich-like bird, about nine feet tall with thick powerful elephant-like legs. It probably grazed on shrubs and grasses, and lived in Madagascar until it became extinct 300 years ago. Some of its eggs are still found: they are the largest known.

The giant egg, weighing 18 pounds, is the equivalent of 183 chicken eggs, or 12,000 hummingbird eggs.
 

The storm petrel is a small seabird that also lays relatively massive eggs -- they weigh about a quarter of its own body weight.

Bar-headed geese may be the highest fliers of the bird world. Breeding in Tibet and wintering in India, they fly at over 18,000 feet to get through the Himalayan passes. Demoiselle cranes, which breed in Siberia, achieve similar heights on their migration route across the Himalayas to winter in India. Godwits and curlew have been seen migrating south from Everest at 20,000 feet. Radar has picked up birds -- possibly dunlin or knot -- flying at 23,000 feet between Scandinavia and Britain.

Most bird records are set on the wing; the emu can boast a rather unusual record - as the world's furthest walking bird. It cannot fly, so must walk during its migrations. The pattern of rainy and dry seasons in Australia forces the emu to follow rain clouds in search of water. Emus are believed to respond to the low frequency sound of raindrops hitting the ground. Nevertheless they often have to walk as far as 320 miles following the rain clouds.

Few birds can be as fussy about where they live as the small Kirtland's warbler. It breeds only in a small area where jack pine forests grow on a particular type of sandy soil. This soil is important because the warblers embed their nests in the ground among long grasses, and heavy summer rainstorms would flood them if the water did not drain away quickly.

To make things even harder for themselves, the warblers only breed among trees that are between 10 and 20 years old. Such new stands of trees follow after fire has swept through a mature stand of pines, releasing their seeds and allowing them to germinate. The birds start to nest in the area when the pines are young.

The Kirtland's warbler is also highly specialized in its feeding requirements. It takes only seeds of the jack pine, which are released during forest fires. Forest fires are therefore a natural and essential phenomenon for the survival of this bird.

Such a preference for a particular stage in a habitat's growth is probably unique in birds. But it also played a large role in the decline of the species. Wildfires once provided abundant habitat for the warblers. But today wildfires are controlled and lumbering practices have changed. The warbler now only breeds in a protected area in north-central Michigan, where controlled plantings and fires produce the habitat it requires.

One bird thrives in perhaps the oddest habitat of all.

Wildlife is often a casualty of war. Not so the Japanese white-naped crane. The tension between North and South Korea has brought unrest to the region for years. But for the cranes migrating from Japan to Chinese breeding grounds, the three-quarters of a mile wide Demilitarized Zone (DMZ) between North and South Korea is a haven. The arable fields in the DMZ are an important stopover site for the cranes; in the fields, the cranes replenish their reserves for the second leg of their migration.

Some birds have developed exquisite skills with which to conceal their nest in its setting. The golden headed cisticola, a type of Australian warbler, is the most skilled tailor in the bird world. It uses thread from spiders webs to stitch living leaves together to make an almost perfectly camouflaged dwelling.

The Volegkopf bowerbird in the forests of New Guinea spends nine months building its spectacular nest, said to be the most beautiful architectural creation in nature. Then he decorates it with shiny treasures, such as the iridescent wing cases of beetles and flowers.
 

Guanay cormorants, living on the Peruvian coast, are far and away the world's biggest grossing bird. They have been named the "billion dollar bird" because the huge deposits of their droppings, or guano, which collected under the cliffs where they packed together in nesting colonies at densities of 12,000 nests per acre. Guano once made a highly prized fertilizer, and supported an industry.
 

In South America, one humming bird has a beak twice its length. The uniquely shaped bill is designed to precision drill a hole at the base of a flower. But it can't help itself; even when it finds a flower with a short stem it could enter legally, it still breaks in.

One of the most far-carrying songs of any bird is the deep boom of the male kakapo, which reverberates through the night air in New Zealand and can be heard as far as four miles away.

The longest tail in proportion to the size of the bird is that of the ribbon-tailed astrapia, found in dense tropical rainforests of New Guinea. The long white streamers that trail behind the male in flight, have evolved purely to impress females.
 

Outstanding in the world of birds with respect to individual plumage variation is the ruff. These birds are unique in that all males have their own plumage pattern -- no two birds are alike. The birds hardly call at all. The plumage is their signal of identity and individuality.

At the opposite end of the scale, the woodcock is one of the best camouflaged of all birds. As soon as it sits down, provided it remains absolutely still, it disappears completely into the background.

What benefits a bird to be a champion? Living higher, flying faster, diving deeper certainly gives a bird the edge over competitors. It provides it with a wider range of life options, a bigger area in which to nest and find food. But it doesn't necessarily follow, for example, that speed of flight as it goes in for the kill gives the peregrine falcon total mastery of the skies.

We don't look up and see the skies above us thick with peregrines. Other environmental factors -- even without man's destructive intervention -- take over to limit even a winning bird's population. If a bird's numbers grew too fast and far, its habitat might not have enough food to support it.

And then what about the birds they would seem to be cut out to be losers -- nondescript birds that have nothing in their favor, neither an opera star's singing repertoire, nor a supermodel's finery. They have neither speed nor hunting skill. So what are they still doing on the planet? Perhaps they are here because they are the ultimate winners.
 

While the starling has striking, spotted iridescent plumage, the sparrow must be one of the dowdiest, undistinguished of all birds. Yet it may also be the most successful bird to live close to man. What this otherwise drab and unremarkable bird has in its favor is its audacity, its gregariousness, and its street urchin attitude, which allows it survive in the tawdriest back alley.

Both species live confidently and comfortably close to man, in cities, towns and suburbs, nesting on and in buildings; they occur in large numbers throughout their range. In the evenings, starlings form massive noisy roosts in town centers.

Then there are the red-billed queleas, seed-eating finches that occur in gigantic feeding flocks of tens of thousands, sometimes millions of birds. The total world population of these small sparrow-like birds is estimated to be in the order of 100,000 million, putting it well in line for the title of the world's most numerous bird. As they travel across the land in search of food, they resemble a huge swarm of large insects, blackening the sky.

Queleas' natural food is the seeds of wild grasses, but their huge numbers mean that from time to time they exhaust their natural food supply. They then turn to cultivated fields, of millet, corn, wheat and rice. The entire flock will descend and work the field like a gigantic lawnmower, stripping it of all its seeds within minutes, doing as much damage as a flock of locusts. Then the massive horde is off again.

The queleas' huge numbers and the devastation they cause has brought them into conflict with local farmers. Some tribes have traditionally harvested queleas for food; but now locals pursue them with much greater force. Queleas' breeding coincides with the ripening of certain grass crops, and breed in massive colonies of up to 10 million nests. Some people have resorted to blowing up the nests with dynamite. But even such extreme measures seem to have little effect on overall quelea numbers.

Sleeker, smarter, stronger species may come and go. The quelea is here to stay.