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Sidestepping the fetid pools where seals had been lying, I scrambled up to the only level part of the island, an area about the size of a tennis court, where Paul Scofield, an ornithologist and expert on the Chatham albatross, and his assistant Filipe Moniz had pitched tents, anchoring them with three-inch-long fishhooks wedged into crevices in the rock.
A few feet away a partly fledged Chatham albatross chick stood up on its pedestal nest, yawned and shook its shaggy wings. Then it flumped down with the stoical look one might expect from a creature that had sat on a nest for three months and had another month or two to go.
Around the Pyramid colony adult albatrosses were landing with a whoosh, bringing meals of slurrified seafood to their perpetually hungry offspring. When one alighted near the tents, Scofield and Moniz each picked up a shepherd's crook and crept toward it.
The bird tried to take off, its wings stretching some six feet as it ran from Moniz. A swipe with the crook, a bleat of protest, and the albatross was apprehended, snagged by the neck.
Moniz cradled the bird, keeping a tight grip on its devilishly hooked bill, while Scofield taped a popsicle-size GPS logger—a tracking device—between its shoulders, spray-painted its snowy chest with a slash of blue for ease of recognition, and released it. He and Moniz were planning to stay three weeks on the Pyramid, and they hoped to deploy the devices on a dozen breeding adults to track their movements at sea.
Scofield, of New Zealand's Canterbury Museum and co-author of Albatrosses, Petrels and Shearwaters of the World , has been studying albatrosses for more than 20 years. To research these birds is to commit oneself to months at a time on the isolated, storm-lashed but utterly spectacular specks of land on which they breed: from the Crozet Islands in the Indian Ocean, to South Georgia in the South Atlantic, to Campbell Island and the Snares Islands in New Zealand.
Scofield has visited most of them. Studying albatrosses is also not without risks. Jury-rigged, the yacht limped to its destination. Scofield and the crew stayed on Marion with other albatross researchers for five months they had planned on only two days while waiting for a ship to pick them up.
Another time, during a ferocious storm in the Chathams, Scofield and his colleagues had to wear safety harnesses bolted to the rock as they slept in their tents, in case a wave washed over their campsite. Albatross eggs and even adult birds were bowled off their nests by the wind, and Scofield observed more than one parent try to push an egg back onto the nest with its bill—a challenge analogous to rolling a football up a flight of steps with your nose.
Scofield and other albatross researchers return year after year to their field studies knowing that albatrosses are one of the most threatened families of birds on earth. All but 2 of the 21 albatross species recognized by the International Union for the Conservation of Nature are described as vulnerable, endangered or, in the case of the Amsterdam and Chatham albatrosses, critically endangered. The scientists hope that the data they gather may save some species from extinction.
Albatrosses are among the largest seabirds. The "great albatrosses," the wandering and royal albatrosses, have the widest wingspans—ten feet or more—of any living bird. These are the birds of legend: the souls of drowned sailors, the harbinger of fair breezes and the metaphor for penance in Samuel Taylor Coleridge's Rime of the Ancient Mariner: "Ah!
A wandering albatross is a "regal, feathery thing of unspotted whiteness," wrote Herman Melville. They look white in flight, but even the wanderers have a few darker feathers on their wings, and many of the smaller species have varying combinations of black, white, brown and gray plumage. Albatrosses are masters of soaring flight, able to glide over vast tracts of ocean without flapping their wings. So fully have they adapted to their oceanic existence that they spend the first six or more years of their long lives which last upwards of 50 years without ever touching land.
Everything about albatrosses underscores the difficulty of eking out an existence in their environment. Unlike penguins, which can hunt for extended periods underwater and dive to great depths, albatrosses can plunge into only the top few feet of the ocean, for squid and fish.
The lengthy albatross "chickhood" is an adaptation to a patchy food supply: a slow-maturing chick needs food less often than a fast-maturing one. Similarly, the prolonged adolescence—around 12 years in wandering albatrosses—is an extended education during which birds prospect the oceans, learning where and when to find food. The chick's nutritional needs cannot be met by a single parent. Mate selection, therefore, is a critical decision, and is all about choosing a partner that can bring home the squid.
Jean-Claude Stahl of the Museum of New Zealand has studied courtship and pairing in southern Buller's albatrosses, which breed on the Snares Islands—a naturalist's El Dorado where penguins patter along forest paths, sea lions sleep in shady glades and myriad shearwaters blacken the evening sky.
In Buller's albatrosses the search for a partner takes several years. It begins when adolescent birds are in their second year ashore, at about age 8. They spend time with potential mates in groups known as gams, the albatross equivalent of singles bars. In their third year ashore, males stake a claim to a nest site and females shop around, inspecting the various territory-holding males. Pairs finally form in the fourth year ashore. Albatross fidelity is legendary; in southern Buller's albatrosses, only 4 percent will choose new partners.
In the fifth year, a pair may make its first breeding attempt. Breeding is a two-stage affair. The breeding pair returns to the same nest year after year, adding a fresh layer of peat and vegetation until the pedestal becomes as tall as a top hat.
Albatrosses can glide about 20 feet forward for every foot they drop due to gravity but because they are incapable of sustaining flapping flight the need wind to fly and stay aloft. They turn into the wind to gain height, then glide back down for speed and distance. With each sweep it gains an altitude of about 20 meters when it climbs and speeds of 60kph when its speed up, taking advantage of winds slowed by friction near the ocean surface and those going at high speed about five meters up.
Many hurtle downwind; those going uphill weave into the air currents, catching the crosswind and sailing upward with their bellies windward, then turning downward into the breeze, masterfully playing these two great forces of wind and gravity, they make near-effortless progress. But no matter how far they roam albatrosses always return to the islands of their birth to nest.
On land, albatrosses seem out of their medium. They move with an awkward, spatulate-footed, head -wagging gait that cleanly shows their body was designed for flight and walk was an afterthought. Albatrosses can spend months over the open sea without ever approaching land by using winds and air currents to stay aloft with a minimum of effort. Land is an inconvenient necessity for breeding Graceful as angels and tight as leather, all albatrosses Some albatrosses soar on the easterly winds of the Antarctic and stay aloft of seven years, repeatedly circling the globe, dipping down only to feed on fish and squid, and finally landing on small windswept islands after they reach maturity and breed.
For females, when their chick is old enough, they returns to the air. Shy mollymawk Shy albatross annually migrate 10, kilometers between Australia and South Africa.
The northern royal albatross can fly 1, kilometers in 24 hours and the grey-headed albatross can circle the globe in 42 days. All members of a group of grey-headed albatrosses studied by the British Antarctic Survey circled the globe, with three going around the world twice. All in an easterly direction, with one flying 22, kilometers in 46 days.
Grey-headed albatross breed once every two years. Chicks leave the breeding area when they are 18 months old and wander the sea. The yearlong journey of a grey-headed albatross was tracked by satellite with a transmitter. It more or less traveled east with the wind around the globe between 30 degrees and 60 degrees southern latitude between Antarctica and Argentina.
Foraging trips of wandering albatrosses, recorded with transmitters are hundreds even thousands of kilometers long. Some species circumnavigate the globe, traveling kilometers a day at speeds of 80 kilometers per hour. Albatrosses also seem to be able to predict the weather. The birds typically chose their direction 24 hours prior to the arrival of the system, suggesting they can respond to barometric cues.
Albatrosses mate for life. Courting is something that takes place over a long time and is not taken lightly. Potential mates can spend much of their youth and adolescence getting to know each other and spend two years courting. The female not only has to secure a good provider to bring back food from the ea but also find a reliable partner who she can count on to come back while she sits for months with the eggs.
Male albatrosses do a mating dance with their beaks up and wings outstretched. Other males may cut in and try to win the attention of the female, who picks her favorite and acknowledges him by bowing and flapping. Courting pairs bow, gaze and rise on their tip toes, beak to beak. Sometimes they work on nest construction for several seasons before they actually breed.
Waved albatrosses of the Galapagos perform elaborate sequences of gaping, bowing, bill-fencing and sky-pointing, accompanying this with loud screams, moans and sighs. Most albatrosses lay a single egg during the breeding season. Any more than that requires to much energy and attention. Albatross eggs take longer than the eggs of any other bird to reach the hatching stage sometimes more 85 days longer than any other bird species.
Some species lay eggs every two years. Pairs take turns keeping the single egg warm while their partner forages at sea for food, sometimes for weeks, covering hundreds or even thousand of kilometers. If an egg is left alone it quickly gets cold and the embryo dies. If food is o short supply or there is some other problem the chick is often sacrificed so the adults can survive. From an evolutionary point of view this makes sense because it can take four or five chicks to produce one adult.
Royal albatrosses require a year to raise their young, an effort that leaves them exhausted. They need two years to regain their strength to breed again. Chatham albatrosses also build stump-like nests from dirt, rocks, wood chips, feathers and guano. Chicks spend four or five months sitting in the nests while their parents fly great distances in search of food.
Grey-headed albatross chick Albatrosses feed their young a thick concentrated oil that they extract from their prey and regurgitate in the mouths of their young. Between meals the chick converts oil into bone, flesh, and feathers.
The chick grows so much between visits that adults recognize them not by sight, but by voice and scent. Laysan albatrosses nest on Midway atoll west of Hawaii.
Females lay their eggs and hatch their young in the winter. For the first six months of their lives the chicks are entirely dependent on their preants for nourishment, mostly in the form of half-digested squid and flying-fish eggs foraged at sea and regurgitated by their parents. Chicks are 18 inches tall when they are five months old and completely feathered except for their heads.
Grey-headed and Campbell albatrosses nest together on islands south of New Zealand. Parents watch over the young for the first three of four weeks of life. After that time they are left alone, strong enough to fend off attack from skuas and other predatory birds. Laysan albatross feeding chick Some scientists and conservationists step in and help nesting birds, providing food to chicks whose parents had not returned with food and taking away eggs from clumsy first-time breeders who often break the eggs with their big webbed feet.
The first-timers are given an infertile egg while the fertile egg is put in an incubator until it hatches. Breeding success is these places is 72 percent, compared to an estimated 33 percent had humans not assisted. Fledglings of most species weigh nine kilograms or moreup to 50 percent more than adults.
They need the extra fat to tide them over until they learn to feed themselves. Albatross young take a long time to grow up.
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