Albatross

views updated May 18 2018

Albatross

Flight and navigation

Salt regulation

Courtship rituals

Care of the young

Conservation

Resources

Albatrosses are large, long-lived seabirds in the family Diomedeidae, which contains about 24 species in four genera. They are found primarily in the oceans of the Southern Hemisphere. Albatrosses are superb fliers, and may be found far from land, soaring with their wings set in a characteristic bowed position. Together with petrels, shearwaters, and fulmars, albatrosses are grouped in the order Procellariformes, which includes hook-billed sea birds commonly known as tubenoses. The extremely large nostrils on top of the bill lead to a pair of internal tubes, connected to a highly developed olfactory center in the brain. Thus, unlike most other birds, albatrosses possess a keen sense of smell; some biologists think that albatrosses can locate other individuals, food, and breeding and nesting areas by smell alone.

Flight and navigation

Albatrosses in flight are soaring birds, floating on the air for extended periods without flapping their wings. They have the greatest wingspan of any bird; the wingspan of the wandering albatross (Diomedea exulans ) may reach 12 ft (3.7 m). The slender wings of albatrosses have a large aspect ratio, that is, a high ratio of wing length to wing width. This characteristic minimizes drag (air resistance) during flight because the area at the tip of the wing is relatively small compared to the overall wing length. In addition, since albatrosses are large, relatively heavy birds, the amount of load on the wing is rather high. In fact, it is thought that albatrosses are close to the structural limits of wing design. In spite of this, albatrosses can soar extremely well, even in windless conditions, using slight updrafts of air created by waves on the water surface.

While albatrosses are remarkably graceful in the air, they are ungainly on land and on the surface of the water, to which they must descend to feed on fish and squid. To become airborne again, albatrosses must run into the wind across the surface of the water or land, until they can hoist themselves aloft. This ungraceful take-off, and their clumsy landings, are the reasons the Laysan albatross (D. immutabilis ) of Midway Island was dubbed the gooney bird by servicemen during World War II.

The navigational powers of albatrosses are impressive. They often spend many weeks at sea searching for food, well out of sight of land and obvious geographical landmarks. Some 82% of Laysan albatrosses transported experimentally to unfamiliar sites up to 4, 740 mi (7, 630 km) from their nesting site were able to find their way back. In contrast, only 67% of Leachs storm-petrels (Oceanodroma leucorhoa ) were able to navigate much shorter distances back to their home areaup to 540 mi (870 km).

Salt regulation

Because albatrosses, and indeed all tubenoses, remain out at sea for days or weeks while foraging, these birds must be physiologically capable of drinking seawater without harm. The potentially serious problem of salt/fluid balance is resolved by means of specialized internal glands located at the base of the bill. These glands help regulate the bloodsalt content, which rises following ingestion of seawater, by producing a concentrated, salty fluid, which drips out of the tube on top of the bill. All tubenoses have the habit of sneezing and shaking their head frequently to clear this fluid.

Courtship rituals

Albatross courtship is unique among seabirds, both in its complexity and its duration. Males and females engage in a coordinated dancing display, in which the partners face one another and perform stereotyped and often synchronized behaviors such as bill clappering (in which the bill is quickly opened and closed repeatedly); sky calling (in which the bird lifts its bill to the sky, uttering a call like the moo of a cow); and fanning the wings while prancing in place. These displays are performed in repeating cycles for up to an hour each, numerous times per day. This

behavior allows potential mates to evaluate each others suitability as long-term partners.

Once formed, pair bonds in albatrosses appear to be life-long. After the initial courtship phase is over, the elaborate courtship rituals are much reduced or abandoned altogether in subsequent years. Researchers believe that these displays function more in pair formation than in the maintenance of the pair bond.

Care of the young

Albatrosses produce a single, helpless chick, which in most species requires a full year to leave the nest, longer than any other seabird. This is almost certainly because of the great effort required to collect food for the chick, who may be left alone for periods of 3040 days while the parents forage at sea, and even up to 80 days in the case of the wandering albatross.

To compensate for their lengthy absences, adults feed their chicks a rich meal of oil, procured from their fishy diet. As a result, albatrosses have been called the oil tankers of the bird world: a stream of oil, produced in the adult stomach, is delivered into the hungry chicks bill. In this way the young birds are able to develop a layer of fat to sustain them during long parental foraging trips.

Conservation

In many parts of the range, albatrosses are suffering extensive mortality through their interaction with fishing fleets. The most intense damage is associated with so-called by-catch mortality in long-lining, in which baited hooks are strung out for several kilometers behind fishing boats. Albatrosses are attracted to the bait on the long-lines, but become caught on the hooks and drown. Because albatrosses can live to a great age, take many years to mature, and raise relatively few young, their populations are highly vulnerable to this kind of excess, by-catch mortality. The most critically endangered species are the Amsterdam albatross (Diomedea amsterdamensis ) and the Chatham albatross (Thalassarche eremite. However, at least six additional species are also in serious decline including the Tristan albatross (D. dabbenena ), the northern royal albatross (D. sanfordi ), the black-footed albatross (Phoebastria nigripes ), the sooty albatross (P. fusca ), the Indian yellow-nosed albatross (Thalassarche carteri ), and the black-browed albatross (T. melanophrys ).

KEY TERMS

Aspect ratio of a wing The ratio of a wings length to its width; a higher value indicates less air resistance in flight.

Courtship rituals Stereotyped displays performed by male and female prior to forming a partnership for rearing offspring.

Soaring Sustained flight with wings extended without flapping, characteristic of albatrosses, hawks, vultures, and other birds.

Tubenoses A group of marine birds including albatrosses, shearwaters, petrels, and fulmars, characterized by paired nasal tubes and salt glands.

Resources

BOOKS

Ehrlich, Paul R., David S. Dobkin, and Darryl Wheye. The Birders Handbook: A Field Guide to the Natural History of North American Birds. New York: Simon & Schuster, 1988.

Sibley, David Allen. The Sibley Guide to Birds.New York: Knopf, 2000.

Susan Andrew

Albatrosses

views updated May 21 2018

Albatrosses

Albatrosses are large, long-lived seabirds in the family Diomedeidae, which contains about 13 species . They are found primarily in the oceans of the Southern Hemisphere. Albatrosses are superb fliers, and may be found far from land, soaring with their wings set in a characteristic bowed position. Together with petrels, shearwaters, and fulmars, albatrosses are grouped in the order Procellariformes, which includes hook-billed sea birds commonly known as tubenoses. The extremely large nostrils on top of the bill lead to a pair of internal tubes, connected to a highly developed olfactory center in the brain . Thus, unlike most other birds, albatrosses possess a keen sense of smell ; some biologists think that albatrosses can locate other individuals, food, and breeding and nesting areas by smell alone.

Flight and navigation

Albatrosses in flight are soaring birds, "floating" on the air for extended periods without flapping their wings. They have the greatest wingspan of any bird; the wingspan of the wandering albatross (Diomedea exulans) may reach 12 ft (3.7 m). The slender wings of albatrosses have a large aspect ratio , that is, a high ratio of wing length to wing width. This characteristic minimizes drag (air resistance) during flight, because the area at the tip of the wing is relatively small compared to the overall wing length. In addition, since albatrosses are large, relatively heavy birds, the amount of load on the wing is rather high. In fact, it is thought that albatrosses are close to the structural limits of wing design. In spite of this, albatrosses can soar extremely well, even in windless conditions, using slight updrafts of air created by waves on the water surface.

While albatrosses are remarkably graceful in the air, they are ungainly on land and on the surface of the water, to which they must descend to feed on fish and squid . To become airborne again, albatrosses must run into the wind across the surface of the water or land, until they can hoist themselves aloft. This ungraceful take-off, and their clumsy landings, are the reasons the Laysan albatross (D. immutabilis) of Midway Island was dubbed the "Gooney Bird" by servicemen during World War II.

The navigational powers of albatrosses are impressive. They often spend many weeks at sea searching for food, well out of sight of land and obvious geographical landmarks. Some 82% of Laysan albatrosses transported experimentally to unfamiliar sites up to 4,740 mi (7,630 km) from their nesting site were able to find their way back. In contrast, only 67% of Leach's storm-petrels (Oceanodroma leucorhoa) were able to navigate much shorter distances back to their home area—up to 540 mi (870 km).


Salt regulation

Because albatrosses, and indeed all tubenoses, remain out at sea for days or weeks while foraging, these birds must be physiologically capable of drinking seawater without harm. The potentially serious problem of salt/fluid balance is resolved by means of specialized internal glands located at the base of the bill. These glands help regulate the blood salt content, which rises following ingestion of seawater, by producing a concentrated, salty fluid, which drips out of the tube on top of the bill. All tubenoses have the habit of sneezing and shaking their head frequently to clear this fluid.

Courtship rituals

Albatross courtship is unique among seabirds, both in its complexity and its duration. Males and females engage in a coordinated "dancing" display, in which the partners face one another and perform stereotyped and often synchronized behaviors such as bill "clappering" (in which the bill is quickly opened and closed repeatedly); "sky calling" (in which the bird lifts its bill to the sky, uttering a call like the "moo" of a cow); and fanning the wings while prancing in place. These displays are performed in repeating cycles for up to an hour each, numerous times per day. This behavior allows potential mates to evaluate each others' suitability as long-term partners.

Once formed, pair bonds in albatrosses appear to be life-long. After the initial courtship phase is over, the elaborate courtship rituals are much reduced or abandoned altogether in subsequent years. Researchers believe that these displays function more in pair formation than in the maintenance of the pair bond.


Care of the young

Albatrosses produce a single, helpless chick, which in most species requires a full year to leave the nest, longer than any other seabird. This is almost certainly because of the great effort required to collect food for the chick, who may be left alone for periods of 30-40 days while the parents forage at sea, and even up to 80 days in the case of the wandering albatross.

To compensate for their lengthy absences, adults feed their chicks a rich meal of oil, procured from their fishy diet. As a result, albatrosses have been called the "oil tankers" of the bird world: a stream of oil, produced in the adult stomach, is delivered into the hungry chick's bill. In this way the young birds are able to develop a layer of fat to sustain them during long parental foraging trips.

Conservation

In many parts of the range, albatrosses are suffering extensive mortality through their interaction with fishing fleets. The most intense damage is associated with socalled by-catch mortality in long-lining, in which baited hooks are strung out for several kilometers behind fishing boats. Albatrosses are attracted to the bait on the long-lines, but become caught on the hooks and drown. Because albatrosses can live to a great age, take many years to mature, and raise relatively few young, their populations are highly vulnerable to this kind of excess, by-catch mortality. The most endangered species are the short-tailed albatross (Diomedea albatrus), the Amsterdam albatross (D. amsterdamensis), and the wandering albatross (D. exulans). However, at least five additional species are also in serious decline.


Resources

books

Ehrlich, Paul R., David S. Dobkin, and Darryl Wheye. TheBirder's Handbook: A Field Guide to the Natural History of North American Birds. New York: Simon & Schuster, 1988.

Sibley, David Allen. The Sibley Guide to Birds. New York: Knopf, 2000.


Susan Andrew

KEY TERMS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Aspect ratio of a wing

—The ratio of a wing's length to its width; a higher value indicates less air resistance in flight.

Courtship rituals

—Stereotyped displays performed by male and female prior to forming a partnership for rearing offspring.

Soaring

—Sustained flight with wings extended without flapping, characteristic of albatrosses, hawks, vultures, and other birds.

Tubenoses

—A group of marine birds including albatrosses, shearwaters, petrels, and fulmars, characterized by paired nasal tubes and salt glands.

Diomedeidae

views updated May 21 2018

Diomedeidae(albatrosses; class Aves, order Procellariiformes) A family of large sea-birds that have long, narrow wings, a large head, and a long, strong bill with a hooked tip and tubular nostrils. They have short legs, webbed feet, and a reduced or absent hallux. They are pelagic, often gregarious, and have a powerful, gliding flight. They feed on fish, squid, and other marine animals, coming to land only to nest. Diomedea exulans (wandering albatross) has the largest wing-span of any bird, measuring 3.5 m. There are two genera, with 13 species, found in southern oceans and in the N. Pacific, occasionally wandering into other regions.

Albatross

views updated May 21 2018

ALBATROSS

ALBATROSS, the Yankee-owned ship that brought news of the outbreak of the War of 1812 to William Price Hunt, partner of the Pacific Fur Company, at its Astoria post in the disputed Oregon Territory. Hunt chartered the ship and removed the furs from Astoria to avoid possible British capture, thus abandoning the first American fur post on the Columbia River.

BIBLIOGRAPHY

Ronda, James P. Astoria and Empire. Lincoln: University of Nebraska Press, 1990.

Carl L.Cannon/a. r.

See alsoAstoria ; Fur Trade and Trapping ; Pacific Fur Company .

albatross

views updated May 23 2018

al·ba·tross / ˈalbəˌtrôs; -ˌträs/ • n. (pl. albatrosses ) a large oceanic bird (genera Diomedea and Phoebetria, family Diomedeidae) whose narrow wings may span greater than 10 feet (3.3 m). ∎  a source of frustration; an encumbrance (in allusion to Coleridge's The Rime of the Ancient Mariner).

albatross

views updated May 23 2018

albatross XVII. usu. taken to be alt., by assoc. with L. albus white, of †alcatras pelican, etc. (XVI) — Sp., Pg. alcatraz, var. of Pg. alcatruz orig. bucket of an irrigating water-wheel, corr. to Sp. alcaduz — Arab. al-ḳādūs, i.e. AL-2, ḳādūs pitcher. The changes of sense and form are a serious difficulty.

albatross

views updated May 29 2018

albatross the albatross is traditionally believed to bring bad luck, and the word is used for a source of frustration or guilt or an encumbrance, in allusion to Coleridge's poem about the Ancient Mariner and his shooting of the bird.

albatross

views updated Jun 11 2018

albatross Large, migratory oceanic bird of the Southern Hemisphere famed for its effortless gliding flight. There are 13 species. The wandering albatross has a long, hooked bill, short tail, webbed toes and the greatest wing span of any living bird – 3.5m (11.5ft) or more. Length: 0.7–1.4m (2.3–4.4ft). Family Diomedeidae.

albatrosses

views updated Jun 11 2018

albatrosses See DIOMEDEIDAE; PROCELLARIIFORMES.

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