Albatrosses: Diomedeidae

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ALBATROSSES: Diomedeidae

CHATHAM MOLLYMAWK (Diomedea cauta eremita): SPECIES ACCOUNTS
LAYSAN ALBATROSS (Diomedea immutabilis): SPECIES ACCOUNTS

PHYSICAL CHARACTERISTICS

The largest albatrosses have wingspans that can exceed 9.8 feet (3 meters). Adults have black backs and white underwings. Their hooked bills are 5.5 to 7.5 inches (14 to 19 centimeters) with a pinkish hue in adults that are raising chicks.

Northern Pacific albatrosses have wingspans of 6.2 to 7.9 feet (1.9 to 2.4 meters). Although all four species have short, black tails, their bodies vary in coloration. One of the smaller birds, the Laysan albatross, has white feathers on its body and dark upper wings while the black-footed albatross is mostly dark brown except for a white patch on its hind end. The eleven mollymawk species vary greatly in coloration.

The two sooty albatrosses have a wing span ranging from 6 to 7.15 feet (1.8 to 2.2 meters). They have the most pointed tails of the family and have mainly dark bills, feathers, and legs.

GEOGRAPHIC RANGE

Albatrosses are found in the northern Pacific Ocean, Galápagos Islands to the coasts of Ecuador and Peru. They are also found in the Southern Hemisphere on coastal waters.

HABITAT

An albatross spends more than 70 percent of its life on the ocean, where it searches for food, rests, and migrates, moves from one part of the world to another. Albatrosses require wind to help them get off the ground, so windswept islands are chosen for breeding sites. Here they build their nests and raise their young for the first months of life. Certain species prefer small, rocky islands on which to build their nests while others choose grassy slopes or plains so that there can be more distance between nesting sites.

DIET

Squid is the favorite food of the albatross. Because many squid glow in the dark, albatross often feed at night. They also eat the carcasses of seals, penguins, whales, and other marine life. In addition to fish, albatrosses consume crabs, krill, seaweed, and small seabirds. Most food is found at the water's surface, though albatrosses have been known to dive and swim underwater for short distances (up to 16 feet [5 meters]) while foraging for food.

BEHAVIOR AND REPRODUCTION

Though quiet while at sea, albatrosses are quite noisy at breeding colonies, where they communicate by wailing, crying, and clattering their bills. There is a definite courtship, rituals associated with mating, among the albatross, ranging from dances and wing displays to "calling" to one another.

Though fighting is not a regular occurrence, the albatross will defend its nest site. Usually a threat display or charging will be enough of a warning, but the hooked bill is useful in damaging eyes and bills if necessary. If approached, chicks and parents will regurgitate, bring up from the stomach, stomach oil and spew it at the intruder, covering him in a waxy substance that can harm feathers. The albatross grooms itself often, and parents are quite attentive to the cleaning of the chicks.

THE RIME OF THE ANCIENT MARINER

In 1798, Samuel Taylor Coleridge wrote a poem titled, The Rime of the Ancient Mariner. The mariner and his crew were visited by an albatross, considered by many to be a sign of good luck. When the mariner shoots the bird, his ship and shipmates are lost, he is blamed for committing a sin by killing a good-luck omen. As punishment, his shipmates hang the dead albatross around the neck of the ancient mariner. This poem popularized the albatross, and led it to become part of slang expression. The word "albatross" is now a figurative expression used to mean "something that hinders or handicaps."

After finding suitable land, the albatross usually builds a bowl-shaped nest and deposits a single egg into it. Albatrosses are monogamous, having one mate, and lay one egg each year. Incubation, the time it takes to warm the egg sufficiently for hatching to begin, lasts anywhere from sixty-five to eighty-five days. Parents take turns sitting on the egg, and both will play a role in raising the chick. Each turn lasts from one to twenty-nine days. Hatching occurs over a period of two to five days. Chicks remain with a parent at all times for the first three months and will fledge, take its first flight, between 120 and 180 days for smaller species to 220 and 303 days for the larger family members.

Albatrosses do not begin breeding until they are between the ages of five and fifteen years. Chicks have a high survival rate because the breeding site has very few land predators. Annual mortality, death, rates for adults range from 3 to 9 percent. The oldest known albatross was still breeding at more than sixty-two years old.

ALBATROSSES AND PEOPLE

Albatrosses were revered by some seafarers as a good luck sign. Others believed that to see an albatross at sea was warning of an oncoming storm. Fishermen depend on the albatross to show them where large populations of fish are located, and the harvesting of chicks (legally and illegally) goes on today. They are hunted for sport as well as food and scientific specimens.

CONSERVATION STATUS

There are not enough data to determine the rate of increase or decline for most species, but albatrosses are not in danger of extinction. Changes in global climate are responsible for the decrease in some species, such as the northern royal albatross. Changing sea temperatures also negatively affect food distribution and availability.

CHATHAM MOLLYMAWK (Diomedea cauta eremita): SPECIES ACCOUNTS

Physical characteristics: Chatham mollymawks weigh in at 6.8 to 10.4 pounds (3.1 to 4.7 kilograms) and is the largest of the mollymawk family. They have a white body, dark gray head, and black upper wing and tail. The underwing is white except for wingtip and small dark patch at base of wing. Their bill is yellow with a dark tip and the cheek has an orange stripe across it.

Geographic range: Chatham mollymawks breed only at The Pyramid, a small rocky area of the Chatham Islands. They rarely stray far from this site, even during the nonbreeding season.

Habitat: Chatham mollymawks build small nests of soil and sparse vegetation on rocky slopes and ledges. These nests usually collapse and must be rebuilt every season.

Diet: They live off of krill, barnacles, and fish. They also scavenge behind fishing boats for bait and other discarded marine life.

Behavior and reproduction: During both threat and courtship, the mollymawk makes shrill buzzing sounds with its open mouth. Chatham mollymawks lay one egg between the end of August and beginning of October each year. Both parents share incubation duties with individual turns lasting no longer than five days. The youngest known mollymawk to breed was seven years old. This albatross mates with one partner for life.

Chatham mollymawks and people: There is no known interaction between this species and humans other than what is generally known about human use of albatrosses.

Conservation status: The Chatham mollymawk is Critically Endangered, facing an extremely high risk of extinction in the wild, because it has only one breeding site. ∎

LAYSAN ALBATROSS (Diomedea immutabilis): SPECIES ACCOUNTS

Physical characteristics: Laysan albatrosses have a wingspan of 6.4 to 6.7 feet (1.95 to 2.03 meters) and weigh 5.3 to 9.0 pounds (2.4 to 4.1 kilograms). They are white in color with black patches at the wrist and elbow. There is a gray patch around the eyes and cheeks. The bill is yellowish orange at the base and fades into pink with a black tip.

Geographic range: Laysan albatrosses live almost exclusively in the Hawaiian Islands. Smaller populations live on the Bonin Islands in the west Pacific Ocean and in the eastern Pacific at Islas Guadalupe, Benedicto, and Clarion.

Habitat: Laysan albatrosses spend most of their time on the water, moving onto land only to breed.

Diet: Squid is the main staple of the Laysan albatrosses' diet, but they also eat fish eggs, fish, and crustaceans, marine life having no backbone. They are not known to follow fishing vessels as is the habit of other albatross species.

Behavior and reproduction: Laysan albatrosses have a wider range of displays than other albatrosses, and their communicative sounds have are distinct from those of other families. The nest is a hole in the ground that is built up around the rim using sand and other available debris. They lay one egg between the end of November and the end of December. Incubation lasts an average of sixty-four days, with parents taking turns, sometimes up to three weeks at a time.

Laysan albatrosses and people: The Laysan albatross is nicknamed the "gooney" and is a common sight in the countries surrounding the north Pacific Ocean.

Conservation status: The world population of Laysan albatrosses is around 607,000 pairs, although some colonies are decreasing due to commercial fishing and high levels of contaminants as well as plastic trash in the water. The species is considered Vulnerable, facing a high risk of extinction in the wild. ∎