1. Education

Discuss in my forum

Albatrosses

By , About.com Guide

Laysan albatross - Phoebastria immutabilis

Laysan albatross - Phoebastria immutabilis

Photo © Kevin Schafer / Getty Images.
Albatrosses (Diomedeidae) are a family of large tubenose seabirds that include about 21 species. Albatrosses are pelagic birds that forage over open waters throughout the North Pacific and Southern Ocean. No living albatross species occur in the North Atlantic.

The albatrosses include some of the largest living bird species. The great albatrosses (a group that includes the wandering albatross and the southern royal albatross) have the largest wingspans of any living birds, measuring as much as 11 feet from tip to tip.

Albatrosses have a large, hooked, sharp-edged bill. Like all tubenose seabirds, albatrosses have two tube-like nostrils along either side of their bill. Since albatrosses feed at sea, salt over-consumption is a concern and excess salt must be excreted. Like other tubenose seabirds, special glands located at the base of their bill enable albatrosses to expell excess salt.

Albatrosses have three forward-facing toes (and no hind toes). Their toes are webbed and their legs are strong, enabling them to walk on land.

As a group, albatrosses are highly endangered birds. Of the 21 albatross species, 19 are threatened with extinction. The main threat to their numbers today is longline fishing, a method of fishing that often inadvertanly kills albatrosses and other seabirds that attempt to feed on longline bait and become entanged in lines, injured and ultimately die. Other threats to albatrosses include injesting plastic waste (found floating in the sea) and introduced species in breeding sites, such as rats and feral cats (which feed on albatross eggs). Since albatrosses lay only a single egg each season, egg predation takes heavy toll on albatross populations.

Diet:

Albatrosses feed on fish and invertebrates such as cephalopods and crustaceans. They also feed occasionally on offal and carrion. Some species, such as the black-footed albatross, feed on fish eggs.

Reproduction:

The reproductive nature of albatrosses is such that it makes them vulnerable to population declines and causes them to be slow to recover their numbers. Albatrosses reproduce sluggishly, with pairs producing only one chick per mating season. Additionally, young birds take a long time to reach sexual maturity.

Albatrosses often return to their natal colony to breed (this behavior is known as philopatry).

Albatrosses take part in a variety of courship behaviors including preening, bill clacking, staring and dancing. They form pair bonds that often last the birds' entire lifetime.

The nests built by albatross species inhabiting the southern hemisphere are more elaborate than those built by the albatrosses of the northern hemisphere. Southern hemisphere albatrosses construt nests from grass, peat, feathers and shrubs while northern hemisphere albatrosses nest in scraped-out depressions in the ground.

Habitat:

Most of the 21 species of albatrosses inhabit ranges in the southern hemisphere including the waters of Antarctica, Australia, South Africa and South America. One group of albatrosses, the North Pacific albatrosses, includes species that inhabit regions of the Northern Pacific such as the waters of the Galapagos Islands, the Hawaii Islands, Japan and the coastal waters of California and Alaska.

No living species of albatrosses are permanent inhabits of the North Atlantic, although occasionally vagrant individuals are sighted. Fossil evidence suggests that there were once albatrosses in the North Atlantic but those lineages have since become extinct.

Albatrosses breed in colonies on isolated oceanic islands.

Classification:

Albatrosses belong to the Procellariiformes, a group of birds also known as the tubenose seabirds.

Albatrosses are divided into four groups: great albatrosses, North Pacific albatrosses, mollymawks and sooty albatrosses. There are 21 species of albatrosses alive today, although experts disagree on this number (some classification systems cite only 13 or 14 species of albatrosses while others cite 21).

Explore Animals / Wildlife
By Category
  1. About.com
  2. Education
  3. Animals / Wildlife
  4. Birds
  5. Albatrosses and Petrels
  6. Albatrosses - Diomedeidae

©2013 About.com. All rights reserved.