Albatross: They are a family of large seabirds that, along with the procelarids, hydrobats, and pelecanoids, are distributed throughout almost the entire length of the Antarctic Ocean, the Pacific Ocean, and the South Atlantic Ocean . They are among the largest flying birds.
Summary
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- 1 Feature
- 2 Food
- 3 Playback
- 4 Habitat
- 5 Source
Characteristic
White or greyish head and neck and white rump and underparts, contrasting with the dark gray or sooty gray back, tail and upper parts of the wings. They have a dark marking near the eye, this usually extends in a list shape, through and behind the eye. The adult has a pinkish yellow bill; lower surfaces of the wings white, with blackish edges, the front ones broad and the back ones narrow. Immature has greyish head and neck, dark or slightly ivory bill; but the underside of the wings have very wide dark edges, with narrow white centers. It is a large seabird (although it is not the largest). It measures 80 to 95 cm in length. The wings reach an extension between 213 and 246 cm. The average weight exceeds 3 kg, some specimens reaching 3.9 kg.
Feeding
They feed on cephalopods , fish and crustaceans , although they are also scavengers and supplement their diet with zooplankton. The importance of each of these food sources in their diet varies substantially from one species to another, and even from one colony to another. Thus, while some species base their diet on squid , others eat a greater amount of krill or fish.
Reproduction
They generally nest on secluded islands. In more continental territories, they are found on headlands with good access to the sea in various directions, such as on the Otago Peninsula in Dunedin , New Zealand . They nest under trees in open forest. The colonies vary from very dense accumulations, typical of the albatrosses of the genus Thalassarche . They have an average density of 70 nests per 100 m², up to much smaller groups with widely spaced individual nests, typical of the Phoebetria and Diomedea genera . All its colonies are on islands that were historically free of land mammals. Albatrosses are very philopatric, that is, they will generally return to their natal colony to reproduce. This trend is so strong that a study showed that the mean distance between the hatching site of the egg and the place where the bird subsequently establishes its own territory is 22 meters. Like many other seabirds, albatrosses follow the K strategy in their life cycle, that is, a low birth rate, offset by a relatively high longevity, delay the time to procreate and invest more effort in fewer young. They have a relatively long life expectancy; most of the species live more than 50 years. The longevity specimen on record was a Northern Ringed Royal Albatross when he was an adult and that he survived for 51 more years, which allows estimating that he could live for about 61 years.
They reach sexual maturity late, after about five years, but even once they have reached maturity, they will not join a couple to reproduce for a long time (up to more than 10 years in some species) and they establish a monogamous relationship for their entire lifetime. If there are significant changes in the sexual proportion of the population, in the absence of males, the social structure can change and a cooperative behavior of incubation and rearing of the chicks by two females can take place and due to their monogamous habits this pairing can be prolonged for years, a very rare behavior in the animal world, especially when there is no relationship or kinship between them. Young non-breeders join a colony before beginning to reproduce,
Great albatrosses spend more than a year caring for the young from laying until it acquires its plumage. They lay a single sub-elliptical egg, white with reddish-brown spots, during the breeding season. The largest eggs weigh 200 to 510 g. If they lose the egg due to predators or by accident, they will not make a new breeding attempt that year. Due to the associated decreased reproductive success of the lifelong relationship, separation from established pairs is very rare among albatrosses and usually only occurs after several years of unsuccessful breeding attempts. Albatrosses care for and protect their young until they are large enough to defend and thermoregulate themselves.
Habitat
It lives in the southern oceans. They generally remain between latitudes 60º S and 30º S. Although some have been recorded off the coasts of Europe and off the coasts of Kenya in Africa . It nests in Chile at Cabo de Hornos , Las Malvinas and on oceanic islands within its range.
