5/18/2023 0 Comments Albatross wingspanOver the years many less complimentary names have been given to albatrosses, all of them suggesting stupidity. The name is taken from a Portuguese word "alcatraz" originally meaning any large seabird. There may be more competition for food too if fishing increases in the southern oceans. 1 For information see our factsheet Over Fishing.Īnother threat to the future of the albatross is plastic, oil and chemical pollution of the sea. According to a study in 2011, 300,000 albatrosses are killed yearly by long line fishing. Abatrosses and other seabirds can also get caught on the hooks. This still indiscriminately kills untargetted marine life such as turtles (of which 6 out of 7 species are considered threatened) which are tempted by the jelly fish appearance of the bait. This method involves putting out fishing lines up to 100km long from which there are as many as one thousand shorter lines attached with baited hooks. Longline fishing is a method used to catch more expensive kinds of tuna. One of the biggest threats to the wandering albatross is 'long line' fishing. It may circle the globe many times before returning to the breeding ground to look for a mate. Eventually the young albatross launches itself into the wind and glides away over the ocean. As a result, the parents can only breed every other year. The large, fluffy white chick continues to sit in its nest and is fed throughout the whole of the severe southern winter, until the following summer - a period of nearly nine months. At this stage, the chick may be vulnerable to predators such as skuas, who will eat both eggs and chicks if left unguarded. Then the parents leave their offspring alone while they go out to sea and return every 10 days or so to feed it with huge meals. The parents brood their chick for a short time and it is fed daily for the first 20 days with regurgitated squid, etc. The chick hatches after about 78 days, which includes three days for the chick to break out of the shell. The pair usually change over every two to three weeks and lose quite a lot of body weight during each shift. A single egg is laid, white with red spots, and the parents share the incubation, the male doing most of the sitting. Once a bird has found a suitable mate, which may take a few years, they remain together until one of them dies.Ī large, untidy nest is built by both birds, using soil and vegetation to make a cup-shaped mound about 1 metre across and 30cm high. At the end of the performance they point their bills to the sky and scream loudly.Īt the beginning of the breeding season, which lasts from November until July, several males may be seen dancing around one female. The two birds of a pair dance awkwardly around each other, bowing and clattering their bills, with the wings outstretched. The birds gather in large numbers and the males and females perform elaborate and spectacular courtship displays. The breeding grounds are usually on the top of cliffs where the birds can take off easily in the prevailing winds. The albatross is a very long-lived bird but it does not start breeding until it is at least seven years old. Albatrosses seem to like refuse from ships too, flopping down into the water and sometimes following a ship for days, waiting for scraps to be thrown overboard. Sometimes shallow dives are made to catch fish and other creatures below the surface. It swoops down to land on the surface and catches its main prey - octopus, squid and cuttlefish - with its large bill, which can be as much as 18cm in length. The albatross usually feeds far out at sea, alone or in groups. If there are no air currents, the albatross will land on the sea. In this way, the bird progresses in a series of zig-zags. The bird glides down towards the sea on folded wings and when just above the water, it swings sharply into the wind and is blown back up to its original height by the rising air. It can circle the world from the Tropics to Antarctica! Although an albatross often has difficulty in taking off, especially if there is no wind to help it, once airbourne it can fly for long periods. The wandering albatross has a huge home range consisting of the 77 million square kilometres of the southern oceans.
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