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News in IT • Plastic in the ocean named as a deadly threat to albatrosses in the Southern Hemisphere

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Gray-headed albatross

The gray-headed albatross is a large seabird of the albatross family. Distributed circumpolar, nests on isolated islands of the Southern Ocean. It feeds in the sea at high latitudes, enters the south further than other albatrosses. It got its name for the ash-gray color of its head and neck.

1. Appearance

On average, the gray-headed albatross grows to a length of 81 cm. Its head and neck are dark ash-colored. The tops of the wings, chest, back and tail are almost black. The rump, belly, undersides of the wings are white, behind each eye there is a white semicircle. The beak is black, but the extreme top and bottom of the beak are light yellow, the tip is orange-pink. The undersides of the wings are white with a wide black stripe along the leading edge. On the trailing edge of the wing, the black stripe is narrower. In young birds, the beak and head are black, the crescents behind the eyes are indistinct, and the underside of the wing is almost completely dark.

2. Flight

The gray-headed albatross is listed in the Guinness Book of Records as the bird with the fastest horizontal flight. Fastest bird - level flight. In 2004, the speed of such a flight was recorded at 127 km / h, which the albatross withstood for more than 8 hours, returning to its nest on South Georgia Island during an Antarctic storm.

3. Habitat and habitat

The gray-headed albatross breeds in large colonies on several islands in the Southern Ocean. There is a large nesting colony on South Georgia Island. Smaller colonies are found on the islands of Diego Ramirez, Kerguelen, Crozet, Prince Edward in the Indian Ocean, Campbell and Macquarie Islands south of New Zealand, and a number of islands off the coast of Chile. Feeding chicks, in search of prey, it enters the south into the Antarctic belt. Albatrosses nesting on Marion Island in the Prince Edward Archipelago also visit subtropical waters in search of prey.

Young or non-rearing chicks migrate freely throughout the Southern Ocean, going north up to 35 degrees south latitude.

4. Nutrition

Gray-headed albatrosses, unlike other albatrosses, spend more time in the open ocean rather than over continental shelves. On the high seas, they hunt mainly squid, but also eat other cephalopods, fish, crustaceans, carrion and lampreys. Krill occupy a smaller place in the diet of this species, precisely because there is less krill on the high seas than off the coast. Gray-headed albatrosses can dive for prey to a depth of 7 meters, but they do this quite rarely.

5. Reproduction

Build large nests of grass on steep slopes or rocks. Only one egg, incubation lasts 72 days. Research conducted on Bird Island off the coast of South Georgia has shown that parents bring their chicks an average of 616 grams of food every 1.2 days, with a maximum chick weight of about 4.9 kilograms. Chicks tend to lose weight before fledging. They fledge 141 days after hatching, leave the colony and return only after 6-7 years. A few years after its return to its home island, the young albatross begins to breed. At the same time, having successfully raised a chick, the couple rests the next year. Being outside the colony for many years, young albatrosses cover great distances, often circling the Earth several times.

Breeding populations and trends in their development

6. Protection of the species

The IUCN classifies the gray-headed albatross as a vulnerable species, arguing that it is rapidly declining in numbers. This species is found in an area of ​​79,000,000 square kilometers, its breeding area is 1,800 square kilometers, while the number in 2004 was approximately 250,000 individuals. At the same time, 48,000 breeding pairs were found on South Georgia Island, 6,200 pairs on Marion Island in the Prince Edward Archipelago, 3,000 pairs on Prince Edward Island, 7,800 pairs on Campbell Island, 16,408 pairs off the coast of Chile, only 84 pairs on the island Macquarie, on the islands of Crozet and Kerguelen - 5940 pairs and 7905 pairs, respectively.

Numerous studies show that the gray-headed albatross population is declining. The population on Bird Island has decreased by 20-30% over the past 30 years. The population of Marion Island was declining by 1.75% per year until 1992, but now appears to be stable. On Campbell Island, the number of gray-headed albatrosses has declined by 79 to 87% since the 1940s. In general, the number of this species over the past 90 years, 3 generations has decreased by 30 - 40%. In 1997 and 1998, illegal and unregulated harvesting of the Patagonian toothfish Dissostichus eleginoides in the Indian Ocean resulted in the deaths of 10,000–20,000 albatrosses, mostly gray-headed ones. Gray-headed albatrosses die in fishing nets. Also, this species can be affected by a possible reduction in the food supply caused by global warming.

The gray-headed albatross is studied on most of its nesting islands. In addition, Prince Edward Island is a nature reserve, and the Campbell and Macquarie Islands are recognized as UNESCO World Heritage Sites.

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