Grey-headed Albatross
Encyclopedia
The Grey-headed Albatross, Thalassarche chrysostoma, also known as the Grey-headed Mollymawk, is a large seabird
from the albatross
family
. It has a circumpolar
distribution, nesting on isolated islands in the Southern Ocean
and feeding at high latitudes, further south than any of the other mollymawk
s. Its name derives from its ashy-grey head, throat and upper neck.
order, along with shearwater
s, fulmar
s, storm-petrel
s, and diving-petrels. They share certain identifying features. First, they have nasal passages that attach to the upper bill called naricorns. Although the nostrils on the Albatross are on the sides of the bill. The bills of Procellariiformes are also unique in that they are split into between 7 and 9 horny plates. Finally, they produce a stomach oil made up of wax ester
s and triglycerides that is stored in the proventriculus
. This is used against predators as well as an energy rich food source for chicks and for the adults during their long flights. They also have a salt gland that is situated above the nasal passage and helps desalinate their bodies, due to the high amount of ocean water that they imbibe. It excretes a concentrated brine from the nostrils.
is black, with bright yellow upper and lower ridges, thatt shades to pink-orange at the tip. Its underwings are white with a lot of black on the leading edge and less on the trailing edge. Juveniles have a black bill and head and a darker nape. Its eye crescent is indistinct and its underwing is almost completely dark.
Grey-headed Albatrosses nest in colonies on several islands in the Southern Ocean, with large colonies on South Georgia in the South Atlantic, and smaller colonies on Islas Diego Ramírez, Kerguelen Islands
, Crozet Islands
, Marion Island, and Prince Edward Island
in the Indian Ocean
, Campbell Island
and Macquarie Island
south of New Zealand
, and Chile
. While breeding, they will forage for food within or south of the Antarctic Polar Frontal Zone. Birds that roost in the Marion Island area forage for food in the sub-tropical zone. Juveniles or non-breeding adults fly freely throughout all the southern oceans, north to 35°S.
. They feed predominantly on squid
, taking also some fish, crustacea, carrion
, cephalapods, and lamprey
s. Krill
is less important as a food source for this species, reflecting their more pelagic feeding range. They are capable of diving as deep as 7 m (23 ft) to chase prey, but do not do so frequently.
, which happens after 141 days. Chick will generally not return to the colony for 6–7 years after fledging, and will not breed for the first time until several years after that. If a pair of has managed to successfully raise a chick it will not breed in the following year, taking the year off. During this time spent away from the colony they can cover great distances, often circling the globe several times.
due to rapidly declining numbers. It has an occurrence range of 79000000 km² (30,502,070.5 sq mi) and a breeding range of 1800 km² (695 sq mi), with a population, estimated in 2004, of 250,000. Estimates have place 48,000 pairs at South Georgia Island, 6,200 on Marion Island, 3,000 pairs on Prince Edward Island
, 7,800 pairs on Campbell Island, 16,408 pairs in Chile
, 84 pairs on Macquarie Island
, 5,940 on Crozet Island, and 7,905 on Kerguelen Islands
Populations have been shrinking based on different studies. Bird Island numbers have been reduced 20% to 30% in the last 30 years. Marion Island registered 1.75% reduction per year until 1992 and now appears to be stable. Campbell Island has seen reduction of 79% to 87% since the 1940s. Overall, the trends looks like a 30-40% reduction over 90 years (3 generations). Illegal or unregulated fishing in the Indian Ocean
for the Patagonian toothfish
, Dissostichus eleginoides resulted in 10 - 20,000 dead Albatrosses, mainly this species, in 1997 and 1998. Longline fishing is responsible for other deaths. Finally, possible food loss due to rising ocean temperatures may be affecting this species.
To assist this species, studies are being undertaken at most of the islands. Also, Prince Edward Island
is a special nature preserve, and Campbell Island and Macquarie Island
are World Heritage Site
s.
Seabird
Seabirds are birds that have adapted to life within the marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent evolution, as the same environmental problems and feeding niches have resulted in similar adaptations...
from the albatross
Albatross
Albatrosses, of the biological family Diomedeidae, are large seabirds allied to the procellariids, storm-petrels and diving-petrels in the order Procellariiformes . They range widely in the Southern Ocean and the North Pacific...
family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
. It has a circumpolar
Antarctic Circumpolar Current
The Antarctic Circumpolar Current is an ocean current that flows from west to east around Antarctica. An alternative name for the ACC is the West Wind Drift. The ACC is the dominant circulation feature of the Southern Ocean and, at approximately 125 Sverdrups, the largest ocean current...
distribution, nesting on isolated islands in the Southern Ocean
Southern Ocean
The Southern Ocean comprises the southernmost waters of the World Ocean, generally taken to be south of 60°S latitude and encircling Antarctica. It is usually regarded as the fourth-largest of the five principal oceanic divisions...
and feeding at high latitudes, further south than any of the other mollymawk
Mollymawk
The mollymawks are a group of medium sized albatrosses that form the genus Thalassarche. The name has sometimes been used for the genus Phoebetria as well, but these are correctly called sooty albatrosses. They are restricted to the Southern Hemisphere, where they are the most common of the...
s. Its name derives from its ashy-grey head, throat and upper neck.
Taxonomy
Mollymawks are a type of albatross that belong to the Diomedeidae family and come from the ProcellariiformesProcellariiformes
Procellariiformes is an order of seabirds that comprises four families: the albatrosses, petrels and shearwaters, storm petrels, and diving petrels...
order, along with shearwater
Shearwater
Shearwaters are medium-sized long-winged seabirds. There are more than 30 species of shearwaters, a few larger ones in the genus Calonectris and many smaller species in the genus Puffinus...
s, fulmar
Fulmar
Fulmars are seabirds of the family Procellariidae. The family consists of two extant species and two that are extinct.-Taxonomy:As members of Procellaridae and then the order Procellariiformes, they share certain traits. First, they have nasal passages that attach to the upper bill called...
s, storm-petrel
Storm-petrel
Storm petrels are seabirds in the family Hydrobatidae, part of the order Procellariiformes. These smallest of seabirds feed on planktonic crustaceans and small fish picked from the surface, typically while hovering. The flight is fluttering and sometimes bat-like.Storm petrels have a cosmopolitan...
s, and diving-petrels. They share certain identifying features. First, they have nasal passages that attach to the upper bill called naricorns. Although the nostrils on the Albatross are on the sides of the bill. The bills of Procellariiformes are also unique in that they are split into between 7 and 9 horny plates. Finally, they produce a stomach oil made up of wax ester
Wax ester
An ester of a fatty acid and a long-chain alcohol. These oils have similar properties as triglycerides, but are indigestible. They are found in some fish such as orange roughy, oilfish, escolar, black oreo, smooth oreo and other deep water fish. They are also present in marine copepods. Wax...
s and triglycerides that is stored in the proventriculus
Proventriculus
The proventriculus is part of the digestive system of birds, invertebrates and insects.-Birds:The proventriculus is a standard part of avian anatomy...
. This is used against predators as well as an energy rich food source for chicks and for the adults during their long flights. They also have a salt gland that is situated above the nasal passage and helps desalinate their bodies, due to the high amount of ocean water that they imbibe. It excretes a concentrated brine from the nostrils.
Etymology
The meaning of the name chrysostoma is derived from two Greek words. Khrusos means gold and stoma means the mouth, in reference to its golden bill.Description
The Grey-headed Albatross averages 81 cm (31.9 in) in length and 2.2 m (7.2 ft) in wingspan. Weight can range from 2.8 to 4.4 kg (6.2 to 9.7 lb), with a mean mass of 3.65 kg (8 lb). It has a dark ashy-grey head, throat, and upper neck, and its upper wings, mantle, and tail, are almost black. It has a white rump, underparts, and a white crescent behind its eyes. Its billBeak
The beak, bill or rostrum is an external anatomical structure of birds which is used for eating and for grooming, manipulating objects, killing prey, fighting, probing for food, courtship and feeding young...
is black, with bright yellow upper and lower ridges, thatt shades to pink-orange at the tip. Its underwings are white with a lot of black on the leading edge and less on the trailing edge. Juveniles have a black bill and head and a darker nape. Its eye crescent is indistinct and its underwing is almost completely dark.
Range and habitat
| Location | Population | Date | Trend |
|---|---|---|---|
| South Georgia Island | 48,000 pair | 2006 | Declining |
| Marion Island | 6,200 pair | 2003 | Stable |
| Prince Edward Island Prince Edward Island Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population... |
3,000 pair | 2003 | |
| Campbell Island Campbell Island, New Zealand Campbell Island is a remote, subantarctic island of New Zealand and the main island of the Campbell Island group. It covers of the group's , and is surrounded by numerous stacks, rocks and islets like Dent Island, Folly Island , Isle de Jeanette Marie, and Jacquemart Island, the latter being the... |
7,800 pair | 2004 | Declining |
| Macquarie Island Macquarie Island Macquarie Island lies in the southwest corner of the Pacific Ocean, about half-way between New Zealand and Antarctica, at 54°30S, 158°57E. Politically, it has formed part of the Australian state of Tasmania since 1900 and became a Tasmanian State Reserve in 1978. In 1997 it became a world heritage... |
84 pair | 1998 | |
| Crozet Islands Crozet Islands The Crozet Islands are a sub-antarctic archipelago of small islands in the southern Indian Ocean. They form one of the five administrative districts of the French Southern and Antarctic Lands.-Geography:... |
5,940 pair | 1998 | |
| Kerguelen Islands Kerguelen Islands The Kerguelen Islands , also known as the Desolation Islands, are a group of islands in the southern Indian Ocean constituting the emerged part of the otherwise submerged Kerguelen Plateau. The islands, along with Adélie Land, the Crozet Islands and the Amsterdam and Saint Paul Islands are part of... |
7,905 pair | 1998 | |
| Islas Diego Ramirez | 16,408 pair | 2002 | |
| Total | 250,000 | 2004 | Decreasing |
Grey-headed Albatrosses nest in colonies on several islands in the Southern Ocean, with large colonies on South Georgia in the South Atlantic, and smaller colonies on Islas Diego Ramírez, Kerguelen Islands
Kerguelen Islands
The Kerguelen Islands , also known as the Desolation Islands, are a group of islands in the southern Indian Ocean constituting the emerged part of the otherwise submerged Kerguelen Plateau. The islands, along with Adélie Land, the Crozet Islands and the Amsterdam and Saint Paul Islands are part of...
, Crozet Islands
Crozet Islands
The Crozet Islands are a sub-antarctic archipelago of small islands in the southern Indian Ocean. They form one of the five administrative districts of the French Southern and Antarctic Lands.-Geography:...
, Marion Island, and Prince Edward Island
Prince Edward Island
Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population...
in the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
, Campbell Island
Campbell Island, New Zealand
Campbell Island is a remote, subantarctic island of New Zealand and the main island of the Campbell Island group. It covers of the group's , and is surrounded by numerous stacks, rocks and islets like Dent Island, Folly Island , Isle de Jeanette Marie, and Jacquemart Island, the latter being the...
and Macquarie Island
Macquarie Island
Macquarie Island lies in the southwest corner of the Pacific Ocean, about half-way between New Zealand and Antarctica, at 54°30S, 158°57E. Politically, it has formed part of the Australian state of Tasmania since 1900 and became a Tasmanian State Reserve in 1978. In 1997 it became a world heritage...
south of New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, and Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
. While breeding, they will forage for food within or south of the Antarctic Polar Frontal Zone. Birds that roost in the Marion Island area forage for food in the sub-tropical zone. Juveniles or non-breeding adults fly freely throughout all the southern oceans, north to 35°S.
Feeding
At sea the Grey-headed Albatross is highly pelagic, more so than other mollymawks, feeding in the open oceans rather than over the continental shelvesContinental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...
. They feed predominantly on squid
Squid
Squid are cephalopods of the order Teuthida, which comprises around 300 species. Like all other cephalopods, squid have a distinct head, bilateral symmetry, a mantle, and arms. Squid, like cuttlefish, have eight arms arranged in pairs and two, usually longer, tentacles...
, taking also some fish, crustacea, carrion
Carrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...
, cephalapods, and lamprey
Lamprey
Lampreys are a family of jawless fish, whose adults are characterized by a toothed, funnel-like sucking mouth. Translated from an admixture of Latin and Greek, lamprey means stone lickers...
s. Krill
Krill
Krill is the common name given to the order Euphausiacea of shrimp-like marine crustaceans. Also known as euphausiids, these small invertebrates are found in all oceans of the world...
is less important as a food source for this species, reflecting their more pelagic feeding range. They are capable of diving as deep as 7 m (23 ft) to chase prey, but do not do so frequently.
Reproduction
A single egg is laid in a large nest, typically built on steep slopes or cliffs with tussock grass, and incubated for 72 days. Studies at South Georgia's Bird Island have shown that the growing chick is fed 616 g (21.7 oz) of food every 1.2 days, with the chick increasing in weight to around 4900 g (172.8 oz). Chicks then tend to lose weight before fledgingFledge
Fledge is the stage in a young bird's life when the feathers and wing muscles are sufficiently developed for flight. It also describes the act of a chick's parents raising it to a fully grown state...
, which happens after 141 days. Chick will generally not return to the colony for 6–7 years after fledging, and will not breed for the first time until several years after that. If a pair of has managed to successfully raise a chick it will not breed in the following year, taking the year off. During this time spent away from the colony they can cover great distances, often circling the globe several times.
Conservation
The IUCN classifies this bird as vulnerableVulnerable species
On 30 January 2010, the IUCN Red List of Threatened Species identified 9694 Vulnerable species, subspecies and varieties, stocks and sub-populations.-References:...
due to rapidly declining numbers. It has an occurrence range of 79000000 km² (30,502,070.5 sq mi) and a breeding range of 1800 km² (695 sq mi), with a population, estimated in 2004, of 250,000. Estimates have place 48,000 pairs at South Georgia Island, 6,200 on Marion Island, 3,000 pairs on Prince Edward Island
Prince Edward Island
Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population...
, 7,800 pairs on Campbell Island, 16,408 pairs in Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
, 84 pairs on Macquarie Island
Macquarie Island
Macquarie Island lies in the southwest corner of the Pacific Ocean, about half-way between New Zealand and Antarctica, at 54°30S, 158°57E. Politically, it has formed part of the Australian state of Tasmania since 1900 and became a Tasmanian State Reserve in 1978. In 1997 it became a world heritage...
, 5,940 on Crozet Island, and 7,905 on Kerguelen Islands
Kerguelen Islands
The Kerguelen Islands , also known as the Desolation Islands, are a group of islands in the southern Indian Ocean constituting the emerged part of the otherwise submerged Kerguelen Plateau. The islands, along with Adélie Land, the Crozet Islands and the Amsterdam and Saint Paul Islands are part of...
Populations have been shrinking based on different studies. Bird Island numbers have been reduced 20% to 30% in the last 30 years. Marion Island registered 1.75% reduction per year until 1992 and now appears to be stable. Campbell Island has seen reduction of 79% to 87% since the 1940s. Overall, the trends looks like a 30-40% reduction over 90 years (3 generations). Illegal or unregulated fishing in the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
for the Patagonian toothfish
Patagonian toothfish
The Patagonian toothfish, Dissostichus eleginoides , is a fish found in the cold, temperate waters of the southern Atlantic, southern Pacific, Indian, and Southern Oceans on seamounts and continental shelves around most sub-Antarctic islands.A close relative, the Antarctic toothfish , is found...
, Dissostichus eleginoides resulted in 10 - 20,000 dead Albatrosses, mainly this species, in 1997 and 1998. Longline fishing is responsible for other deaths. Finally, possible food loss due to rising ocean temperatures may be affecting this species.
To assist this species, studies are being undertaken at most of the islands. Also, Prince Edward Island
Prince Edward Island
Prince Edward Island is a Canadian province consisting of an island of the same name, as well as other islands. The maritime province is the smallest in the nation in both land area and population...
is a special nature preserve, and Campbell Island and Macquarie Island
Macquarie Island
Macquarie Island lies in the southwest corner of the Pacific Ocean, about half-way between New Zealand and Antarctica, at 54°30S, 158°57E. Politically, it has formed part of the Australian state of Tasmania since 1900 and became a Tasmanian State Reserve in 1978. In 1997 it became a world heritage...
are World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...
s.