Atlantic Yellow-nosed Albatross
Encyclopedia
The Atlantic Yellow-nosed Albatross, Thalassarche chlororhynchos, is a large seabird
in the albatross
family
. This small mollymawk
was once considered conspecific with the Indian Yellow-nosed Albatross
and known as the Yellow-nosed Albatross. Some authorities still believe the species
to be the same, such as Jeff Clements and the SACC, which recognizes that a proposal is needed.
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 high saline solution from their nose.
patch, and its nape and hindneck are white. Its bill is black with a yellow culmenicorn and a pink tip. It has a blackish grey saddle, tail and upperwing, and its underparts are predominantly white. Its underwing and primaries show a narrow black margin. The juvenile is similar to the adult but with a white head and black bill. It can be differentiated from the Indian Yellow-nosed by its darker head. Relative to other mollymawks it can be distinguished by its smaller size (the wings being particularly narrow) and the thin black edging to the underwing, The Grey-headed Albatross
has a similar grey head but more extensive and less well defined black markings around the edge of the underwing. Salvin's Albatross
also has a grey head but has much broader wings, a pale bill and even narrower black borders to the underwing.
in scrub or amongst Blechnum
tree ferns. Like all mollymawks they build pedestal nests of mud, peat, feathers, and vegetation to lay their one egg
in. They do this in September or early October, and the chick fledge
s in late March to April. They breed annually.
(Inaccessible Island
, Middle Island
, Nightingale Island
, Stoltenhoff Island
) and Gough Island
. At sea they range across the south Atlantic from South America
to Africa
between 15° S and 45° S.
The IUCN list this species as Endangered, with an occurrence range of 16800000 km² (6,486,516.3 sq mi) and a breeding range of 80 km² (30.9 sq mi). A 2001 population estimate breaks down the population and shows some trends. Gough Island
has 5,300 breeding pairs, between 16,000 and 30,000 breeding pairs on Tristan da Cunha Island
, 4,500 on Nightingale Island
, between 100 and 200 pairs on Middle Island
, and 500 pairs on Stoltenhoff Island
, and 1,100 on Inaccessible Island
. This adds up to between 27,500 and 41,600 pairs per year for the total between 55,000 and 83,200 total adult birds. This population estimate was done in 1983, however and is outdated. Trends suggest a 50% decrease over 72 years.
The largest threat is from longline fishing, as harvesting of chicks and adults has been outlawed.
Efforts to help conserve this bird are underway, with counting of the birds on Gough Island
. Also, Gough Island
and Inaccessible Island
are nature preserves, and Gough Island
is a World Heritage Site
. The Tristan da Cunha
population is being remotely tracked and counted, and the South East Atlantic Fisheries Commission
has passed a resolution that all fishing vessels use a tori line and drop lines at night.
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...
in 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...
. This small 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...
was once considered conspecific with the Indian Yellow-nosed Albatross
Indian Yellow-nosed Albatross
The Indian Yellow-nosed Albatross, Thalassarche carteri, in the albatross family, and is the smallest of the mollymawks. In 2004, BirdLife International split this species from the Atlantic Yellow-nosed Albatross; however Clements has not split it yet, and the SACC has not either, but recognizes...
and known as the Yellow-nosed Albatross. Some authorities still believe the species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
to be the same, such as Jeff Clements and the SACC, which recognizes that a proposal is needed.
Taxonomy
Mollymawks are a type of Albatross that belong to 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 high saline solution from their nose.
Description
The Atlantic Yellow-nosed Albatross averages 81 cm (31.9 in) in length. It is a typical black and white mollymawk with a grey head and large eyeEye
Eyes are organs that detect light and convert it into electro-chemical impulses in neurons. The simplest photoreceptors in conscious vision connect light to movement...
patch, and its nape and hindneck are white. Its bill is black with a yellow culmenicorn and a pink tip. It has a blackish grey saddle, tail and upperwing, and its underparts are predominantly white. Its underwing and primaries show a narrow black margin. The juvenile is similar to the adult but with a white head and black bill. It can be differentiated from the Indian Yellow-nosed by its darker head. Relative to other mollymawks it can be distinguished by its smaller size (the wings being particularly narrow) and the thin black edging to the underwing, The Grey-headed Albatross
Grey-headed Albatross
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...
has a similar grey head but more extensive and less well defined black markings around the edge of the underwing. Salvin's Albatross
Salvin's Albatross
Salvin's Albatross, or Salvin's Mollymawk, Thalassarche salvini, is a large seabird that ranges across the Southern Ocean. A medium sized mollymawk in the albatross family, it was long considered to be a subspecies of the Shy Albatross...
also has a grey head but has much broader wings, a pale bill and even narrower black borders to the underwing.
Breeding
Like all albatrosses they are colonial, but unusually they will build their nestsBird nest
A bird nest is the spot in which a bird lays and incubates its eggs and raises its young. Although the term popularly refers to a specific structure made by the bird itself—such as the grassy cup nest of the American Robin or Eurasian Blackbird, or the elaborately woven hanging nest of the...
in scrub or amongst Blechnum
Blechnum
Blechnum is a genus of between 150–220 species of ferns in the family Blechnaceae, with a cosmopolitan distribution. By far the greatest species diversity is in tropical regions of the Southern Hemisphere, with only a few species reaching cool temperate latitudes in the Southern Hemisphere...
tree ferns. Like all mollymawks they build pedestal nests of mud, peat, feathers, and vegetation to lay their one egg
Egg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
in. They do this in September or early October, and the chick fledge
Fledge
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...
s in late March to April. They breed annually.
Range
Atlantic Yellow-nosed Albatrosses nest on islands in the mid-Atlantic, including Tristan da CunhaTristan da Cunha
Tristan da Cunha is a remote volcanic group of islands in the south Atlantic Ocean and the main island of that group. It is the most remote inhabited archipelago in the world, lying from the nearest land, South Africa, and from South America...
(Inaccessible Island
Inaccessible Island
Inaccessible Island is an extinct volcano, 14 km² in area, rising out of the South Atlantic Ocean 45 km southwest of Tristan da Cunha. Inaccessible Island is located at . It is part of the archipelago of Tristan da Cunha, which is part of the overseas territory of the United Kingdom,...
, Middle Island
Middle Island, Tristan da Cunha
Middle Island is a small, uninhabited island in the South Atlantic Ocean, part of the Nightingale Islands. They are governed as part of Tristan da Cunha, an archipelago that is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha.-External links:*...
, Nightingale Island
Nightingale Island
Nightingale Island is an island in the South Atlantic Ocean, 3 km² in area, part of the Tristan da Cunha group of islands. They are administered by the United Kingdom as part of the overseas territory of Saint Helena, Ascension and Tristan da Cunha....
, Stoltenhoff Island
Stoltenhoff Island
Stoltenhoff Island is a small uninhabited island in the South Atlantic Ocean, part of the Nightingale Islands. It is the smallest of the Nightingale Islands, and is to the north west of Nightingale Island itself...
) and Gough Island
Gough Island
Gough Island , also known historically as Gonçalo Álvares or Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha...
. At sea they range across the south Atlantic from South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
to Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
between 15° S and 45° S.
Conservation
| Location | Population | Date | Trend |
|---|---|---|---|
| Gough Island Gough Island Gough Island , also known historically as Gonçalo Álvares or Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha... |
5,300 pair | 2001 | Stable |
| Tristan da Cunha Island Tristan da Cunha Tristan da Cunha is a remote volcanic group of islands in the south Atlantic Ocean and the main island of that group. It is the most remote inhabited archipelago in the world, lying from the nearest land, South Africa, and from South America... |
16,000 - 30,000 pair | 1974 | Stable |
| Nightingale Island Nightingale Island Nightingale Island is an island in the South Atlantic Ocean, 3 km² in area, part of the Tristan da Cunha group of islands. They are administered by the United Kingdom as part of the overseas territory of Saint Helena, Ascension and Tristan da Cunha.... |
4,500 pair | 1974 | Declining |
| Middle Island Middle Island, Tristan da Cunha Middle Island is a small, uninhabited island in the South Atlantic Ocean, part of the Nightingale Islands. They are governed as part of Tristan da Cunha, an archipelago that is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha.-External links:*... |
100 - 200 pair | 1974 | |
| Stoltenhoff Island Stoltenhoff Island Stoltenhoff Island is a small uninhabited island in the South Atlantic Ocean, part of the Nightingale Islands. It is the smallest of the Nightingale Islands, and is to the north west of Nightingale Island itself... |
500 pair | 1974 | |
| Inaccessible Island Inaccessible Island Inaccessible Island is an extinct volcano, 14 km² in area, rising out of the South Atlantic Ocean 45 km southwest of Tristan da Cunha. Inaccessible Island is located at . It is part of the archipelago of Tristan da Cunha, which is part of the overseas territory of the United Kingdom,... |
1,100 pair | 1983 | Declining |
| Total | 55,000-83,200 | 2001 | Declining |
The IUCN list this species as Endangered, with an occurrence range of 16800000 km² (6,486,516.3 sq mi) and a breeding range of 80 km² (30.9 sq mi). A 2001 population estimate breaks down the population and shows some trends. Gough Island
Gough Island
Gough Island , also known historically as Gonçalo Álvares or Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha...
has 5,300 breeding pairs, between 16,000 and 30,000 breeding pairs on Tristan da Cunha Island
Tristan da Cunha
Tristan da Cunha is a remote volcanic group of islands in the south Atlantic Ocean and the main island of that group. It is the most remote inhabited archipelago in the world, lying from the nearest land, South Africa, and from South America...
, 4,500 on Nightingale Island
Nightingale Island
Nightingale Island is an island in the South Atlantic Ocean, 3 km² in area, part of the Tristan da Cunha group of islands. They are administered by the United Kingdom as part of the overseas territory of Saint Helena, Ascension and Tristan da Cunha....
, between 100 and 200 pairs on Middle Island
Middle Island, Tristan da Cunha
Middle Island is a small, uninhabited island in the South Atlantic Ocean, part of the Nightingale Islands. They are governed as part of Tristan da Cunha, an archipelago that is part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha.-External links:*...
, and 500 pairs on Stoltenhoff Island
Stoltenhoff Island
Stoltenhoff Island is a small uninhabited island in the South Atlantic Ocean, part of the Nightingale Islands. It is the smallest of the Nightingale Islands, and is to the north west of Nightingale Island itself...
, and 1,100 on Inaccessible Island
Inaccessible Island
Inaccessible Island is an extinct volcano, 14 km² in area, rising out of the South Atlantic Ocean 45 km southwest of Tristan da Cunha. Inaccessible Island is located at . It is part of the archipelago of Tristan da Cunha, which is part of the overseas territory of the United Kingdom,...
. This adds up to between 27,500 and 41,600 pairs per year for the total between 55,000 and 83,200 total adult birds. This population estimate was done in 1983, however and is outdated. Trends suggest a 50% decrease over 72 years.
The largest threat is from longline fishing, as harvesting of chicks and adults has been outlawed.
Efforts to help conserve this bird are underway, with counting of the birds on Gough Island
Gough Island
Gough Island , also known historically as Gonçalo Álvares or Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha...
. Also, Gough Island
Gough Island
Gough Island , also known historically as Gonçalo Álvares or Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha...
and Inaccessible Island
Inaccessible Island
Inaccessible Island is an extinct volcano, 14 km² in area, rising out of the South Atlantic Ocean 45 km southwest of Tristan da Cunha. Inaccessible Island is located at . It is part of the archipelago of Tristan da Cunha, which is part of the overseas territory of the United Kingdom,...
are nature preserves, and Gough Island
Gough Island
Gough Island , also known historically as Gonçalo Álvares or Diego Alvarez, is a volcanic island in the South Atlantic Ocean. It is a dependency of Tristan da Cunha and part of the British overseas territory of Saint Helena, Ascension and Tristan da Cunha...
is a 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...
. The Tristan da Cunha
Tristan da Cunha
Tristan da Cunha is a remote volcanic group of islands in the south Atlantic Ocean and the main island of that group. It is the most remote inhabited archipelago in the world, lying from the nearest land, South Africa, and from South America...
population is being remotely tracked and counted, and the South East Atlantic Fisheries Commission
South East Atlantic Fisheries Organisation
The South East Atlantic Fisheries Organisation is an organization that maintains controls over fishing and fishing related acts is the Southeastern Atlantic Ocean.-Introduction:...
has passed a resolution that all fishing vessels use a tori line and drop lines at night.