White-capped Albatross
Encyclopedia
The White-capped Albatross, Thalassarche steadi, is a mollymawk
that breeds on the islands off of New Zealand
. Not all experts agree that this form should be recognized as a separate species to the Shy Albatross, Thalassarche cauta. It is a medium sized black, slate grey, and white albatross and is the largest of the mollymawks.
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.
The White-capped Albatross is part of a greater complex of Albatrosses consisting of the Shy Albatross
, Thasassarche cauta, Salvin's Albatross
, Thalassarche salvini, Chatham Albatross
, Thalassarche eremita. In 1998, Robertson and Nunn recommended a four way split, some experts agreed. BirdLife International agreed in 2007, ACAP
agreed in 2006, and Brooke agreed in 2004. The SACC
agreed to a three-way split, leaving steadi, the White-capped Albatross grouped with the Shy Albatross
. James Clements
has yet to agree on any of these splits. Finally, following Brooke, this species was shifted from Diomedea to Thalassarche, which was generally agreed upon by most experts.
They are endemic
to the islands off the coast of New Zealand
, with a population of 75,000 breeding pairs, estimated in 2007, and 350,000 to 375,000 total birds. Disappointment Island
has 72,000 pairs, Auckland Island
has 3,000 pairs, Adams Island
(Auckland Islands
) has 100 pairs, and Bollons Island (Antipodes Islands
) has 100 pairs.
Juvenile and non-breeding birds are believed to forage in the southwestern Atlantic and a recent DNA test of a South Georgia bird confirmed it. Also, using different techniques, scientists have proven that they forage off the coast of southwestern Africa
.Robertson, C. J. R., et al. (2003) Juveniles are also believe to go as far as the south Atlantic and the southwestern Indian Ocean
.
s, tunicate
s, and crustacea.
, with an occurrence range of 77700000 km² (30,000,137.7 sq mi) and a breeding range of 22 km² (8.5 sq mi). The largest threat for this bird is longline and trawl fisheries. Net monitor cables were responsible for large amounts of deaths; however, they were phased out in 1992. Commercial exploitation of the squid in Bass Strait
may present a threat by reducing the food supply Also, pigs on Auckland Island
reduced nesting from 1972–1982, and feral cats also take small number of chicks.
Since 2006, Auckland Island
birds have started to have been tracked, and this will be ongoing.
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...
that breeds on the islands off 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...
. Not all experts agree that this form should be recognized as a separate species to the Shy Albatross, Thalassarche cauta. It is a medium sized black, slate grey, and white albatross and is the largest of the mollymawks.
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.
The White-capped Albatross is part of a greater complex of Albatrosses consisting of the Shy Albatross
Shy Albatross
The Shy Albatross or Shy Mollymawk, Thalassarche cauta, is a medium sized albatross that breeds off Australia and New Zealand's sub-Antarctic islands and ranges extensively across the Southern Ocean...
, Thasassarche cauta, 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...
, Thalassarche salvini, Chatham Albatross
Chatham Albatross
The Chatham Albatross, Chatham Mollymawk, or Chatham Islands Mollymawk, Thalassarche eremita, is a medium-sized black-and-white albatross which breeds only on The Pyramid, a large rock stack in the Chatham Islands, New Zealand. It is sometimes treated as a subspecies of the Shy Albatross...
, Thalassarche eremita. In 1998, Robertson and Nunn recommended a four way split, some experts agreed. BirdLife International agreed in 2007, ACAP
Agreement on the Conservation of Albatrosses and Petrels
The Agreement on the Conservation of Albatrosses and Petrels is a legally binding international treaty signed in 2001.It was created in order to halt the drastic decline of seabird populations in the Southern Hemisphere, particularly albatrosses and procellariids...
agreed in 2006, and Brooke agreed in 2004. The SACC
American Ornithologists' Union
The American Ornithologists' Union is an ornithological organization in the USA. Unlike the National Audubon Society, its members are primarily professional ornithologists rather than amateur birders...
agreed to a three-way split, leaving steadi, the White-capped Albatross grouped with the Shy Albatross
Shy Albatross
The Shy Albatross or Shy Mollymawk, Thalassarche cauta, is a medium sized albatross that breeds off Australia and New Zealand's sub-Antarctic islands and ranges extensively across the Southern Ocean...
. James Clements
James Clements
Dr. James Franklin Clements was an ornithologist, author and very successful businessman. He was born in New York....
has yet to agree on any of these splits. Finally, following Brooke, this species was shifted from Diomedea to Thalassarche, which was generally agreed upon by most experts.
Description
The White-capped Albatross averages 90 to 99 cm (35.4 to 39 in) in length, with a wingspan of 220 to 256 cm (86.6 to 100.8 in). It has a bold white cap that contrasts with a pale silver grey face and a darker brow. Some adults have white back with brown tipped feathers. They have a dark grey mantle and a black tail. Most of the rest of the body is white. Its bill is pale grey to blue with a yellow tip. Juveniles have a grey bill with a dark tip, and their head is darker, with grey to the collar.Range and habitat
| Location | Population | Date | Trend |
|---|---|---|---|
| Disappointment Island Disappointment Island Disappointment Island is one of seven uninhabited islands of the archipelago Auckland Islands. It is from the north-west end of Auckland Island and south of New Zealand. It is home to the White-capped Albatross. About 65,000 pairs - nearly the entire world population - nest on Disappointment... |
72,000 pair | 1993 | |
| Auckland Island Auckland Island Auckland Island is the main island of the Auckland Islands, an uninhabited archipelago in the south Pacific Ocean belonging to New Zealand. It is inscribed in the together with the other subantarctic New Zealand islands in the region as follows: 877-004 Auckland Isls, New Zealand S50.29 E165.52... |
3,000 pair | ||
| Antipodes Island | 50—100 pair | 1994 | |
| Adams Island Adams Island, New Zealand Adams Island is part of Auckland Islands archipelago. The southern end of Auckland Island broadens to a width of where a narrow channel, known as Carnley Harbour or the Adams Straits, separates it from the roughly triangular Adams Island , which is even more mountainous, reaching a height of at... |
100 pair | ||
| Total | 150,000 | 1993 | Stable |
They are endemic
Endemism in birds
An endemic bird area is a region of the world that contains two or more restricted-range species, while a "secondary area" contains one or more restricted-range species. Both terms were devised by Birdlife International....
to the islands off the coast 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...
, with a population of 75,000 breeding pairs, estimated in 2007, and 350,000 to 375,000 total birds. Disappointment Island
Disappointment Island
Disappointment Island is one of seven uninhabited islands of the archipelago Auckland Islands. It is from the north-west end of Auckland Island and south of New Zealand. It is home to the White-capped Albatross. About 65,000 pairs - nearly the entire world population - nest on Disappointment...
has 72,000 pairs, Auckland Island
Auckland Island
Auckland Island is the main island of the Auckland Islands, an uninhabited archipelago in the south Pacific Ocean belonging to New Zealand. It is inscribed in the together with the other subantarctic New Zealand islands in the region as follows: 877-004 Auckland Isls, New Zealand S50.29 E165.52...
has 3,000 pairs, Adams Island
Adams Island, New Zealand
Adams Island is part of Auckland Islands archipelago. The southern end of Auckland Island broadens to a width of where a narrow channel, known as Carnley Harbour or the Adams Straits, separates it from the roughly triangular Adams Island , which is even more mountainous, reaching a height of at...
(Auckland Islands
Auckland Islands
The Auckland Islands are an archipelago of the New Zealand Sub-Antarctic Islands and include Auckland Island, Adams Island, Enderby Island, Disappointment Island, Ewing Island, Rose Island, Dundas Island and Green Island, with a combined area of...
) has 100 pairs, and Bollons Island (Antipodes Islands
Antipodes Islands
The Antipodes Islands are inhospitable volcanic islands to the south of—and territorially part of—New Zealand...
) has 100 pairs.
Juvenile and non-breeding birds are believed to forage in the southwestern Atlantic and a recent DNA test of a South Georgia bird confirmed it. Also, using different techniques, scientists have proven that they forage off the coast of southwestern 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...
.Robertson, C. J. R., et al. (2003) Juveniles are also believe to go as far as the south Atlantic and the southwestern 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...
.
Feeding
They are a surface feeder, but may utilize shallow dives for their food which is fish, cephalopodCephalopod
A cephalopod is any member of the molluscan class Cephalopoda . These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot...
s, tunicate
Tunicate
Tunicates, also known as urochordates, are members of the subphylum Tunicata, previously known as Urochordata, a group of underwater saclike filter feeders with incurrent and excurrent siphons that is classified within the phylum Chordata. While most tunicates live on the ocean floor, others such...
s, and crustacea.
Conservation
The IUCN classifies this species as Near ThreatenedNear Threatened
Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status...
, with an occurrence range of 77700000 km² (30,000,137.7 sq mi) and a breeding range of 22 km² (8.5 sq mi). The largest threat for this bird is longline and trawl fisheries. Net monitor cables were responsible for large amounts of deaths; however, they were phased out in 1992. Commercial exploitation of the squid in Bass Strait
Bass Strait
Bass Strait is a sea strait separating Tasmania from the south of the Australian mainland, specifically the state of Victoria.-Extent:The International Hydrographic Organization defines the limits of the Bass Strait as follows:...
may present a threat by reducing the food supply Also, pigs on Auckland Island
Auckland Island
Auckland Island is the main island of the Auckland Islands, an uninhabited archipelago in the south Pacific Ocean belonging to New Zealand. It is inscribed in the together with the other subantarctic New Zealand islands in the region as follows: 877-004 Auckland Isls, New Zealand S50.29 E165.52...
reduced nesting from 1972–1982, and feral cats also take small number of chicks.
Since 2006, Auckland Island
Auckland Island
Auckland Island is the main island of the Auckland Islands, an uninhabited archipelago in the south Pacific Ocean belonging to New Zealand. It is inscribed in the together with the other subantarctic New Zealand islands in the region as follows: 877-004 Auckland Isls, New Zealand S50.29 E165.52...
birds have started to have been tracked, and this will be ongoing.