Light-mantled Albatross
Encyclopedia
The Light-mantled Albatross, Phoebetria palpebrata, also known as the Grey-mantled Albatross or the Light-mantled Sooty Albatross, is a small albatross
in the genus
Phoebetria, which it shares with the Sooty Albatross
. The Light-mantled Albatross was first described as Phoebetria palpebrata by Johann Reinhold Forster
, in 1785, based on a specimen from south of the Cape of Good Hope
.
called naricorns, though with albatrosses these are on the sides of the upper mandible rather than the top. They also have a salt gland above the nasal passage which excretes a concentrated saline solution to maintain osmotic balance
, due to the amount of seawater imbibed. The bills of the Procellariiformes are unique in that they are covered with from seven to nine horny plates. These birds produce a stomach oil made up of wax ester
s and triglycerides that is stored in the proventriculus
. This is used to deter predators as well as an energy rich food source for chicks and for the adults during their long flights.
. The eyes are partly encircled with thin post-orbital crescents of very short grey feathers. The bill
is black with a blue sulcus and a greyish-yellow line along the lower mandible
, and is about 105 mm (4.1 in). Measurements show that males and females are similar in size, with average length of 79 to 89 cm (31.1 to 35 in), wing-span of 183 to 218 cm (72 to 85.8 in), and weight of 2.5 to 3.7 kg (5.5 to 8.2 lb).
pelagic distribution in the Southern Ocean
. It ranges in latitude from the pack-ice
around Antarctica, with the southernmost record from 78°S in the Ross Sea
, to about 35°S, with occasional records from further north along the Humboldt Current
. It breeds on several subantarctic islands including the Prince Edward Island
, Marion Island, Crozet Islands
, Amsterdam Island, St. Paul Island
, Kerguelen Islands
, Heard Island, Macquarie Island
, Campbell Island
, Auckland Islands
, Antipodes Islands
and South Georgia and at least on one island in the maritime Antarctic at 62°S on King George Island. Except when breeding, its habitat is entirely marine
, and it will forage from the edges of the Antarctic pack-ice to about 40° S. When foraging during the breeding season, the birds will remain closer to their nest sites.
is built on a vegetated cliff ledge, or a steep slope, sheltered from the prevailing westerly winds. Structurally it is a low mound of peat and mud, 15 to 30 cm (5.9 to 11.8 in) high and 45 to 55 cm (17.7 to 21.7 in) wide at the base, with a cupped hollow at the top. It incorporates some plant material and with a grass lining. Around October or November, a single egg
is laid, which is not replaced if lost. Both sexes incubate
alternately in shifts that vary from a day or two up to nearly a month in length. The incubation period is 65–72 days. After hatching in December or January, which takes 3 to 5 days, the chicks are brooded in shifts for about 20 days, following which they are left alone in the nests while the adults forage, returning to feed the chicks by regurgitation
every 2–3 days. The entire nestling period from hatching to fledging
, which occurs in May or June, lasts 140–170 days. Pairs form committed pair-bonds
which may last for decades, being renewed through complex courtship displays
at the breeding site. On average, birds begin breeding when they reach 8 to 15 years old, after which they breed biennially, fledging a chick every five years or so. They are capable of breeding until at least 32 years old and living to 40 or longer.
and krill
, though other crustacean
s and fish
are taken as well as seal
, penguin
and petrel
carrion
. They sometimes feed in association with pilot whales and Southern Right Whale Dolphin
s, and occasionally follow ships. Food is usually taken on or close to the surface of the ocean, within a depth of 5 m (16.4 ft), though there is a record of a 12 m (39.4 ft) dive.
, with an occurrence range of 44300000 km² (17,104,325.6 sq mi).
Potential predators on some breeding islands are giant petrel
s, feral cat
s and rodents. At sea they are threatened by bycatch
in the longline fishery and through starvation by eating plastic
marine debris
.
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...
in the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Phoebetria, which it shares with the Sooty Albatross
Sooty Albatross
The Sooty Albatross, Dark-mantled Sooty Albatross or Dark-mantled Albatross, Phoebetria fusca, is a species of bird in the albatross family...
. The Light-mantled Albatross was first described as Phoebetria palpebrata by Johann Reinhold Forster
Johann Reinhold Forster
Johann Reinhold Forster was a German Lutheran pastor and naturalist of partial Scottish descent who made contributions to the early ornithology of Europe and North America...
, in 1785, based on a specimen from south of the Cape of Good Hope
Cape of Good Hope
The Cape of Good Hope is a rocky headland on the Atlantic coast of the Cape Peninsula, South Africa.There is a misconception that the Cape of Good Hope is the southern tip of Africa, because it was once believed to be the dividing point between the Atlantic and Indian Oceans. In fact, the...
.
Physiology
Light-mantled Albatrosses share some identifying features with other Procellariiformes. They have nasal tubes on the upper 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...
called naricorns, though with albatrosses these are on the sides of the upper mandible rather than the top. They also have a salt gland above the nasal passage which excretes a concentrated saline solution to maintain osmotic balance
Osmoregulation
Osmoregulation is the active regulation of the osmotic pressure of an organism's fluids to maintain the homeostasis of the organism's water content; that is it keeps the organism's fluids from becoming too diluted or too concentrated. Osmotic pressure is a measure of the tendency of water to move...
, due to the amount of seawater imbibed. The bills of the Procellariiformes are unique in that they are covered with from seven to nine horny plates. These birds 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 to deter predators as well as an energy rich food source for chicks and for the adults during their long flights.
Description
The Light-mantled Albatross is largely sooty-brown or blackish in colour, darker on the head, with paler upperparts from the nape to the upper tail-coverts which are grey to light grey, palest on the mantle and back. The plumage has been described as being similar in appearance to the colouring of a Siamese catSiamese (cat)
The Siamese is one of the first distinctly recognized breeds of Oriental cat. The origins of the breed are unknown, but it is believed to be from Thailand. In Thailand, where they are one of several native breeds, they are called Wichian Mat...
. The eyes are partly encircled with thin post-orbital crescents of very short grey feathers. The bill
Beak
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 a blue sulcus and a greyish-yellow line along the lower mandible
Mandible
The mandible pronunciation or inferior maxillary bone forms the lower jaw and holds the lower teeth in place...
, and is about 105 mm (4.1 in). Measurements show that males and females are similar in size, with average length of 79 to 89 cm (31.1 to 35 in), wing-span of 183 to 218 cm (72 to 85.8 in), and weight of 2.5 to 3.7 kg (5.5 to 8.2 lb).
Distribution and habitat
The Light-mantled Albatross has a circumpolarAntarctic Circle
The Antarctic Circle is one of the five major circles of latitude that mark maps of the Earth. For 2011, it is the parallel of latitude that runs south of the Equator.-Description:...
pelagic distribution 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...
. It ranges in latitude from the pack-ice
Drift ice
Drift ice is ice that floats on the surface of the water in cold regions, as opposed to fast ice, which is attached to a shore. Usually drift ice is carried along by winds and sea currents, hence its name, "drift ice"....
around Antarctica, with the southernmost record from 78°S in the Ross Sea
Ross Sea
The Ross Sea is a deep bay of the Southern Ocean in Antarctica between Victoria Land and Marie Byrd Land.-Description:The Ross Sea was discovered by James Ross in 1841. In the west of the Ross Sea is Ross Island with the Mt. Erebus volcano, in the east Roosevelt Island. The southern part is covered...
, to about 35°S, with occasional records from further north along the Humboldt Current
Humboldt Current
The Humboldt Current , also known as the Peru Current, is a cold, low-salinity ocean current that flows north-westward along the west coast of South America from the southern tip of Chile to northern Peru. It is an eastern boundary current flowing in the direction of the equator, and can extend...
. It breeds on several subantarctic islands including the Prince Edward Island
Prince Edward Islands
The Prince Edward Islands are two small islands in the sub-antarctic Indian Ocean that are part of South Africa. The islands, named Marion Island and Prince Edward Island, are located at ....
, Marion Island, 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:...
, Amsterdam Island, St. Paul Island
Île Saint-Paul
Île Saint-Paul is an island forming part of the French Southern and Antarctic Lands in the Indian Ocean, with an area of . It is located about southwest of the larger Île Amsterdam, and south of Réunion...
, 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...
, Heard Island, 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...
, 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...
, 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...
, Antipodes Islands
Antipodes Islands
The Antipodes Islands are inhospitable volcanic islands to the south of—and territorially part of—New Zealand...
and South Georgia and at least on one island in the maritime Antarctic at 62°S on King George Island. Except when breeding, its habitat is entirely marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
, and it will forage from the edges of the Antarctic pack-ice to about 40° S. When foraging during the breeding season, the birds will remain closer to their nest sites.
Behaviour
They have a loud shrill voice that is trumpet-like, and when threatened will snap their bills or utilize a throaty 'gaaaa'. When courting will utilize aerial displays and formation flying. They will also use mutual calling with deviations in tone brought occurring by head positioning, and finally, they do use their tail in displays more than other albatrosses.Reproduction
The species breeds in loose colonies or small groups, and sometimes is a solitary breeder. The nestBird 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...
is built on a vegetated cliff ledge, or a steep slope, sheltered from the prevailing westerly winds. Structurally it is a low mound of peat and mud, 15 to 30 cm (5.9 to 11.8 in) high and 45 to 55 cm (17.7 to 21.7 in) wide at the base, with a cupped hollow at the top. It incorporates some plant material and with a grass lining. Around October or November, a single 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...
is laid, which is not replaced if lost. Both sexes incubate
Avian incubation
Incubation refers to the process by which certain oviparous animals hatch their eggs, and to the development of the embryo within the egg. The most vital factor of incubation is the constant temperature required for its development over a specific period. Especially in domestic fowl, the act of...
alternately in shifts that vary from a day or two up to nearly a month in length. The incubation period is 65–72 days. After hatching in December or January, which takes 3 to 5 days, the chicks are brooded in shifts for about 20 days, following which they are left alone in the nests while the adults forage, returning to feed the chicks by regurgitation
Regurgitation (digestion)
Regurgitation is the expulsion of material from the mouth, pharynx, or esophagus, usually characterized by the presence of undigested food or blood.Regurgitation is used by a number of species to feed their young...
every 2–3 days. The entire nestling period from hatching to fledging
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...
, which occurs in May or June, lasts 140–170 days. Pairs form committed pair-bonds
Pair bond
In biology, a pair bond is the strong affinity that develops in some species between the males and females in a pair, potentially leading to breeding. Pair-bonding is a term coined in the 1940s that is frequently used in sociobiology and evolutionary psychology circles...
which may last for decades, being renewed through complex courtship displays
Mating
In biology, mating is the pairing of opposite-sex or hermaphroditic organisms for copulation. In social animals, it also includes the raising of their offspring. Copulation is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization...
at the breeding site. On average, birds begin breeding when they reach 8 to 15 years old, after which they breed biennially, fledging a chick every five years or so. They are capable of breeding until at least 32 years old and living to 40 or longer.
| Breeding Location | Breeding Pairs | Trend |
|---|---|---|
| Possession Island Possession Island Possession Island may refer to:* Possession Island, Namibia, on the Skeleton Coast of Africa* Possession Island , in the Torres Strait, Australia* Possession Island, Antarctica, in the Possession Islands group... |
996 | -13% over 15 years |
| Rest 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:... |
1,404 | Unknown |
| South Georgia | 5,000 to 7,500 | Unknown |
| 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... |
3,000 to 5,000 | Unknown |
| 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... |
5,000 | Unknown |
| 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... |
2,000 | Unknown |
| 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... |
1,600 | Unknown |
| Antipodes Island | 170 | Unknown |
| Heard Island | 200 to 500 | Unknown |
| Marion Island | 179 | Stable |
| Prince Edward Island Prince Edward Islands The Prince Edward Islands are two small islands in the sub-antarctic Indian Ocean that are part of South Africa. The islands, named Marion Island and Prince Edward Island, are located at .... |
150 | Unknown |
| King George Island | 5 | Unknown |
| Total | 58,000 | -20% to -29% over 100 years |
Feeding
The principal diet of Light-mantled Albatrosses consists of squidCephalopod
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...
and 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...
, though other crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s and fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
are taken as well as seal
Pinniped
Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...
, penguin
Penguin
Penguins are a group of aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica. Highly adapted for life in the water, penguins have countershaded dark and white plumage, and their wings have become flippers...
and petrel
Petrel
Petrels are tube-nosed seabirds in the bird order Procellariiformes. The common name does not indicate relationship beyond that point, as "petrels" occur in three of the four families within that group...
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...
. They sometimes feed in association with pilot whales and Southern Right Whale Dolphin
Southern Right Whale Dolphin
The southern right whale dolphin, Lissodelphis peronii, is a small and slender species of mammal found in cool waters of the southern hemisphere...
s, and occasionally follow ships. Food is usually taken on or close to the surface of the ocean, within a depth of 5 m (16.4 ft), though there is a record of a 12 m (39.4 ft) dive.
Conservation
The Light-mantled Albatross population is estimated at about 58,000, from a 1998 estimate, and is declining. Threats and population status are poorly quantified and the species is classified 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 44300000 km² (17,104,325.6 sq mi).
Potential predators on some breeding islands are giant petrel
Giant petrel
Giant petrels is a genus, Macronectes, from the family Procellariidae and consist of two species. They are the largest birds from this family...
s, feral cat
Feral cat
A feral cat is a descendant of a domesticated cat that has returned to the wild. It is distinguished from a stray cat, which is a pet cat that has been lost or abandoned, while feral cats are born in the wild; the offspring of a stray cat can be considered feral if born in the wild.In many parts of...
s and rodents. At sea they are threatened by bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
in the longline fishery and through starvation by eating plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...
marine debris
Marine debris
Marine debris, also known as marine litter, is human created waste that has deliberately or accidentally become afloat in a lake, sea, ocean or waterway. Oceanic debris tends to accumulate at the centre of gyres and on coastlines, frequently washing aground, when it is known as beach litter or...
.