The Macquarie shag (''Leucocarbo purpurascens''), Macquarie Island shag or Macquarie Island cormorant, is a marine

cormorant Phalacrocoracidae is a family of approximately 40 species of aquatic birds commonly known as cormorants and shags. Several different classifications of the family have been proposed, but in 2021 the International Ornithologists' Union (IOU) ado ...

native to

Macquarie Island Macquarie Island is a subantarctic island in the south-western Pacific Ocean, about halfway between New Zealand and Antarctica. It has been governed as a part of Tasmania, Australia, since 1880. It became a Protected areas of Tasmania, Tasmania ...

in the

Southern Ocean The Southern Ocean, also known as the Antarctic Ocean, comprises the southernmost waters of the world ocean, generally taken to be south of 60th parallel south, 60° S latitude and encircling Antarctica. With a size of , it is the seco ...

, about halfway between

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

Taxonomy

The Macquarie shag is one of the

blue-eyed shag ''Leucocarbo'' is a genus of birds in the family Phalacrocoracidae. Several species within the genus are collectively known as blue-eyed shags. This is a group of closely related cormorant taxa. Many have a blue, purple or red ring around the eye ...

s, sometimes placed in the

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

''Leucocarbo'' or ''Notocarbo''. Others place it in the genus

Phalacrocorax ''Phalacrocorax'' is a genus of fish-eating birds in the cormorant family Phalacrocoracidae. Members of this genus are also known as the Old World cormorants. Taxonomy The genus ''Phalacrocorax'' was introduced by the French zoologist Mathurin ...

. It is now usually considered to be a full species.

Distribution and habitat

The Macquarie shag is restricted to

subantarctic The sub-Antarctic zone is a physiographic region in the Southern Hemisphere, located immediately north of the Antarctic region. This translates roughly to a latitude of between 46th parallel south, 46° and 60th parallel south, 60° south of t ...

Macquarie Island and the nearby

Bishop and Clerk Islets The Bishop and Clerk Islets are a group of islets, lying south of Macquarie Island in the southwestern Pacific Ocean. They are, with Macquarie Island, part of the Australian state of Tasmania. The group consists of Bishop Islet, 24 smaller ...

, part of the Macquarie group, 33 km to the south. Apart from breeding and roosting, its habitat is marine.

Description

The Macquarie shag has largely black upperparts and white underparts. The upper cheeks and ear-coverts are black; there are white bars on the wings, a black, recurved crest over the forehead, and pink feet.Marchant & Higgins (1991), p.867. A breeding adult has a pair of orange caruncles above the base of the bill in front of the eyes, orange-brown facial skin at the base of the lower mandible, as well as blue eye-rings. It is about 75 cm in length, with a

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the opposite wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingsp ...

of 110 cm and a weight of 2.5–3.5 kg.

Behaviour

Macquarie shags are gregarious, roosting in groups of from a few birds up to several hundred.Marchant & Higgins (1991), p.868.

Breeding

The birds are present all year round at Macquarie Island, where they breed annually in small to large

colonies A colony is a territory subject to a form of foreign rule, which rules the territory and its indigenous peoples separated from the foreign rulers, the colonizer, and their '' metropole'' (or "mother country"). This separated rule was often or ...

on bare rocky shores and stacks. Nest-building takes place from June. Nests are truncated cones, 20–30 cm in height, built of vegetation,

guano Guano (Spanish from ) is the accumulated excrement of seabirds or bats. Guano is a highly effective fertiliser due to the high content of nitrogen, phosphate, and potassium, all key nutrients essential for plant growth. Guano was also, to a le ...

and mud. The clutch of two or three eggs is laid between mid-September and January, mainly in late September and early November, with most eggs hatching by late December. Most chicks are independent of their parents by mid-February.

Feeding

The birds forage locally in shallow coastal waters,DEWHA website with the diet consisting primarily of

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

. Flocks may feed together.

Status and conservation

The Macquarie shag population was estimated in 2000 to comprise about 760 breeding pairs, including 100 pairs at the Bishop and Clerk Islets.Garnett & Crowley (2000). A later (October 2003) survey found 472 nesting pairs in eleven colonies on Macquarie Island itself, indicating a 30% decline.Schulz & Lynn (2003). The taxon is listed as Vulnerable under Australia's

Environment Protection and Biodiversity Conservation Act 1999 The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cult ...

, because the population is small, localised and subject to fluctuations in breeding success due to weather conditions and food availability. Other threats include predation of nestlings by

Subantarctic skua The brown skua (''Stercorarius antarcticus''), also known as the Antarctic skua, subantarctic skua, southern great skua, southern skua, or hākoakoa (Māori), is a large seabird that breeds in the subantarctic and Antarctic zones and moves furthe ...

s and

black rat The black rat (''Rattus rattus''), also known as the roof rat, ship rat, or house rat, is a common long-tailed rodent of the stereotypical rat genus ''Rattus'', in the subfamily Murinae. It likely originated in the Indian subcontinent, but is n ...

Notes

References

* DEWH
(Department of the Environment, Water, Heritage and the Arts) - ''Leucocarbo atriceps purpurascens'' - Imperial Shag (Macquarie Island).
Accessed 18 February 2009. * Garnett, Stephen T.; & Crowley, Gabriel M. (2000). ''The Action Plan for Australian Birds 2000''. Environment Australia: Canberra.

* Marchant, S.; & Higgins, P.J. (eds). (1991). ''Handbook of Australian, New Zealand and Antarctic Birds. Volume 1: Ratites to Ducks''. Oxford University Press: Melbourne. * Schulz, M.; & Lynn, J. (2003). ''Burrowing petrels on Macquarie Island, late March to early December 2003''. Report to Nature Conservation Branch, Department of Primary Industries, Water and Environment, Hobart, Tasmania. Department of Primary Industries, Water and Environment, Hobart, Tasmania. {{Taxonbar, from=Q1262501 Macquarie shag Fauna of Macquarie Island Birds of subantarctic islands Macquarie shag Birds of Australia Macquarie shag