The little black cormorant (''Phalacrocorax sulcirostris'') is a member of the

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 IOC adopted a consensus taxonomy of seven ge ...

family of

seabird Seabirds (also known as marine birds) are birds that are 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 envir ...

s. It is common in smaller rivers and lakes throughout most areas of Australia and northern

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 List of islands of New Zealand, smaller islands. It is the ...

, where it is known as the little black shag. It is around sixty centimetres long, and is all black with blue-green eyes.

Taxonomy

The little black cormorant was formally described in 1837 by the German born naturalist Johann Friedrich von Brandt. He placed it in the genus ''Carbo'' and coined the

binomial name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''Carbo sulcirostris''. The species is now placed 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 ...

'' that was introduced by the French zoologist

Mathurin Jacques Brisson Mathurin Jacques Brisson (; 30 April 1723 – 23 June 1806) was a French zoologist and natural philosopher. Brisson was born at Fontenay-le-Comte. The earlier part of his life was spent in the pursuit of natural history; his published wo ...

in 1760. The genus name ''Phalacrocorax'' is the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

word for a cormorant. The specific epithet ''sulcirostris'' combines the Latin ''sulcus'' meaning "furrow" with ''-rostris'' meaning "-billed". The species is

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

: no subspecies are recognised. The common name in New Zealand is the little black shag. A

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

study published in 2019 found that the little black cormorant was

sister A sister is a woman or a girl who shares one or more parents with another individual; a female sibling. The male counterpart is a brother. Although the term typically refers to a familial relationship, it is sometimes used endearingly to refer to ...

to the Indian cormorant. It is estimated that the two species split 2.5–3.2 million years ago during the late

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58 and legs and feet black. The iris of the adult is green and the juvenile brown. Immature birds have brown and black plumage.

Distribution and habitat

The little black cormorant ranges from the Malay Peninsula through Indonesia (but excluding Sumatra) and New Guinea (including the

D'Entrecasteaux Islands D'Entrecasteaux Islands () are situated near the eastern tip of New Guinea in the Solomon Sea in Milne Bay Province of Papua New Guinea. The group spans a distance of , has a total land area of approximately and is separated from the Papua New G ...

) and throughout Australia. It is found in New Zealand's North Island. It is a predominantly freshwater species, found in bodies of water inland and occasionally sheltered coastal areas. It is almost always encountered in or near water.

Behaviour

More gregarious than other cormorants, the little black cormorant can be found in large flocks. Groups sometimes fly in

V formation A V formation is the symmetric V-shaped flight formation of flights of geese, swans, ducks, and other migratory birds, improving their energy efficiency. Usually, large birds fly in this formation since smaller birds create more complex wind cu ...

Food and feeding

The little black cormorant feeds mainly on fish, and eats a higher proportion of fish than the frequently co-occurring

little pied cormorant The little pied cormorant, little shag or kawaupaka (''Microcarbo melanoleucos'') is a common Australasian waterbird, found around the coasts, islands, estuaries, and inland waters of Australia, New Guinea, New Zealand, Thailand, Myanmar, Singapo ...

, which eats more decapods. A field study at two storage lakes, Lake Cargelligo and Lake Brewster, in south-western New South Wales found that the introduced common carp made up over half of its food intake. Little black cormorants have been observed on the Wyong River, Central Coast, NSW, Australia. They feed in a pattern as a flock. Traveling in the same direction they take off from the water, flapping their wings against the water moving in the same direction for a few metres then land on the water and wait for others to land in front of them while they dive below the water to catch the scrambling fish groups. They are observed coming to the surface swallowing fish and then moving forward again. A group of cormorants can be in the hundreds and stay in a tight formation of 10 to 20 metres while moving forward.

Breeding

Breeding occurs once a year in spring or autumn in southern Australia, and before or after the monsoon in tropical regions. The nest is a small platform built of dried branches and sticks in the forks of trees that are standing in water. Nests are often located near other waterbirds such as other cormorants, herons, ibis, or spoonbills. Three to five (rarely six or seven) pale blue oval eggs measuring 48 x 32 mm are laid. The eggs are covered with a thin layer of lime, giving them a matte white coated appearance. They become increasingly stained with faeces, as does the nest, over the duration of the breeding season.

Various views and plumages

File:Little Black Cormorant Claisebrook Cove.jpg, Adult in

East Perth East or Orient is one of the four cardinal directions or points of the compass. It is the opposite direction from west and is the direction from which the Sun rises on the Earth. Etymology As in other languages, the word is formed from the fac ...

File:Little Black Cormorant RWD1.jpg, Manly (near Sydney) File:Little Black Cormorants, Shoalhaven River.jpg,

Shoalhaven River The Shoalhaven River is a perennial river that rises from the Southern Tablelands and flows into an open mature wave dominated barrier estuary near Nowra on the South Coast of New South Wales, Australia. Location and features The Shoalh ...

Phalacrocorax sulcirostris - Gould's Lagoon.jpg, Pair in flight