''Girella cyanea'', also known as the blue drummer or Australian bluefish, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of sea chub native to inshore waters, around depth, from

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

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 smaller islands. It is the sixth-largest island count ...

and the Kermadec Islands. Sightings were first recorded in 1881 but the species made its debut in scientific publications in 1919 in Theodore Roughly's'' Fishes of Australia and Their Technology''.

Description

''Girella cyanea'' can be recognized by its blue coloration and yellow spots, with its blueish color becoming a greyish-green in post mortem. The adults of this species are they can attain a length of 76cm and their bright flank spots are distinctive. When they are younger they are greeny-grey in colour and the spots are paler yellow. These fish have a small beak-like mouth and they have large scales.

Sea chubs The sea chubs, also known as rudderfish and pilot fish and in Hawaiian as ''enenue'' or ''nenue'', are a family, Kyphosidae, of fishes in the order Perciformes native to the Atlantic, Indian and Pacific Oceans usually close to shore in marine w ...

are easily recognized by distinct morphological characteristics such as their ovate-shaped bodies, small mouths, and weakly-forked strong caudal fin. A key characteristic also being a spinous dorsal fin with low spines followed by a higher evenly curved or falcate soft dorsal fin.

Distribution & habitat

''Girella cyanea'' are commonly found in the south-west

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

; occurring along the east coast of

from

Flinders Reef Flinders Reef is a small isolated reef near Moreton Island, north-east of Cape Moreton in South East Queensland, Australia. It has the highest number of coral species of any subtropical reef system along Australia's east coast and is the neares ...

off Cape Moreton in Queensland to Eden in southern

New South Wales ) , nickname = , image_map = New South Wales in Australia.svg , map_caption = Location of New South Wales in AustraliaCoordinates: , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , es ...

. The species can also be found at Elizabeth and Middleton Reefs, Lord Howe and Norfolk Islands, and New Zealand's North and Kermadec Islands. Bluefish are ocean dwellers and do not generally enter rivers or

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environment ...

. Juveniles are known to live in tidal pools until they reach adulthood and form schools over reef areas. Adults can typically be found in coastal and offshore rocky reef areas in New South Wales at depths ranging from .

Ecology

''Girella cyanea'' are omnivorous; they are known to eat crustaceans, smaller fishes, mollusks; along with calcareous seaweeds, brittle stars, cunjevoi, and marine worms. They are known to feed at dawn and dusk when they are most active. An

ontogenetic Ontogeny (also ontogenesis) is the origination and development of an organism (both physical and psychological, e.g., moral development), usually from the time of fertilization of the egg to adult. The term can also be used to refer to the st ...

diet was found in fish less than standard length. Those found in intertidal habitat having a mainly carnivorous diet and a digestive system without developed pyloric caeca. In contrast, pyloric caeca were well-developed in fish larger than and their diets possessed increased ingestion of algae.

Reproduction

''Girella cyanea'' is a fast-growing and long-lived fish, with the oldest observed specimen being 41 years old. It is believed they transition into sexual maturity between 2 and 5 years of age or when they reach in length.

Conservation efforts

A fishing closure was placed across the state of

in 2006 due to the lack of sightings at the coast; despite the lack of official endangered species status. However, recreational fishing is still permitted on Lord Howe Island. A bag limit of 5 fish per person per day is enforced in protection zones across the Marine Park. Taking or possessing bluefish from New South Wales waters, other than designated areas, is an offense that carries a multitude of penalties. Penalties for taking bluefish in contravention of the fishing closure can include fines of up to $110,000 for corporations while individuals can face fines of up to $22,000 along with up to 6 months in prison, or both. Penalties for possessing a Blue Drummer despite the fishing closure can include fines of up to $55,000 for corporations, while individuals can face fines of up to $11,000 and up to 3 months in prison, or both.

References

* * Tony Ayling & Geoffrey Cox, ''Collins Guide to the Sea Fishes of New Zealand'', (William Collins Publishers Ltd, Auckland, New Zealand 1982) {{Taxonbar, from=Q3228440 cyanea Taxa named by William John Macleay Fish described in 1881 Fish of Lord Howe Island