Blue groper
Encyclopedia
A blue groper is a member of two similar species of fish found in the coastal waters of southern Australia
, distinguished by the bright blue colouring of the adult males. The Eastern blue groper (Achoerodus viridis) is found from Hervey Bay in southern Queensland
to Wilsons Promontory
in Victoria
. The range of the Western blue groper (Achoerodus gouldii) stretches from the Houtman Abrolhos
in Western Australia
to west of Melbourne
. Despite their name, they are not grouper
s, but wrasse
s (family Labridae).
The thick bodied blue gropers have peg teeth, heavy scales, a large tail and thick lips. Juveniles are brown to green brown. Adult females are brown to reddish-brown. Each scale may have a darker red spot. The adult males have the bright blue colouring that give the fish their name. The blue can range from deep navy
to cobalt
blue, and there may also be darker or yellow-orange spots or lines around the eyes.
All blue gropers begin their life as females. As they mature, they go through an initial phase, in which they may be male or female, before developing their adult colouring and reaching the terminal phase. Eastern blue gropers have been known to grow to 1.2 metres (4 ft) in length and weights of 22 kilograms, although fish over 15 kg are rare. The western species is larger, reaching 1.6 m and 40 kg.
The fish live in a variety of coastal waters, especially exposed reef
s. The Western blue groper lives in water 5–65 m deep, and the eastern species from the shallows up to 40 m deep. They feed on invertebrates such as sea urchin
s, crab
s and mussel
s. For the eastern species, spawning occurs from July until October, in estuarine
seagrass
beds, where the juveniles are usually found.
In 1998, the Eastern blue groper was made the state fish emblem of New South Wales
.
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, distinguished by the bright blue colouring of the adult males. The Eastern blue groper (Achoerodus viridis) is found from Hervey Bay in southern Queensland
Queensland
Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
to Wilsons Promontory
Wilsons Promontory
Wilsons Promontory is a peninsula that forms the southernmost part of the Australian mainland and is located at . South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia...
in Victoria
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
. The range of the Western blue groper (Achoerodus gouldii) stretches from the Houtman Abrolhos
Houtman Abrolhos
The Houtman Abrolhos is a chain of 122 islands, and associated coral reefs, in the Indian Ocean off the west coast of Australia. Nominally located at , it lies about eighty kilometres west of Geraldton, Western Australia...
in Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
to west of Melbourne
Melbourne
Melbourne is the capital and most populous city in the state of Victoria, and the second most populous city in Australia. The Melbourne City Centre is the hub of the greater metropolitan area and the Census statistical division—of which "Melbourne" is the common name. As of June 2009, the greater...
. Despite their name, they are not grouper
Grouper
Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes.Not all serranids are called groupers; the family also includes the sea basses. The common name grouper is usually given to fish in one of two large genera: Epinephelus...
s, but wrasse
Wrasse
The wrasses are a family, Labridae, of marine fish, many of which are brightly colored. The family is large and diverse, with over 600 species in 82 genera, which are divided into nine subgroups or tribes....
s (family Labridae).
The thick bodied blue gropers have peg teeth, heavy scales, a large tail and thick lips. Juveniles are brown to green brown. Adult females are brown to reddish-brown. Each scale may have a darker red spot. The adult males have the bright blue colouring that give the fish their name. The blue can range from deep navy
Navy blue
Navy blue is a very dark shade of the color blue which almost appears as black. Navy blue got its name from the dark blue worn by officers in the British Royal Navy since 1748 and subsequently adopted by other navies around the world....
to cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....
blue, and there may also be darker or yellow-orange spots or lines around the eyes.
All blue gropers begin their life as females. As they mature, they go through an initial phase, in which they may be male or female, before developing their adult colouring and reaching the terminal phase. Eastern blue gropers have been known to grow to 1.2 metres (4 ft) in length and weights of 22 kilograms, although fish over 15 kg are rare. The western species is larger, reaching 1.6 m and 40 kg.
The fish live in a variety of coastal waters, especially exposed reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s. The Western blue groper lives in water 5–65 m deep, and the eastern species from the shallows up to 40 m deep. They feed on invertebrates such as sea urchin
Sea urchin
Sea urchins or urchins are small, spiny, globular animals which, with their close kin, such as sand dollars, constitute the class Echinoidea of the echinoderm phylum. They inhabit all oceans. Their shell, or "test", is round and spiny, typically from across. Common colors include black and dull...
s, crab
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
s and mussel
Mussel
The common name mussel is used for members of several families of clams or bivalvia mollusca, from saltwater and freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other edible clams, which are often more or less rounded or oval.The...
s. For the eastern species, spawning occurs from July until October, in estuarine
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....
seagrass
Seagrass
Seagrasses are flowering plants from one of four plant families , all in the order Alismatales , which grow in marine, fully saline environments.-Ecology:...
beds, where the juveniles are usually found.
In 1998, the Eastern blue groper was made the state fish emblem of New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...
.