The Golden Perch, Macquaria ambigua is an Australian native freshwater fish, primarily of lowland reaches of the Murray-Darling river system, but also known to push some way into upland reaches as well. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms. ... Phyla Porifera (sponges) Ctenophora (comb jellies) Cnidaria Placozoa Subregnum Bilateria  Acoelomorpha  Orthonectida  Rhombozoa  Myxozoa  Superphylum Deuterostomia     Chordata (vertebrates, etc. ... Typical Classes Subphylum Urochordata - Tunicates Ascideiacea Thaliacea Larvacea Subphylum Cephalochordata - Lancelets Subphylum Myxini - Hagfishes Subphylum Vertebrata - Vertebrates Petromyzontida - Lampreys Placodermi (extinct) Chondrichthyes - Cartilaginous fishes Acanthodii (extinct) Actinopterygii - Ray-finned fishes Actinistia - Coelacanths Dipnoi - Lungfishes Amphibia - Amphibians Reptilia - Reptiles Aves - Birds Mammalia - Mammals Chordates (phylum Chordata) include the vertebrates, together with... Orders See text The Actinopterygii are the ray-finned fish. ... Families many, see text The Perciformes, also called the Percomorphi or Acanthopteri, include about 40% of all fish and are the largest order of vertebrates. ... Genera Bathysphyraenops (disputed) Bostockia Coreoperca Edelia Gadopsis Guyu Howella Lateolabrax Maccullochella Macquaria Nannatherina Nannoperca Percichthys Siniperca The Family Percichthyidae are known as the Temperate perches. ... In biology, binomial nomenclature is a standard convention used for naming species. ... Sir John Richardson (1787 - 1865) was a Scottish naval surgeon, naturalist and arctic explorer. ... Groups Conodonta Hyperoartia Petromyzontidae (lampreys) Pteraspidomorphi (early jawless fish) Thelodonti Anaspida Cephalaspidomorphi (early jawless fish) Galeaspida Pituriaspida Osteostraci Gnathostomata (jawed vertebrates) Placodermi Chondrichthyes (cartilaginous fish) Acanthodii Osteichthyes (bony fish) Actinopterygii (ray-finned fish) Sarcopterygii (lobe-finned fish) Actinistia (coelacanths) Dipnoi (lungfish) A fish is a poikilothermic (cold-blooded)* water-dwelling... A branch of the Murray in its middle reaches, near Howlong, New South Wales The Murray River is Australias second-longest river in its own right (the longest being its tributary the Darling). ... The Darling in unusually good condition, near Bourke The Darling River is the longest river in Australia, flowing 2,739km from northern New South Wales to its confluence with the Murray River at Wentworth, New South Wales. ...

Their genus name appears to have been derived from the Macquarie River (=Macquaria), for reasons not clear, while their specific name derives from the original meaning of the Latin word ambigua which is 'two sides'. This is a reference to the strong lateral compression adult Golden Perch display.

The Golden Perch is closely related to the Macquarie Perch, Macquaria australasica, which is a speciated, more specialised inhabitant of the upland reaches of the southern Murray-Darling basin. Binomial name Macquaria australasica Cuvier in Cuvier and Valenciennes, 1830 The Macquarie Perch, Macquaria australasica, is an Australian native freshwater fish of the Murray-Darling river system. ...

Description

Golden Perch are medium sized fish, commonly 30–40cm and 1.0–2.0 kg in rivers. Fish in man-made impoundments show much greater average and maximum sizes. In rivers, has been recorded to 9.0 kg, in impoundments to 15.0 kg. Golden Perch have an elongated deep body, laterally compressed, with a sizable mouth, small to moderate sized eyes and distinct curve to the forehead and "hump" above the head. The caudal fin, soft dorsal fin and anal fin are rounded. The spiny dorsal fin is short to moderate in length and strong. Golden Perch vary from in colour from pale silvery-gold (turbid waters) to deep yellow/gold or bronze-black (very clear waters). Fish anatomy is primarily governed by the physical characteristics of water, which is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs light more than does air. ... Dorsal Fin of the Orca A dorsal fin is a fin located on the backs of fishes, whales, dolphins and porpoises. ... Fish anatomy is primarily governed by the physical characteristics of water, which is much denser than air, holds a relatively small amount of dissolved oxygen, and absorbs light more than does air. ...

Golden Perch have a flexible breeding strategy but generally need a spring or summer flood or "fresh" to stimulate spawning. Like most primarily lowland native of the Murray-Darling river system, these floods or freshes appear to be necessary for good survival and recruitment of spawned fish. The Goldern Perch is highly fecund: egg counts for individual females frequently exceed 200,000, with counts in excess of 500,000 being known. The eggs are semi-planktonic, and hatch fairly quickly (24-36 hours).

Like other Macquaria species, sexual dimorphism is present, with females reaching much larger maximum sizes than males. Females also reach sexual maturity at older, larger sizes than males. Female (left) and male Common Pheasant, illustrating the dramatic difference in form between the sexes Sexual dimorphism is the systematic difference in form between individuals of different sex in the same species. ...

Golden Perch are a predator, taking yabbies, shrimps, small fish and aquatic invertebrates. The word crayfish or crawfish can mean:- Sea crayfish, also called spiny lobster. ... Superfamilies and families Alpheoidea Alpheidae - snapping shrimps Barbouriidae Hippolytidae Ogyrididae Atyoidea Atyidae Bresilioidea Agostocarididae Alvinocarididae Bresiliidae Disciadidae Mirocarididae Campylonotoidea Bathypalaemonellidae Campylonotoidae Crangonoidea Crangonoidea Glyphocrangonoidea Galatheacaridoidea Galatheacarididae Nematocarcinoidea Eugonatonotidae Nematocarcinidae Rhynchocinetidae Xiphocarididae Oplophoroidea Oplophoridae Palaemonoidea Anchistioididae Desmocarididae Euryrhynchidae Gnathophyllidae Hymenoceridae Kakaducarididae Palaemonidae Typhlocarididae Pandaloidea Pandalidae Thalassocarididae Pasiphaeoidea Pasiphaeidae Physetocaridoidea Physetocarididae Procaridoidea... Invertebrate is a term coined by Jean-Baptiste Lamarck to describe any animal without a spinal column. ...

Also, Golden Perch continue the trend of native fish of southeast Australia being incredibly long-lived. Longevity is a survival strategy in the often challending Australian environment to ensure that most adults participate in at least one exceptional spawning and recruitment event, which are often linked to unusually wet La Niña years and may only every one or two decades. Maximum recorded age is 26 years. El Niño is also the nickname of Sergio García. ...

Golden Perch are often found in sympatry ("together with") Murray Cod (Maccullochella peelii peelii). Sympatry is one of three theoretical models for the phenomenon of speciation. ... Trinomial name Maccullochella peelii peelii (Mitchell, 1838) The Murray Cod (Maccullochella peelii peelii) is the largest freshwater fish in Australia. ...

Range

Like many Murray-Darling native fish, Golden Perch have crossed into eastern coastal river catchments through natural river capture events. Golden Perch are found naturally in the Fitzroy-Dawson river in central Queensland. Golden Perch have also entered the internal Lake Eyre-Coopers Creek drainage system of Central Australia. Both of these separate populations are likely to be separate species due to isolation from parent Murray-Darling populations, genetic drift and natural selection. The taxonomy of Golden Perch has not been updated to reflect this, although the term Macquaria ambigua oriens, denoting sub-species status, has recently appeared in literature discussing the Fitzroy-Dawson population. The Fitzroy River lies in Central Queensland, Australia. ... Motto: Audax at Fidelis (Bold but Faithful) Nickname: Sunshine State/Smart State Other Australian states and territories Capital Brisbane Government Governor Premier Const. ... Composite Satellite image of Lake Eyre using shortwave infrared, near-infrared, and blue wavelengths. ... Coopers Creek is one of the most famous and yet least visited rivers in Australia. ... Central Australia is a term used to describe the area of land surrounding and including Alice Springs in Australia. ...

Conservation

Wild populations have declined significantly, especially in upper reaches of rivers, due to dams and weirs blocking migration, mitigating floods and freshes, regulating flows and releasing un-naturally cold water ("thermal pollution"), all of which interfere with migration, spawning and recruitment. Golden Perch are extremely migratory and migration appears to have been important in maintaining populations in some reaches of river, usually the upper reaches.

The species is however bred in hatcheries in large numbers and stocked. Concers over genetic diversity issues are growing however.

External links

• Native Fish Australia - Golden Perch page