The golden perch (''Macquaria ambigua'') is a medium-sized, yellow or gold-coloured species of

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 ...

freshwater fish Freshwater fish are those that spend some or all of their lives in fresh water, such as rivers and lakes, with a salinity of less than 1.05%. These environments differ from marine conditions in many ways, especially the difference in levels of s ...

found primarily in the Murray-Darling River system, though a

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

is found in the

Lake Eyre Lake Eyre ( ), officially known as Kati Thanda–Lake Eyre, is an endorheic lake in east-central Far North South Australia, some north of Adelaide. The shallow lake is the depocentre of the vast endorheic Lake Eyre basin, and contains the ...

Cooper Creek The Cooper Creek (formerly Cooper's Creek) is a river in the Australian states of Queensland and South Australia. It was the site of the death of the explorers Burke and Wills in 1861. It is sometimes known as the Barcoo River from one of its t ...

system, and another subspecies, suspected to be ancestral to all other populations, is found in the Fitzroy River system in

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

. Other common names for golden perch are "goldens", “yellowbelly” and "callop", the last generally used only in

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

. Golden perch are not a true

perch Perch is a common name for fish of the genus ''Perca'', freshwater gamefish belonging to the family Percidae. The perch, of which three species occur in different geographical areas, lend their name to a large order of vertebrates: the Percif ...

, which belongs to the genus ''Perca'' from the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Percidae The Percidae are a family of ray-finned fish, part of the order Perciformes, which are found in fresh and brackish waters of the Northern Hemisphere. The majority are Nearctic, but there are also Palearctic species. The family contains more than ...

, but a member of the

Percichthyidae The members of the family Percichthyidae are known as the temperate perches. They belong to the order Perciformes, the perch-like fishes. The name Percichthyidae derives from the Latin ''perca'' for perch and Ancient Greek ἰχθύς, ''ichthy ...

(

temperate perch The members of the family Percichthyidae are known as the temperate perches. They belong to the order Perciformes, the perch-like fishes. The name Percichthyidae derives from the Latin ''perca'' for perch and Ancient Greek ἰχθύς, ''ichthy ...

) family. This relatively widespread and widely

stock In finance, stock (also capital stock) consists of all the shares by which ownership of a corporation or company is divided.Longman Business English Dictionary: "stock - ''especially AmE'' one of the shares into which ownership of a company ...

ed species is an important

angling Angling is a fishing technique that uses a fish hook or "angle" (from Old English ''angol'') attached to a fishing line to tether individual fish in the mouth. The fishing line is usually manipulated via a fishing rod, although rodless techniqu ...

sport fish Game fish, sport fish or quarry refer to popular fish pursued by recreational anglers, and can be freshwater or saltwater fish. Game fish can be eaten after being caught, or released after capture. Some game fish are also targeted commercial ...

in Australia.

Description

Golden perch are medium-sized fish, commonly 30–40 cm and 1–2 kg in rivers. Fish from rivers are smaller and somewhat streamlined — fish in man-made impoundments are much deeper-bodied and show much greater average and maximum sizes. In rivers, has been recorded to 9 kg, in impoundments to 15 kg. A 24-kg fish caught from Kow Swamp,

Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seychelle ...

in the early 1900s, and labelled and sold as a "Murray perch", is often referred to as the largest recorded golden perch, but this record is doubtful — this record grossly exceeds all other size records for golden perch, and the specimen in question is far more likely to have been a Murray cod (''Maccullochella peelii''), which grow to far larger sizes than golden perch. Golden perch have an elongated, deep but laterally compressed body, with a sizable mouth, small to moderate-sized eyes, a distinct curve to the forehead, and a distinct "hump" above the head. The opercula or gill covers possess a small, flat spine sharp enough to cut unwary fishermen's fingers. The

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

, soft

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

, and

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

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). Golden perch 2

Taxonomy

The genus name ''Macquaria'' derives from the

Macquarie River The Macquarie River - Wambuul is part of the Macquarie– Barwon catchment within the Murray–Darling basin, is one of the main inland rivers in New South Wales, Australia. The river rises in the central highlands of New South Wales near the ...

, where the first species in the genus, the

Macquarie perch The Macquarie perch (''Macquaria australasica'') is an Australian native freshwater fish of the Murray-Darling river system. It is a member of the family Percichthyidae and is closely related to the golden perch (''Macquaria ambigua''). The ...

(''M. australasica''), was collected. However, the genus name ''Macquaria'' was applied to golden perch much later. The naturalist Richardson actually named golden perch ''Datnia ambigua'' and applied the specific name ''ambigua'' (Latin for "doubtful") to the species because, as he states in his species description, he could not decide in which of two genera to place it, ''Dules'' (now ''

Kuhlia The flagtails (' or ' in the Hawaiian language) are a family (Kuhliidae) of perciform fish of the Indo-Pacific area. The family consists of several species in one genus, ''Kuhlia''. Most are euryhaline and often found in brackish water, but th ...

'' species) or ''Datnia'' (now various

Terapontidae Grunters or tigerperches are ray-finned fishes in the Family (biology), family Terapontidae (also spelled Teraponidae, Theraponidae or Therapontidae). This family is part of the Superfamily (taxonomy), superfamily Percoidea of the Order (biology ...

species): :“I have had much doubt as to whether this fish should be placed in the genus ''Dules'', or ''Datnia''. It agrees with the group of ''Dules'' that has two opercular points, in the number of dorsal rays, and in the presence of palatine teeth, but in general habit it is more like ''Datnia'', strongly resembling it in the strength of its dorsal and anal spines, and in the number of rays in the anal. The only two specimens .5 and 14 inches standard lengthI had the opportunity of examining are dried, and are both mutilated in the caudal fin, so that I am unable to describe the form of that member, and can give no anatomical details.” This choice of specific name was unwittingly appropriate. Golden perch are neither a khulid nor a terapontid, and Richardson also erroneously stated the golden perch's habitat was "

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

", when in fact the species is not found in that state. (This error was corrected, presumably by Richardson himself, in at least one reprint of the publication in question.)

Range

Golden perch are native primarily to lowland reaches of the

Murray Murray may refer to: Businesses * Murray (bicycle company), an American manufacturer of low-cost bicycles * Murrays, an Australian bus company * Murray International Trust, a Scottish investment trust * D. & W. Murray Limited, an Australian who ...

– Darling River system, but also extend far into slope habitats and occasionally even lower upland reaches. In the Murray–Darling system golden perch are often found in

sympatry In biology, two related species or populations are considered sympatric when they exist in the same geographic area and thus frequently encounter one another. An initially interbreeding population that splits into two or more distinct species sh ...

with Murray cod. The ''Macquaria'' perches, of which golden perch are one, continue the trend present in Murray–Darling native fish genera of diversification into more generalist

lowland Upland and lowland are conditional descriptions of a plain based on elevation above sea level. In studies of the ecology of freshwater rivers, habitats are classified as upland or lowland. Definitions Upland and lowland are portions of ...

species and more specialist upland species. Golden perch, ''M. ambigua'', represent the lowland species, while the closely related Macquarie perch, ''M. australasica'', is the more specialised upland species which used to inhabit the upland reaches of the southern Murray–Darling basin, although this endangered species has now been almost wholly displaced by introduced trout species, dams, and associated effects such as cold-water pollution, and habitat degradation/modification. Like many Murray–Darling native fish, golden perch have crossed river catchments through natural river capture/connection events. Golden perch are found naturally in the Fitzroy–Dawson River in central

and the internal

–

drainage system of

Central Australia Central Australia, also sometimes referred to as the Red Centre, is an inexactly defined region associated with the geographic centre of Australia. In its narrowest sense it describes a region that is limited to the town of Alice Springs and i ...

. The fish has also been successfully introduced to other river systems in the Northern Territory, Queensland, and New South Wales, confusing studies of the natural range. Introductions into Western Australia have been unsuccessful. Both of these separate populations are at least

, possibly separate species, due to isolation from 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 subspecies status, has recently appeared in literature discussing the Fitzroy–Dawson population. Some research indicates the Fitzroy River population is the ancestral golden perch population.

Reproduction and biology

In the Murray River, wild male golden perch generally reach sexual maturity at 3 years of age and 32.5 cm in length, and wild female golden perch at 4 years of age and 40 cm in length. The latter fact is a concern given that minimum size limits for the species are currently less than 40 cm, at 30 cm. Originally, temperatures close to 24 °C were considered necessary for golden perch to spawn, but as with all Murray-Darling fish species, multiple field studies have shown that their "required" spawning temperature is flexible and that they can and do spawn at lower temperatures. In the Barmah Forests region of the Murray River, for instance, fertilised drifting golden perch eggs have been netted in water temperatures as low as 16.9 degrees Celsius (full range 16.9 to 24.7 degrees). Golden perch have a flexible breeding strategy but generally (but not always) require a spring or summer flood or "fresh" (temporary, within-channel increase in flow) to stimulate spawning. Like some other primarily lowland native fish species of the Murray–Darling river system, these floods or freshes appear to be necessary for good survival and recruitment of spawned fish. Very small freshes appear to be sufficient for some spawning and recruitment, however. Golden perch are highly fecund; females between 2.2 and 2.4 kg produce about half a million eggs per spawning event, with fish above 2.5 kg producing well in excess of this number. The eggs are generally

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

ic, and hatch fairly quickly (24 to 36 hours). Like other ''Macquaria'' species,

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

is present, with females reaching much larger maximum sizes than males. Females also reach sexual maturity at older ages and larger sizes than males. Very long migrations are part of the golden perch's ecology, particularly preceding spawning. Adult fish have been recorded migrating well over 1,000 km when flood conditions allow passage over weirs and other man-made obstructions. Smaller migrations are important in the ecology and dispersal of juvenile fish.Mallen-Cooper & Stuart, 2003 The evidence suggests that before European settlement, huge shoals of golden perch roamed the entire lowland and slope reaches of the vast Murray-Darling River system, unimpeded. Thus, the gradual loss of fish passage through the numerous dams, weirs, locks, and other barriers (estimated at 4,000 in the Murray-Darling system) now present has had severe impacts on the species. Some major weirs have been remediated to provide fish passage, however. Golden perch have unusually broad temperature limits, from 4 to 37 °C, and unusually high salinity limits for a freshwater fish, up to 33 parts per thousand. Golden perch continue the trend, among many native fish of southeast Australia, of being very long-lived. Longevity is a survival strategy in the often challenging Australian environment which ensures that most adults participate in at least one exceptional spawning and recruitment event. These events are often linked to unusually wet ''

La Niña La Niña (; ) is an oceanic and atmospheric phenomenon that is the colder counterpart of as part of the broader El Niño–Southern Oscillation (ENSO) climate pattern. The name ''La Niña'' originates from Spanish for "the girl", by an ...

'' years and may only occur every one or two decades. Maximum recorded age is 26 years.

Diet

Adult golden perch are

carnivores A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

, feeding on smaller fish and macrocrustaceans, including yabbies,

shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...

frog A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...

s, small fish, and aquatic

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

Angling

Generally a very good angling species (though renowned for being "moody"), golden perch are fished throughout their range. Baits include small yabbies and shrimp, as well as various types of deeper-running lures. Recreational harvest of the species is suspected to be significant.

Conservation

Wild populations have declined significantly, and a number of populations lost in upper reaches of rivers, due to dams and weirs blocking migration, mitigating floods and freshes, regulating flows, and releasing unnaturally cold water ("thermal pollution"), all of which interfere with migration, spawning, and recruitment. They are listed under the Victorian

Flora and Fauna Guarantee Act 1988 The ''Flora and Fauna Guarantee Act 1988'', also known as the ''FFG Act'', is an act of the Victorian Government designed to protect species, genetic material and habitats, to prevent extinction and allow maximum genetic diversity within the Au ...

and classified as "Vulnerable" for management purposes. Golden perch are extremely migratory and migration appears to have been important in maintaining populations over the length of rivers, particularly the upper reaches. Weirs are proving to be a more significant threat to golden perch than first thought, with a 2006 study showing that about 90% of golden perch larvae passing through undershot weirs are killed.Baumgartner, L.J., Reynoldson, N. and Gilligan, D.M. (2006). Mortality of larval Murray cod (''Maccullochella peelii peelii'') and golden perch (''Macquaria ambigua'') associated with passage through two types of low-head weirs. ''Marine and Freshwater Research'' 57: 187–191 The species is bred in hatcheries, though, in large numbers, and stocked. Concerns over genetic diversity issues are growing.

References

* * King AJ, Tonkin Z and Mahoney J (2008). Environmental flow enhances native fish spawning and recruitment in the Murray River, Australia. ''River Research and Applications''. DOI: 10.1002/rra.1209 * Koehn, J. D. and Harrington, D. J. (2005). Collection and distribution of early life stages of the Murray cod (''Maccullochella peelii peelii'') in a regulated river. ''Australian Journal of Zoology'' 53: 137–144. * Lake, J.S. (1967). Rearing experiments with five species of Australian freshwater fishes. I. Inducement to spawning. ''Australian Journal of Marine and Freshwater Research'' 18: 137–153. * Lintermans M (2007). ''Fishes of the Murray-Darling Basin: An introductory guide''. Murray-Darling Basin Commission, Canberra. * * Richardson, John. ''Ichthyology of the voyage of H.M.S. Erebus & Terror, under the command of Captain Sir James Clark Ross, R.N., F.R.S.'' LONDON: M.DCCC.XLIV—M.DCCC.XLVIII 844–1848 Longman, Brown, Green and Longmans. * Rowland, S. J. (1996). Development of techniques for the large-scale rearing of the larvae of the Australian freshwater fish golden perch, ''Macquaria ambigua'' (Richardson, 1845). ''Marine and Freshwater Research'' 47: 233–242.

External links

Native Fish Australia - golden perch page
{{Taxonbar, from=Q783248

golden perch The golden perch (''Macquaria ambigua'') is a medium-sized, yellow or gold-coloured species of Australian freshwater fish found primarily in the Murray-Darling River system, though a subspecies is found in the Lake Eyre-Cooper Creek system, an ...

Murray-Darling basin Freshwater fish of Australia Taxa named by John Richardson (naturalist)