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To survive the long hot summers that characterise the Arid Lands region, native fish in the Eyre Basin must be able to survive in isolated, often small pools. Basin fish Here they have to cope with very high temperatures, low oxygen and extremely are unique with many high salinities (often saltier than sea-). species found only They must also be able to take advantage of periods of flooding to rebuild around Lake Eyre population levels and recolonise newly filled habitats. Around 20 native fish species are found in the – read on to find out more about some of the more common ones…

Recovering from the drought...

Research by the South Australian recover following others can Arid Lands NRM Board and South take many years to recolonise Australian Research and Development catchments and rebuild populations. Institute has revealed that it takes Large floods may be required before many years for all species of fish to some species return to their former recover from drought. habitats. The team tracked the recolonisation At present some species remain in of the Neales catchment after very few waterholes and are at high recent dry conditions reduced the risk of becoming locally extinct. river into only a few pools. The research team hopes to find out Although there have been no large exactly what conditions each fish species floods since the drought, since 2006 needs to survive and recover from large there have been short periods of disturbances such as drought, or from ‘within channel’ flow during relatively impacts that humans may impose in mild wet seasons. the future, such as climate change or While some species are very quick to increased water usage.

SOUTH AUSTRALIAN ARID LANDS NATURAL RESOURCES MANAGEMENT BOARD PAGE 1 Barcoo grunter Carp gudgeon species Retropinna semoni Scortum barcoo Hypseleotris spp. » Grow between 40-60mm, but can » Commonly grow to 200mm » Commonly reach 60mm in length grow larger » Bodies are predominately silver grey, » Range in colours from tans to olives » Translucent with a silver body cavity with lighter sides and belly. A few with a lighter belly. Male fins gain a red and opaque head irregular large spots may be present on colour during spawning season. » Spawn from late winter to early one or both sides of the fish (hard to » Little is known of the Lake Eyre region summer (little is known for the fish in distinguish from Welch’s grunter). gudgeons, but they are thought to the Lake Eyre region) » Spawn in the warmer months – breed in spring and early summer at Form large schools. Found in waterholes flooding is likely necessary for temperatures between 20-24°C and in only the spawning Widespread and found in small and system of Lake Eyre. Found in waterholes of all catchments, creeks in the Cooper Creek catchment. congregating in schools. They can be angled and are excellent eating.

Banded grunter Bony HERRING Cooper Creek Catfish Amniataba percoides Nematalosa erebi Neosiluroides cooperensis » Can grow up to 200mm » Grow to 300mm » Grow up to 600mm » Usually brown to bronze on backs and » Silver with a green tinge on their backs » Pale grey to brown, with dark lighter on sides and belly, has five to and white sides speckling, mottled on sides with a eight vertical bands on each side and » Spawn in spring and summer periods, whitish underbelly yellow fins independently of floods » Little is known on the biology of » No knowledge of the breeding biology Found in most rivers, creeks, lakes this fish in the Lake Eyre region but known to and waterholes in large schools and Found only in large permanent spawn at night when reach distributed in all major Lake Eyre waterholes of the Cooper Creek system 26-33°C regional rivers. Caught by anglers but of the Lake Eyre basin. A good angling Found in rivers in loose schools or not targeted because of poor eating and eating fish. Considered very rare and colonies. Patchy distribution in the qualities. possibly under threat due to its very local and the . distribution. Excellent eating fish.

PAGE 2 Desert Goby Hyrtl’s tandan Lake Eyre Chlamydogobius eremius Macquaria species » Grow to 60mm long » Grow to 350mm (commonly 200mm) » Grow to about 600mm » Colour ranges from tan-brown to a » Range in colour from browns to silver- » Appear yellowish tan on their back, light coloured barring pattern. Bright grey with a white underbelly with nasal becoming lighter on their sides to a blue spot on their first dorsal fin. barbels creamy yellow belly » Spawn from November to March » Breeding occurs between January and » Typically spawn on the first flood of the Found in springs, waterholes (mostly March but this is not known for the season ephemeral) creeks and rivers in the Lake Eyre Region fish Found in most rivers and large creeks; Neales and Diamantina/Warburton Found in most creeks, billabongs and at times abundant in lakes. Widespread Rivers and south around Lake Eyre. pools. Widespread in the Lake Eyre through the Neales/Cooper Creek/ Widespread and quite abundant. region. Diamantina/Georgina catchments. Major angling fish and good eating.

Desert Rainbowfish Lake Eyre Hardyhead Silver tandan Melanotaenia splendida Craterocephalus eyresii Porochilus argenteus » Commonly grow to 80mm » Grows to 100mm » Grow to a maximum size of 350mm » Very colourful. Can appear purplish on » Silver body, appearing pale yellow with (commonly to 200mm) the westward side of Lake Eyre and a greenish mid-lateral stripe » Pale silvery-white with lighter blue-green from the rivers on the east. » Breeding occurs between the months underbelly » Have been observed breeding in late of January and March » Believed to spawn during floods autumn Found in fresh and saline waterholes and Found in Diamantina/Warburton and Found in most waterholes and lakes and lakes. Tolerate salinities up to 100 ppt. Cooper Creek catchments. Taken in all large rivers throughout the Lake More commonly found in the SA region occasionally by anglers. Eyre region. of the Lake Eyre Basin.

SOUTH AUSTRALIAN ARID LANDS NATURAL RESOURCES MANAGEMENT BOARD PAGE 3 Spangled perch Welch’s grunter Western chanda perch Leiopotherapon unicolour Bidyanus welchi Ambassis mulleri » Can grow up to 300mm, commonly » Most reach a length of 250mm but can » Can grow to 60mm found at 150mm grow as large as 375mm » Often translucent with a green to » Predominately silver with bluey brown » Silver-grey in colour with lighter sides silver tinge or golden speckles on their sides and belly » Little is known of its biology but » Spawn from spring to autumn » Spawn through the warmer months but breeding is not linked to flooding The most widespread fish in flooding may be necessary though they use floodwater for being found in most wet habitats Found in rivers and waterholes in dispersal from rivers to springs in small schools. schools and are widespread in eastern Found mostly in clear waterbodies such Distributed in all parts of Lake Eyre catchments. Can be angled readily. as lakes and are widespread in the region. Good angling and eating fish. drainages of including Cooper Creek.

Refuge Waterholes Introduced Species Please take care of the desert GAMBUSIA, MOSQUITO FISH waterholes you visit – each one may be crucial to the survival of native fish Gambusia holbrooki during dry periods. » Up to 60mm long Each year, the rivers in the South » Olive, tan or grey, with silver sides Australian section of the Lake (bluish tinge) and bellies Eyre Basin dry up into a series of » Breed all year (excluding winter) in disconnected pools. During very dry the Lake Eyre region seasons, or extended periods of drought, Form large populations in waterholes only a few pools remain. and springs. Found in shallow still To survive in these desert systems waters with abundant vegetation or fish must be able to access refuge muddy waterholes. Widespread and waterholes and survive in some of the distributed in the Neales, Diamantina harshest conditions on earth. Rivers and Cooper Creek. Spreading Some of the most important refuges for throughout the Lake Eyre region. native fish include Cullyamurra waterhole Gambusia are highly invasive and near Innamincka and Algebuckina aggressive fish that out-compete waterhole near . native fish and frogs. Gambusia should never be kept, moved or added to any waterways, dams or wells. If Further information you find Gambusia in the wild, please SA Arid Lands Natural Resources report it to SARDI 8303 9400. Management Board PO BOX 2227 Port Augusta SA 5700 8648 5977 [email protected] www.saalnrm.sa.gov.au

Compiled by Dr Dale McNeil, David Schmarr and PAGE 4 Dean Hartwell, SARDI, Aquatic Sciences, November 2009