Oriental Weatherloach, Misgurnus anguillicaudatus (Cantor 1842)

Other Names: Pond loach, Pond Loach, Weather Loach

Oriental Weatherloach, Misgurnus anguillicaudatus. Source: Yuichi Kano, FiMSeA / http://ffish.asia. License: CC by Attribution


This native of Asia was first recorded from the Yarra River, Victoria, in 1984, presumably having either escaped from ponds or been released by aquarists.

Identifying features:
• Body eel-like, mouth small, narrow, and surrounded by 5 pairs of barbels; lips thick and fleshy
• Dorsal fin single, short-based, positioned far back on body above the pelvic fin origin.
• Pectoral fins triangular with a stout spine
• Body brownish to yellowish with darker greenish, greyish or blackish marbling above, underside pale; upper part of tail base with a dark blotch.

The Oriental Weatherloach is now widespread in Victoria, New South Wales, the Australian Capital Territory and Queensland. It has recently been recorded from South Australia, and there are unconfirmed reports of its existence in the wild in Western Australia.

Video of Oriental Weatherloach in an aquarium 

Cite this page as:
Martin F Gomon & Dianne J Bray, Misgurnus anguillicaudatus in Fishes of Australia, accessed 29 Jan 2020,

Oriental Weatherloach, Misgurnus anguillicaudatus (Cantor 1842)

More Info


Oriental weatherloach are native to China, Siberia, Korea, Hainan and Japan.  Introduced from Asia. The species now occurs in many freshwaters areas in New South Wales, the Australian Capital Territory and Victoria. In February 2011, the Oriental Weatherloach was recorded for the first time in South Australia on the Chowilla Floodplain. Following 2011-2012, Oriental Weatherloach spread into and throughout the South Australian Murray–Darling Basin region. Oriental weatherloach have also been recorded from coastal areas of northeast Queensland, and there are unconfirmed reports from Western Australia.

Inhabits tropical and temperate freshwater streams, rivers and lakes, preferring still or gently flowing water over sandy or muddy bottoms into which it burrows. It is tolerant of a wide range of conditions.


Meristic features: Dorsal fin 9; Anal fin 7; Caudal fin 9; Pectoral fin 10; Pelvic fin 6.

Body elongate, almost cylindrical, with 5 pairs of barbels around the mouth. Skin mucous-covered with reduced embedded scales. Dorsal fin single, short-based and positioned on the middle of the back; caudal fin elongate, rounded.

Females have a rounded pectoral fin, whereas in males, the pectoral fin has a triangular or square-cut shape and the second pectoral-fin ray of males is thickened and elongate.


Grows to about 20 cm SL in Australian waters.


Overall greenish-brown to yellowish with darker mottling above and paler ventrally, with a rosy or purplish hue. The base of the tail has a prominent black spot.


This omnivorous species preys on a range of invertebrates, including insect larvae, rotifers, gastropod and bivalve molluscs, micro-crustaceans, and also ingests algae and detritus.


The species is a multiple spawner, and during summer, females lay between 4000 and 8000 small red adhesive eggs onto aquatic plants or the muddy bottom. The eggs are 1.5 mm in diameter and hatch after 2-3 days. Oriental Weatherloach mature at around 100 mm TL.

Individuals can survive out of water by gulping air and absorbing oxygen through the hind gut. During times of drought, Oriental Weatherloach burrow into the muddy bottom, remaining there for long periods until conditions improve. They can also tolerate temperatures ranging between 2 and 30 degrees Celsius. As a result, they are able to move limited distances out of water to colonise new areas.

This nocturnal bottom dweller is typically found in still waters with sandy or muddy substrates.

With a lifespan in captivity of 13+ years, a single female may lay up to 100,000 eggs in her lifetime. Due to their relatively high fecundity, hardiness and mobility there is a high risk of self sustaining populations becoming established once the weatherloach is introduced into new areas.

The  Oriental Weatherloach accomplishes intestinal air-breathing by swallowing air and passing it down the length of the gut unidirectionally. The intestine is characteristically inflated with air even during feeding, with the intestinal fluid limited to a surface film. The gastrointestinal tract of the Oriental Weatherloach is highly modified for gas exchange, with the posterior intestine (two-thirds of the total gut length) having a well-vascularized stratified epithelium with intraepithelial capillaries suitable for gas exchange (McMahon and Burggren, 1987; Gonçalves et al., 2007; Wilson and Castro 2010).


The Oriental Weatherloach may have been released into Australian waterways by aquarists or by escaping from ponds.

It is a popular live bait fish used by anglers, and escapees may have contributed to the spread of this species throughout eastern and southeastern Australia. It is illegal to use any live fin fish as bait in NSW freshwaters.

The species is sold as a food fish in many Asian countries. Oriental Weatherloach are widely eaten in eastern Asia and have been introduced into Mexico and the Philippines for aquaculture.


The Oriental Weather Loach is a Declared Noxious Aquatic Species under the Victorian Fisheries Act 1995, and should not be returned to the water after capture.

The species is also listed as a Class 1 Noxious Species in NSW, which prohibits its sale and possession, and heavy penalties apply.


The species is tolerant of a wide range of environmental conditions, and can survive for long periods out of water by gulping air and absorbing the oxygen through its hind gut. It is considered to be a very successful invader. 

Tolerates temperatures between 2 and 30°C and can breathe air to supplement respiratory requirements in oxygen depleted waters.


The standard fish name 'weatherloach' refers to the species reported habit of becoming restless during changes in barometric pressure.

Species Citation

Cobitis anguillicaudata Cantor, 1842, Ann. Mag. Nat. Hist. (1)9(53): 481-493. Type locality: Chusan Island, China.


Martin F Gomon & Dianne J Bray

Oriental Weatherloach, Misgurnus anguillicaudatus (Cantor 1842)


Allen, G.R., Midgley, S.H. & Allen, M. 2002. Field Guide to the Freshwater Fishes of Australia. Perth : Western Australian Museum 394 pp.

Allen, S. 1984. Occurrence of juvenile weatherfish Misgurnus anguillicaudatus (Pisces: Cobitidae) in the Yarra River. Victorian Naturalist 101: 240–242 (first confirmed naturalised population in Australia)

Arthington, A.H. & F. McKenzie, 1997. Review of impacts of displaced/introduced fauna associated with inland waters. Australia: State of the Environment Technical Paper Series (Inland waters), Department of the Environment, Canberra (Australia). 69 pp.

Burchmore, J., R. Faragher & G. Thorncraft. 1989. Occurrence of the introduced oriental weather loach (Misgurnus anguillicaudatus) in the Wingecarribee River, New South Wales. p. 38-46. In: D.A. Pollard (ed.) Introduced and translocated fishes and their ecological effects. Proceedings of the Australian Society for Fish Biology Workshop No. 8. Magnetic Island. 24-25 August 1989.

Cantor, T.E. 1842. General features of Chusan, with remarks on the flora and fauna of that island. Ann. Mag. Nat. Hist. (1)9(53): 481-493.

Dove, A.D.M. & Ernst, I. 1998. Concurrent invaders—four exotic species of Monogenea now established on exotic freshwater fishes in Australia. International Journal for Parasitology 28(11): 1755-1764.

Fredberg, J.F., Thwaites, L.A. & Earl, J. (2014). Oriental weatherloach, Misgurnus anguillicaudatus, in the River Murray, South Australia: A Risk Assessment. Report to Biosecurity SA. South Australian Research and Development Institute (Aquatic Sciences), Adelaide. SARDI Publication No. F2014/000381-1. SARDI Research Report Series No. 786. 115pp.

Gonçalves, A.F., Castro, L.F.C., Pereira-Wilson, C., Coimbra, J. & Wilson, J.M. 2007. Is there a compromise between nutrient uptake and gas exchange in the gut of Misgurnus anguillicaudatus, an intestinal air-breathing fish? Comp. Biochem. Physiol. 2D: 345-355.

Graham, J.B. 1997. Air-Breathing Fishes: Evolution, Diversity and Adaptation. San Diego, CA: Academic Press.

Keller, R.P. & Lake, P.S. 2007. Potential impacts of a recent and rapidly spreading coloniser of Australian freshwaters: Oriental weatherloach (Misgurnus anguillicaudatus). Ecology of Freshwater Fish 16: 124–132

Koster, W.M., Raadik, T.A. & Clunie, P. 2002. Scoping study of the potential spread and impact of the exotic fish Oriental weatherloach in the Murray-Darling Basin, Australia: a draft management strategy. Arthur Rylah Institute for Environmental Research, Melbourne. 15 pp.

Koster, W.M., Raadik, T.A. & Clunie, P. 2002. Scoping study of the potential spread and impact of the exotic fish Oriental weatherloach in the Murray-Darling Basin, Australia: a resource document. Arthur Rylah Institute for Environmental Research, Melbourne. 78 pp.

Lintermans, M. 1993. Oriental Weatherloach, Misgurnus anguillicaudatus,  in The Cotter River: A New Population In The Canberra Region  L. a. P. Department of the Environment. ACT, ACT Parks and Conservation Service.

Lintermans, M. & J. Burchmore 1996. Cobitidae. p. 114 in McDowall, R.M. (ed.) Freshwater Fishes of South-eastern Australia. Sydney : Reed Books 247 pp.

McMahon, B.R. & Burggren, W.W. 1987. Respiratory Physiology of Intestinal Air Breathing in the Teleost Fish Misgurnus anguillicaudatus. J. Exp. Biol. 133: 371-393.

Raadik, T.A. & W. Koster. 2004. Potential spread and impact of a little known alien fish introduced  into Australia: the Oriental weatherloach (Misgurnus  anguillicaudatus). New Zealand Journal of Marine and Freshwater Research 38(3): 562

Raadik, T.A., Koster, W. & Lintermans, M. 2005. Shame file: alien creature feature No. 1, Oriental weatherloach Misgurnus anguillicaudatus (Cantor, 1842) (Pisces: Cobitidae). Australian Society for Fish Biology Newsletter 35(1): 55–58.

Wang, M., W.-m. Wang & J.-l. Yan, 2001. Comparative studies of on the age and growth of Misgurnus anguillicaudatus and Paramisgurnus dabryanus. Reservoir Fisheries 21(1): 7-9.

Wegener, I.K. & Suitor, L. 2014. Distribution of the Oriental Weatherloach (Misgurnus anguillicaudatus) in the South Australian region of the Murray–Darling Basin – Update 2014: From specimens collected by Natural Resources SA Murray – Darling Basin, Department of Environment, Water and Natural Resources, Berri.

Quick Facts

CAAB Code:37170001

Biology:Intestinal air-breather

Conservation:A declared Noxious Species


Max Size:20 cm SL


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