Oriental Weatherloach, Misgurnus anguillicaudatus (Cantor 1842)

Other Names: Chinese Weatherfish, Japanese Weatherloach, Pond loach, Pond Loach, Weather Loach, Weatherfish

Oriental Weatherloach, Misgurnus anguillicaudatus, photographed in an aquarium. Source: Gunther Schmida. License: All rights reserved


A brownish to yellowish eel-like fish with darker marbling and spots, a pale silvery underside, and usually a small dark blotch on the upper part of the tail base. The species has a cylindrical body, rounded fins, thick fleshy lips, five pairs of barbels around the mouth, a short-based dorsal fin positioned far back on the body above the pelvic fins.

In the wild in Australia, this native of Asia was first recorded in 1980 in the Australian Capital Territory. And, in 1984, the species was found in the Yarra River, Victoria, presumably having either escaped from ponds or been released by aquarists.

The Oriental Weatherloach now occurs in Queensland, New South Wales, the Australian Capital Territory, Victoria and South Australia. There are unconfirmed reports of its existence in the wild in Western Australia.

Video of Oriental Weatherloach in an aquarium 

Cite this page as:
Gomon, M.F. & Bray, D.J. 2020, Misgurnus anguillicaudatus in Fishes of Australia, accessed 27 Sep 2020,

Oriental Weatherloach, Misgurnus anguillicaudatus (Cantor 1842)

More Info


Oriental weatherloach are native to Eastern Asia from Siberia south to northern Vietnam, including Japan. The species has been widely introduced around the world through the ornamental fish trade, and as a food and a live angling bait fish. 

In Australia, the species now occurs in scattered freshwater areas in Queensland, New South Wales, the Australian Capital Territory, Victoria and South Australia. 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. There are unconfirmed reports of Oriental weatherloach in Western Australia.

A habitat generalist, the Oriental Weatherloach may occur in still or gently flowing streams, rivers, lakes, ponds, and billabongs. Although naturally prefering muddy areas with leaf litter, in Australia, it has been found in habitats ranging from clear, upland, cobble-bottomed streams to lowland turbid rivers, streams and billabongs. The species occurs in both vegetated and un-vegetated permanent and ephemeral waters, with  cobble, pebble, gravel, sand, mud and detritus substrates - natural, modified, or degraded. Inividuals may burrow into the detritus. 

The species is tolerant of a wide range of environmental conditions, including oxygen-depleted waters.


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 Australia.


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.


Feeds 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 its spread throughout eastern and southeastern Australia. It is illegal to use any live fin fish as bait in New South Wales freshwaters.

The species is sold as a food fish in many Asian countries..


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.

In Queensland, the species is a restricted noxious fish under the Queensland Biosecurity Act 2014. Individuals are not permitted to keep, feed, give away, sell, or release Oriental Weatherloach into the environment without a permit - and must immediately humanely kill and dispose of them responsibly away from the waterbody.


The Oriental Weatherloach is considered to be a very successful invader, as it is tolerant of a wide range of environmental conditions. The species can survive in oxygen-depleted waters, and out of water, by gulping air and absorbing the oxygen through the hind gut. Also tolerates temperatures of 2-30°C.


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.


Gomon, M.F. & Bray, D.J. 2020


Atlas of Living Australia

Oriental Weatherloach, Misgurnus anguillicaudatus (Cantor 1842)


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

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

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

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. See ref at BHL

Corfield, J., Diggles, B., Jubb, C., McDowall, R.M., Moore, A., Richards, A. & Rowe, D.K. 2008. Review of the impacts of introduced ornamental fish species that have established wild populations in Australia. Prepared for the Australian Government Department of the Environment, Water, Heritage and the Arts. 277 pp.

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.

Hammer, M.P. & Walker, K.F. 2004. A catalogue of South Australian freshwater fishes, including new records, range extensions and translocations. Transactions of the Royal Society of South Australia 128(2): 85-97

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 resource document. Arthur Rylah Institute for Environmental Research, Melbourne. 78 pp.

Kuiter, R.H. 2018. Pictorial guide to Victoria's freshwater fishes. Part 1. E-version. Seaford, Victoria : Aquatic Photographics 1-110.

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

Lintermans, M., Raadik, T., Morgan, D. & Jackson, P. 2008. Overview of the ecology and impact of three alien fish species: Redfin perch, Mozambique mouthbrooder (Tilapia) and Oriental weatherloach. pp. 22-32 in Ansell, D. & Jackson, P. (eds) Emerging issues in alien fish management in the Murray–Darling Basin: statement, recommendations and supporting papers. Proceedings of a workshop held in Brisbane QLD, 30–31 May 2006, Publication No: 16/07, Murray–Darling Basin Commission, Canberra.

McMahon, B.R. & Burggren, W.W. 1987. Respiratory Physiology of Intestinal Air Breathing in the Teleost Fish Misgurnus anguillicaudatus. Journal of Experimental Biology 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., Wang, W.-M. & Yan, J.-l. 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.

Zhao, H. 2012. Misgurnus anguillicaudatus. The IUCN Red List of Threatened Species 2012: e.T166158A1115635. https://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T166158A1115635.en. Downloaded on 27 October 2019.

Quick Facts

CAAB Code:37170001

Biology:Intestinal air-breather

Conservation:IUCN Least Concern


Max Size:20 cm SL

Native:Introduced - noxious species

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