Longfin Eel, Anguilla reinhardtii Steindachner 1867

Other Names: Australian Longfinned Eel, Conger Eel, Freshwater Eel, Long-fin Eel, Longfinned Eel, Long-finned Eel, Marbled Eel, River Eeel, River Eel, Speckled Longfin Eel, Spotted Eel

A Longfin Eel, Anguilla reinhardtii, from Angusvale, Gippsland Lakes, Mitchell River National Park, Victoria, November 2014. Source: David Paul / Museums Victoria. License: CC by Attribution-NonCommercial

Summary:

A large mottled or marbled eel with olive-green to brown markings, and a paler underside. Longfin Eels spend most of their lives in freshwater, migrating to spawn in deep waters of the Coral Sea. As their transparent leptocephalus larvae grow, they metamorphose into glass eels, then pigmented elvers as they reach coastal waters. Longfin Eels then develop into yellow eels, before transforming into silver eels and returning to freshwater streams.

Great video of "Ellie", a Longfin Eel in the Sydney Botanic Gardens.

Migrating glass eels - juvenile Longfin Eels - in a very small mangrove creek at the northern end of Palm Cove, Cairns, Australia.

River Monsters: The Longfin Eel Migration in New Zealand.

Longfin Eels in New Zealand.

Cite this page as:

Gomon, M.F. & Bray, D.J. 2021, Anguilla reinhardtii in Fishes of Australia, accessed 20 Apr 2024, https://fishesofaustralia.net.au/Home/species/1426

Longfin Eel, Anguilla reinhardtii Steindachner 1867

More Info

Distribution	Widespread in the coastal drainages of eastern Australia from Cape York, Queensland, to Melbourne, Victoria, and northern and eastern Tasmania; also Lord Howe Island in the Tasman Sea. Elsewhere the species occurs in the tropical and temperate Southwestern Pacific: New Caledonia, northwestern New Zealand, Papua New Guinea and Vanuatu. Longfin Eels prefer flowing waters, and commonly occur in riverine habitats, from river mouths to headwater streams. They also inhabit in lakes, swamps and floodplains, and deep freshwater reservoirs. The species is catadromous and adults migrate to the deep oceanic waters of the Coral Sea below 400 m to spawn. Glass eels and elvers are found in estuarine areas, before moving upstream as silver eels.
Features	Pectoral fins 16-20; Vertebrae 104-110 Body large, elongate, cylindrical (depth 6-8% SL); head moderately small (12-18% SL); eyes small; mouth large, horizontal, usually reaching just beyond eyes; teeth fine, a narrow band in jaws and on vomer, vomerine patch about as long as bands laterally in jaws; maxillary teeth separated by a toothless groove; gill openings small, just forward of lower half of pectoral fin bases; lateral line straight, not associated with scales. Scales tiny, elongate, embedded, arranged in a basket-work pattern. Dorsal, caudal and anal fins united to form one continuous fin; dorsal fin origin well in front of vertical line drawn through anus (distance between the two 8-14% TL); pectoral fins prominent; ventral fins absent.
Size	Although Longfin Eels commonly reach lengths of about 100-150 cm and may weigh 1-2 kg, land-locked individuals that are prevented from migrating downstream may reach 300 cm and weigh up to 22 kg. Males are generally smaller than females, growing to about 65 cm and weighing about 600 g.
Colour	Adults and elvers are distinctly mottled or marbled with olive-green to brown markings, and a paler underside. Adults returning to sea are overall silvery, with a mottled underside, and often yellowish pectoral fins. Leptocephali and glass eels are mostly transparent with the muscle bands visible internally.
Feeding	Longfin eels are carnivores, and are the top predator in many habitats. They usually feed at night on fishes, crustaceans, molluscs and insects, and occasionally juvenile waterfowl.
Biology	The sexes separate and Pease et al (2004) found no evidence of hermaphroditism in Longfin Eels. The species is catadromous, and adults may remain in freshwater environments for more than 50 years before migrating to the Coral Sea to spawn in depths greater than 400 m. The small pelagic eggs float towards the surface. The leptocephalus larvae are transparent, elongate, compressed and leaf-like. Leptocephali are believed to be transported to the continental shelf by oceanic currents before metamorphosing into transparent eel-shaped "glass eels", followed by pigmented elvers as they reach coastal waters. During this metamorphosis, a reduction in body length and width and loss of teeth occurs. Glass eels enter estuaries at about 58 mm TL, where they undergo physiological changes to cope with reduced salinities. The eels develop rapidly as they migrate up estuaries, and become fully pigmented "elvers" with teeth and well-developed stomachs. This is followed by a second upstream migration into freshwater as silver eels with a dark dorsal surface and pale underside.
Fisheries	Freshwater eels have long been a popular food source for Aboriginal people in eastern Australia and have strong cultural significance. Eels have been caught with a variety of methods, including fish traps, lures, hook and line and natural poisons derived from plants. Longfin Eels have been targeted commercially in Australia since the 1950's or 60's. Although four commercial fisheries target Longfin Eels in eastern Australia, most are harvested in the estuarine trap fishery which targets large yellow eels. Relatively small numbers of glass eels (post-larvae migrating from the sea to freshwaters) are caught with fyke nets in upper estuarine areas to be grown up in the aquaculture industry. Other small fisheries targets small male yellow and juvenile eels and larger eels in impoundments. Most eels caught in the estuarine trap fishery are exported live to China (including Hong Kong) and elsewhere in Asia.
Conservation
Remarks	The Longfin Eel may live to more than 50 years.
Similar Species	Readily distinguished from the Shortfin Eel, Anguilla australis, by its spotted body pattern and length of the dorsal fin, which commences well in front of the anal fin.
Etymology	The species is presumably named in honour of Danish zoologist and herpetologist Johannes Theodor Reinhardt.
Species Citation	Anguilla reinhardtii Steindachner 1867, Sber. Akad. Wiss. Wien 55(1): 15, Figs. a-b. Type locality: Fitzroy River, Rockhampton, Queensland, Australia.
Author	Gomon, M.F. & Bray, D.J. 2021
Resources	Atlas of Living Australia Australian Faunal Directory Catalog of Fishes

Longfin Eel, Anguilla reinhardtii Steindachner 1867

References

Allen, G.R. 1989. Freshwater Fishes of Australia. T.F.H. Publications.

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

Aoyama, J., Mochioka, N., Otake, T., Ishikawa, S., Kawakami, Y., Castle, P. & Tsukamoto, K. 1999. Distribution and dispersal of anguillid leptocephali in the western Pacific Ocean revealed by molecular analysis. Marine Ecology Progress Series 188: 193-200.

Beumer, J.P. 1979. Feeding and movement of Anguilla australis and A. reinhardtii in Macleods Morass, Victoria, Australia. Journal of Fish Biology 14: 573-592.

Beumer, J.P. 1983). Eels. Victorian Naturist 100: 168-171.

Beumer, J.P. 1996. Freshwater eels. pp. 39-43 in McDowall, R.M. (ed.) Freshwater Fishes of South-eastern Australia. Reed: Sydney, Australia.

Beumer, J. & Sloane, R. 1990. Distribution and abundance of glass-eels Anguilla spp. in east Australian waters. International Revue gesamten Hydrobiologie 75(6): 721-736.

Castle, P. H. J. 1963. Anguillid leptocephali in the Southwest Pacific. Zoology Publications from Victoria University of Wellington 33: 1-14.

Kailola, P.J., Williams, M.J., Stewart, P.C., Reichelt, R.E., McNee, A. & Grieve, C. 1993. Australian Fisheries Resources. Bureau of Resource Sciences, Department of Primary Industries and Energy, and the Fisheries Research and Development Corporation: Canberra, Australia.

Kuroki, M., Aoyama, J., Miller, M.J., Watanabe, S., Shinoda, A., Jellyman, D.J., Feunteun, E. & Tsukamoto, K. 2008. Distribution and early life history characteristics of anguillid leptocephali in the western South Pacific. Marine and Freshwater Research 59: 1035-1047.

Langdon, S.A. & Collins, A.L. 2000. Quantification of the maximal swimming performance of Australasian glass eels, Anguilla australis and Anguilla reinhardtii, using a hydraulic flume swimming chamber. New Zealand Journal of Marine and Freshwater Research 34(4): 629-636.

McDowall, R.M., Struthers, C.D. & Stewart , A.L.2015. 37 Family Anguillidae. pp. 220-223 in Roberts, C.D., Stewart, A.L. & Struthers, C.D. (eds). The Fishes of New Zealand. Wellington : Te Papa Press Vol. 2 pp. 1-576.

Merrick, J.R. & Schmida, G.E. 1984. Australian Freshwater Fishes. Biology and Management. John R. Merrick.

Park, A. 1986. Incredible Voyagers. Australian Geographic. January-March 1(1): 24-33.

Pease, B.C. (ed.) 2004. Description of the biology and an assessment of the fishery for adult longfinned eels in NSW. Final Report to Fisheries Research and Development Corporation. Project No. 1998/127. NSW Department of Primary Industries - Fisheries Final Report Series No. 69. 167pp.

Pease, B.C., Reynolds, D.P. & Walsh, C.T. 2003. Validation of otolith age determination in Australian longfinned river eels, Anguilla reinhardtii. Marine and Freshwater Research 54: 995-1004.

Pike, C., Crook, V. & Gollock, M. 2019. Anguilla reinhardtii (errata version published in 2019). The IUCN Red List of Threatened Species 2019: e.T196303A154801946. https://dx.doi.org/10.2305/IUCN.UK.2019-2.RLTS.T196303A154801946.en. Downloaded on 27 August 2021.

Pusey, B.J., Burrows, D.W., Kennard, M.J., Perna, C.N., Unmack, P.J., Allsop, Q. & Hammer, M.P. 2017. Freshwater fishes of northern Australia. Zootaxa 4253(1): 1-104. https://doi.org/10.11646/zootaxa.4253.1.1

Pusey, B.J., Kennard, M.J. & Arthington, A.H. 2004. Freshwater Fishes of North-Eastern Australia. CSIRO Publishing, Collingwood, Victoria. 684 pp.

Roughley, T.C. 1955. Fish and Fisheries of Australia. Angus and Robertson: Sydney, Australia.

Shen, K.N. & Tzeng, W.N. 2007. Population genetic structure of the year-round spawning tropical eel, Anguilla reinhardtii. Zoological Studies 46(4): 441-453.

Shiao, J.C., Tzeng, W-N., Collins, A. & Iizuka, Y. 2001. Comparison of early life history of Anguilla reinhardtii and A. australis by otolith growth increment. Journal of Taiwan Fisheries Research 9: 199-208.

Shiao, J.-C., Tzeng, W.N., Collins, A. & Iizuka, Y. 2002. Role of marine larval duration and growth rate of glass eels in determining the distribution of Anguilla reinhardtii and A. australis on Australian eastern coasts. Marine and Freshwater Research 53: 687-695.

Silberschneider, V. 2005. Recruitment and age dynamics of Anguilla australisand A. reinhardtii glass eels in the estuaries of New South Wales. PhD thesis, University of Technology Sydney.

Silberschneider, V., Pease, B.C. & Booth, D.J. 2004. Estuarine habitat preferences of Anguilla australis and A. reinhardtii glass eels as inferred from laboratory experiments. Environmental Biology of Fishes 71: 395-402.

Sloane, R.D. 1984. Distribution, abundance, growth and food of freshwater eels (Anguilla spp.) in the Douglas River, Tasmania. Australian Journal of Marine and Freshwater Research 35(3): 325-339.

Sloane, R.D. 1984. Distribution and abundance of freshwater eels (Anguilla spp.) in Tasmania. Australian Journal of Marine and Freshwater Research 35: 463-470.

Smith, D.G. 1999 Anguillidae. Freshwater eels. pp. 1630-1636 in Carpenter, K.E. & Niem, V.H. (eds.) FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Vol. 3. Batoid fishes, chimaeras and bony fishes part 1 (Elopidae to Linophrynidae). FAO, Rome.

Tsukamoto, K. 2006. Spawning of eels near a Seamount. Nature 439: 929.

Walsh, C.T., Pease, B.C. & Booth, D.J. 2003. Sexual dimorphism and gonadal development of the Australian longfinned river eel. Journal of Fish Biology 63: 137-152.

Walsh, C.T., Pease, B.C. & Booth, D.J. 2004. Variation in the sex ratio, size and age of Australian longfinned river eels, Anguilla reinhardtii, within and among coastal catchments of south-eastern Australia. Journal of Fish Biology 64: 1297-1312.

Walsh, C.T., Pease, B.C. and Booth, D.J. 2006. Variability in growth of longfinned eels among coastal catchments of south-eastern Australia. Journal of Fish Biology 68: 1693-1706.

Watanabe, S., Miller, M.J., Aoyama, J. & Tsukamoto, K. 2011. Analysis of vertebral counts of the tropical anguillids, Anguilla megastoma, A. obscura, and A. reinhardtii, in the western South Pacific in relation to their possible population structure and phylogeny. Environmental Biology of Fishes 91: 353-360.