The Anguillidae family contains 15 species, two of which, Long-finned Eel Anguilla reinhardtii and Short-finned Eel A. australis, are found in Australia. Freshwater eels are long and muscular with a skin which is brown or yellow in young fish and gradually turns mottled on the Long-finned Eel or darkish olive on the Short-finned Eel as the fish matures. Adults preparing for their seaward migration gradually turn silver. Long-finned Eels are the more tropical species, while Short-finned Eels tend to live in more temperate areas, although both can be found up and down the east coast of Australia (including Tasmania and South Australia) and as far as the Bass Strait Islands, New Zealand, Lord Howe Island and New Caledonia.
While the two eels’ territories overlap, they are easy to tell apart. The top (dorsal) and bottom (anal) fins of the Short-finned Eel begin at about the same point on the body, and a fair way back. The dorsal fin of the Long-finned Eel, on the other hand, starts well in front of the anal fin, and this species has a much more spotted and blotched pattern across its body. It prefers flowing rivers and creeks more than the calm ponds and lakes the Short-finned tends to inhabit.
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