Freshwater eels

Freshwater eels are long, snake-shaped fish that spend most of their lives in rivers and lakes. In this app the group includes the European eel, American Eel, and Australian Long-finned Eel.

Look for the snake-like body and the single long fin running around the tail, which separates them from true snakes and most other fish. Members are hard to tell apart underwater; size is the main clue, since females grow much larger than males.

These eels have long, tube-like bodies and a large, pointed head. Their back, tail, and belly fins join into one long fringe around the rear of the body, and they have no pelvic fins. The skin is brown, olive, or olive-yellow, often mottled, which helps them blend in with the river or lake floor.

Freshwater eels live in rivers, lakes, and estuaries in tropical and temperate waters around the world, though they are absent from the eastern Pacific and South Atlantic. They spend their adult lives in fresh water but return to the ocean to breed.

These eels hide under rocks, logs, and in mud at the bottom of the water during the day. They can change colour to match their surroundings, which helps them ambush prey and hide from predators.

Freshwater eels are carnivores. They hunt other animals, using their flexible bodies to move through complex spaces such as reefs and river bottoms.

Freshwater eels breed only once in their lives, then die. They travel from fresh water back to the ocean to spawn, and their eggs hatch into small, leaf-like larvae that drift on ocean currents, sometimes for thousands of miles, before growing into young eels.

harmless to humans

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  American Eel

  Anguilla rostrata

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  Australian Long-finned Eel

  Anguilla reinhardtii

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  European eel

  Anguilla anguilla

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  Marbled Eel

  Anguilla marmorata

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  New Zealand Longfin Eel

  Anguilla dieffenbachii

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  Short-finned Eel

  Anguilla australis