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SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It Again OceanEye to eye with Britain's hidden sharks at SharkAdemy - Oceanographic RiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at all OceanShedd Aquarium Sends Shark Eggs to Bolster Wild Populations SpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for Conservation OceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray Area SpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow Reductions FisheriesAdams River Salmon Run in Thompson-Nicola IndiaHilsa production dropped 26% in five years, fisheries minister tells parliament SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It Again OceanEye to eye with Britain's hidden sharks at SharkAdemy - Oceanographic RiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at all OceanShedd Aquarium Sends Shark Eggs to Bolster Wild Populations SpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for Conservation OceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray Area SpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow Reductions FisheriesAdams River Salmon Run in Thompson-Nicola IndiaHilsa production dropped 26% in five years, fisheries minister tells parliament

EveryFish

Eels

Freshwater and moray eels, conger and the swamp eels. 12 fish on EveryFish so far.

True eels, the order Anguilliformes, are long, snake-shaped fish with no pelvic fins and, in most species, a single long fin running around the back, tail and belly. There are about 900 species, from the freshwater eels of rivers worldwide to moray eels of reefs, conger eels and burrowing snake eels. Swamp eels and the electric eel look similar but belong to other groups.

The eel's long journey

Freshwater eels live for years in rivers and lakes, then swim to the sea to spawn and die. European and American eels travel to the Sargasso Sea; the Japanese eel spawns west of the Mariana Islands. Their transparent, leaf-shaped larvae drift back on ocean currents and turn into glass eels near the coast. India has several freshwater eels, including the mottled eel. No one has yet bred freshwater eels in large numbers on farms, so eel farming depends on catching wild glass eels.

Eels in trouble

Eel catches have fallen sharply since the 1980s. The European eel is Critically Endangered, and the Japanese and American eels are also threatened, with dams, overfishing of glass eels, pollution and changes in the ocean all blamed. The European eel is listed on CITES Appendix II, and the European Union bans its export, but illegal smuggling of glass eels to Asian farms continues. Unagi, grilled eel, is a summer dish in Japan.

Famous eel fish

Giant morayA large moray eel of Indo-Pacific reefs

Asian swamp eelNot a true eel, a fish of paddies and ponds

Still to be written: European eel, American eel, Japanese eel, Anguilla bengalensis, European conger.

Further reading

Photo credits on this page

The small pictures above come from Wikimedia Commons under free licences. Some are cropped to fit.

Giant moray: Nhobgood Nick Hobgood, CC BY-SA 3.0, source
Asian swamp eel: Leo G. Nico, USGS, Gainesville, FL, Public domain, source
Peacock eel: Unknown author, Public domain, source

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