A long snake-like fish with an astonishing life cycle — born in the open Atlantic Sargasso Sea, drifting as larvae for a year before colonizing freshwater rivers, then returning to spawn and die.

Native status: Native; endangered

§ Quick facts

SizeAdult length 60–150 cm (24–60 in)
Weight0.6–7 kg (1.3–15 lb)
LifespanWild typically 15 years; oldest documented 88 (captive)
OrderAnguilliformes
FamilyAnguillidae

§ Encyclopedia

The American eel is a facultative catadromous eel found on the eastern coast of North America. Freshwater eels are fish belonging to the elopomorph superorder, a group of phylogenetically ancient teleosts. The American eel has a slender, supple, snake-like body that is covered with a mucus layer, which makes the eel appear to be naked and slimy despite the presence of minute scales. A long dorsal fin runs from the middle of the back and is continuous with a similar ventral fin. Pelvic fins are absent, and relatively small pectoral fins can be found near the midline, followed by the head and gill covers. Variations exist in coloration, from olive green, brown shading to greenish-yellow and light gray or white on the belly. Eels from clear water are often lighter than those from dark, tannic acid streams.

Source: Wikipedia — American eel Licensed under CC BY-SA 4.0

§ Identification

Field marks. Long snake-like fish with continuous dorsal-tail-anal fin. Olive-brown above, paler below.

Similar species. Lamprey (no jaws, no paired fins). Snakes (no fins, no gills).

Voice. Silent.

§ Diet & behavior

Diet. Carnivorous: small fish, crustaceans, insects.

Behavior. Catadromous — spends adulthood in fresh water, returns to spawn in Sargasso Sea. Reproduction never observed in wild. Population collapsed since 1990s.

§ Range

Eastern North America, Caribbean to Greenland

§ Habitat

Catadromous: lives in fresh water, spawns in Sargasso Sea

§ Threats

Dams blocking upstream migration, overharvest of juveniles ("glass eels") for Asian aquaculture, ocean current changes.

§ Conservation status

According to the IUCN Red List, the american eel is currently classified as Endangered.

§ What helps

Support dam removals and fish-ladder construction. Oppose unregulated glass-eel fishing. Donate to eel restoration.

Support our work More ways to help

§ Further reading

§ Sources cited

  • USFWS American Eel Recovery
  • NOAA Fisheries
  • Atlantic States Marine Fisheries Commission
  • IUCN Red List 2014