RIVER FISH · River-to-ocean migrant
American eel
Anguilla rostrata
A snake-shaped catadromous fish that grows in rivers and estuaries but migrates to the Sargasso Sea to reproduce.
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Meet the fish
- Habitat
- Rivers, estuaries and some inland lakes; during the day eels often shelter near shore among plants, snags and other cover.
- On the menu
- Nocturnal feeding on crustaceans, insects, worms and fish.
- Size context
- USFWS reports females can reach about 4 feet while males are much smaller, reaching roughly 1.5 feet.
- Range & local context
- Atlantic and Gulf drainages from northern South America through the United States and Canada, including the Mississippi system and some inland lakes.
Living with the river
Water & habitat
Connectivity can matter more than any one gauge value. Dams and barriers can interrupt a life cycle that links inland rivers to the Atlantic Ocean.
Seasonal life
Mature eels leave freshwater and estuarine habitats for a long migration to the Sargasso Sea, where spawning occurs.
Before you go
Eel rules and conservation concerns vary by jurisdiction. Check current harvest regulations and fish-passage conditions locally.
Use the linked agencies and the relevant river guide for current regulations, closures and consumption advisories. A species profile is not a fishing license or a statement that harvest is allowed.
Editorial review: . Regional size examples are labeled; maximum lengths are not typical sizes.
More river fish
Keep exploring species connected to the same river-guide network.