American eel

Anguilla rostrata

Order: Anguilliformes

Family: Anguillidae

Genus: Anguilla

The American eel is a long, snake-like fish with a smooth, scaleless appearance and a slimy, mucous-covered skin that helps reduce friction in water. Colour ranges from olive-green to brown on the back, with a lighter belly. It has small pectoral fins, a continuous dorsal and anal fin, and no pelvic fins. Eels undergo dramatic changes in appearance and physiology as they transition between freshwater and saltwater life stages.

Conservation Status: IUCN

Distribution

Found along the Atlantic coast of North and Central America and throughout inland waters connected to the Atlantic Ocean. In Canada, populations exist in Ontario, Quebec, and the Maritime provinces.

Habitat

Lives in freshwater, brackish, and coastal marine environments during most of its life but migrates to the Sargasso Sea (in the western Atlantic Ocean) to spawn—a journey of thousands of kilometres.

Diet

Carnivorous, feeding on aquatic insects, crustaceans, worms, fish, and other small aquatic organisms. Eels are mostly nocturnal hunters.

Reproduction

American eels are catadromous—they live in freshwater or brackish environments but migrate to the ocean to spawn. All individuals make a one-time migration to the Sargasso Sea to breed and then die. Eggs hatch into tiny, leaf-shaped larvae called leptocephali, which drift on ocean currents toward North America before transforming into juveniles (elvers) and migrating into rivers.