Fish
American Eel
Anguilla rostrata · also called American eels
An eel that has spent thirty quiet years growing in a single freshwater pond suddenly changes shape, turns toward the sea, and begins a one-way journey across the entire Atlantic Ocean to a breeding ground it has never seen.
Overview
The American eel, Anguilla rostrata, is a long-lived fish native to freshwater rivers, lakes, and coastal wetlands along the Atlantic coast of North America, with every adult ultimately migrating to the Sargasso Sea to spawn. Its life cycle running in reverse of a salmon’s, land-crossing juveniles, and single, final ocean migration make it one of the more genuinely remarkable fish in North American waters.
A journey undertaken only once
After decades spent quietly growing in fresh water, an American eel makes a single, irreversible trip to the middle of the Atlantic Ocean to breed, a journey so demanding that no eel ever survives to make it twice.
Status
Endangered — populations have declined significantly, with dams and river barriers blocking the migration the species depends on to reproduce.
American Eel: common questions
Where does the American eel breed?
Every American eel migrates to the Sargasso Sea in the western Atlantic Ocean to spawn, the only known breeding location for the entire species, after which the adults die, having completed the single reproductive journey of their lives.
How is the American eel's life cycle different from a salmon's?
The American eel does the reverse of a salmon, spending most of its life growing in fresh water before making one final migration out to the ocean to spawn, while salmon are born in fresh water, grow at sea, and return to fresh water to breed.
Can an American eel really travel over land?
Yes, a young American eel can wriggle short distances across damp grass or mud, a remarkable ability that lets it reach isolated ponds and wetlands with no direct water connection to a river, expanding the habitat available to the species considerably.
Why is the American eel considered endangered?
Populations have declined significantly across much of the species' range, and dams and other river barriers that block migration between fresh water and the ocean are considered a major ongoing threat, since the American eel depends on completing that journey at least once to reproduce.