American Eel

Anguilla rostrata

The American eel is a smooth and snake-like fish. It is greenish or yellowish-brown above and whitish on the belly. Adults have:

• A rounded tail.
• A continuous fin stretching around the tail from the back to the belly.
• Tiny, elliptical scales embedded in the skin.
• Females usually grow to about 3 to 5 feet long, while males are shorter, usually growing to about 2 feet long.

Where does the American eel live?

American eels are found throughout the Bay watershed, from creeks and ponds to the deep, swift channels of the Bay. Adults usually live in fresh to brackish rivers and streams, but some remain in the Bay's shallow, nearshore waters.

What does the American eel eat?

American eels feed at night on a variety of prey, including:

• Worms
• Small fishes
• Macoma clams and other mollusks, whose siphons sticking out of the sediment look like worms
• Crustaceans, such as soft-shelled crabs

What is the life cycle of the American eel?

American eels are the only catadromous fish in the Bay.

• In October, sexually mature eels swim down streams and rivers, out of the Bay and to the Sargasso Sea, an area of the Atlantic Ocean west of the Bahamas. In January, the eels spawn there, and then die.
• Tiny eel larvae drift in the ocean for about nine to 12 months, during which time they transform from larvae to the “glass eel” stage. Ocean currents carry the transparent glass eels thousands of miles to the U.S. coast.
• Before entering the Bay, the glass eels become pigmented. These brown eels, called elvers, are only about 2.4 inches long. Some elvers stay in the Bay, but most continue to swim many miles up the Bay's rivers and streams to fresh water.
• After a few months the elvers transform into the adult “yellow eel” stage. There they remain for the majority of their lives, until they reach sexual maturity and return to the Sargasso Sea to spawn and die.

Other facts about the American eel:

• During their migration up the Bay's rivers and streams, American eels overcome multiple obstacles to reach their destination. They can slide over rocks, dams, wet grass and other seemingly impassable blockages.
• Eels are active at night. During the day they will often hide under a rock or bury themselves in bottom sediments.
• Usually lives for at least five years; some American eels can reach 15 to 20 years old or more.
• Many people think that eels are snakes, but they really are true fishes.
• While most Americans may think eels are slimy and gross, in Asia and Europe they are considered a delicacy. Most of the American eels caught in the Bay region are exported overseas.