Nature Journaling Tip #21: The American Eel

One of the most amazing and mysterious animals with an ocean connection is the American eel. These snakelike fish spend most of their lives in rivers and estuaries and migrate to a particular area of the Atlantic Ocean called the Sargasso Sea, between Bermuda and the Bahamas, to spawn.

In their first year, tiny willow leaf-shaped eel larvae drift on ocean currents toward estuaries along the coast, where they transform into little "glass eels." Then they become pigmented "elvers" and migrate up many of the rivers along the Atlantic coast. Most of those that migrate are females; most males stay in the estuaries.

Some streams, such as the Delaware River, offer habitat for yellow eels far up into their headwaters if hydroelectric dams or other obstructions don't block their way. Females may reach three feet or more in length and live 30 years before becoming sexually mature silver eels. At this stage, male and female eels migrate back out into the open ocean and swim to the Sargasso Sea where they breed and die. Practically nothing is known about this part of their life cycle because no one has ever actually seen it happen.

Citizen scientists and marine biologists are working together on projects to understand American eel migration routes and patterns in an effort to manage populations and restore habitat along the Atlantic coast.

Mark Baldwin is the Director of Education at the Roger Tory Peterson Institute of Natural History (RTPI), a proud partner in National Environmental Education Week. Each year RTPI offers online workshops for educators interested in bringing nature journaling into the classroom. For more information visit www.rtpi.org.