Angullia rostrata (Lesueur, 1817)
member of the Eel Family (Anguillidae)
Photo by Garold W. Sneegas
Photo by Konrad P. Schmidt
St. Croix River, Chisago County, Minnesota July 1977
In a Name?
Anguilla (ann-gwill´-ah) means "eel"
Do They Live?
American eels used to be much more common in Minnesota then they are today. Today American eels are found mostly in the lower Mississippi River and its larger tributaries, such as the St. Croix and Minnesota rivers. Occasionally they are found in Lake Superior.
To reach Minnesota, American eels have to swim all the way up the Mississippi River from the Gulf of Mexico or all the way through the St. Lawrence Seaway and Great Lakes to reach Lake Superior. Only the females make the long swim to Minnesota (see reproduction below).
When not migrating, female American eels live in medium to large streams and lakes with muddy bottoms and quiet waters. They are most active at night. So, during the day they are found hiding in the mud or under objects such as rocks and logs at the bottom of the lake or river.
Big Do They Get?
We do not know exactly how long American eels live, but females spend 10-20 years before they become mature and return to the oceans. They die after breeding once.
"Cool Fact": American eels may live longer than most Minnesota species. One American eel lived in captivity for 88 years.
Do They Eat?
American eels do most of their feeding at night and are exclusively meat eaters. They feed on almost anything they encounter, including fish, frogs, crayfish, insects, snails, and even earthworms. They even have been known to feed on larval lampreys.
Do They Reproduce?
Once the female eel has reached maturity (after 10-20 years in the freshwater streams and lakes), she starts back down the main river (Mississippi River or St. Lawrence Seaway) towards the ocean to spawn. By the time she gets to the brackish (a little salty) water to meet up with the male eels, she has stored a lot of fat. The fat is high in oil and is used for the long journey ahead.
Males and females may swim for 2 to 3 months until the reach the spawning area, which is in the Sargasso Sea. They arrive at the spawning area in the late winter or early spring when water temperatures there are about 22°-25° C. The breeding extends into the summer months, and the adult American eels then die after spawning.
The female American eel may lay 10 to 20 million eggs during the spawning period. A newly hatched eel is a transparent, leaf-shaped larva called leptocephalus. These leptocephalus larvae drift in the ocean currents, which take them to the mouths of rivers off the coast of North America.
As the larvae drift, they slowly get bigger, and after one year are about 60 to 65 mm. At this size, they are small and transparent and are called glass eels. When they reach a coastal river, the males hang around in the estuaries, while the females swim far upriver. At this point they are about 65 to 90 mm long, have some coloring to them, and are called elvers.
"Cool Fact": The American eel is Minnesota's only
Catadromous fish. It lives most of its life in freshwater and migrates
to the ocean to spawn.
Permission is granted for the non-commercial educational or scientific use of the text and images on this Web document. Please credit the author or authors listed below.
Photographs by Konrad P. Schmidt
Text by Nicole Paulson & Jay T. Hatch in cooperation with
the Minnesota Department of Natural Resources' MinnAqua Aquatic Program
This page developed with funds from the
MinnAqua Program (Minnesota Department of Natural Resources, Division of Fisheries)
Sport Fish Restoration Program (Fish and Wildlife Service, US Department of the Interior)
Maintained by Jay T. Hatch
General College and James Ford Bell Museum of Natural History
University of Minnesota, Minneapolis/St. Paul
Last updated 23 October 2002