The American eel (Anguilla rostrate) is a state threatened species of freshwater eel, and the only freshwater eel found in North America. These eels are found in any Ohio stream and in Lake Erie, but their home range covers most of the eastern United States. They are most normally found in large rivers with continuous flow. The American eel is a nocturnal species. They tend to hide in deep pools during the day and feed on aquatic invertebrates and fish at night. They are a prey species to larger fish, like bass, reptiles, some mammals, and fish-eating birds.
Adults have a long, cylindrical snake-like body with a single dorsal fin running along their body. They have short, round pectoral fins on the side of their body and a mouth filled with very small teeth. These eels are very muscular and secrete a slime that creates a protective mucus layer around their body. Adult American eels can have a wide color range, most being brown with yellow on the sides. They will then turn a black and silver or bronze eel during their reproductive phase. Males can get about 18 inches long while females are larger, averaging about 36 inches.
The American eel is a catadromous species, meaning they spawn in saltwater but spend most of their lives in freshwater (Ohio DNR Division of Wildlife). Little is known about the spawning of the American eel, as no one has witnessed it. What we do know is that adult eels migrate downstream to the ocean by using what is thought to be the Earth’s magnetism and their homing abilities. These eels spawn only in the Sargasso Sea, a warm region of water located in the southeast of the Atlantic Ocean. These eels will spawn and then die. The females can lay up to about four million eggs, who, once hatched, are small transparent larvae who float on the ocean’s currents for about 12 months (The Nature Conservatory). The surviving eels will then migrate their way back towards North America and into freshwater. These baby eels will then travel upstream into rivers, estuaries, and bays, spending as much as 20 years in freshwater before beginning the life cycle over again.
The American eel populations have been on the decline. Dams and other human-made obstacles in the rivers have had the largest impact on their populations. These obstacles prevent the eel from migrating upstream or downstream, sometimes preventing populations from reaching the Sargasso Sea to spawn. These obstacles also cause habitat loss, putting stress on the eels from predators as they are a easy prey species (USFWS). American eels are also very susceptible to low water quality, meaning that habitat degradation has also negatively effected populations. These eels are harvested for food, and the overfishing of juveniles have added to the overall decline of this species. This makes it very important to conserve the American eel so these fish don’t become extinct. They are such a unique species, with their distinctive life cycle and that fact that they are the only freshwater eel in North America. American eels are a treasure to have in Ohio, so help protect their habitat so that future generations can enjoy them too.
References:
“American Eel.” Ohio DNR Division of Wildlife, ODNR Division of Wildlife, wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/american-eel.
“Information About the American Eel.” The Nature Conservancy, www.nature.org/newsfeatures/specialfeatures/animals/fish/american-eel.xml.
“American Eel Videos, Photos and Facts.” Arkive, www.arkive.org/american-eel/anguilla-rostrata/.
USFWS Northeast Region Division of External Affairs. “The American Eel.” National USFWS Website, www.fws.gov/northeast/americaneel/.
Images (In Order of Appearance):
Photo by Minnesota Department of Natural Resources
Photo by Cornell University
Photo by Melisa Beveridge