olive to brown on the back, fading to greenish yellow on sides, gray or white underbody; snakelike body with small conical head and broad mouth; paired bluntly rounded pectoral fins; long, continuous dorsal, caudal, and anal fin
mainly in Mississippi River and its larger tributaries
fish, invertebrates, and terrestial organisms washed into the water
The American eel is mainly found in the Mississippi River and its larger tributary streams. However, recent fish collections in the Missouri from river miles 7l6 to 740 confirmed the presence of this species. In the Mississippi River, the American eel is currently listed as uncommon in the entire reach that borders Iowa. This fish is rather rare in collections, but it does not appear to be on the verge of extirpation.
Current status of the American eel in Iowa is uncertain, mostly because it is a difficult species to capture with conventional sampling methods. It is not, by any means, considered a threatened species. Construction of the impassable flood control dams on the Des Moines, Iowa and Chariton rivers has undoubtedly restricted the migration of eels in these drainages, but the impact on resident populations is unknown. Even though the eel is not abundant in its Iowa range, it does not appear to be on the decline over the last 20 to 30 years.
Color of the American eel varies considerably, usually from olive to brown on the back, fading to greenish yellow on the sides, and gray or whitish beneath. The body is long and slender, resembling a snake more than a fish. The head is small and conical with a broad mouth that contains numerous sharp teeth. The fins are peculiar to this fish with paired, bluntly rounded pectorals and a single continuous dorsal, caudal and anal fin.
The eel prefers fairly deep, mud-bottom waters, which probably accounts for the reason they are most often found in the larger rivers. Weight rarely exceeds a couple of pounds, but some individuals, especially if landlocked, may reach a maximum of 5 to 6 feet and weigh l0 to l5 pounds.
Eels, because of their snakelike movements, are able to navigate in extremely shallow marshy areas. They are largely nocturnal feeders consuming mainly fish, invertebrates and terrestrial organisms that are washed into the water. Eels are carnivores and, contrary to earlier thinking, seek living rather than dead organic matter.
The spawning life cycle of the American eel is endemic to this species. Eels are catadromous, which means they spawn in saltwater and mature in freshwater. The cycle begins with the female maturing in freshwater streams over a period lasting from 5 to 20 years. Upon maturity they migrate downstream to the sea in autumn. Females are joined by the males, which have remained in the estuaries, never growing much more than 2 feet in length. The suspected area of spawning for all freshwater eels is in the southwestern North Atlantic Ocean east of the Bahamas and southwest of Bermuda in a region often referred to as the Sargasso Sea.
After spawning, mature males and females have not been observed near spawning grounds and are presumed to die. Eggs of the eel have never been sampled in the ocean, but it has been estimated a single female may produce from 5 to 20 million eggs. It takes at least a year of travel for the transparent, leaf-like eel larvae to reach freshwater streams along the coast of North America. Larval eels are called leptocephalus larvae and move via oceanic currents. Upon reaching the coast, these larvae metamorphose into 2 l/2 inch long worm-like transparent "glass eels" and begin ascending coastal streams to their eventual home to mature.
Fishing for eel is unimportant in Iowa, and most of those caught are taken incidental to other species. They are taken by commercial fishermen from the Mississippi, but the harvest each year is usually less than 2,000 pounds. The flesh of eel, while very rich, is said to be delicious. It is sometimes prepared by pan-frying but is more often smoked, pickled or jellied. Smoked eel is by far the most accepted and is considered a delicacy. There is little demand for eels in this section of the country.