GRANITE FALLS, Minn. - An American eel - far, far away from its natural home in the North Atlantic Ocean - was found in a southwest Minnesota lake late last month.
Minnesota Department of Natural Resources fisheries workers conducting a lake survey on Cottonwood Lake about 16 miles southwest of Granite Falls captured a female, 37.4 inch American eel in their trapnet late last month.
American eel spawn in the Sargasso Sea in the north Atlantic Ocean. However, the American eel spends the majority of its life in freshwater habitat before returning to the Sargasso Sea to complete the life cycle.
According to the U.S. Fish and Wildlife Service, researchers have never witnessed eels spawning in the wild. They assume adult eels die after mating.
Larvae of this fish ride the currents randomly for hundreds or even thousands of miles before finding freshwater habitat. That makes this particular eel’s journey all the more impressive, having likely ridden ocean currents into the Gulf of Mexico and swimming upstream thousands of miles via the Mississippi River and the nearby Minnesota River.
“It’s not unheard of to find an American eel in the Mississippi or Minnesota River,” said DNR southern region fisheries manager Jack Lauer. “The interesting aspect to this particular eel is that it was caught in a lake a good distance from the river. It was well in excess of 30 river miles upstream from the confluence of the Yellow Medicine and Minnesota rivers.”
The eel on Cottonwood Lake was found during a routine standard survey. Those surveys are conducted every few years on a body of water to sample fish populations and the health of the fishery. That information is used to help manage a fishery.
This particular eel was a first for Spicer area assistant fisheries supervisor Brad Carlson.
“I’ve been conducting surveys since 1992 and have never seen an eel during a survey,” Carlson said. “At first I thought it was a bowfin because of the wavy dorsal fin. But I quickly realized that it was an American eel. It was a surprise because you don’t expect to find them in a shallow lake like Cottonwood - especially one so far from the Mississippi River.”
Carlson said he released the eel back in to Cottonwood Lake.
The lake-bound eel is rare, but not unprecedented. DNR fisheries records show that American eel commonly are found in the Mississippi and Minnesota rivers. However, this is only the second American eel that’s been discovered in a lake during a standard fisheries survey in the past 25 years. The other eel was found in Spring Lake, which has a direct connection to the Mississippi River.