TOPEKA (KSNT) — A group of Kansas wildlife biologists on the hunt for invasive species made a surprising discovery in April when they found a fish thousands of miles away from where it spawned.

Biologists with the Kansas Department of Wildlife and Park’s (KDWP) Aquatic Invasive Species Crew were conducting sampling operations on the Kansas River near Kaw Point in April when they came across a rarely seen native fish species. The fish in question is known as an American eel.

These fish are not often seen in Kansas’ waters, mostly due to the many dams that get in the way of their ability to move freely through U.S. streams and rivers. The last time the KDWP made note of the appearance of one of these eels was in 2015 when a Kansas angler caught one while fishing below the Bowersock dam near Lawrence, Kansas. At the time, this was the first confirmed sighting of an American eel in Kansas in a decade.

Despite their rarity in Kansas, the species is not considered endangered and the KDWP does keep a fishing record for the elusive eels. The current state record for American eel in Kansas was set June 23, 1987, by Ralph B. Westerman on the Kansas River. He landed an American eel weighing 4.44 pounds and measuring 35.25 inches in length while using a rod and reel.

American eels make an astounding 3,500-mile migration from their spawn point in the Sargasso Sea, located in the Atlantic Ocean, to the rivers and streams of North America where they live for around 10-25 years before returning home to reproduce. They are also the only species of freshwater eel found on the continent, according to U.S. Fish and Wildlife Service.