The Least Brook Lamprey is an extremely unlikely-looking fish to encounter in the spring-fed creeks of our state. All lampreys have a long eel-like body and no scales. They have segments of muscles that are visible along their body and a jawless mouth.
As with all lamprey species, the Least Brook Lamprey spends the majority of its life as a worm-like larva. Larvae live burrowed in the sand at the bottom of a waterway for 3–7 years, feeding on microscopic plant and animal life.
This fish is found in clear brooks with fast flowing water and either a sand or gravel bottom. Prior to laying eggs, adults construct small nests by picking up pebbles with their oral disk and moving them to form the rims of shallow depressions.
Adult Least Brook Lamprey cannot eat. Since they have a nonfunctional intestine, they only live for four to six months. Instead of eating, they spend all their time building nests, finding mates and laying eggs so the next generation will be there to carry on.
Lampreys are a diverse and ancient line of creatures tracing back to over 300 million years ago. Of the many fish species native to Ohio, this is one of the least known, but most interesting.