Shedd experts in riverShedd’s Great Lakes conservation biologists are the real deal—they do incredible work to advance aquatic science in the Great Lakes. But you don’t need a Ph.D. to understand the importance of their work, or to appreciate the fun of getting into a river with a pair of waders to survey Great Lakes fishes. Last week, Shedd’s Great Lakes experts Dr. Phil Willink and Dr. Solomon David led a small group to Custer Park, IL, where we waded along the banks of the slow-moving Kankakee River in search of a small glass-clear fish. They’re called the western sand darter (Ammocrypta clara), and although they’re prevalent in the Mississippi River basin, the sand darter has not been seen in this part of the Kankakee since the 1980s. As such, it’s a state-listed endangered species.

Optimistic from the outset, we tromped down to the river avoiding as best we could the broad leaves of poison ivy. Clad in rubber waders with fish probe and seine in hand, we waded upstream, stopping to survey anywhere that looked like promising fish habitat – often plant covered islands or submerged tree branches and roots. We immediately saw green sunfish, rock bass and several species of minnows and shiners. But no sign of the sand darter.

Much of Kankakee in this area has a silty and rocky bottom, and some areas along the bank were so thick with mud that our waders made sucking sounds as we maneuvered through branches. As its name suggests, the sand darter prefers sandy bottoms. In fact, this slender fish is adapted to bury itself in the sand, leaving only its eyes and snout protruding from its hidden den. Lacking this preferred habitat didn’t help our search, and by the end of the day we still had no evidence of the sand darter in this part of the Kankakee. However, we did see 25 individual species of fish, including two uncommon species of catfish and another state-endangered fish called the pallid shiner (Hybopsis amnis). According to our experts, this level of biological diversity tells us that the river is in good condition. So, although the search for the sand darter continues, seeing the number of fishes we did made the trip a big success. Not a bad day in the field for Shedd’s Great Lakes conservation scientists!

Reid Bogert, Great Lakes and sustainability