Earlier this year, Al, Friends of the Upper Mississippi member and Gretchen were at Trempealeau National Wildlife Refuge with the Winona Oaks student group doing an activity with aquatic invertebrates we found there, including dragonfly, mayfly, and caddisfly larvae, and leeches, flatworms, blood worms, and small aquatic snails. Send us a message if you would like us to do a similar program for your group. Photo: Students peer into trays of invertebrates, Gretchen Newberry, USFWS.