9-11 a.m. at Hickory Bluff Preserve, 598 Guise Road, Osteen. Wade in the waters of the St. Johns River. Use dip nets and seine nets to study the aquatic life living in this freshwater, riverine ecosystem. All ages are welcome; children must be accompanied by an adult. Participants must wear closed-toe shoes that can get wet. Free. Registration is mandatory; visit Green Volusia’s Eventbrite page at http://www.bit.ly/green-volusia. Contact Tommy Nordmann at tnordmann@volusia.org or 386-736-5927, ext. 12072.