An interdisciplinary and multiagency study was undertaken to study harmful algal bloom (HAB) dynamics on the Caloosahatchee River, which drains to the west from Lake Okeechobee into the Gulf of Mexico. Algae and cyanobacteria play crucial roles in aquatic ecosystems, but under favorable environmental conditions certain taxa may experience population growth booms resulting in HABs. Four independent mesocosm experiments were conducted in September 2019, June 2020, September 2020, and February 2021 to capture natural temporal variability in water quality and phytoplankton assemblages. The experimental installation consisted of three floating metal cradles each containing four fiberglass chambers filled with native river water. The twelve [...]