Cylindrospermopsis racihorskiiin Three Central Florida Lakes: Population Dynamics, Controls, and Management Implications

Cylindrospermopsis racihorskii is a potentially toxic cyanobacterium that has begun appearing, or alternatively, increasing, and has come to dominate some Florida water bodies. C. racihorskii began exponentially increasing in Lake Jesup, Florida around 1997. As a result, the phytoplankton community in the lake has declined in terms of species richness and diversity. Compared to other lakes in the region this species is still maintaining relatively dynamic population cycles in the lake. Lake stage appears to affect C. racihorskii differently than the aggregate phytoplankton community in Lake Jesup. Correlation analysis suggests that magnesium limitation, among other factors, may be an important factor influencing C. racihorskii growth in Lake Jesup, but appears absent in Lake Apopka and Lake Griffin. Finally, increases in C. racihorskii are associated with increases in phytoplankton biomass yield per unit phosphorus, having important implications for lake management and restoration.