RIPARIAN VEGETATION ALONG TRIBUTARIES TO ESTERO BAY, FLORIDA

We examined the riparian vegetation along the five main tributaries to Estero Bay, Lee County. Florida. Riparian vegetation serves as a non-motile integrator of salinity conditions over time, and may prove useful for detecting shifting salinity gradients associated with altered freshwater flow. An objective of this project was to refine our understanding of the freshwater/estuarine interface in the Estero Bay tributaries, using riparian vegetation as ecosystem indicators. We directly sampled 0.9 ha and documented 126 plant species or genera. Variation in riparian vegetation communities among tributaries and position along tributaries seemed to be related to degree and period of land use change. We examined changes in riparian vegetation through analysis of aerial photography from 1966, 1981 and 2002. Historic patterns of shifts in riparian vegetation communities of Estero Bay tributaries are dominated by a loss of upland vegetation and an increase in human modified landscapes. A suite of freshwater and saltwater indicator species proved useful in distinguishing among tributaries, and particularly between positions along the tributaries. These indicator groups may be utilized for: documenting the ecological effects of alterations in freshwater flow; establishing restoration performance measures; and establishing Minimum Flows and Levels for tidally influenced streams of SW Florida.