Altered freshwater inflows have affected circulation, salinity, and water quality patterns of
Florida Bay, in turn altering the structure and function of this estuary. Changes in water
quality and salinity and associated loss of dense turtle grass and other submerged aquatic
vegetation (SAV) in Florida Bay have created a condition in the bay where sediments and
nutrients have been regularly disturbed, frequently causing large and dense phytoplankton
blooms. These algal and cyanobacterial blooms in turn often cause further loss of more
recently established SAV, exacerbating the conditions causing the blooms. Chlorophyll a
(CHLA) was selected as an indicator of water quality because it is an indicator of phytoplankton
biomass, with concentrations reflecting the integrated effect of many of the water
quality factors that may be altered by restoration activities. Overall, we assessed the CHLA
indicator as being (1) relevant and reflecting the state of the Florida Bay ecosystem, (2)
sensitive to ecosystemdrivers (stressors, especially nutrient loading), (3) feasible to monitor,
and (4) scientifically defensible. Distinct zones within the bay were defined according to
statistical and consensual information. Threshold levels of CHLA for each zone were defined
using historical data and scientific consensus. A presentation template of condition of the
bay using these thresholds is shown as an example of an outreach product.