An Analysis of Pre and Post Hurricane Coral Reef Community Dynamics in the Biscayne National Park: A Before and After Study in which the "Before" is Really Known

Porter, James

This pre-proposal is on assessment, inventory and monitoring of coral reefs. Hurricanes damage coral, especially when the system is already sub optimal, like the waters of Biscayne National Park This proposal includes several predictions, images of research plans, methodology, and resumes of people involved (James Porter, Robert Cheney, Sarah Lewis, and Jennifer Icy Tougas).Hurricane Andrew was only the tip of the iceberg of coral reef problems in SouthFlorida. Prior to Hurricane Andrew, five of six coral reefs studied photogrametrically since1984 declined precipitously in percent live-coral cover and coral species diversity (Porter andMeier, 1992; see attached reprint). The loss varies between 4% and 10% per year for coralcover and between 13% and 33% for coral species diversity. All the reefs studied are inprotected areas (either in National Marine Sanctuaries or National Parks). The only pattern that emerges is an odd inverse correlation between reef decline and reef latitude: reefs in the Lower Keys are loosing coral faster than reefs in the Upper Keys. In fact, the only reef that grew during the survey was Ball Buoy Reef in the Biscayne National Park.We call our best (and at present only) testable hypothesis to explain this pattern of decline The Florida Bay Water Hypothesis. Briefly stated, it is as follows:Due to the diversion of freshwater from its historical flow patterns in South Florida,water in Florida Bay is of increasingly poor quality with respect to salinity, temperature,oxygen content, nutrient content, and turbidity. Based on hydrography, this water moves between the Florida Keys, under Hawk Channel (due to is hyper-salinity induced density),and out onto coral reefs on the Florida Reef Tract. Based on its suboptimal quality, this water causes increased coral mortality and decreased coral recruitment to reefs in its path.The correlation between coral mortality and latitude is therefore spurious, the causal link is not between mortality and latitude, but between coral mortality and the frequency and duration of contact with Florida Bay Water.