Looe Key is a coral reef in the lower Florida Keys and a national marine sanctuary. Nitrogen-rich effluent from Florida Key developments and runoff from agricultural areas in the northern Everglades have caused the waters off Looe Key to become increasingly eutrophic. The resulting reduction in water clarity and increased water column dissolved inorganic nitrogen (DIN) have caused significant increases in macroalgae and turf algae growth, phytoplankton blooms, and coral diseases. In addition to the effects of eutrophication, symptoms associated with climate change such as coral beaching and increased susceptibility to diseases (e.g., black-band, yellow band, and white-pox) are exacerbating the deteriorating conditions around the reef. The increase of macroalgae populations also has triggered a shift in fish community structure, from piscivorous species like snapper and grouper to herbivorous fish such as parrotfish and surgeonfish.
Expected increases in residential population growth and effects of climate change in the Florida Keys and South Florida, and the potential for increasing nitrogen input to the waters of Looe Key will increase stress on the corals. A better understanding of the combination of factors that create this stress is required (Bricker et al. 2007).
Reference:
Bricker, S., B. Longstaff, W. Dennison, A. Jones, K. Boicourt, C. Wicks, and J. Woerner. 2007. Effects of Nutrient Enrichment In the Nation’s Estuaries: A Decade of Change. NOAA Coastal Ocean Program Decision Analysis Series No. 26. National Oceanic and Atmospheric Administration, National Centers for Coastal Ocean Science, Silver Spring, MD. Accessed October 2016. https://yosemite.epa.gov/oa/EAB_Web_Docket.nsf/(Filings)/3BE82A42C7ED8C3585257B120059CB8A/$File/Opposition%20to%20Petition%20for%20Review%20–%20Ex.%2010%20Part1…23.53.pdf.