Loggerhead sea turtles (Caretta caretta) nest in numerous substrate and beach
types within the Ten Thousand Islands (TTl) of southwest Florida. Nesting beach
selection was analyzed on 12 islands within this archipelago. Numerous physical
characteristics were recorded to identify the relatedness of these variables and determine
their importance for nesting beach selection in C. caretta. These variables were chosen
after evaluating the islands, conducting literature searches and soliciting personal
communications. Along transects, data were collected, on the following: height of
canopy, beach width, overall slope (beach slope and slope of offshore approach) and sand
samples analyzed for pH, percentage of water, percentage of organic content, percentage
of carbonate and particle size (8 size classes). Data on ordinal aspect of beaches and
beach length were also recorded and included in the analysis. All of the variables were
analyzed by tree regression, incorporating the nesting data into the analysis. In the TTl,
loggerheads appear to prefer wider beaches (p< 0.001; R2
= 0.56) that inherently have less
slope, and secondarily, wider beaches that have low amounts of carbonate (p< O.00 1). In
addition, C. caretta favors nest sites within or in close proximity to the supra-littoral
vegetation zone of beaches in the TTl (p< 0.001). (86 page document
