Diademaantillarum_SurveyData_Panama2014

Data collected by Joshua Hamilton, Jonathan Choi, and Nicole Zenes while affiliated with Princeton University in February 2014. For additional information, contact Jonathan Choi at jonathan.j.choi[at]duke.edu. This document was created on 12 July 2018.We conducted our surveys in February 2014 at three reef sites near Bocas del Toro, Panama (9.33° N, 82.25° W): Coco Key, a backreef site dominated by scleractinian corals and sponges; Coral Key, a backreef site primarily dominated by gorgonian corals and <i>Millepora</i>, and Salt Creek, a forereef site characterized by scleractinian coral dominance including large stands of Acropora. The two backreef sites were characterized by lower wave-action relative to Salt Creek. <i>D. antillarum</i> individuals were present at all sites, despite not sampling <i>D. antillarum</i> in our quadrats at all sites.We placed 30 m line transects on to the reef at random by determining a clock-face direction with the aid of a wristwatch and then placing the transect in the direction using our boat as a reference point. We placed 1 m² quadrats every 4 m on alternating sides of the transect line. We counted all <i>Echinometra viridis, E. lucunter</i> (binned as <i>Echinometra spp.</i> for analysis), and <i>D. antillarum</i> individuals within the quadrat. We estimated percent coral, algal, and bare substrate cover by partitioning the quadrat into 100 equal-sized squares with twine and recording the dominant form of substrate within each square. We stratified algal cover into broad functional groups: fleshy macroalgae (e.g. <i>Dictyota spp., Cladophora spp.,</i> etc.), calcareous algae (e.g. <i>Halimeda spp. &amp; Galaxaura spp</i>.), and encrusting coralline algae (e.g. <i>Porolithon spp</i>.). We took the average of percent coral and algal cover estimates of two independent observers in order to minimize personal bias.