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Additional authors: Debbie Pouder, UF SFRC, Tropical Aquaculture Laboratory; William Sharp, FWC Fish and Wildlife Research Institute; Gabriel Delgado, FWC Fish and Wildlife Research Institute; Nicole Stacy,UF College of Veterinary Medicine; Tom Waltzek, UF College of Veterinary Medicine; Greg Beck, University of Massachusetts (Boston); Roxanna Smolowitz, Roger Williams University. The long-spined sea urchin, Diadema antillarum, is a keystone species in coral reef ecosystems throughout the Caribbean basin. In 1983-1984, a wide scale mortality event resulted in the loss of more than 90% of the D. antillarum populations throughout the region. The cause of this die-off is believed to have been an infectious agent, but a specific etiology was never determined. The loss of these important grazers has been tied to declines in coral reef habitat and environmental health, and although changes to the coral reef ecosystems are complex, the current hypothesis is that recovery of D. antillarum is necessary for their successful restoration. The State of Florida has invested substantially in coral reef restoration efforts in the Florida Keys. Concurrent with efforts to culture D. antillarum for future stock enhancement, the State determined that health assessment would be required before these cultured organisms could be released in Florida waters. To develop meaningful diagnostic protocols for this species, it was necessary to determine baseline health data, to collect reference tissue samples, and to assess the “normal background flora” of D. antillarum. Seasonal sampling was conducted in March, April, and September 2015 and a total of 189 D. antillarum (46 from the Lower, 71 from the Middle, and 72 from the Upper Keys) were necropsied using health assessment protocols developed during this project. Physical examination, including a behavioral assessment, was useful in recognizing potentially unhealthy animals. Coelomic fluid was used for bacterial screening and fecal examination provided for an assessment of gastrointestinal flora which routinely included several commensal ciliates. Most D. antillarum examined appeared to be in good physical condition, based on examination criteria. A few, however, were less responsive to behavioral stimulation or had visible external lesions. Findings from these few individuals will be compared to the broader group. |