Does nutrient pollution affect the prevalence of dark spots disease in corals on Bonaire, Dutch Caribbean?
Environmental changes and deterioration have increased coral disease outbreaks, creating a Caribbean hot spot of high disease prevalence and virulence. Dark spots disease (DSD) has an unknown causative agent, although it is suspected to be a result of a biotic pathogen. Variation with anthropogenic stressors and DSD has been limited in research; therefore, the purpose of this study was to determine if a correlation existed between DSD prevalence and nutrient enrichment, in the form of nitrogen concentration. It was hypothesized that DSD prevalence and nitrogen concentration would be highest at shallower depths and that there would be a positive correlation between DSD prevalence and nitrogen concentration. In Kralendijk, Bonaire, sites were surveyed for DSD to calculate the prevalence and water samples were collected to determine the concentration of nitrogen. The results indicated no significant effect of depth and site on DSD prevalence as well as no significant effect of depth on nitrogen concentration. There was a significant effect of site on nutrient concentration as indicated by the significantly higher nitrogen concentration. The pooled data illustrated a weak positive relationship and correlation between DSD prevalence and nitrogen concentration with insignificant results, but one site illustrated a moderately strong positive relationship and correlation with statistical significance. The significant results at that site suggest some correlation between DSD prevalence and nitrogen concentration which requires further investigation ex situ to establish a stronger correlation or possible causation.
This student research was retrieved from Physis: Journal of Marine Science XV (Spring 2014)19: 36-44 from CIEE Bonaire.