The status and trends of the coral reefs around Saba, Dutch Caribbean, 2016

Coral reefs are of great value for millions of people, but at the same time they are facing a lot of threats of which almost all come down to human impacts. 70% of today’s reefs are rated as being threatened. Therefore, coral reefs are in the need for sustainable management based on scientific knowledge about reef threats & health. For the Caribbean island Saba, this is no exception. There is not yet extensive information available about the coral reefs around it and for that this research is conducted. Data is collected about density and biomass for key commercial and key herbivorous species according to the Global Coral Reef Monitoring Network. Data will be compared between current fished and unfished areas, and between 2015 and 2016. The same methods and materials are used in 2016 as in 2015 to make a reliable comparison. Data was collected using a Divers Operated stereo Video (DOV) and the images were analyzed in the program Event Measure. The statistical analyses were done using IBM SPSS and all data was tested for normality and homogeneity. GLM-tests, t-tests and Pearson’s tests were conducted. Also a Reef Health Index was made per site, per zonation (fished/unfished) and in total. It can be concluded that there is a higher biomass of key reef fishes in fished areas than in unfished areas. For density can be concluded that there was no difference in density, making the overall conclusion of difference between fished and unfished areas that there are more fish in fished areas, but that fish are bigger in the unfished areas. For the difference in biomass between 2015 and 2016 can be assumed that the data is not reliable, since the DOV was not calibrated and structurally measure fish too large. Therefor no conclusions can be made for that part. For density there is no significant difference between 2015 and 2016.