Multiple Cumulative Effects on Coral Reefs of the Northwestern Cuban Region

Abstract

In recent decades, there has been an accelerated deteriora- tion of coral reefs due to the synergistic effect of natural and anthropogenic stressors. Thus, the objective of this chapter is to evaluate the cumulative effects produced by multiple stressors that impact coral reefs of the northwest- ern region of Cuba. To this end, ecological indicators were estimated at community level (i.e., coral species; density of corals, gorgonians, sponges, and fish) and population level (i.e., sizes and health of Siderastrea siderea and Montastraea cavernosa). The results show structural changes in communities driven by existing anthropogenic impacts, which vary in intensity (low, medium, and high impact area) along the northwestern coast of Cuba, decreasing from the east-west. In addition, these impacts and changes decrease in the east-west direction. The eco- logical indicators show differences between the sites with different levels of impact. Corals and gorgonians were more abundant in sites with medium impact, while sponges were more abundant in the area with high impact. The density of herbivorous fish was higher in sites with low and high impact and lower in sites with medium impact. The indicators assessing the health of the corals better reflect the effect of impacts such as the increase in sea surface temperature and extreme meteorological events. In sites where eutrophication and sedimentation prevail, bleaching processes are not as critical.