Coral reefs at Jobos Bay National Estuaries Research Reserve (JBNERR) have been in continuous degradation due to anthropogenic and natural inputs. A better understanding of reef health is needed to improve stakeholders' decisions and support proper management actions in the reserve. The FoRAM Index (FI) is a tool used to determine the water quality of reefs using foraminifers as bioindicators. Applying the FI as a seasonal long-term biomonitoring tool and identifying which physicochemical parameters, if any, are influencing the FI values are the priorities of this study. Four reefs; Cayo Caribe, Cayo Barcas, Cayo Pajaros and Cayo Morrillo, were sampled along transects in the front and back of each reef. Each transect is composed of 3 stations at different depths (5 m, 10 m, 15 m). At each station, sediment samples were collected for grain size and foraminiferal analysis. Water samples were obtained for nutrient analysis. Water quality parameters were measured through the water column.
Results/Conclusions
Limited variations in water quality and nutrient parameters were observed among reefs: pH (8.1-8.2), salinity (37.24-37.94 PSU), temperature (26.0-27.0 oC), dissolved oxygen (90-120 %), chlorophyll-a (0.22-1.2 µg/L), total suspended solids (0.575-1.41 µg/L), PO43- (0.04-1.0 µM), and NH4+(0.04-0.30 µM). These findings support the expected oligotrophic environmental conditions. The foraminiferal assemblage in the front to fore-reef settings are dominated by symbiont-bearing foraminifers (e.g., Amphistegina spp.). However, the inner portion of the reef is mainly dominated by heterotrophic species (e.g., Discorbis spp.). Predominance of sand-sized sediments in the front of the reef, and mud sediment composition in the back of the reef were found. Abraded specimens reflect the active hydrodynamic regime. Overall, FI values (5.6-10) indicated that water quality in the front to fore-reef of the four studied reefs are conducive to reef growth and recovery. The FI values are responding to total suspended solids (p-value = -0.63), chlorophyll-a (p-value = -0.64) and grain-size (p-value = -0.75) parameters. FI yields useful information about the current reef conditions and provides a rapid and cost-effective biomonitoring tool for JBNERR resource managers.