NCCOS-supported research recently published in Coral Reefs suggests coastal development negatively impacts mesophotic coral ecosystems, which were previously considered less likely to be affected by anthropogenic activities due to their greater depths. The project assessed the vulnerability of light-dependent mesophotic coral ecosystems (MCEs) off the south coast of Puerto Rico to anthropogenic impacts. Results showed that MCEs located off Ponce, an impacted area, had 16 times greater rates of sedimentation in comparison to MCEs off La Parguera, a less impacted area.
The narrow insular shelf off Ponce, Puerto Rico’s second most populated municipality, makes deep-water dredge disposal for the commercial port and sewage outfall financially feasible solutions. This research documented that the maximum depth of mesophotic corals increased with distance from Ponce and the deep-water dredge disposal sites and sewage outfall. MCEs are light-dependent extensions of shallow coral reef ecosystems, host a unique and biodiverse species assemblage, and serve as a refuge for large overfished species. Therefore, it is important to consider MCEs when permitting activities that may impact water clarity and light penetration.
This work is part of NCCOS’s Deep Coral Reef Ecosystem Studies program which is led by the University of Puerto Rico and the Caribbean Coral Reef Institute. Designed to improve the understanding of MCEs off La Parguera, PR, the program goals include: characterizing Deep Coral Reef Ecosystem community composition and structure, determining their potential connectivity, and assessing their vulnerability to anthropogenic stresses.
For more information, contact Kimberly Puglise.