Overview of the mesophotic coral ecosystems around Sesoko Island, Okinawa, Japan

Coral reef ecosystems extend beyond the standard SCUBA diving depth. These ecosystems found between approximately 30 and over 150 m are referred to as mesophotic coral ecosystems (MCEs). Mesophotic coral communities have already been reported from Okinawa over 50 years ago. However, since then little additional knowledge has been obtained on the distribution and diversity of mesophotic corals in the region. Here, we provide an overview of the coral communities observed at selected sites in the region around Sesoko Island. Using photo-quadrats, we surveyed coral communities and specifically the contribution of the dominant coral genera to the total coral cover between different sites at depths ranging from 30 to 80 m. We found that deep coral communities around Sesoko Island hold a high potential biodiversity and need to be taken into account into coastal management plans.