Mesophotic coral ecosystems (MCEs) can be defined as light-dependent coral, algal, and sponge communities that occur in the deepest half of the photic zone (starting at 30m and extending to over 150m) in tropical and subtropical regions [1]. The distribution of MCEs in the US Caribbean and elsewhere, including ecologically relevant parameters such as percent living coral cover, reef rugosity, incidence of bleaching, and species diversity, are largely unknown. MCEs are known habitats of commercially important fish species and could serve as refugia for coral reef organisms during times of global climate change.