While the distribution and status of shallow - water reefs in many parts of the world has been well documented in the last 40 years, benthic characterization studies and large - scale mapping of deep reef habitats, are very rare. Recent studies on mesophotic coral ecosystems (30 - 100 m) in the eastern Puerto Rico Shelf describe abundant and structurally complex coral reefs on low - gradient platforms at depths of 35 - 45 m. Information on deep coral communities (> 200 m depth) in the US Caribbean is even more scarce and largely limited to taxonomic listings from incidental collections by coral entanglement devices. In recent years, the Seabed autonomous underwater vehicle (AUV), which was designed for high - resolution underwater optical and acoustic imaging, has provided unprecedented information on the distribution, community structure, and status of mesophotic reefs throughout th e U.S. Caribbean. Preliminary surveys of two deep coral communities off western Puerto Rico show diverse azooxanthellate coral and invertebrate fauna at depths of over 200 m. For both mesophotic and deep coral communities, the AUV benthic assessments can provide the required information for selecting unique areas of high biodiversity and structural complexity for habitat protection and ecosystem based management.
Autonomous Underwater Vehicle (AUV)