Two research cruises were conducted in 2012 and 2013 to the region of Pulley Ridge and Dry Tortugas to study and survey the mesophotic reef communities and fish populations. The University of Miami’s R/V Walton Smith Cruise No. WS1213 was conducted from August 14 to 25, 2012 and Cruise No. WS1312 was conducted from August 12 to 27, 2013. Pulley Ridge is the deepest known photosynthetic coral reef in continental U.S. waters and is located in the Gulf of Mexico, 100 miles west of the Dry Tortugas at the far end of the Florida Keys. This research and cruises were funded by the NOAA-NOS-NCCOS grant titled ‘Connectivity of the Pulley Ridge – South Florida Coral Reef Ecosystem: Processes to Decision-Support Tools’. Ship and ROV time was funded in part by the Cooperative Institute for Ocean Exploration, Research, and Technology (CIOERT) at Harbor Branch Oceanographic Institute-Florida Atlantic University (HBOI-FAU). This cruise was conducted in collaboration with the University of Miami, HBOI CIOERT, NOAA Fisheries, and the University of North Carolina at Wilmington (UNCW) which provided the UNCW Super Phantom S2 ROV.