National Coral Reef Monitoring Program: Towed-diver Surveys of Large-bodied Fishes of the Mariana Archipelago in 2017 (NCEI Accession 0166382)

The towed-diver method is used to conduct surveys of large-bodied (> 50 cm) fishes in the Hawaiian and Mariana Archipelagos, American Samoa, and the Pacific Remote Island Areas as part of the NOAA National Coral Reef Monitoring Program (NCRMP). A suitable method for assessing relatively large areas of reef habitat, the method involves towing a pair of SCUBA divers—one benthic and one fish—behind a small boat for approximately 50 min following the ~15-m depth contour and covering about 2–3 km of habitat. Each diver is equipped with a towboard and attempts to maintain a constant elevation above the surface of the reef (~1 m) for the duration of the survey. A complete towed-diver survey is divided into 10 5-min segments, with visual observations recorded by 5-min segment.

The visual estimate data provided in this dataset were collected during towed-diver surveys in which the number, size, and species of all large-bodied fishes observed within a visually estimated 5-m transect on either side of the fish diver and 10 m in front were recorded. The data were collected around the Mariana archipelago as part of the NOAA Pacific Islands Fisheries Science Center (PIFSC), Coral Reef Ecosystem Program (CREP) led mission in 2017.