National Coral Reef Monitoring Program: Towed-diver Surveys of Benthic Habitat, Key Benthic Species, and Marine Debris Sightings of American Samoa in 2015

The towed-diver method is used to conduct benthic surveys, assessing large-scale disturbances (e.g., bleaching) and quantifying benthic components such as habitat complexity/type and the general distribution and abundance patterns of live coral, crustose coralline algae (CCA), macroalgae, and macroinvertebrates. Surveys are conducted 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 which includes percentage cover of total live hard corals, stressed hard corals, soft corals, sand, coralline algae, and macroalgae, and the number of individual macroinvertebrates (crown of thorns starfish (COTS), sea urchins, and giant clams). Benthic habitat complexity and type data are also collected as part of the survey with the following habitat type categories: continuous reef, spur and groove, patch reefs, rock boulders, pavement, rubble flat, sand flats, pinnacle, and wall.

The data were collected around American Samoa as part of the NOAA Pacific Islands Fisheries Science Center (PIFSC), Coral Reef Ecosystem Program (CREP) led mission in 2015. These data can be accessed online via the NOAA National Centers for Environmental Information (NCEI) Ocean Archive.