NOAA Divers Complete 1,006-Dive Survey Across Remote Pacific Reefs

NOAA scientists have completed a major coral-reef monitoring campaign spanning American Samoa and the Pacific Islands Heritage Marine National Monument, logging 1,006 scuba dives across one of the most geographically dispersed survey routes in the Pacific.

The team sailed from Honolulu to Jarvis Island, Palmyra Atoll and Kingman Reef before travelling roughly 2,000 kilometres to American Samoa. Survey stops there included Tutuila, Ofu, Olosega, Taʻū, Swains and Rose Atoll, followed by work at Howland and Baker islands on the return voyage.

Divers completed 440 fish surveys and 550 photoquadrat surveys of the seafloor. They also carried out 420 photomosaic surveys, collecting overlapping images that NOAA says will be processed into three-dimensional reef models. Other work included water sampling, carbonate-budget surveys and the deployment or recovery of temperature recorders, calcification units, bioerosion units and diel instrument packages.

The campaign shows the scale and repetition required for scientific diving to turn individual underwater observations into comparable long-term records. The 3D models can help researchers measure changes in reef structure, while repeated fish, coral and water measurements can connect habitat condition with shifts in reef communities and ocean conditions.

NOAA says the islands are generally revisited every three years. The newly collected information now enters analysis, with summary data products expected in about a year. Until that analysis is complete, the dive totals describe survey effort rather than reef health outcomes; the agency has not yet reported whether any surveyed location improved or declined.