NOAA Okeanos Explorer uncovers new species and nodule fields in Cook Islands deep-sea expedition
NOAA’s Okeanos Explorer completed a 26-day deep-sea expedition in Cook Islands waters in August 2026, recovering 23 potential new species and confirming extensive polymetallic nodule fields.
The 2026 Cook Islands ROV Exploration aboard NOAA Ship Okeanos Explorer took place from July 19 to August 13, 2026, a 26-day partnership cruise between NOAA and the Cook Islands Seabed Minerals Authority to map and characterize deep-sea habitats in the Cook Islands EEZ, with a formal welcome ceremony held in Rarotonga on August 17, 2026.
Cook Islands officials described the expedition’s findings as revealing waters teeming with life, a characterization that aligns with the 23 potential new biological specimens recovered during the 14 ROV dives. The scope of biological diversity recorded across the 26-day cruise surprised local stakeholders, who noted the density of organisms observed in areas previously unmapped.
Unexpectedly extensive polymetallic nodule fields were confirmed in the Cook Islands EEZ during the expedition, a finding that adds new context to the region’s deep-sea mineral resources. The nodule fields were not a primary target of the cruise, which was focused on habitat mapping and biological sampling, making their scale and distribution a notable secondary outcome.
The 14 ROV dives yielded more than 400 total samples, with the 23 potential new biological specimens representing a significant addition to the known biodiversity of the Cook Islands’ deep ocean. Each sample was collected under strict protocols to support both scientific research and the Cook Islands’ ongoing efforts to document its marine territories.
For the Cook Islands, the expedition was explicitly framed as a tool to build national knowledge of its deep-ocean environments, a core goal of the partnership between local authorities and NOAA. The formal welcome ceremony held for the Okeanos Explorer team in Rarotonga on August 17 underscored the local significance of the research, which marks a step forward in the country’s ability to manage its EEZ resources independently.