E/V Nautilus Launches 21-Day Deep-Sea Expedition in Cook Islands

International Expedition Underway in Cook Islands

The E/V Nautilus, operated by the U.S.-based non-profit Ocean Exploration Trust (OET), has embarked on a 21-day deep-sea expedition in the waters of the Cook Islands. Supported by the U.S. National Oceanic and Atmospheric Administration (NOAA) via the Ocean Exploration Cooperative Institute, the mission, titled 'Deep-Sea Habitats of the Cook Islands,' began on October 1, 2025, and is scheduled to conclude on October 21, 2025. This collaborative effort aims to explore previously unmapped abyssal plains and seamounts within the nation's vast Exclusive Economic Zone (EEZ).

Exploring Uncharted Depths and Biodiversity

The primary objective of the expedition is to conduct scientific imaging and cataloging of the seabed and its biological diversity. The international team aboard the 68-meter vessel will collect high-resolution visual observations, environmental data, and physical samples to support studies on the biological and geological context of abyssal plain habitats and the Manihiki Plateau. The Cook Islands' EEZ spans over 770,000 square miles of ocean, much of which remains unexplored. The data gathered will be crucial for informing the management of marine resources within Marae Moana, a large-scale marine managed area that encompasses the entire EEZ.

Collaborative Science and Advanced Technology

This expedition represents a significant partnership between NOAA, OET, and the Cook Islands Seabed Minerals Authority (SBMA). The team includes six local participants from the Cook Islands, representing SBMA and National Environment Services (NES), working alongside international scientists. Dr. Aurora Elmore, a NOAA marine geologist and co-lead scientist for the expedition, stated, 'NOAA is thrilled to be able to bring this research expedition with advanced technologies to assist this important international partnership.' The E/V Nautilus is equipped with advanced tools, including remotely operated vehicles (ROVs) such as Hercules, Atalanta, and Little Hercules, along with mapping and telepresence systems, to explore depths between 4,500-5,500 meters.

Informing Future Management and Public Engagement

The expedition's findings are intended to strengthen the understanding of the Cook Islands' deep-sea environment and inform science-based decision-making regarding marine resources and potential seabed mineral resources. Beverly Stacey-Ataera, Commissioner of the Seabed Minerals Authority, emphasized the expedition's focus on understanding: 'This expedition is about learning more about our Marae Moana — not exploitation, but understanding.' All collected data will be made publicly available to support local management and future decisions by Cook Islanders. Furthermore, the entire expedition is being livestreamed 24/7 on NautilusLive.org, allowing global audiences and classrooms to engage directly with the science team at sea.