Saildrone completes mapping of Cayman Islands’ EEZ

Californian company Saildrone has completed a mission to map the Exclusive Economic Zone (EEZ) of the Cayman Islands in the Caribbean, using a Saildrone Surveyor Uncrewed Surface Vehicle (USV). Earlier this year Saildrone and Thales Australia announced a collaboration, funded by the US Office of Naval Research (ONR) to mount a Thales Blue Sentry thin-line towed sonar array on a Surveyor to enhance undersea Maritime Domain Awareness (MDA).

Over the course of 300 mission days off the Cayman Islands, Saildrone surveyed approximately 90,000km² of seabed, in depths ranging from 20m to 7,000m, executing over 900 sound-velocity profile casts to ensure accurate bathymetric data, the company says. One of the priorities of the mission was to survey four fishing banks—60 Mile Bank, Lawfords Bank, Pickle Bank, and 12 Mile Bank—which serve as crucial hotspots of biodiversity supporting fisheries, tourism and recreation and are an indicator of the health of the Cayman Islands’ marine ecosystem.

All raw bathymetric, backscatter and ocean-profile data will now be handed over to the UK Hydrographic Office (UKHO), which will process it under its role as the Primary Charting Authority for the Cayman Islands, before the final data sets are formally delivered to the Cayman Government. The UKHO intends to update its nautical chart portfolio of the Cayman Islands by incorporating the collected data. Additionally, a low-resolution dataset will also be provided to Seabed 2030 to support its goal of mapping the entire global seabed by 2030.

Prior to this survey, the US Navy trialled a fleet of 10 similar Saildrone Voyagers in the Caribbean and Gulf of Mexico under Operation Windward Stack which was designed to integrate crewed and uncrewed systems and collaborate with regional partners and ran from 2021 to 2024. The company says the Saildrone Voyagers were used to increase maritime domain awareness and help US Navy operators learn the best combinations and crewed and uncrewed platforms for different mission types.

The Saildrone fleet managed to deter illegal activity and resulted in fewer illegal migrant boat departures, the company says. The 10 Voyager USVs sailed more than 130,000nm over some 2,700 mission days and detected 116,000 contacts of whom 98,000 did not have AIS activated. According to the US Canter for Naval Analysis the fleet covered an area of 12,500km² at a total cost of $4.25 per square nautical mile per day.

The Cayman Islands survey mission was philanthropically funded by the London & Amsterdam Trust Company Limited, a Cayman-based organization that wants to leave a lasting legacy to the Cayman Islands.

Prior to the Saildrone survey, the company says, the Cayman Islands had limited data available of its EEZ; the extent to which the Cayman EEZ had been surveyed with modern multibeam sonar technology was only 20,000km² of seafloor concentrated around the deep water of the Cayman Trench.

For small island nations such as the Cayman Islands, ocean mapping unlocks critical opportunities in the Blue Economy, according to Saildrone: a high-resolution bathymetric map of a country’s EEZ is a prerequisite for exploring and managing natural resources in waters extending up to 200 nautical miles from its shores.

During the mission, Saildrone faced numerous operational challenges, says the company, including unprecedented sargassum blooms and severe weather threats, which exacerbated the operational difficulties of delivering high-resolution seabed mapping in the open ocean.

Saildrone developed new approaches to clearing the Sound Velocity Profiler (SVP) and enhanced remote diagnostics to detect biofouling early. Operating safely and consistently during severe weather helped validate the Surveyor’s proven capability to remain on survey up to sea state seven, the company points out.

“This mission is a testament to the power of Saildrone vehicles in delivering ocean mapping at a scale and resolution that was previously prohibitively expensive for small island nations,” said Brian Connon, Saildrone VP Ocean Mapping. “Delivering mission-critical operations in sargassum-filled, hurricane-exposed waters demonstrates the resilience of Saildrone’s unmanned mapping services and the prospects it holds for nations worldwide.”

Following the success of this mission, Saildrone says it is looking forward to opportunities to map the EEZs of additional Caribbean nations.