The expedition follows Manta Watch’s successful presentation of its research at the Sharks International Conference in Sri Lanka, the world’s largest gathering of shark and ray scientists.
Tracking Giants Across the Pacific: Manta Watch’s Biggest Expedition Yet
By Live Ocean
3 June '26
Read time: 3 min
Article Summary
Main Points
Manta Watch Aotearoa New Zealand is preparing for its biggest expedition yet, with Lydia Green joining a 1,100-nautical-mile voyage from Aotearoa to Tonga to investigate mysterious deaths of endangered oceanic manta rays.
The research will help map a newly emerging migration corridor and support efforts to establish stronger international protections for migratory marine species across the Southwest Pacific.
This latest update from Lydia Green and the Manta Watch Aotearoa team builds on years of groundbreaking research into te whai rahi (oceanic manta rays), one of Aotearoa’s most mysterious and least understood ocean species.
Supported by Live Ocean from 2023–2024, the project has revealed that New Zealand’s manta rays are world record holders, travelling further, diving deeper, and venturing into colder waters than any other known manta population.
With more than 650 sightings recorded and growing evidence of important migration routes across the Pacific, this new expedition marks an exciting next chapter in the effort to better understand and protect these endangered ocean giants.
It’s been a busy few months for Lydia Green and the Manta Watch team! This grassroots charity has been operating out of Aotea for the last six years and is about to embark on its biggest expedition yet.
A collaborative 1,100 nautical mile expedition hosted by Free Range Ocean aboard 50ft sailing vessel FREERANGER will depart Whangārei, Aotearoa New Zealand bound for Nukuʻalofa, Tonga, 3 June 2026. The voyage will follow part of a newly emerging migration corridor for endangered oceanic manta rays between Aotearoa and the Southwest Pacific Islands, helping Green to investigate a concerning pattern of manta ray deaths south of the Tonga identified through satellite tagging.
The research will contribute to ‘blue corridor’ initiatives, which aim to create greater protections for migratory ocean species. Manta Watch Aotearoa New Zealand hopes that the expedition will strengthen the scientific case for international marine protections across the Southwest Pacific and help prevent the extinction of one of the ocean’s most enigmatic species.
“Not many people know that we have Oceanic Mantas in New Zealand,” says Green. “These seven-metre giants have been quietly moving through our waters for generations. But we are seeing signs that these incredible animals are dying outside of New Zealand waters. We need to understand what is happening out there and what is driving these deaths before it is too late.”
The expedition is made possible through volunteer effort, in-kind contributions and support from Another World Adventures, Seakeepers and the Manta Watch New Zealand crowdfunding community.
This expedition comes off the back of Manta Watch Aotearoa New Zealand’s participation in the Sharks International Conference in Sri Lanka. It was the world’s largest international shark, ray, and chimaera scientific conference – where Lydia Green and Junior research assistant Sanaa Nair presented their research to the conference’s 800 participants who represented 83 nationalities. “It was an amazing collaborative success,” says Green.
