Let’s get to know the French Polynesia Manta Project!

January 2024

The French Polynesia Manta Project, has been an affiliate project of the Manta Trust since 2015, and since then it has grown from strength to strength! We thought it was about time to introduce you to this incredible project, and the Bora Bora project manager Virginie Poly is here to tell you all about it…

‘French Polynesia is located in the South Pacific. Made up of 118 islands spread over 5 archipelagos, high islands and atolls are found side by side, offering an incredible wealth of different ecosystems. French Polynesia is renowned for its breathtaking beaches with crystal clear waters, but its coral reefs are also worth exploring. The reefs are home to a wide variety of marine life, including manta rays. Both reef and oceanic mantas are found, although reef manta rays are more easily observed inside lagoons which are ideal cleaning areas.

A reef manta ray on a cleaning station in Bora Bora. © Simon Hilbourne.

Since 2015 Manta Trust has been collecting data on the manta ray’s population over French Polynesia with a focus on Bora Bora for the past 4 years through a partnership with Conrad Bora Bora Nui Resort.

A researcher takes an ID shot of a reef manta ray on a cleaning station in Bora Bora. © Alice Carpentier

A local project began collecting data in 2002 in Bora Bora, enabling us to monitor the population over 22 years. More than 1,100 reef manta rays have been identified in French Polynesia between 2001 and 2023. Three individuals have been tracked for over 20 years and a strong long-term site fidelity had been recorded for some islands reaching up to 93% of resighting. High breeding activity is recorded in French Polynesia lagoons, with sometimes long courtship events lasting several weeks, numerous pregnant manta rays observed, and a dozen babies counted in the lagoons. One female has even been observed pregnant for several years in a row. All this could make French Polynesia a potential nursery ground for reef manta rays.

A reef manta ray pup in Bora Bora. © Virginie Poly

The project also focuses on movements between islands. At least 40 other manta rays are observed on more than one island and one reef manta was even seen on two islands 400km apart. This is the largest movement recorded by the photo identification program in French Polynesia. Since monitoring efforts have been irregular for a long time between sites, the available data did not allow us to determine whether these individuals made these movements on a punctual, seasonal, or annual basis. Being able to increase Citizen Science participation and starting the use of trackers would also highly increase our knowledge.

As an attractive holiday destination for honeymooners, Bora Bora is French Polynesia's most popular tourist destination. Manta rays are part high value in ecotourism, attracting snorkelers and divers from all around the world. This has led to mass boat tourism and disruption. Even though manta rays are classified in the main category of protected species by the Polynesian Code of Environment, there are no existing official regulations to protect them. The Polynesian manta project is monitoring daily harmful tourist behavior and recording injured manta rays’ data. Workshops and information meeting are provided to the local snorkeling guides. The aim is to ensure that the manta trust code of conduct is applied by all tourism service providers, and to eventually create official local regulations.

A reef manta ray with a boat propeller injury in Bora Bora. © Virginie Poly

Since 2021, Manta Trust has been also working with the Bora Bora Middle School to raise students' awareness of manta ray conservation. Through sessions presenting the species and taking them to the water with the animals, students are encouraged to (re)discover their lagoon and the approach to an animal sacred in Polynesia, also considered to be an animal spirit or a moving temple.