The "TAMATAROA Project" is a research and conservation initiative dedicated to the great hammerhead shark (Sphyrna mokarran) in French Polynesia, launched in 2023 and scheduled to run until 2026.

Jointly supported by Andromède Océanologie, Gombessa Expéditions and the Mokarran Protection Society, this project aims to fill the scientific knowledge gap on this critically endangered species, using innovative, non-invasive study methods. It relies on scientific collaboration, citizen participation, and integrates cultural and awareness-raising dimensions. The main study areas are the Rangiroa and Tikehau atolls in the Tuamotu archipelago, where the hammerhead shark finds refuge thanks to protection measures established in French Polynesia. The project aims to characterize the hammerhead shark population, study their ecology and behavior, and identify key areas for their conservation.

Andromède Océanologie :

Gombessa Expéditions :

The approach proposed as part of the TAMATAROA project is unprecedented for great hammerhead shark monitoring. It consists not in attracting the animal to the scientist, but in going to meet it, in-situ, without using any method of attraction, in order to carry out all the scientific monitoring protocols in the least invasive way possible, without constraining the animal or modifying its behavior. Meeting this challenge on one of the most difficult shark species to observe in its natural environment will pave the way for a new, more ethical and respectful approach to the study of large marine predators. To overcome the constraints associated with this method of approach and study, experimental scientific protocols will be put in place, drawing on extensive knowledge of the field, recognized scientific expertise and the development of innovative methods and tools. These protocols were tested and validated during the preliminary mission carried out in 2023 by the same team as for this project. To optimize the chances of success, this method requires daily dives throughout the great hammerhead aggregation period (December to April).

Each day, pairs of scientific divers will take it in turns to cover the six hours during which the current is conducive to observations and the deployment of monitoring protocols (In coming current).

The project also involves the deployment of a network of acoustic beacons, unprecedented in the Central Pacific and specially adapted to species that do not, or only rarely, surface. The aim is to track the movements of around thirty great hammerhead sharks on Rangiroa and neighboring atolls over a 3-year period.

1 - Innovative tools specially developed to meet the project's challenges

The absence of capture and attraction methods means that opportunities for encounters with the animal are rarer and more ephemeral. It is therefore essential to optimize the approach and data collection processes. Two new tools have been specially developed to meet these constraints, while maintaining optimum efficiency and safety for divers and animals alike :

- A silent underwater thruster developed with the manufacturer SUEX, which facilitates the diver's movements in strong currents, while limiting the noise pollution likely to scare away sharks;

- An all-in-one scientific tool that can be used in situ to collect a wide range of data in a very short time. The system, operated by a diver, is based on an underwater crossbow specially designed for scientific use. The crossbow is equipped with a laser photogrammetry system for identifying and measuring individuals, and a dual-purpose arrow system that can be used in a single shot to perform a biopsy and attach a beacon to track movements.

2 - An unprecedented multidisciplinary and international scientific collaboration.

In view of the complexity of data collection, and the urgent need to better understand the life cycle of the great hammerhead shark in order to protect it, a veritable network of scientific collaborators has been mobilized to make their specialties available to the project :

• The University of French Polynesia (UPF), based in Tahiti, will be represented by doctoral student Tatiana Boube. She will be conducting her thesis project specifically on the TAMATAROA program, under the supervision of Dr. Gaertner (Head of the "Oceanic Island Ecosystems" research unit at the UPF and head of research at the IRD), co-supervised by Dr. Papastamatiou (Florida International University, USA) and Dr. Huveneers (Flinder University, Australia). A member of the Mokarran Protection Society, she also initiated the first scientific work on great hammerhead sharks in French Polynesia. She is the author of the first scientific publication to be published on the study of the great hammerhead shark in Polynesia. Her thesis work will involve processing and publishing much of the data collected as part of the TAMATAROA project. Along with her co-supervisors, she will be one of the key scientific figures on the TAMATAROA team.

• Flinder University, based in Adelaide, Australia, will be represented by Dr. Huveneers (Director of the Coastal and Marine Research Consortium, and head of the Southern Hemisphere Shark Ecology Research Group SSEG). His research group focuses on the biology, ecology and population status of sharks and rays, as well as assessing their vulnerability to fishing pressure, human interactions and public perception. His team also provides scientific advice to managers and decision-makers on issues relating to sharks, rays and chimaeras. DoctorHuveneers co-directed the Australian Acoustic Monitoring Network in charge of over 1,000 receivers. He has led or contributed to studies on the movement patterns of a wide range of species, including reef sharks, tiger sharks, whale sharks and white sharks, worldwide. He has published over 150 papers and is one of the most prolific authors of scientific publications on sharks worldwide. As part of this project, Doctor Huveneers will contribute to the study of great hammerhead shark movement ecology and the identification of residence factors.

• Florida International University, based in the USA, is represented by Dr. Papastamatiou (Predator Ecology and Conservation Laboratory at the Environmental Institute of the Department of Biological Sciences) : he studies the physiological and behavioral ecology of sharks and other predators, and uses this information to contribute to conservation efforts. He has published over 100 scientific papers, and his research has been carried out all over the world, including Mexico, the Bahamas, Japan, the Central and South Pacific, the Galapagos and Alaska. He is editor-in-chief of two scientific journals (Animal Biotelemetry, Oecologia) and reviewer for many leading scientific journals. His experience in monitoring great hammerhead sharks in the Bahamas will provide essential skills for the project.

• The University of Montpellier is represented by Dr. Mourier (Marine Behavioral Ecology, UMR MARBEC, Marine Biodiversity, Exploitation & Conservation" (CNRS, IFREMER, IRD, UM). He has long worked at CRIOBE on the behavioral ecology of blacktip sharks, using various approaches such as photo-identification, telemetry or genetic matching analyses to better understand the functioning of a population on an island scale. He is particularly interested in social relations (social networks), movements and philopatry. His field of research is spatial and behavioral ecology at the level of individuals and populations. As part of this project, Dr. Mourier will contribute to the behavioral study of great hammerhead sharks.

3 - A project fully integrated into its territory to produce concrete effects as quickly as possible

The TAMATAROA Project, perfectly in line with MPS values, is integrated into the Rangiroa territory through close collaboration with local communities, institutions and users of the marine environment. This integration manifests itself in several ways :

• Citizen and Collaborative Participation : The project actively engages local citizens, fishermen, divers, and other marine users in collecting data and sharing observations, thus fostering a participatory conservation approach informed by local knowledge.
• Institutional and cultural collaboration : The project works in close collaboration with local institutions such as the commune of Rangiroa and the DIREN, and integrates Polynesian cultural and traditional aspects into its conservation approach.
• Training and awareness-raising : Specific training courses on research protocols are organized for local collaborators, reinforcing their capacities and their active participation in the project. Whether in schools, diving clubs, with fishermen or excursionists, events and actions are organized to raise awareness of the project.
• Integration with local conservation policies : The project is aligned with local environmental policies, contributing to the preservation of sensitive natural areas and the sustainable management of marine resources, and in particular to the work of the PGEM currently under construction in Rangiroa.

These collaborative and participatory approaches ensure that the project has a concrete impact on Rangiroa, not only in terms of scientific research, but also by strengthening conservation and environmental awareness within the local community.