Use of Satellite Telemetry on Pelagic Seabirds (Juvenile Sooty Terns) to Identify Potential Marine Protected Areas

The Seychelles Marine Spatial Plan (SMSP) project is a data-driven program to align blue economy objectives (mainly promoting marine-based food security, livelihood programs, and value-adding businesses) with climate change adaptation and biodiversity protection initiatives. An essential aspect of the SMSP is the identification of new biodiversity areas, such as breeding grounds of rare or endangered species and critical foraging areas, which need protection and conservation.

The sooty tern, the most abundant seabird in the Seychelles, can be a good proxy for identifying productive foraging areas in the country. Prior ringing, geolocator, and GPS investigations reveal that these birds spend most of their adult life at sea and return to land only to breed. No prior data is available on where juvenile sooty terns go after their independence from parental care and their first departure from the breeding colony. It is postulated that these birds go to areas with predictable food abundance. These areas may be important foraging sites for many top predators, which warrants high conservation significance.

The project aimed to fill this knowledge gap by tagging juvenile sooty terns and using satellite telemetry to track their departure and flight patterns over two years. Satellite telemetry, which uses trackers powered with solar-charged batteries, can continuously transmit location data and show the interim foraging locations of juvenile sooty terns between first departure and return to breeding on land, a critical development stage of the bird.

Bird Island (Aride) was chosen as the ideal research area due to the known dense nesting population and high tolerance of resident birds toward research activity disturbances.

The results of the project reveal that the juveniles are able to spread across the Indian Ocean to the Somali coast, the Arabian Sea, off the coast of west India, the Bay of Bengal, the Andaman/Nicobar islands, west of Maldives, Cocos (Keeling) Island, and south of Sri Lanka, among other locations within months of fledging and follow the same areas used by adults when not breeding (Jaeger et al., 2017). The project team shared these findings, including the spatial data downloaded every two weeks and the generated flight and dispersion maps, with the SMSP team to help inform conservation and marine protection efforts.

By assisting in identifying potential marine protected areas, the project contributes to national and international biodiversity protection and promotes the use of innovative technologies in conservation policy.