Simon Hilbourne
Who I am
Born and raised overseas, I spent several years growing up in Thailand, where I learned to scuba dive at a young age. I completed my Divemaster qualification days after turning 18 and then spent a gap year working as a dive instructor on the Great Barrier Reef. It was always in the back of my mind, though, that my passion and fascination was in the animals rather than the tourism side of things.
Four years of a marine biology degree in Southampton, UK, was long enough in a cold climate, so I moved back to South-East Asia to volunteer in whale shark research in the Philippines. In 2016, I joined the Manta Trust as a volunteer for the Maldives Manta Conservation Programme (MMCP). Over the years I grew into different research and media roles in the MMCP and wider Manta Trust.
My current professional career juggles scientific research and media production while maintaining a strong focus on conservation. At the same time as working as an underwater cameraman, I head up the Maldives oceanic manta research project under the MMCP. In recent years, I have also founded a UK-based non-profit called Fish Free February, which aims to connect people with the issues surrounding fisheries and, through awareness and education, encourage them to reduce their seafood consumption or make more informed consumer decisions.
Where I work
My research focuses on the Maldives archipelago. Located in the central north Indian Ocean, the archipelago comprises 1,200 islands and hundreds more coral reefs. All sharks and rays have been protected in the Maldives for over a decade, making it a sanctuary for these special animals.
The Maldives is widely known as one of the best places in the world to see reef manta rays, and the MMCP, the founding project of the Manta Trust, has been documenting the manta population here for nearly two decades. The country hosts the largest reef manta ray population in the world, with more than 6,000 individuals identified by 2024. Oceanic manta rays occur here too and, also in 2024, we documented the 1,000th oceanic manta ray in the Maldives, which makes this the third-largest known population of this species.
About 85% of the oceanic manta ray sightings in the Maldives have come from Fuvahmulah Atoll, a small, four-kilometre-long (2.5-mile-long) island just south of the equator. This island, most famous for its tiger shark aggregation, is a magnet for all sorts of large marine animals and seems to be a particular favourite for oceanic manta rays. I first visited Fuvahmulah in 2018 when tourism was in its infancy, and have seen its popularity explode as divers flock to the island from around the world. Our oceanic manta research has already contributed to Fuvahmulah being listed as a UNESCO Biosphere Reserve and an ‘Important Shark and Ray Area’.
Sadly, in some of the countries neighbouring the Maldives, oceanic manta rays and other mobulid species are caught and landed in fisheries. Sri Lanka, the Maldives’ closest neighbour, hosts the largest mobula fishery in the world. Blue Resources Trust’s shark and ray fisheries project is affiliated to the Manta Trust working in that country, and we are collaborating with its team to collect tissue samples from Sri Lanka for comparison.
What I do
Oceanic manta ray sightings in the Maldives are seasonal, with a peak period of sightings usually around March and April. Outside this period, sightings are rare and widely distributed across the country. As a result, we rely on an extensive network of resort marine biologists, live-aboard and dive centre staff and the public to submit sighting records and photos of oceanic manta rays they see.
Starting around March each year, the project focuses on Fuvahmulah Atoll. A seasonal peak in oceanic manta sightings provides the only feasible opportunity to research this sub-population. Since 2019, I have managed a small team of researchers on Fuvahmulah who conduct regular boat, drone, snorkel and dive surveys for oceanic mantas. The primary objective of these field seasons has been to build a basic understanding of the population using photo identification. We’re starting to figure out things like when the season is, how many mantas there are, if it’s the same mantas returning each year, whether they are mostly males or females, if they are feeding or cleaning in the area, and so on.
In recent years, we have started to try and use more advanced research techniques, including satellite tagging, tissue biopsy sampling and animal-borne cameras to understand the manta rays’ movements and migrations and why they aggregate around Fuvahmulah.
At the same time, I am collaborating with Blue Resources Trust in Sri Lanka, whose shark and ray project monitors fish landing sites across the country. During field surveys, team members visit fish markets around the country and document the sharks and rays caught and landed by the fisheries. They are collecting tissue samples from oceanic manta rays landed by fishers for genetic and stable isotope comparison with samples we collect in the Maldives.