Genetic insights inform manta ray conservation

Understanding diversity in declining manta ray species points to conservation management policies to prevent overfishing.

Research into the genetic diversity and population structure of manta rays has shed light on ways to support the conservation of these iconic marine species.

In a study spanning over a decade, an international team of researchers led by the Royal (Dick) School of Veterinary Studies used advanced genomic sequencing techniques to study tissue samples of two closely related manta ray species – the oceanic manta ray and the reef manta ray.

Findings highlight the need for local and national conservation management of reef manta rays, and management at all levels – local, regional, and international – to protect oceanic manta rays.

Population structure

Genomic tests indicated a stark distinction in how populations are structured between the two species. 

Reef manta rays showed distinct genetic differences between population groups, suggesting individuals usually don’t mix with those of other populations.

Meanwhile, oceanic manta rays showed less defined population structures, suggesting individuals in this species move across various populations during long-distance migrations, which often cross international boundaries.

Conservation plans

These findings underscore the vulnerability of oceanic manta populations to fishing activities along migratory corridors and in areas of the oceans where they birth and raise offspring.

Movements of manta rays across borders could significantly impact the effectiveness of management efforts, and coordinated international conservation strategies are needed, the team says.

This research was published in Molecular Ecology, in collaboration with colleagues from The Manta Trust, Wales, Australia, Mexico, the US, the Philippines and South Africa, and funded by NERC, the Save Our Seas Foundation and The People’s Trust for Endangered Species.

Reef and oceanic manta rays are two of the most charismatic species in our oceans. People love to interact with them, dive with them and swim with them, but the whole group is threatened with extinction through overfishing.

“The cooperative nature of this study underscores the global effort required for effective marine conservation, as well as providing empirical data supporting concerns about the fishing industry's impact on manta populations while reinforcing the need for robust enforcement of international conservation policies.

Oceanic Manta Ray
Image credit: Guy Stevens/The Manta Trust

Related links

Scientific publication