Global Manta and Devil Ray Population Declines

A landmark global study led by the Manta Trust and a network of international experts has revealed the first scientifically robust estimate of manta and devil ray (mobulid) mortality worldwide - an alarming 265,000 individuals killed every year.

Published today, Global manta and devil ray population declines: closing policy and management gaps to reduce fisheries mortality, provides a comprehensive global review of mobulid fisheries. The study identifies small-scale fisheries (<15 m vessels) as the source of 87% of mobulid deaths, with the highest-risk hotspots located in India, Indonesia, Sri Lanka, Peru, and Myanmar. Mortality mostly occurs in drift gillnets which are non-selective, and retention is largely driven by demand for gill plates in international markets and, to a lesser extent, meat consumption.

Despite nearly a decade of international protections under CITES Appendix II and CMS Appendices I and II, as well as national measures in over 40 countries, enforcement gaps and ongoing exploitation continue to push mobulids toward extinction.

“This comprehensive picture of mobulid mortality shows how severe fisheries threats are and provides the context needed to prioritise conservation action,” said Betty Laglbauer, lead author of the study. “We now have a data-driven understanding of global catch and of population declines - which underscores the urgency of stronger protections and effective management.”

The release of this study comes at a critical time. The IUCN Red List recently uplisted three oceanic devil ray species to Critically Endangered, marking the last step before extinction in the wild. Meanwhile, global governments will convene at the 20th Conference of the Parties to CITES (CoP20) on 24 November, where they will vote on whether to uplist all mobulid species to CITES Appendix I, the highest level of international protection. If adopted, the decision would prohibit all international commercial trade in mobulid products - a vital step toward halting unsustainable exploitation.

Key Findings from the Study

Drawing on fisheries data, global databases, reports, and expert interviews, the study estimates:

• 264,520 mobulids are caught annually (95% CI: 184,407–344,987).

• Small-scale fisheries account for 87% of total mortality.

• Just five countries — India, Indonesia, Sri Lanka, Myanmar, and Peru — account for 85% of global catch and 87% of total mortality.

• The Indian Ocean is the epicentre of mortality, responsible for 74% of global deaths.

• Drift gillnets are the leading cause of mobulid captures in small-scale fisheries; purse seines dominate in larger fleets.

• Population declines of up to 99% have been documented in some regions.

“Mobulids are among the most charismatic and biologically vulnerable marine animals,” said Dr Guy Stevens, Chief Executive and Co-Founder of the Manta Trust. “This study provides the strongest evidence yet that overfishing, particularly by small-scale coastal fleets, is pushing these species toward collapse. The solutions are clear. What’s needed now is the political will to implement them.”

Closing the Policy Gaps

The study calls for coordinated, science-based action to close existing management and policy gaps. It recommends that all mobulid species be uplisted to CITES Appendix I, which would ban all international commercial trade and close existing loopholes that allow unsustainable exploitation. The authors also urge governments in high-risk fishing nations to implement full national legal protection for mobulids, ensuring retention bans and the promotion of live-release practices.

In addition, the study highlights the need to restrict fishing in critical habitats, such as known aggregation and nursery areas, and to limit the use of drift gillnets and other high-risk fishing gear that cause high incidental mortality. Equally important is the call to actively engage local fishers and coastal communities through education, participatory management, and the development of alternative livelihood programmes, such as shifting to more sustainable fisheries practices, that support conservation goals.

Together, these measures would address both the supply side of mobulid mortality, through stricter fisheries regulation and enforcement, and the demand driving exploitation through international trade.

“Many of these animals are dying as retained bycatch from non-selective fisheries,” said Nidhi D’Costa, co-author and Manta Trust researcher. “Reducing mortality means both protecting species domestically and curbing the demand that fuels international trade.”

This study provides a critical scientific foundation for decision-making ahead of CITES CoP20. With mobulid populations declining sharply across multiple ocean basins, the Manta Trust and its partners are urging governments to take decisive action to prevent the loss of these irreplaceable species.

The public also has an important role to play in supporting these efforts. By backing the #SaveTheMantas campaign and signing the Only One petition, individuals can demonstrate widespread public support for stronger protections and help drive global action to reduce the exploitation of these vulnerable rays. Every voice matters in sending a clear message to decision-makers that immediate action is essential.

FOR MEDIA ENQUIRIES

Contact: Jasmine Corbett
Manta Trust Media and Communications Manager
Email: jasmine.corbett@mantatrust.org

Press Release Credits

Written by: Jasmine Corbett
Images: Photographer’s credit below images – ensure that credit is given if images are used

About the Manta Trust

The Manta Trust is a UK-registered marine conservation charity dedicated to the research and protection of manta and devil rays and their habitats. Through research, education, and collaboration, the Manta Trust works to ensure a sustainable future for these extraordinary creatures.