Global map reveals seagrass meadows under threat—even inside protected areas

A new global analysis finds that many of the world’s most threatened seagrass meadows lie within designated Marine Protected Areas (MPAs), raising urgent questions about the effectiveness of current protections for coastal habitats and offering a chance to rethink global ocean conservation.

The study, led by a team of scientists from the international NGO Project Seagrass, presents one of the most comprehensive global maps ever produced of the human pressures threatening seagrass meadows—vital coastal ecosystems supporting fisheries, and sustaining marine biodiversity in over 150 countries. The work is published in the journal Environmental Research: Ecology.

With help from over 1,000 citizen scientists, the team mapped human pressures on seagrass at over 1,200 sites across 86 countries, finding that most seagrass meadows face multiple combined threats, including coastal development and pollution to impacts from things like boating, destructive fishing and aquaculture.

Strikingly, half of the seagrass sites exposed to human impacts were located within MPAs—areas that are meant to provide refuge from such threats.

“These are supposed to be safe havens for biodiversity,” said lead author Dr. Benjamin Jones. “Instead, we’re finding that many seagrass meadows inside MPAs are under intense and overlapping pressures from human activities on land. That’s a red flag—but also a huge opportunity to rethink how we protect seagrass meadows.”

A wake-up call

By analyzing the data submitted by citizen scientists to SeagrassSpotter.org, the researchers created a high-resolution map of global seagrass vulnerability. The results reveal hotspots of concern in regions like Southeast Asia, the Mediterranean, and parts of the Caribbean—but also bright spots of lower pressure, where conservation action could be both timely and transformative.

Critically, the study exposes a major gap between designation and implementation in the world’s MPA networks—finding that seagrass in 4.4% of the world’s MPAs is under threat.

“Putting a boundary on a map isn’t enough,” said Dr. Jones. “If we’re serious about protecting seagrass meadows—and all the benefits they offer—we need to start managing impacts from land.”

The study calls for immediate action to strengthen protections within existing MPAs, prioritize high-threat zones for urgent intervention, and expand conservation to underrepresented but ecologically rich areas.

“With just a small fraction of seagrass currently protected, the study makes a clear case for smarter marine spatial planning, localized threat reduction, and global cooperation,” said study co-author Dr. Richard Unsworth (also of Swansea University). The findings support the United Nations’ “30×30” goal to protect 30% of Earth’s land and ocean by 2030—but emphasize that quality of protection is just as critical as quantity.

To achieve the Kunming–Montreal Global Biodiversity Framework targets, net seagrass losses of roughly 3,000 km² must be avoided annually from 2030 onwards and ~95,000 km² of these ecosystems must be restored. Meeting these targets requires solving the complex threats that most seagrasses around the world face.

From threats to solutions

By publishing the data from this study in an interactive map, the scientists hope this becomes a critical tool for policymakers, conservationists, and local communities, who can now pinpoint some of the most at-risk areas and focus efforts accordingly.

“Seagrass meadows are quiet powerhouses of the ocean,” said Dr. Jones, “[and] this new map shows us exactly where we need to act—not just to stop loss, but to invest in protection and conservation where it matters most.”

Such conservation solutions, the authors argue, need not always be ocean-based—land-based restoration and watershed management will be critical to combat nutrient pollution.

“These threats are real and widespread. But the solutions are just as real and within reach,” said the team. “By mapping the threats, we’re also mapping the solutions. We know where to act. Now the world needs to do it.”

Citizen science

This global analysis represents the first research study using data from SeagrassSpotter.org, a citizen science platform launched a decade ago to engage the public in seagrass conservation. This milestone marks a significant achievement in seagrass science, showcasing the power of community-driven data collection.

Over the past 10 years, volunteers from around the world have contributed thousands of observations, and Project Seagrass hopes this new research will inspire others to participate, and for fellow scientists to also harness the global dataset.