BBC News reports that more than 100 scientists from 28 countries, led by Dr Richard Unsworth of Swansea University, have called for global action to protect seagrass meadows.
Seagrasses are flowering plants that form dense underwater beds in shallow water.
Distinct from seaweed, the plants provide shelter and food for a large range of animals, including fish, marine mammals and birds.
Many seagrass meadows have been lost because of human activities, say researchers.
In a statement, the scientists said: "Seagrass meadows are important fish nurseries and key fishing grounds around the world.
"The loss of seagrass puts the livelihoods of hundreds of millions of people at risk and exposes many people to increasing levels of poverty.
"Seagrass loss also places the viability of our remaining populations of green turtle, dugong and species of seahorse at risk.
"Seagrass loss should not be an option." Read more
Dr Richard Unsworth was also interviewed on BBC Radio World Service’s Newsroom programme about the global threat to seagrass meadows. Listen again (14 minutes in)
- Thursday 13 October 2016 13.26 BST
- Thursday 13 October 2016 12.54 BST
- College of Science