Seagrass Protections Can Lead to Big Wins for Our Ocean, People, and Governments
Coastal habitat has value far beyond shorelines, including in efforts to address climate change
In the coastal waters across much of our planet are meadows of seagrass that are critical to the health of our ocean. Seagrasses evolved millions of years ago when flowering plants on land took up residence in the sea. Now, the estimated 72 species of seagrass fringe every continent except Antarctica. Similar to terrestrial plants, seagrasses have roots, stems, and leaves. They bloom for a short period of time each year, and currents carry their pollen to flowers across the meadow. Although they typically grow in shallow waters, seagrasses have also been found in areas deeper than 40 meters (131 feet), where the sun’s reach can be weak.
Seagrasses are critical habitat for a multitude of fish, invertebrate, and other species. Juvenile fish shelter from predators in the canopy of the meadow, using seagrass as their nurseries during this perilous time of development. Animals such as turtles, manatees, and dugongs visit meadows to feed on seagrass leaves.
Humans also rely on this habitat. Many commercially important species begin their lives on the seagrass bed. Without this crucial habitat, there would be fewer fish to catch and livelihoods could be lost. Experts estimate that one-fifth of the world’s most-landed fish species use seagrass as nursery areas. But it’s not only large-scale fisheries that benefit: Artisanal fishers worldwide ply seagrass meadows with small boats or harvest mollusks and other invertebrates from the shallows.
In addition to their biodiversity benefits, seagrasses play an outsized role in helping communities adapt to climate change and mitigate its effects. Meadows buffer coastal communities from the full impact of waves, a service that is becoming more valuable with the increasing frequency and severity of storms. The soil beneath seagrass can also store large amounts of atmosphere-warming carbon: Experts estimate that around 10% of the total organic carbon sequestered in the ocean is buried in seagrass beds.
But seagrass worldwide is being lost at an alarming rate. Almost 30% of the known seagrass coverage has vanished since the 19th century, a decline driven by water quality, coastal development, pollution, and destructive fishing practices. The estimated rate of seagrass loss parallels those of mangroves and coral reefs, and scientists say that this habitat is now among the most threatened ecosystems on earth.
Although the current situation appears dire, there is hope. Countries around the world are recognizing the biodiversity and the economic and climate value of seagrass in their waters. International climate policy instruments such as the Paris Agreement provide an avenue for countries to include the protection of these vital habitats.
In fact, healthy seagrass meadows are among the nature-based solutions that governments can include alongside carbon emission reduction plans to help in the global fight against climate change. Safeguarding these areas through climate policy can be a triple win for countries by protecting biodiversity, which is good for fishing and tourism; making shorelines and coastal communities more resilient to storm surge and sea level rise; and absorbing carbon from the atmosphere, which in turn supports climate mitigation.
That’s why a growing number of nations are recognizing seagrass protection as a viable component to current and future climate commitments, and many governments are mapping seagrasses and planning or launching restoration projects. More nations must act to protect these vibrant, diverse ecosystems that are critical to a healthy ocean, coastal communities, and the global effort to address climate change—benefits that extend well beyond the meadow.
Stacy Baez manages the scientific portfolio for The Pew Charitable Trusts’ Protecting Coastal Wetlands and Coral Reefs project.