By Sharon Atieno
Despite seagrass meadows being a powerful nature-based climate solution and helping to sustain communities hard-hit by stressors such as the COVID-19 pandemic, these ecosystems are decreasing, a new report finds.
Seagrass meadows are among the most common coastal habitats on earth, covering more than 300,000 km2 in at least 159 countries. However, an estimated 7 per cent of seagrass habitat is being lost worldwide each year, and at least 22 of the world’s 72 seagrass species are in decline.
Since the late 19th century, almost 30 per cent of known seagrass area across the globe has been lost with the main threats to seagrass meadows being urban, industrial, and agricultural run-off; coastal development; dredging; unregulated fishing and boating activities, and climate change.
The report titled: Out of the Blue: The Value of Seagrasses to the Environment and to People, was released by the United Nations Environment Programme (UNEP) together with GRID-Arendal and the UN Environment Programme World Conservation Monitoring Centre (UNEP-WCMC).
The report finds that there is an urgent need to address these key cumulative drivers of seagrass degradation through integrated policies and cross-sectoral management measures, reflecting dependencies at the land–sea interface.
“Maintaining the health of seagrass ecosystems – which provide food and livelihoods to hundreds of millions of people, support rich biodiversity, and constitute one of the planet’s most efficient stores of carbon – is important for healthy marine life and for healthy people around the world,” said Susan Gardner, Director of Ecosystems Division. “Seagrasses represent powerful nature-based solutions to the climate challenge and sustainable development.”
Though seagrass ecosystems cover only 0.1 per cent of the ocean floor, they are highly efficient carbon sinks, storing up to 18 per cent of the world’s oceanic carbon, thus playing a huge role in combating the climate crisis.
“Given the carbon storage and sequestration potential of seagrass ecosystems, including them in nationally determined contributions (NDCs) can help nations achieve their targets under the Paris Agreement and the United Nations Framework Convention on Climate Change (UNFCCC),” the report reads.
The well-being of human communities is closely tied to the health of seagrass meadows, for instance, in Tanzania, a decline in seagrass was found to have a negative impact on the livelihoods of women who collect invertebrates, such as clams, sea snails and sea urchins, from seagrass meadows.
In the North Atlantic, seagrass provides critical habitat to juvenile Atlantic cod, a major commercial species that is fished by fleets from more than a dozen nations. Seagrasses are also part of the cultural fabric of many island communities. For example, in the Solomon Islands, fishers twist seagrass leaves together and shout to seagrass spirits for good luck.
“Seagrasses are the super ecosystems of our oceans, providing an incredible range of benefits to people around the world. Yet, while their flashier counterparts attract more attention, they remain among the most unheralded aquatic environments on Earth. The Out of the Blue report showcases the many ways that seagrasses help people thrive and sustain the healthy natural environment that we all depend on,” said Dr. Maria Potouroglou, seagrass scientist at GRID-Arendal and lead editor of the report.
Despite their importance, new data suggest that seagrasses are among the least protected coastal habitats. Only 26 per cent of recorded seagrass meadows fall within Marine Protected Areas (MPAs) compared with 40 per cent of coral reefs and 43 per cent of mangroves.
“Seagrasses can help us solve our biggest environmental challenges. They purify water, they protect us from storms, they provide food to hundreds of millions of people, they support rich biodiversity, and they efficiently store carbon. In light of everything seagrasses do for people and nature, protecting and restoring them is vital”, said Ronald Jumeau, Permanent Representative to the United Nations and Ambassador for Climate Change, Republic of Seychelles.
The report notes that financing of seagrass conservation and restoration is an important hurdle in sustainably managing seagrass ecosystems, implementing policies effectively and tracking progress towards management and policy objectives.
Moreover, conserving and restoring seagrass meadows can contribute to achieving as many as 10 of the UN Sustainable Development Goals as well as the goals of the Paris Agreement and the Convention on Biological Diversity.
Some of the actions recommended by the report include: developing national action plans for seagrass ecosystems; increasing funding at all levels for comprehensive actions required to conserve and sustainably manage seagrass ecosystems; developing a comprehensive global map of seagrass distribution and health, and designating more MPAs or locally managed marine areas (LMMAs) that include or focus on management measures for seagrass ecosystems among others.