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For many locals and tourists, Praslin Island in Seychelles is synonymous with paradise. From the white sands of Anse Lazio, frequently voted as one of the top beaches in the world, to the endemic species of the jungle, to the colorful coral reefs in Curieuse Marine Park, Praslin is filled with both beauty and biodiversity.

But, as events at one site on the northwest side of the island demonstrate, this paradise is precarious.

The Plaine Hollandaise-Pasquière wetlands, which cover a combined 7 hectares, have been steadily degrading due to human activities. “Thirty to forty years ago, forest fires burned the area, which caused degradation in the mountains,” explains Elvina Henriette of the Terrestrial Restoration Action Society of Seychelles (TRASS). “This degradation then causes soil to flow down into the wetlands.”

Not only does erosion allow invasive species to grow, threatening the biodiversity of the wetlands, it also prevents the wetland from performing its natural functions – like flood prevention. Roads and other infrastructure around Plaine Hollandaise are frequently at risk of flooding. Moreover, the excess soil gushes into the sea, turning the normally turquoise water red and covering coral reefs, sandbanks, and seagrass – the very attractions that make Curieuse Marine Park worthy of protection and a tourism attraction.

Reviving the wetlands

A project by TRASS, supported by the United Nations Environment Programme (UNEP), aims to rehabilitate the wetland, starting with restoring the degraded foothills with anti-erosion measures. One idea for such a measure came from local residents, who had grown tired of the constant threat of floods. They helped gather and transport palm leaves to construct a physical barrier to stabilize the soil. They also placed coconut mats and blankets made of natural products, like coconut coir, a biodegradable textile, on steep slopes, trapping soil and allowing vegetation to take root.

Together with schoolchildren and the local community, the project is also working to restore the natural biodiversity of the wetlands by weeding out invasive plants and replacing them with native species. Some 5,000 seedlings have already been sown. These activities led to a startling discovery – the Sooglossid frog, an endangered species found only in Seychelles. Researchers had thought the frog only lived at altitudes above 100 meters, not at sea level where the wetlands lie, said Henriette. Other endemic or threatened species discovered in the wetlands include the Seychelles tree frog and the tiger chameleon. “This shows that the wetland is even more important to biodiversity than we originally thought,” said Henriette.

As a result of the project, a rehabilitated Plaine Hollandaise will help safeguard Seychelles’ unique and precious species. The restored wetland will also provide both economic security, by protecting the world-renowned coral reefs and beaches of Curieuse Marine Park, and physical security, by reducing the occurrence of floods.

Safeguarding coastal zones

The project is funded by the Global Environment Facility through the Implementation of the Strategic Action Programme for the Protection of the Western Indian Ocean from Land-Based Sources and Activities, executed by the Nairobi Convention. This initiative helps reduce land-based stresses by protecting critical habitats, improving water quality, and managing river flows.

The Nairobi Convention, part of UNEP’s Regional Seas Programme, serves as a platform for governments, civil society, and the private sector to work together for the sustainable management and use of the Western Indian Ocean’s marine and coastal environment. 

It’s part of a bigger effort by UNEP to safeguard the world’s marine habitats and prevent what scientists warn is the looming extinction of up to 1 million species.

The Plaine Hollandaise project and others will help Seychelles ensure that the biodiversity hotspots and crucial marine and coastal ecosystems – which provide both food, employment, and storm protection – around its 115 islands continue to provide these ecosystem services.

The project is also designed to help Seychelles achieve its targets under Sustainable Development Goal 14, under which it committed to sustainably manage and protect its marine and coastal ecosystems, as well as future targets under the Global Biodiversity Framework, an ambitious plan to ensure that society is living in harmony with nature by 2050.

A rehabilitated Plaine Hollandaise would also be a key accomplishment during the UN Decade on Ecosystem Restoration, a global push to revive natural spaces that began in June. Finally, with 90 percent of lowland wetlands in Seychelles being degraded, the project will have key lessons to share as partners work to restore other wetlands both within and outside the country, say participants.

This piece was originally published by the UN Environment Programme.