Seychelles Seagrass and Carbon Mapping Project  |22 December 2021

The update on the ongoing mapping exercise in Seychelles waters to determine the coverage and carbon storage capacity of Seychelles’ seagrass (Photo: Jude Morel)

 Project to estimate the country’s ecosystem’s carbon stocks in progress

More public relation image programme is needed in an effort to make people more appreciative of the marine eco-system, including the seagrass and its contribution toward the natural marine habitat.

Seagrass meadows store vast amounts of atmosphere-warming carbon in their underlying soil and are a nature-based solution to climate change.

Dr Jeanne Mortimer launched the appeal on Monday during an update on the ongoing mapping exercise in Seychelles waters to determine the coverage and carbon storage capacity of Seychelles’ seagrass.

The project, which is being coordinated by the Seychelles Conservation and Climate Adaptation Trust (SeyCCAT), involves both national and international partners, including the Pew Charitable Trusts – which is funding the project, the University of Seychelles – Blue Economy Research Institute (BERI), University of Oxford, Deakin University and local non-governmental organisations such as the Island Conservation Society (ICS).

The project which aims at identifying locations, quantifying areas and determining the density and growth of each species of seagrass is part of the government’s commitment to protect and manage 100 percent of its seagrass meadows by 2030.

Dr Mortimer explained that among the main factors affecting seagrass in Seychelles include anchoring, and also fish traps that are being dragged on the sea bed.

In its updated Nationally Determined Contribution (NDC) submitted on July 30, 2021, Seychelles came up with a very ambitious climate targets and actions for the period 2021-2030.

The country is committed to reducing its economy wide absolute GHG emissions by 293.8 ktCO2e in 2030 (26.4%) compared to business-as-usual (BAU) scenario.

Mitigation and adaptation ambitions are well embedded in Seychelles’ updated NDC with a bold commitment focusing on its coastal wetlands; protecting 100 percent of its seagrass and mangroves ecosystems.

Seychelles will also establish a long-term monitoring programme for seagrass and mangrove ecosystems by 2025 and include the GHG sink of Seychelles’ blue carbon ecosystems within the National Greenhouse Gas Inventory by 2025.

The country commits to the implementation of its adopted Marine Spatial Plan and the effective management of the 30% marine protected areas within the Seychelles’ Exclusive Economic Zone (EEZ).

In the first phase of the project, researchers collected countrywide satellite images of the ocean. These images show the presence of seagrass, along with other ocean habitats, such as coral reefs.

Because cloud cover and water clarity can affect the quality of the satellite imagery, field data is also collected to differentiate the images.

The Seychelles Seagrass Mapping and Carbon Assessment Project will build the scientific baseline necessary to support the inclusion of seagrass protections into Seychelles’ NDC. Researchers on this project will fill key data gaps regarding seagrass distribution, extent, and soil carbon stock by drawing on advances in satellite remote sensing and field collections.

To better understand the location and extent of seagrass, researchers will collect satellite images of seagrass beds throughout the country. Images can be affected by cloud cover, water clarity, and ocean floor features, so local researchers will also collect field data to develop a validated map of seagrass distribution and extent.

To estimate seagrass carbon stocks, soil cores will be collected from meadows and analysed for their carbon content.

This carbon data, combined with the field-validated seagrass map, will provide for the first time a countrywide estimate of the seagrass carbon stock, and give policymakers in Seychelles the scientific baseline to include seagrass in the country’s NDC as a nature-based solution to climate change.

Roland Duval