IUCN Red List of Ecosystems. Sandy Beaches & Dunes of the West African Transition

Abstract The ‘Sandy Beaches and Dunes of the West African Transition’ form a regional ecosystem subgroup along the West African coast. It had a mapped extent of 584 km² in 2022, with a width ranging from 0.012 km to 4.796 km, and stretching over approximately 1321 km. This ecosystem subgroup extends along the shores of Mauritania, The Gambia and Senegal. This ecosystem frequently experiences coastal hazards at varying scales, sometimes beyond its resilience threshold. Prominent among the hazards are erosion (-0.1 m/yr to -20.62m/yr) and submergence with regional sea-level rise (SLR) rates of ≈4 mm/yr. Anthropogenic factors such as coastal infrastructure development & urbanisation, sand mining, upstream river management and subsequent coastal land subsidence are also resulting in deterioration of the ecosystem. In 2022, the sandy beach and dune ecosystem covers approximately 22% less than in 1986. The ecosystem area will decrease a further 32 % by 2072, should the current trend continue. Using a precautionary approach, the adoption of a very high SLR scenario (IPCC SSP5-8.5) indicated that about 15% of the ecosystem would be submerged by 2072. However, the inherent uncertainties in the landward delineation of the ecosystem, dune extents especially, and the Multi-Error Removed Improved Terrain Digital Elevation Model (MERIT DEM), may have resulted in the underestimation of the spatial distribution and the projected inundated extents respectively. Overall, the status of the sandy beach and dune ecosystem of the West African Transition is Vulnerable (VU).