Abraham Ekperusi, Ena Suarez

The Mangroves of the Gulf of Guinea - South is a regional ecosystem subgroup (level 4 unit of the IUCN Global Ecosystem Typology). It includes the Angolan, Gulf of Guinea Central, Gulf of Guinea Islands and Gulf of Guinea South marine ecoregions. The biota is characterized by six species of true mangroves with several associated mangrove species. The majority of the mangroves are found in the deltas within this region, and mainly restricted to coastal estuaries and lagoons along the North-East Atlantic coast. The Gulf of Guinea - South mangrove province mapped extent in 2020 was 12,956.4 km2, representing 8.8% of the global mangrove area. The main threats to mangroves are pollution from oil and gas exploration and production, overexploitation, urbanisation, coastal development, agriculture, land conversion, coastal flooding, sea-level rise and the spread of invasive alien species. Today, the Gulf of Guinea - South mangroves cover 33% less than our broad estimation for 1970. If this trend continues, the mangrove cover would decrease by a further 4.2% by 2070. Furthermore, under a high sea-level rise scenario (IPCC RCP8.5) ≈-26.3% of the Gulf of Guinea - South mangroves would be submerged by 2060. Moreover, 1.3% of the province’s mangrove ecosystem is undergoing degradation, with the potential to increase to 3.8% within a 50-year period, based on a vegetation index decay analysis. This is a conservative estimate given the lack of data to measure the true extent of environmental degradation impacting mangrove ecosystems in the province. Overall, the Gulf of Guinea - South mangrove ecosystem is assessed as Vulnerable (VU).