Ecosystem health and human wealth – A comparison of sub-Saharan African Large Marine Ecosystems

Abstract

Sub-optimal levels of ocean health were determined for four sub-Saharan African Large Marine Ecosystems (LMEs), based on Global Environmental Facility (GEF) Transboundary Waters Assessment Program (TWAP) assessments. Various ecosystem health and pollution indices that were considered reflect coastal degradation that is ubiquitous in many areas of these LMEs, such as pollution, eutrophication, and widespread loss and modification of coastal habitats including mangroves, estuaries, lagoons, and corals. The Guinea Current LME (GCLME), which has the highest coastal population of the four LMEs, was found to have the greatest cumulative human impact and the highest nutrient and pollution levels, associated with agricultural, industrial and domestic wastes. A large percentage of the GCLME's coastal population is rural, and with fishing as a major livelihood and a high dependence on fish protein, the LME is most at risk of overexploitation. A highly inequitable distribution of economic development and wealth was evident in each LME, but the socio-economic vulnerability of the GCLME and Agulhas Current LME (ACLME) are considered to be the highest of the four LMEs, because of the high numbers of poor people among their coastal populations. Based on the Human Development Index that takes into account factors such as life expectancy, education and income, the Somali Coastal Current LME (SCCLME) was the most vulnerable of the four LMEs to external events such as disease or extreme climate related events, due to less than perfect human health, education and income levels. The international scale of key stressors in the LMEs, including climate change, commercial shipping and others, emphasizes the need for global and transboundary cooperation in management and mitigation. This requires effective transboundary governance, but in this regard the GCLME, ACLME and SCCLME are lagging behind the Benguela Current LME (BCLME), where the establishment of the Benguela Current Commission and subsequent signing of the Benguela Current Convention have facilitated high-level engagement by the governments, and provided for full integration across transboundary issues in the component EEZs. Continued and enhanced monitoring will be essential for assessing and understanding impacts of threats and the effectiveness of conservation efforts, and initiation of new in situ monitoring should be considered in combination with models, where applicable.