Marine Biodiversity of Angola: Biogeography and Conservation

Abstract

Some major physical and oceanographic features of the Angolan marine system include a narrow continental shelf, the warm, southward flowing Angola Current, the plume of the Congo River in the north and the Angola-Benguela Front in the south. Depth, substrate types and latitude have been shown to account for species differences in demersal faunal assemblages including fish, crustaceans, and cephalopods. The extremely narrow shelf between Tômbwa (15°48′S) and Benguela (12°33′S) may serve as a barrier for the spreading of shelf-occurring species between the far south, which is influenced by the Angola-Benguela Front, and the equatorial waters of the central and northern areas. A similar pattern is evident for coastal and shallow-water species, including fishes, intertidal invertebrates and seaweeds, with species that have temperate affinities found in the far south and tropical species further to the north. In general the fauna and flora of the littoral zone appears to be consistent with a pattern of relatively low diversity of the shore and near-shore areas, that is characteristic of West Africa, but paucity of data for Angola may make such comparisons of diversity with other areas inappropriate at this stage. The Congo River delta and many features that are interspersed along the coast such as estuaries and associated floodplains, wetlands, lagoons, salt marshes and mangroves, support a rich suite of species, many of which are rare, endemic, migratory, and/or threatened, and provide important ecosystem services. While the ecological value of many areas or features is recognised, lack of any legal protection in the form of marine protected areas (MPAs) has been identified as one of the main challenges facing conservation and sustainable use of Angola's marine and coastal biodiversity and habitats, in the face of multiple threats. A current process to identify and describe ecologically or biologically significant marine areas (EBSAs) could provide a foundation for designating some MPAs in future.

Angola in Outline: Physiography, Climate and Patterns of Biodiversity

“…While a full synthesis and interpretation of the evolution of the country's fauna and flora awaits development (Cotterill 2010(Cotterill , 2015, recent workers have advanced towards consensus on the main patterns, as discussed in general terms for terrestrial biota in this chapter, for marine systems by Kirkman and Nsingi (2019) and Weir (2019), and for freshwater fishes by Skelton (2019) in other chapters of this volume. In brief, three marine ecoregions (Spalding et al 2007) are within or overlap with Angola's marine environment, namely the Guinea South, Angolan, and Namib Ecoregions, the first two of which belong to the tropical Gulf of Guinea biogeographical province whereas the latter is part of the Benguela biogeographical province (Kirkman and Nsingi 2019). Most of Angola's EEZ falls within the Benguela Current Large Marine Ecosystem, with only Cabinda in the far north being included in the Guinea Current Large Marine Ecosystem.…”

Angolan Biodiversity: Towards a Modern Synthesis

“…In Chap. 3 Kirkman and Nsingi (2019) synthesise the findings of recent multi-national research activities on the Benguela Current Large Marine Ecosystem project and other studies on Angola's coastal and marine systems. The long history of the evolution of Angola's biota is introduced by Mateus et al 2019in Chap.…”

Historical and contemporary range expansion of an invasive mussel, Semimytlius algosus, in Angola and Namibia despite data scarcity in an infrequently surveyed region

“…This expansion into Angola, thus, increased its range to 1005 km of shore from Moçâmedes to Walvis Bay (Table 1; Fig 1). This pattern of range expansion is a better reflection of the species' spread in the region in the late 1960s, which is notable for (1) the rapid rate of spread and (2) the breaching of the biogeographic boundary from the Namib to the Angolan ecoregions [41][42][43]. Additionally, some intertidal sites were known to have been extensively surveyed in the late 1960s yet, conspicuously, no reports of S. algosus were documented from these sites [9,10,12], suggesting that its distribution was patchy across its range and that it was absent from the southern coast of Namibia (Fig 1).…”