Building on recent biological surveys of ancient inselbergs in southern Malawi and northern Mozambique, which have led to the discovery and description of many species new to science, and overlapping centres of endemism across multiple taxa, Bayliss et al. (2024) propose a new ecoregion. They combine the findings from the biological surveys, and those endemic taxa with data on geology and climate. Subsequently, they propose the ‘South East Africa Montane Archipelago’ (SEAMA) as a distinct ecoregion of global biological importance.
The ecoregion would encompass 30 granitic inselbergs reaching > 1000 m above sea level, also known as “sky islands” hosting the largest (Mt Mabu) and smallest (Mt Lico) mid-elevation rainforests in southern Africa, as well as biologically unique montane grasslands. Endemic taxa include 127 plants, 45 vertebrates (amphibians, reptiles, birds, mammals) and 45 invertebrate species (butterflies, freshwater crabs), and two endemic genera of plants and reptiles.
The uniqueness of the region likely originates from repeated isolation of these mountains from the other African forests, combined with the great age and relative climate stability of the region.
Nearly all of the 30 mountains within the proposed ecoregion are threatened by fires and deforestation from charcoal production and shifting agriculture. The region experiences some of the highest deforestation rates in Africa, having lost 18% of its primary humid forest cover (on some sites up to 43%) since 2000. As the authors emphasise: “Urgently rectifying this situation, while addressing the resource needs of local communities, is a global priority for biodiversity conservation”.
Figure 1: Location and extent of the South East Africa Montane Archipelago (SEAMA) showing core sites
in red, and an outline boundary of the convex hull of the ecoregion (source: Bayliss et al. (2024))
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