How effective are the protected areas of East Africa?

Protected areas are the cornerstone of in situ conservation and their effective management is critical for maintaining biodiversity in the long term. In East Africa (Burundi, Kenya, Rwanda, Tanzania and Uganda) there are 1,776 protected areas (including 186 “strict” protected areas with IUCN management categories I through IV) covering more than 27% of its terrestrial area. Here we document the extent to which East African protected areas encompass ecoregions and endemic terrestrial vertebrate taxa, and using new land conversion data derived from medium to high spatial resolution satellite images, we assess how they have been encroached upon by agriculture and other land use. We find that East African protected areas cover 86% of ecoregions well (>10% threshold of ecoregion representativeness set by the Convention on Biological Diversity's Aichi Target 11), some very well (>90% - Rwenzori-Virunga montane moorlands and East African montane moorlands). In contrast, Masai xeric grasslands and shrublands, Somali Acacia-Commiphora bushlands and thickets, and Southern Swahili coastal forests and woodlands are poorly represented. Protected areas cover at least 10% of the distribution of 256 of 303 East African endemic and near-endemic terrestrial vertebrate species (the latter defined here as having 90% or more of their range in East Africa). However, 37% of these species' ranges do not have at least 10% coverage by strict PAs and only 26% of endemic species have at least half of their range covered by PAs. Encouragingly, we find that only 6.8% of East African protected areas has been converted to agriculture or other human use since gazettement. Only 1.6% of strict protected areas have been converted providing very strong evidence that strict protection is the most enduring way of safeguarding habitat. Keywords: Biodiversity, Conservation prioritization, Effectiveness, Endemic species, National parks, Representativenes