Zimbabwe Ecological Conservation: Assessing Effects of Urban Development and Drought on Tree Health to Protect White-Backed Vulture Nesting Sites in Zimbabwe

Despite its crucial role in the sub-Saharan African ecosystem, the white-backed vulture (Gyps africanus) faces extinction due to the increased mortality rates of nesting trees caused by drought and elephant damage. During droughts, African elephants (Loxodonta africana) cause increased damage around waterholes, leading our partners – Connected Conservation Trust and Victoria Falls Wildlife Trust – to investigate the connection between waterholes and the damage to white-backed vulture nesting trees. We used imagery from Landsat 5, Landsat 8, and Landsat 9 to assess vegetation health and landscape change from 1994 to 2024, through Normalized Difference Vegetation Index (NDVI) assessments and land use and landcover (LULC) classification, to examine the impacts of elephant aggression and climatic conditions. We examined these changes in the context of waterhole locations, nesting sites, and environmental factors to provide insight into their relationships. Within an 8-kilometer radius around waterholes, vegetation health declined since 2020, suggesting extensive elephant damage following a major drought. In 2024, we found that 95% of vulture nesting sites were within 8 kilometers of a water source, suggesting that the nesting sites will be increasingly impacted by elephants and other wildlife traffic. Overall, vegetation health did not decline significantly; however, vegetation types are becoming sparser, with 43% of woodlands converted to less tree-dense types. As vultures prefer nesting in tall trees on the border of open land, these land use changes could limit potential nesting sites. While NDVI and LULC from Landsat imagery were feasible methods for this study, the image resolution limited the detail possible to detect. Nevertheless, our findings demonstrate the need for further conservation efforts.