Elephants (Loxodonta africana) and hippopotamuses (Hippopotamus amphibius) are major architects of habitats. Where they occur at a natural density elephants can change woodland to grassland savannah and in forests play an important role in seed dispersal and maintenance of many species of tree. Hippos on the other hand create grazing lawns around lakes and rivers and through trampling damage can increase woody cover where overgrazing takes place. They also destroy wetland when at high densities such as fringing papyrus swamps to lakes. As a result both species need to be monitored and sometimes managed to avoid major changes to ecosystems and the subsequent impacts to other species. This is necessary because many protected areas, particularly in the Albertine Rift, have become islands surrounded by agriculture and there are no options for species to move elsewhere when densities become very high.
The WCS Albertine Rift Program has been studying these two species in the Greater Virunga Landscape as well as monitoring elephant populations in the Kahuzi Biega National Park.