Increasing temperatures, changing rainfall patterns and massive demographic change are all altering the savannahs of East Africa. Already, we know that savannah birds are shifting their distributions over scales of 100s of kilometres, following shifts in rainfall patterns. However, the impacts of changed rainfall regimes on these species are unlikely to be direct, but are rather mediated by changes in the availability of food resources. So how might changes in temperature and rainfall interact with changes in grazing and fire regimes to generate the ecological change we see? Using case studies from Tanzania's Serengeti and Tarangire ecosystems Dr. Colin Beale will review the mechanisms that may underpin recent changes in savannah ecology, highlighting working hypotheses that link rainfall and fire, via plant growth and nutrient acquisition to insect herbivores and ultimately bird distribution and diversity.
Claire Van Wyk - claire.vanwyk@uct.ac.za