Grasslands of the World.pdf - Disasters and Conflicts - UNEP

J.M. SUTTIE
The changing face of pastoral systems in grass-dominated ecosystems of eastern Africa 25
Plate 2.1
Predator harvesting game. Cheetah among Harpachne schimperi – Athi plains,
Kenya.
and south-eastern Sudan, northern and western Tanzania and northwest Kenya,
the herbaceous layer of semi-deserts, bushlands and woodlands are dominated
by grasses, so they are included here as part of the “grass -dominated areas”
of eastern Africa because of their importance for livestock and wildlife . This
means that 75 percent of eastern Africa is dominated by either pure grasslands
or grasslands with varying amounts of woody vegetation within or above the
grass layer. Significant woodlands exist only in southern Sudan, Tanzania and
Eritrea , and in northern Uganda and western Ethiopia.
Eastern Africa is renowned for the diversity and number of its large grazing
and browsing wildlife (Plates 2.1, 2.2 and 2.3). A map of the density (number
per km 2 ) of species of medium and large mammals in eastern Africa was developed
by a simultaneous overlay of 281 individual species distribution maps (see
Figure 2.4, developed by Reid et al. (1998) based on analysis of databases from
IEA (1998)). The highest diversity of medium to large mammal species is found
in two large, contiguous patches: one in the Rift Valley of south-central Kenya
and central Tanzania , and the other in and east of the Ruwenzori Mountains
in southwestern Uganda and northern Rwanda. This is the richest diversity of
mammals of this size in all of Africa (Reid et al., 1998) and probably the world.
Most of Burundi, Kenya, Rwanda, Tanzania and Uganda support diverse
groups of large mammals, with fewer in most of Djibouti, Eritrea , Ethiopia and
Somalia . This map does not account for the rarity or endemism of large mammals,
which can be distributed quite differently from overall diversity.