Wildebeest, commonly called "[G 20 / gnus]," are the dominant [G 22 / herbivores] in the Serengeti-Mara region of [M 001 / East Africa]. Their numbers make up two thirds of the nearly two and a half million mammals that inhabit an [G 14 / ecosystem] about the size of the state of Vermont.
[G 19 / Flora], predator, prey, and scavenger all play vital roles in maintaining the precarious balance in this dynamic system. But it is the [N 001 / migration] of 1.4 million nomadic wildebeest that defines the Serengeti-Mara ecosystem.
As they move through the different regions of the ecosystem on their annual 1,000-mile trek, they provide food for the nomadic [L2 101 / predators and scavengers] that follow them and the resident predators that anticipate their return from year to year. They also stimulate new grass growth through [L2 102 / extensive grazing] and fertilizing, which enhances the food supply for smaller herbivores that follow.
Not all the wildebeest in this region migrate. There are [L2 103 / resident herds] that live in areas which have a stable source of food and water year around thus eliminating the need to migrate; however, their numbers are few. They account for only about one percent of the wildebeest population.
Through the eons, that wildebeest have [L2 104 / V004 / seasonally grazed] in the region, their numbers have ebbed and flowed in response to disease and variations in rainfall. Modern history dates to the late 1800s when a disease called [L2 105 / rinderpest] was introduced to the region, decimating the [G 41 / ruminant] populations - largely the wildebeest, [I 002 / buffalo] and cattle.
For 70 years, periodic outbreaks ravaged these groups until rinderpest was eradicated in the early sixties. Since then, the [L2 106 / wildebeest population] has increased six-fold and is currently estimated to be 1.4 million.
