The Great Wildebeest migration season is here again. The Great Wildebeest migration is the movement of vast numbers of wildebeest along with zebra, and smaller numbers of Grant's gazelle, Thomson's gazelle, eland and impala.
This spectacular assemblage of migrating mammals follows the rains in a clockwise loop from the southern part of Tanzania’s Serengeti National Park into Kenya’s Maasai Mara National Reserve, and back again. The river crossings that they must undertake to complete this annual cycle are dramatic events that attract thousands of tourists
The iconic wildlife migration is a vital ecological occurrence and a significant tourist attraction. A double room for two nights costs $3,850 (Sh412,000) at the Angama Mara lodge. There are 23 other facilities in the Masai Mara Reserve from where you can watch one of the last mass terrestrial movements of wildlife.
Five migratory wildebeest populations occur in: Greater Serengeti-Mara and the Greater Amboseli, ecosystem both of which are transboundary and straddle the Kenya-Tanzania border; Tarangire-Manyara ecosystem in Northern Tanzania; Mara-Loita ecosystem in South-western Kenya, and; Athi-Kaputiei located near Nairobi.
Going by recent studies on the dynamics of large mammal populations in the East Africa savanna, we will not enjoy the spectacle of wildebeest migration much longer. Wildebeest populations in the five ecosystems have declined by 72 to 95 per cent between 1977 and 2016.
The decline or near-collapse of large wildlife migrations is not unprecedented. For example, the Saiga antelope that migrated in the vast Eurasian steppe is now critically endangered. Similarly, the bison which is the largest surviving wild ungulate in North America once migrated through the Great Plains in tens of millions. Here at home the vast herds of Thomson’s gazelle and zebra once migrated through the Lake Nakuru-Elementaita ecosystem. Not anymore.
The cause of decline in migratory wildlife species is the savanna of East Africa, the Eurasian steppe and the Great Plains of North America are common. Rapid expansion in human population has created pressure through land use change converting huge swaths of wildlife territory to farmland, settlement and infrastructure corridors. Moreover, wanton hunting and poaching have accelerated the decline of wild animals, especially in the last century.
In the context of migration ecology, the consequences of cessation of movement raises major concerns about the capacity of fragmented and isolated patches of the East African savanna to maintain viable populations of large mammals in the next three to five decades to come.
Moreover, the flow of energy and nutrients associated with predation, scavenging and drowning of wildebeest plays an important role in structuring both terrestrial and aquatic systems. Studies show that wildebeest carcasses contribute over 1,000 tons of biomass into the Mara River, which comprises 107 tonnes of carbon, 25 tonnes of nitrogen and 13 tonnes of phosphorus.
Preserving habitat corridors that connect critical wildlife resources is critical to the survival of large mammal populations in the East African savanna. The Great Wildebeest migration must serve as a reminder of our solemn duty to nature and obligation to posterity.
Vice Provost at The Aga Khan University. Views expressed are the writer’s
