Migratory Mayhem

The migration season in the Maasai MaraSerengeti region in Africa has begun earlier than usual this year, due to the destruction of habitats

- Maina Waruru

THE MAASAI Mara-Serengeti region, spanning across the borders of Kenya and Tanzania, has been a theatre to the great wildebeest migration for thousands of years. An estimated 1.5 million wildebeest or gnus, zebras and gazelles as well as many species of large African herbivores migrate across the Mara river anticipating rains and in the pursuit of fresh pastures and water.

This year, however, the migration of animals from the Serengeti National Reserve in Tanzania to the Maasai Mara National Reserve in Kenya began earlier than usual— in June. The migration usually starts in July and ends in October. Tourist operators are scheduling the African safaris much earlier. In eastern and southern Africa, fragmentation of habitat has occurred along with the decline in the abundance and geographic range of animals. For example, in northern Tanzania, there has been a gradual loss of connectivity between seasonal ranges available to migratory wildebeest. This has led to fluctuations in the abundance of animals.

Such changes in migratory patterns are expected to increase with the loss of availability of water and food. Recent studies have found that a number of factors, including climate change, human activity, growing human population, change in land use patterns, infrastructural development, and recently, the profusion of invasive alien plant species are causing widespread disruption in migratory patterns.

Zebras already face obstacles in migration routes. A study by German researchers in Botswana, published in the Proceedings of the Royal Society B recently, found that zebras rely on memory to follow migration routes to reach fresh vegetation. “This memory risks making inaccurate predictions of vegetation and water abundance as seasons are changing,” Chloe Bracis of the Senckenberg Biodiversity and Climate Research Centre, Frankfurt, told