Notes from the Field : A Visit to Kenya's Masai Mara with Peregrine Fund Researchers

Post written by, Ralph Buij, Wageningen University and Research Centre, Netherlands

For someone like myself, who has studied raptors in savannas of western Africa the rich grasslands of East Africa’s Masai Mara are truly something else. Rolling grasslands as far as the eye stretches, with meandering rivers bordered by lush riparian forests – a rare sight in the densely inhabited west. The Mara’s grasslands support some of the highest density of ungulates in the world even when the wildebeest are absent, with a suit of carnivores and vultures depending on them for food. It did not take me long to accept Munir Virani’s invitation to join him and his friend and teammate Anthony Tira on their raptor nest survey in this most famous of Kenya’s protected areas.

Our mission was to track down all raptor nests, with an emphasis on the larger species, especially vultures; Critically Endangered White-backed vultures breed colonially and often in tall sycamore fig trees in the riparian vegetation, while equally threatened Lappet-faced and White-headed vultures occupy the Boscia and Faedherbia trees that dot the wide-open grasslands. Now is their peak breeding season and many were on eggs or had small nestlings, awaiting the return of the wildebeests to this part of the grassy plains from July. The riverine forests are also favoured breeding haunts for Martial and Tawny Eagles, Bateleurs, Grey Kestrels, African Goshawks, rare African Hawk Eagles and elusive Western Banded Snake Eagles. All these are under pressure from tourist facilities expanding in their breeding habitat, which is one of the reasons for Munir and Anthony to map their nests: a no-go buffer zone around nests would be needed to avoid disturbance and loss of some of East Africa’s most important breeding sites for threatened raptors. 

Earlier that week Munir had already shown me Hell’s Gate NP, where he studied his Augur Buzzards, and Lake Naivasha’s Fish Eagles. The Fish Eagles are treated to fish thrown from boats, so tourists can enjoy close-up views of Fish Eagles swooping down to the water surface. We had some truly magnificent sightings and it’s a splendid way to obtain ring readings from photos. In the Mara, a dead hyena attracted Tawny Eagles, White-backed, a single Rüppell’s, White-headed, Hooded and Lappet-faced vultures, with Bateleurs patrolling the vicinity. Other highlights were several Martial Eagles including a fledgling calling for food near its nest, a late Honey Buzzard, a pair of African Hawk Eagles and two Western Banded Snake Eagles. But the real treat for me were those nesting vultures, over 60 White-backed, seven Lappet-faced and a single White-headed vulture pair. Incubating their eggs as if immune to the catastrophe that has hit their kind. Relicts of a vanishing and underappreciated community of magical large soaring birds, already exterminated in far too many regions of the continent.

One cannot fail to be impressed by the beauty of these expansive grasslands with their abundance of topi, giraffe, impala, Thomson's and Grant's gazelle, waterbuck, elephant, and large herds of buffalo. We saw lions and cheetahs chasing warthogs and a leopard with a 1-year old cub on a fresh reedbuck kill several meters from our car. All of these are under pressure from encroaching human populations around the reserve, where cultivation, growing livestock numbers and retaliatory killing of predators also impacts wildlife populations inside the reserve. The breeding vultures we saw are an integral part of the Mara ecosystem but most at risk of vanishing with these developments. The true loss this entails for humankind is potentially huge and their ramifications through cascading impacts on other species, including the iconic large carnivores, little understood. The Peregrine Fund’s Mara Raptor Project aims to shed more light on these and other matters. Through their efforts, Munir and Anthony’s are setting the stage for effective conservation of the Mara’s raptors, and by extension this priceless ecosystem, for future generations.