Wildebeest, topi, zebra, and Thomson’s gazelle migrate into and occupy the Mara reserve, from the Serengeti plains to the south and Loita Plains in the pastoral ranches to the north-east, from July to October or later. Herds of all three species are also resident in the reserve.
All members of the “Big Five” (lion, leopard, elephant, Cape buffalo, black and white rhinos) are found here all year round. The population of black rhinos was fairly numerous until 1960, but it was severely depleted by poaching in the 1970s and early 1980s, dropping to a low of 15 individuals. Numbers have been slowly increasing, but the population was still only up to an estimated 23 in 1999. The Maasai Mara is the only protected area in Kenya with an indigenous black rhino population, unaffected by translocations, and due to its size, is able to support one of the largest populations in Africa.
Hippopotamuses and crocodiles are found in large groups in the Mara and Talek rivers. The plains between the Mara River and the Esoit Siria Escarpment are probably the best area for game viewing, in particular regarding lion and cheetah.
There are many large carnivores found here in the reserve. Lions are the most dominant and are found here in large numbers. Spotted hyenas are another abundant carnivore, and will often compete with lions for food. Leopards are found anywhere in the reserve where there are trees for them to escape to. Cheetahs are also found in high numbers on the open savanna, hunting gazelles and wildebeest. African wild dogs are quite rare here due to the widespread transmission of diseases like canine distemper and the heavy competition they face with lions, who can often decimate their populations. Their packs also roam around a lot and travel far distances throughout the plains, making it hard to track them. Smaller carnivores that don’t directly compete with the latter include African golden wolves, black-backed jackals, African striped weasels, caracals, servals, honey badgers, aardwolves, African wildcats, side-striped jackals, bat-eared foxes, zorillas, African civets, genets, several mongoose species, and otters.
Wildebeest are the dominant inhabitants of the Maasai Mara, and their numbers are estimated in the millions. Around July of each year, these animals migrate north from the Serengeti plains in search of fresh pasture, and return to the south around October. The Great Migration is one of the most impressive natural events worldwide, involving some 1,300,000 blue wildebeest, 500,000 Thomson’s gazelles, 97,000 topi, 18,000 common elands, and 200,000 Grant’s zebras.
Antelopes can be found, including Grant’s gazelles, impalas, duikers and Coke’s hartebeests. The plains are also home to the distinctive Masai giraffe. The large roan antelope and the nocturnal bat-eared fox, rarely present elsewhere in Kenya, can be seen within the reserve borders. More than 470 species of birds have been identified in the park, many of which are migrants, with almost 60 species being raptors. Birds that call this area home for at least part of the year include: vultures, marabou storks, secretary birds, hornbills, crowned cranes, ostriches, long-crested eagles, African pygmy-falcons and the lilac-breasted roller, which is the national bird of Kenya.