As the rains retreat northwards, the increasingly arid landscape poses a problem for the Great Rift’s wild inhabitants, and is a particular problem for the African buffalo. Each buffalo needs to drink 34 litres a day, as dry grass is difficult to digest. As the grazing close to the river is used up, they face a longer and longer daily trek between their feeding grounds and watering places. Buffalos can smell water from a long way off and follow established trails through the bush, which lead to favourite drinking spots. As the buffalos drink, fluttering oxpeckers get a chance to remove ticks and other parasites from their faces, but this is the only time they will tolerate sharp beaks picking around sensitive eyes and ears.