The Queen Elizabeth National Park includes more than half the Uganda coastline of the great lakes Edward and George, as well as the 20-mile-long Kazinga Channel which connects the two. Large schools of hippo are present throughout the length of this coast, and they graze inland each night to a steadily increasing degree. The land area of the park is some 760 square miles, of which at the most 400 can be utilized by the hippo. A careful and conservative estimate gives the population of these animals at not less than 14,000, so that each is restricted to a maximum of 16 acres of grazing. In fact, of course, the hippos graze as near as possible to the waters in which they spend the day, making the actual concentration near the lake shore much higher than this. And there is a large number of other grass-eating animals competing for the same grazing: buffalo, kob, waterbuck and other ungulates as well as elephants, all in large numbers. These, however, are not tied to one particular habitat as are the hippos, and are therefore less likely to be the cause of the overgrazing and beginnings of erosion which are evident.
Queen Elizabeth National Park: Uganda The Hippopotamus Problem and Experiment