The most famous of Serengeti's predators is the lion. Predators have been more thoroughly studied than anything else in the Serengeti, and lions have been studied more intently than any other predator, with research dating since the 1960's. This research has been entirely behavioral, and little is known of other aspects of carnivore ecology. In fact, there are not even good estimates of population sizes of the large carnivores. We do know that the lion population on the Serengeti Plains dropped by about a third during the 1990's due to disease that is believed to have spread into the park from surrounding domesticated animals.
Lions are indisputably a formidable animal due to their size, their numbers, and their behavior.
Little evokes Africa in my mind more than lying in bed at night in the Serengeti and hearing the coughing roar of lions roaming outside the house or, even more alarming, my tent, sometimes so close that the sound penetrates my body and seems to make my skeleton vibrate. But no night sound makes the hair stand up on the back of my neck quite like the voice of a hyena. It was believed before Serengeti research that hyenas were scavengers, but research here has shown that they are awesome predators, assembling at dusk in large packs that hunt with impressive efficiency. Another night stalker is the leopard, which is probably seen more easily in the Serengeti than any other place where they are not baited by hanging a carcass in a tree to attract them. Here they are frequently seen during the daytime relaxing in trees along the rivers of the Seronera Valley.