for National Geographic News
South African Air Force fighter pilots, and many a civilian aviator, too, would have been saddened by the recent death of Mpho, the cheetah. They would also have been grateful to the fleet-footed predator for nearly a decade of service patrolling a remote air base, chasing warthogs and other small game off the runways in one of the wilder parts of South Africa.
Mpho, meaning "gift" in the indigenous seSotho language, was stationed at Hoedspruit Air Base in the northeast of South Africa, near the Kruger National Park, a region still teeming with wild animals even outside the park's fences.
In the days of apartheid and southern Africa's anti-colonial wars Hoedspruit served as an advance air base at which Mirage jet fighters were stationed. After South Africa's political settlement in the early nineties, it started doubling as a civilian airport called Eastgate, resulting in passenger jets calling.
From the outset, warthogs were a frequent menace on the runways. But smaller antelope like impala were also a hazard to the aircraft. Animals wandering onto the runway while aircraft were landing or taking off could easily cause a disaster.
The air base is on a 4,900-acre (2,000-hectare) piece of land which, apart from landing strips and small buildings, remains wild bush country. It also has substantial numbers of game inside its fence. And making the problem worse is the preference of grazers like warthogs and impala for the short, mowed grass next to the runways, from where they can all too easily dart into the path of speeding aircraft.
Major Philip Oosthuizen, head of the base's environmental services, says the airport administration first tried to shoot the game. But this made the problem worse: "It proved impossible to exterminate them. The warthog simply hid in holes and the antelope in the bush where they kept breeding, and more kept coming into the base area through holes the warthog dug under the periphery fence.
"Rather than driving them off, the shooting succeeded only in scattering them and leaving those remaining skittish and even less manageable.
"When left alone, the warthog move about in groups and the impala in herds. This makes them easy to spot and to be driven away from the danger areas. With the hunting, they scattered and started dashing singly over the runways. It just made it all so much more dangerous," says Oosthuizen.
It was then that he came up with the idea of resorting to nature's way, by introducing cheetahs to keep the small-game numbers down without scattering the groupings in which they move about.
Capable of reaching speeds of 60 to 70 miles per hour (97 to 113 kilometers per hour), the cheetah (Acinonyx jubatus) is the fastest of the land mammals. The big cat typically preys on smaller antelope, warthogs, hares, and game birdsthe very animals that range freely on the Hoedspruit property.
Oosthuizen first introduced a pair of female cheetahs to the air basebut this presented an unexpected new hazard.
Unlike the males, which move about in bachelor groups of two or three and who like to hunt together, female cheetahs move about and hunt singly. The trouble is that they are then unable to eat their whole catch by themselves, and the remains entice vultures, which are an even bigger threat to aircraft.