Game Management In South Africa's Kruger National Park
JOHANNESBURG — Most people agree that elephants are wonderful animals, but would you want to own one? South Africa's Kruger National Park owns 8,400 and has for years been at wits end about what to do with them.
Although the free-ranging elephant herds are undoubtedly one of the park's greatest tourist attractions, the long-term damage they can cause to the environment has in the past endangered some of the other rare species that the park was set up to protect.
When their numbers grow, elephants push over trees and uproot shrubs, clearing the bush on which black rhinoceros and some rare antelope and birds depend for food and cover from predators.
Even though the Kruger National Park now covers an area the size of Connecticut, rampant growth in elephant population has ensured that, since the 1960s, the park's scientific management has considered that there were simply too many pachyderms to go around.
"The Kruger National Park is not an elephant reserve, it's a biodiversity reserve," explains Leo Braack, the park's director of science. "We've equal responsibility for all the other species, as well."
Their solution to this problem has proved highly controversial. Beginning in 1966, game rangers set out to control the population by culling up to 10 percent of the park's elephants each year, wiping out entire family groups with high-velocity military rifles. In the peak year of the cull, more than 800 elephants were shot.
Although South Africa's own elephant population is not in danger, international media coverage of the cull coincided with the attempt to impose a world ban on the ivory trade early this decade. Animal rights groups, particularly in the West, bitterly condemned the cull and began campaigning for a halt.
In 1995 the park authorities agreed to suspend the annual slaughter temporarily and seek other ways of solving the problem. Now, after three years of studies and international consultations, they think they may have found one: As far as possible, they plan to let nature take its course.
According to Dr. Braack, the real trouble with Kruger Park is not too many animals but not enough space. The introduction of boundary fences in 1959 meant that the resident populations could no longer follow traditional migration routes in search of water and grazing.
In order to rectify this, the park management drilled bore holes and built dams to provide dry season water holes. It also started the controlled burning of "blocks" of grassland and bush to prevent catastrophic fires wiping out large swathes of land for grazing and browsing.
The result is that however much the park may look like wilderness, it has for decades been partially protected from the region's roughly 10-year wet/dry cycles, and from longer term natural cycles whose existence is now suspected by scientists.
"What we discovered when we studied the various ecosystems is that together with fences and the problems of human encroachment, we've negated or dampened the natural fluctuations which are part of the natural system," Dr. Braack said.
The elephants, which have no natural predators and can eat both grass and leaves, have taken advantage of the guaranteed water supplies to thrive. Cape buffalo have also benefited from the artificial water holes and from the increased grazing created when the elephants destroy trees. Bush-loving species like the endangered roan antelope were beginning to pay the price for the increasing numbers of savanna grazers like wildebeest and zebra.
Spurred by the multiplying problems caused by over-management and the furor over culling, the park's management set in motion what Braack claims was "the most thorough, intensive, in-depth review that any conservation area on the continent has ever been subjected to."
The result was a revolutionary plan for managing the entire conservancy, and not just its populations of large herbivores. In the future, the park is to be divided into six major blocks, two small ones designed to protect special botanical environments and four larger blocks for the management of elephants.
At any one time, Braack says, two of the four main blocks will be designated as "high elephant impact zones." There the animals will be allowed to breed and prosper until a certain predetermined "threshold" of environmental damage has been reached, measured by their impact on selected plant species.
The thresholds for intervention will be considerably higher than the present level of damage at which southern African game rangers are tempted to reach for their elephant guns, Braack says. When these levels are reached, the management plans to begin removing elephants from the damaged blocks at a rate of 7 percent a year and allow the other two main conservation blocks to become "high impact" zones in their turn.
The management cycles could last as long as 60 to 70 years and are designed to reflect long-term population cycles detected in Africa's few remaining free-ranging elephant populations. The demarcation of the blocks will also be based on elephant criteria rather than human whim: Boundaries will be unfenced and are intended to reflect existing "clan boundaries" between the park's extended elephant families, lines which, some scientists say, the animals are reluctant to cross.
Equally important, the park also plans to remove at least half of its 300 artificial water holes and abandon its policy of block-burning bush to prevent major fires. From now on, animals will increasingly have to find their own water in the dry season, and game rangers will be called only to fight man-made accidental fires, while "natural" lightning fires will be allowed to burn unchecked, as they did before mankind arrived.
The conservationists say that this policy may well lead to lower numbers of some water-dependent species - like buffalo and elephant - but favor rarer species like the roan, which is happier when predator-infested water holes are far away.
According to Braack, the parks board has by no means ruled out the resumption of culling in the future, but hopes that the new system can at least greatly reduce the number of animals killed.
If possible, surplus animals will be transplanted to other conservation areas but this may not of itself solve the problem.