The price of habitat: in southern Africa, increasing conflict between elephants and humans is raising painful questions about cohabitation on a crowded planet.

• Author: Sugal, Cheri
• Position: Includes related article on synthetic ivory keyboards

An excruciating conflict is under way in southern Africa - not a war between rival tribes, but a territorial conflict between two species: Homo sapiens, which is rapidly expanding its claims on the land, and Loxodonta africana, the African elephant, which needs large expanses of land by nature, and which can become dangerous when crowded.

The trouble stems from the fact that both humans and elephants are capable of running roughshod over the earth. People destroy 850,000 hectares of forest - an area half the size of Israel or Kuwait - in southern Africa every year, much of it for agricultural expansion into the elephants' habitat. Elephants, in turn, sometimes trample farm crops and kill people who have moved into close proximity. In the band of wildlife-rich but economically poor countries that stretches across the southern part of the continent from Angola to Mozambique, ecologists are asking how elephants and people - and other competing populations - can successfully exist in the same environment. Many are now convinced that the only way they can manage that is to find ways to use local wildlife - elephants included - as a sustainable economic resource. Just how to do that has become a matter of intense debate and painful decisions.

In this debate, two camps have become vociferous. One has taken a stand for strict preservation of habitat - setting aside and protecting tracts of land and allowing nature to take its course. The other takes the view that human development has already passed the point where such preservation can suffice. It holds that because human activity has already altered many natural ecosystems to the extent that they are no longer capable of self-regulating, we can only protect nature from here on by managing it ourselves - by taking active measures to counter the effects of such no-longer-natural phenomena as the crowding of elephant populations into parks too small to support them.

Strict preservation of habitat is the most simple way, and sometimes the only way, of effectively saving species, especially endemic species - those adapted to life within a particular biological niche. But setting aside enough habitat to preserve a large population of nomadic animals such as elephants, which move over migratory routes covering hundreds of kilometers, and every day consume more than a quarter ton of solid food each, is almost impossible. Most wildlife sanctuaries are simply not large enough to support elephant populations, and farmers or villagers living on the periphery are highly vulnerable to what happens when the giant animals don't stay inside their boundaries. In 1995, for example, villagers living near Zambia's Bangweulu Swamp wildlife preserve nearly starved after elephants from the park began trampling farmers and destroying crops.

On the other hand, the view that it's too late not to use human intervention is based on observations that once-stable elephant populations are being dangerously destabilized - in some places decimated, in others increased to the point that they begin destroying their own habitats.

In the past, the elephants' gargantuan eating habits have played a key role in sub-Saharan ecology, helping both to control their own population and to sustain the diversity of other wildlife. In the savanna, elephants dig water holes, which other species use as well. In wooded areas, they push over trees and shrubs while browsing for food (they subsist largely on saplings, bark, and leaves in the rainy season), but this also helps to regenerate the same vegetation they destroy. Many acacia trees, for example, will not regenerate in the shade of mature trees. When the old acacias are destroyed, new trees get started. Meanwhile, the downed vegetation helps promote fires, which convert woodland to grassland (creating habitat for such grazing animals as zebras), and the elephants migrate away in search of more forage.

This ecological dynamic helped to control population by making elephants work extremely hard to survive - subjecting them to a regimen that not all could survive. For example, there is a 25,000-square-kilometer ecosystem called the Serengeti-Mara, a grassland along the border of Kenya and Tanzania, that prior to the middle of this century had been a woodland. The woodlands reverted to grasslands as they were consumed and overrun by elephants. In past centuries, the elephants would then have moved on. As they ate their way across the landscape, some of them would have found themselves stranded by their own appetites, too far from any newly regenerated forage, and would have died of starvation. But that also meant that they had ranged far enough to let the land they had left behind them regenerate.

In recent decades, however, this cycle has been interrupted. Elephants confined to smaller ranges by the expansion of human development can quickly exceed their range capacity. Their sudden overcrowding is exacerbated by the fact that parks and refuges now offer a constant supply of water - greatly stabilizing the historically uncertain habitat and virtually ensuring uninterrupted reproduction. Because elephants are known to keep breeding as long as their food and water supply is adequate, this can set them up for rapid population increases - which sooner or later reach unsustainable levels.

Under these conditions, hungry herds may be compelled to migrate into areas where they are not wanted or where the woodland has not yet had time to regenerate. In the Mara reserve of the Serengeti-Mara ecosystem, emigrations from the nearby Serengeti, where elephants were being slaughtered by poachers in the late 1970s and early 1980s, arrested the ancient process of regeneration; overcrowded, the region no longer produces new woodlands, and its capability to serve as elephant habitat has been ravaged - adding further impetus to the animals' restless search.

War, which has severely torn Africa's human societies in recent decades, has also torn its environment - and has escalated elephant migrations, sometimes turning whole herds into environmental refugees. In South Africa's Kruger National Park, between 1960 and 1970, elephant populations increased from 1,000 to 8,821, primarily as a result of immigration by animals fleeing gunfire in neighboring Mozambique. While the problem of in-migration was remedied by enclosing the 2-million-hectare park with a fence, the elephant population continued to outgrow its capacity. Kruger can sustainably support only one elephant for every 300 hectares, or a total of 7,000 to 7,500 individuals. Yet, since 1974, the population has risen at a rate of 7 percent per year - an annual addition of 500 elephants that the park cannot support.

Wildlife management proponents worry that Africa's elephant population, if left unchecked, will greatly overshoot the available resources and enter an irreversible decline. They cite a case in the late 1960s, when elephant populations in and around Kenya's Tsavo National Park had reached about 40,000 - a number that virtually every scientist who looked at the problem agreed could not be supported by the ecosystem. Conservationists and wildlife experts argued that 3,000 elephants needed to be culled - deliberately "harvested" - to stabilize the population. Preservationists replied that nature should be allowed to take its course. In an outcome that was to characterize the debate that has continued since, the preservationists prevailed. The area was subsequently hit by severe drought, and at least 9,000 elephants died of starvation. Several hundred rhino died as well - victims of a rampage in which the desperate elephants destroyed not only their own vegetation but the rhinos'.

The African elephant is running out of space among the 100 million people now living in the southern region of the continent. In the 1980s, the expansion of human activity reduced the amount of range available for elephants on the continent from 7.3 million square kilometers to 5.9 million - a 20 percent decline in just one decade. Africa's protected areas (a total of 3.9 million square kilometers of the elephants' range, according to the World Conservation Union), are only a fragment of the wildlands their inhabitants once roamed. Clearly, what's happening here isn't working for the elephants, and it's not working for people either. The question now is whether there's a way to resolve the conflict that can restore stability to elephant populations while serving as a benefit, rather than a threat, to human communities.

When man encounters elephant

To a strict preservationist, and perhaps especially to someone who has not actually experienced what is happening in southern Africa, an elephant may be seen as one of nature's most noble and majestic creatures - a gentle giant that has played large roles in human history and mythology. But to a Zimbabwean or Namibian villager, the damage that can occur when elephants break out of their shrinking confines - whether because of overpopulation or because of growing pressure from poaching, logging, farming, or war - can be traumatic. Elephants have been known to raid crops and grainaries in search of forage and water, uproot...