Why there are "too many" elephants in southern Africa, and not enough elsewhere?
Mon, 2012-04-30 17:05
A number of people have asked about an apparent paradox, that in most of Africa (East, West and Central Africa) elephants are apparently facing major threats from poaching and land use competition, while in southern Africa there are said to be "too many elephants". There are several factors coming together to create this divergence of viewpoints.
The facts seem to be that:
- Elephant numbers were very low across southern Africa and in most of the rest of the continent until fairly recently, being much reduced in numbers by hunting for ivory on an industrial scale in the 18th,19th and early 20th centuries. During the decades of elephant absence, tree and shrub species that they normally feed upon became widespread, in some cases coming to change the very nature and appearance of the ecosystems, and altering the animal communities along with the plants. When elephants were protected from hunting through the mid- to late 20th century, they increased in numbers across the region, and began to have effects on the vegetation that were alarming to some people. However, these relatively recent changes were in fact only returning many areas to the state they were in before elephants were extirpated by the ivory hunters.
- There has been less poaching in South Africa, Zimbabwe and Namibia in recent decades because they were all white-minority police states and they have kept a lot of that security infrastructure going. The economies of these countries have been stronger than those of many others in the continent and have been able to sustain, to a greater or lesser extent, the expenditure on wildlife protection established during the colonial and apartheid eras. The recent killings of rhinos in South Africa have been (and have had to be) high-tech operations to elude the anti-poaching systems; it is worth investing that level of inputs for rhino horn, which is much more valuable per kg than ivory, and the bad guys are not using the same methods to kill elephants (yet). There is probably more poaching in Zimbabwe now than the government admits and, in fact, no one really knows how many elephants there are there now in that country.
- Until fairly recently, wildlife authorities in SA, Zimbabwe and Namibia have managed their protected areas like cattle ranches, supplying artificial water in many places, which allowed elephants to cover all areas of the landscape and to spread their "impact" on trees everywhere as their numbers increased. In SA and Zim, they instituted culling during the 1960s, an intensive management approach that has never really been applied consistently in the rest of Africa. Culling was intended to minimize the impact managers were seeing when elephants foraged on vegetation, and to hold numbers at arbitrary levels that they called "carrying capacity" but which was really very far below any level that the elephants would reach through natural self-regulation and food-limited feedback. The whole approach was to try to keep conditions constant and unchanging. When culling was stopped in both countries around 1995, the elephant populations responded to the relatively great abundance of vegetation on offer by, of course, feeding on and changing the plant communities and enjoying rapid population increase, yet again.
- Land use zoning in SA and Zimbawe tends towards intensive agriculture across most of the countryside, with parks and reserves behind fences to protect commercial (and some subsistence) farmers. This leaves elephant populations locked inside the parks, with no possibility to disperse as numbers increase, unlike in East Africa (and Botswana and northern Namibia). Dispersal between different areas is one way that elephant populations regulate themselves, so if they are trapped inside fenced areas, they will inevitably increase to the point where they have noticeable impact on vegetation, and be considered "too many". This blocking of movements, and consequent increase in localised impact, has happened whenever elephants become fenced in, as in the Shimba Hills in Kenya.
- In Botswana, there has been less conflict over land use because of the low human population density in the elephant range in the north of the country and less poaching of elephants because of the relative lack of roads and commercial/ criminal networks for channeling ivory out of the country. As in South Africa, the elephant population was reduced by ivory hunting up to the early part of the 20th century and has been increasing in size, but also in range, since then. Changes in vegetation structure, and conflicts with farmers, are occurring in places from which elephants had been excluded in the past and which they are now re-occupying.
- In northwestern Namibia, the elephant populations in the desert lands and Etosha NP have been relatively stable and self-regulating, while those in the northeast, largely the Caprivi, are increasing as part of the transboundary population with Botswana.
- Management authorities in southern Africa are now catching up with ecological science, which recognises that ecosystems are heterogeneous and continuously changing. Although some remain unable to shake the concern that elephants will somehow "damage" ecosystems beyond repair, others – notably Rudi van Aarde and his colleagues – have noted the importance of meta-populations and landscape-level conservation planning. Cross-border conservation approaches are now taking place in a number of sites around the region, linking South Africa with Mozambique and Zimbabwe, and Namibia, Angola, Botswana, Zambia and Zimbabwe in an enormous Kavango-Zambezi Transfrontier Park.
- In much of the rest of Africa, elephant populations have also increased, but have in most cases been allowed to disperse more widely across landscapes. Populations in many areas were reduced a second time by the outbreak of ivory poaching of the 1970s-80s, and their numbers have not yet returned to previous levels, as land-use conflict is also on the increase from greatly expanded human populations. In the last few years, poaching for ivory, driven by demand from China, is emerging as a very serious threat once again.
- It is more than coincidence that the countries where claims of "over-population" are made are generally also those that press for relaxation of the ban on ivory sales. The definition of "surplus", whether or not there is an ecological rationale, in most cases serves the justification of consumptive, commercial use, and treats elephants as a commodity that should be exploited. Such thinking is reckless in the extreme, since elephant populations – with their low rates of increase – are uniquely prone to over-exploitation.
In summary, the changes seen in southern Africa which some have attributed to "too many elephants" have been the consequence of low poaching levels, coupled with human interference in ecosystem processes. Elephant numbers in most of the rest of Africa have either found their own level or have been reduced by ivory poachers, in the 1970s-80s and again – most dangerously – in recent years, while land use conversion has steadily eroded their habitat base.