The Kruger National Park and the Mapungubwe National Park and Word Heritage Site has an elephant problem: There are too many!
The elephant overpopulation has been a major issue in southern Africa since the mid-20th century and the continual debate in South Africa over a solution to “the elephant problem” has been prominent enough to merit international news coverage.
As early as 1968 a NY Times headline proclaimed “Growth of Elephant herd Taxes South African national park”. This is nothing compared to coverage within South Africa, especially within the scientific community. Since 1960, South African researchers have produced more than 150 scientific articles related to elephant biology and management. The majority of these articles have been published within the past ten years reflecting the growth of global interest in biodiversity conservation.
As elsewhere in Africa, South African elephants were exploited for their ivory for more than 10 000 years. Though laws against exterminating Wildlife introduced in South Africa beginning in the 1650’s, by 1890 the population had merely wiped out. In the 20th century, lower establishment of national parks and game reserves, fencing of conservation areas, and more aggressive anti-poaching efforts allowed South African Elephant populations to grow even as they continued to decline elsewhere. In 2006, the elephant population in Kruger was estimated at 12 427 with a national rate increase of about 27% from 2002 to 2008. The Mapungubwe National Park in 2012, counted 1 293. The present population size is considered to be slightly over 1 300. The size of the elephant population has become a big problem for both the savanna ecosystem where the elephants live and for the humans who live nearby or visit the parks.
By examining the story of elephant overpopulation in South Africa we can gain insight into the way conservation sciences works today and begin to understand the unique role the humans play in the biosphere. The elephant problem is rooted in the power these large animals have to shape their environment. At 3 tons for adult females and 6 tons for adult males, Loxodanta africana, the African elephant, shapes its environment simply by moving.
They consume about 60 kg of vegetation per day (and gouge deep into tree trunks with their tusks, uproot trees up to 60 cm in diameter and dig into the ground with tusks and feet to find food or water holes in dry river beds. The discarded material alone alters a range of ecosystem characteristics. Elephants also disperse seeds and contribute to nutrient cycling. Biomass of elephants correlates negatively with biomass of other browsers (who feed mainly on trees and shrubs) and grazers (who feed on grass) with a weaker relationship for the latter group.
Reductions in bred populations which live in the trees shrubs, and grasses that the elephants destroy, also correlate with elephant overpopulation. It is well-established that elephant overpopulation is destructive to biodiversity.
Biodiversity is necessary for proper ecosystem function and for the production of ecosystem services such as gas regulation, climate regulation, water supply and treatment, pollination, biological control and food production, among others.
However, the effects of elephant overpopulation, extend well beyond biodiversity destruction. Just as elephants compete with plants, birds, and herbivores for space and resources, so too they compete with human neighbours, sometimes with disastrous consequences. Elephants can destroy crops, raid food stores, damage infrastructure, and kill livestock and cause injury and loss of human life. Broken fences can also lead to spread of infection between wildlife and livestock with the biggest concern for foot-and-mouth disease.
What is to be done about the elephant problem if anything? This is the question that Southern African scientists and policymakers have spent a half-century trying to solve. There are four main options: Translocation; Contraception; Culling, and Spatial redistribution through transfrontier parks and other means. Each has its costs and benefits, and some are more compelling than others. Elephants have been shown to have complex social structures, excellent temporal and spatial awareness and highly developed emotions and behaviours not unlike seen in humans. For example elephants appear to mourn their dead and suffer from an analogous to post-Traumatic Stress Disorder.
Translocation is one of the older solutions to the problem of elephant overpopulation but it is stressful to animals and can cause behaviour problems, especially if family groups are disrupted.
Elephant contraception is currently an area of active research in South Africa. Though contraception alone will not reduce population numbers in the short term, it may have the potential to prevent further increase and reduce numbers on the long term. By far the most controversial solution for reducing elephant’s numbers is culling - killing elephants.
The dispute over culling includes both moral and practical questions. The most obvious ethical issue is the harm done to the elephants that are killed. The most humane culling practises require well - trained workers and expensive equipment, such as helicopters. Yet culling can also generate resources and income from elephant meat and skin. But on the long term, culling would have to be maintained indefinitely at a rate above the population growth, unless combined with another method such as contraception. Overpopulation is a by-product of human activity. The question then becomes whether humans have a responsibility to correct the problem. It is up to us to decide how we would like to shape our environment in the years to come.
Though elephant distribution is determined by numerous factors - water, landscape food availability, population density, and social structures - they are trumped by fences. Because fences have such power to determine elephant distribution and have led to an elephant population that cannot be supported by the resources within the confined space, they may hold the answer to the elephant problem. Already boundaries between Kruger and the Limpopo National Park in Mozambique and Mapungubwe National Park, Botswana and Zimbabwe have been opened.
But these options of a trans-border park is as much of a political decision as it is an ecological one.