THIRTY five elephant in the Kruger Park have been darted from the air with sedatives, checked with an ultra-sound machine to ensure they are not pregnant, and given a hefty dose of the pachyderm pill in a novel experiment designed to test whether animal contraception can minimise the need for culling the Kruger National Park’s elephant population.
The experiment, funded by the Humane Society of the United States, involves research into two types of contraception. The first method, known as “immuno-contraception,” requires the cows to be injected with a vaccine derived from proteins harvested from pigs’ ovaries. The vaccine provokes the formation of antibodies in the elephant that binds its ovaries and prevents them from being penetrated by sperm.
The second method requires the cow to be immobilised so that implants of oestrogen, which work according to the same principles as the contraceptive pill used by women, can be surgically implanted into the animals. So far 25 cows have been vaccinated and another 10 implanted with the pill.
The aim of the experiment is to determine whether this kind of contraception works and, if so, whether it has an adverse effect on the long-term fertility and behaviour of the elephants.
Initial computer modelling suggests that at least 2 300 adult cows will need to be under treatment at any one time in order to stabilise the Kruger National Park populpation … The costs involved in doing so for 2 300 elephants at this stage appears to be prohibitive.
Although the research project is still in early experimental stages, it drew widespread criticism at the elephant policy indaba hosted by the National Parks Board this week. A number of wildlife organisations complained the project involved an extravagant expense at a time when rural people could benefit from revenues and products derived from elephants.
“Africa is a protein-poor continent. We’re trying to grow cattle and crops. All the world has cattle and crops! But elephants are something the world wants. They want to see them, and they want their products, and we’ve got them. But what do we do. We reduce productivity through contraception. It makes no sense,” said Jon Hutton, project manager of the Africa Resources Trust, in an article criticising the experiment.
“Elephants can provide both income, through the sale of products and hunting licences, and much-needed protein for communities bordering national parks. The same economic activities can also fund the upkeep of those parks.”
The parks board, however, insists that its relatively small experiment does not mean it has given up the right to use culling as a population control method. “The current state of this technology suggests that even if contraception works in elephants, it will not be a viable option for controlling larger elephant populations,” says an official statement. “However, should the research show that contraception can be achieved in elephants, it will offer a useful option for limiting small populations.”
But Anthony Hall-Martin, director of research and development for the National Parks Board, admitted at the indaba that Kruger’s population could be allowed to rise as high as 25 000 if the policies of other conservationists in Africa are followed.
Hall-Martin noted that Kruger’s management had based its culling policy on observations that elephant moved into new grazing land once their herds exceeded 1,2 animals per square kilometre of rangeland. In parts of Tanzania and Zimbabwe, where ecological conditions were similar to those in Kruger, conservationists had established the terrain could support 2,7 elephants per square kilometre.
David Barrit, from the International Fund for Animal Welfare, said he welcomed the board’s decision to review the scientific status of its policies and to open the debate on how to handle Kruger’s elephants to the public.
Other animal rights groups said Hall- Martin’s admission vindicated their claims that the old policy of shooting a few hundred elephants a year to keep the population of Kruger at around 7 500 had not been necessary.