MAKALALI – The elephant immuno-contraception programme that has been in place on the 25,000ha Makalali Private Nature Reserve for the last five years has received further funding from the Humane Society of the United States.
According to Audrey Delsink, in charge of the programme, "It has been a tremendous success and the population has stabilised." The study uses a vaccine that prevents elephant eggs from being fertilised through an immune reaction, rather than through sex hormones.
As the study mainly focuses on the behaviour of elephants, and "five years is a drop in the ocean of an elephant's life", the funding has been extended for a further five years. As well as herd demographics, the long-term use of the contraceptive in specific animals is also being monitored.
The herd has increased in size from 66 to 70, with the young cows that were prepubescent at the beginning of the study now having had calves. "The aim is not to have a zero percent population growth rate but to stabilise the population." Two female and two male calves have been born, with two of the new arrivals making their appearance shortly before Christmas.
In future, some cows will not receive the contraceptive and be allowed to reproduce, to allow the herd to have a more natural structure for the animal's social well being. This decision will be based on each animal's calving history, as the researchers intimately know all the animals in the herd.
At present 23 cows have been vaccinated for the study, none of which have calved. The cows are usually vaccinated in the winter months, and have been darted both from the air and on foot. Delsink is upbeat about the programme, saying that it has proved to be very successful with no behavioural complications to date as well as being cost effective.
She adds that the multifaceted approach that has been taken has allowed them to create models that can be used in different situations as they may occur in other reserves and populations.