“If we don’t keep some of our female lions on contraceptives, the population grows rapidly out of our control and when we have too many lions, they eat more herbivores, which are also in small numbers because we’re one of the smaller parks.”
Those were the words of Addo Elephant National Park resident vet Dr Dave Zimmerman during a visit by SA National Parks veterinarians to Addo on Wednesday and Thursday, when they gave contraception to some of the park’s lionesses.
“We don’t do it to the same [lioness] every time,” Zimmerman said.
“The contraception we use lasts for about two to three years before it wears off and if you don’t top it up then they start cycling and conceive again.”
The contraception procedure is a population control method to maintain the park’s predator to herbivore ratio.
The procedure is performed on lionesses every two to three years to prevent them from procreating and exceeding Addo’s ideal lion population of less than 20, he said.
The elephant park houses seven lions in its main camp and five in its Nyathi section.
Outdated battery-operated collars on some of the lions were changed and some hyenas were relocated to a game reserve in the Northern Cape.
“We have four adult females and only one will be off contraceptive while the other three are on,” Zimmerman said.
“After one female reproduces one cub, she’ll be put back on a contraceptive.”
He said contraception was a better population control method than swapping with other nature reserves as there was a low demand for lions.
“Contraception does have its side effects like weight gain as it does on human beings.
“The problem is that there isn’t a high demand for lions from a conservation perspective.
“Yes, the lion population across Africa has been reduced but the human population has also exploded and pressures on natural areas are immense,” he said.
On Wednesday afternoon, the vets, who were accompanied by rangers in training, sedated four-year-old Jack to remove his collar, check his heart rate and draw blood samples for tests.
More lions were sedated to have their collars changed and put on contraceptives yesterday.
“We haven’t replaced Jack’s collar because he is one of the more visible lions in the park, so he doesn’t really need a collar as much as the others who are harder to find,” Zimmerman said.
Collars help track lions in the park and identify them if they escape.
The procedure also served as a training opportunity for SANParks rangers to better their chances of being authorised to handle problem animals and perform procedures in emergencies.
Park manager Nick de Goede said the relocation of 10 hyenas bought on auction last year was part of population management.
“Last year after a census was done we realised that, due to the impact hyenas have on prey, there were too many of them, so we decided to put some on auction and managed to sell 10 of them to the same buyer for a total of R215,000,” De Goede said.
- Day visitors will have free entry into SANParks from November 16 to 20 during the annual SANParks Week usually held in September.