The days of culling elephants in Kruger to control numbers belong to the past. Instead the park is favouring more natural methods of control. By Glynis O’Hara
There will be no further culling of elephants in the Kruger National Park for population control. So says Dr Sam Ferreira, SANParks’ large mammal ecologist. That’s because the new, ‘natural’ methods of managing them have severely curtailed the population growth rate, bringing it down to just 2%, from a high of 6,5% when culling was stopped in 1994.
The current elephant population is estimated at around 16,900, said Dr Ferreira, based on the last count in 2012. It was 8,000 in 1994. However, without the new, more natural methods of control, the population would have been over 25,000 by now, if the 6,5% increase rate had continued at the time when culling stopped.
The new approach to manage the impacts that elephants have on various conservation values is a more natural one, largely through limiting access to waterholes. Over two-thirds of them were closed after 2003, starting in the drier, northern areas. As elephants moved away from newly closed boreholes, the landscape and vegetation got respite from elephant use.
“We’re restoring natural patterns,” Dr Ferreira explains. “We’ve closed boreholes and we’re removing some dams, although that’s a much bigger operation. We’ve also dropped fences between ourselves and Mozambique in the north and private reserves in the west, allowing more spatial range.
As expected, a typical natural process unfolded – with less easily available water, more calves and elderly elephants died and the birth rate went down. (Kruger’s last major drought was in 1992/3, so the impact of fewer waterholes during drought is still to be seen.)
An elephant cow, pregnant for 22 months, could in the best circumstances have a calf every three years, says Dr Ferreira. But now, with the water restrictions, elephants are giving birth every 4.2 to 4.5 years. “It’s a classic population response.” Cows have to walk further to get to water and food and it takes its toll on body condition, hence reducing the rate of conception. Calves suckle up to three years when they start to get their tusks. After that, they have to walk to water and food, like the rest of the herd.
None of this means Kruger is littered with the bodies of dead calves, Dr Ferrreira hastens to explain. “One calf dying irregularly can set back a herd by four years,” he says.
For the scientists, observing the impact of borehole closure and the changes in elephant reproduction rates takes time. “An elephant generation is 12 to 15 years and we have to monitor behaviour and impacts over the years.”
This is an extract of an article by Glynis O’Hara for Conservation Action Trust.