6 October 2011, by Tamera Jones
Locking up bins and enticing South Africa's Cape Peninsula baboons away from built-up areas by giving them corn kernels could ease clashes between them and local residents, say scientists.
But they found that feeding the baboons only works as a short-term solution. What's really needed to solve the conflict is simply to make sure that lockable baboon-proof bins are used all the time. This would make urban areas much less attractive to the primates.
'As long as there's food around, there's no reason for them to leave town,' says Dr Andrew King from the Royal Veterinary College in London, co-author of a study published in the International Journal of Primatology. 'But solving the baboon problem is more about managing people, which is challenging.'
Cape Peninsula residents have been in conflict with the region's baboons for years. As the human population has expanded over the years, the tension has escalated. At the peak of the problem, animals were shot, run over, and electrocuted on electric fences. 'The baboons are surrounded by urban areas, they're closed in, and are completely isolated from other baboon populations, so there was little chance of movement in or out of the population,' says King.
'As long as there's food around, there's no reason for them to leave town.'
Dr Andrew King from the Royal Veterinary College in London
So, the decision was made to protect them. Indeed the Cape Peninsula is the only place in South Africa where the baboons are protected. Now, with so much waste food around, the population is thriving. 'It's got to the point where the authorities may have to intervene and manage this population,' adds King.
To the west of Simon's Town, on the east coast of the Cape Peninsula, a troop of around 21 baboons regularly raids three hotspots – Happy Valley home, the Navy barracks and the Signal School – because they have big kitchens and lots of waste food.
Typically – when council funds allow – monitors shoo the primates away by whistling and shouting. This approach works, but when money is tight and there are no monitors, the baboons come straight back.
After studying chacma baboons in the Namib Desert, King wondered if his work could be used to solve the region's baboon problem. In Namibia, he discovered that alpha males tend to lead the troop to food sources. If he and his University of Cape Town colleagues could tempt the Simon's Town troop's alpha male away from the built-up area, maybe the rest of the troop would follow.
First of all, they studied when the Cape baboons ate and slept, and worked out the troop's home range. Once they'd done this they knew where to scatter the corn kernels. 'The food we offered had to be high-quality, and within their home range for this to work. After all, they can get donuts in town,' says Bentley Kaplan from the University of Cape Town, lead author of the study.
After scattering kernels just before sunrise, they watched the baboons' movements.
They found that the troop's time spent in urban areas dropped from 40 per cent to 30 per cent. This showed that the corn kernels weren't enough to persuade the baboons to stop raiding the urban area; although they did improve the situation.
But after the researchers restricted access to the bins and kitchens in the three hotspots using wire mesh, this figure went right down to 12 per cent, and the baboons spent a lot less time raiding.
'It's a case of follow my leader: where the alpha male goes, the rest of the troop follows,' King explains.
While enticing the baboons away from urban areas by using corn kernels might work, King says this shouldn't be a long-term solution. 'There's a risk that overuse of natural vegetation could change the fragile ecosystem in this biodiversity hotspot, and if low-ranking troop members continue to miss out on food, there's a possibility they won't bother to follow their leader anymore.'
'Ultimately, the answer is to make sure bins are locked up and all other human food sources are secured as well,' he adds.
The local authorities provide residents with baboon-proof bins, which work when they're used. 'The problem is that as soon as the baboons disappear, people forget to lock their bins,' says King.
He says the next step is to take these findings to the people of the Cape Peninsula. 'We need a public debate.'