Picky baboons develop a taste for pinot noir (but merlot just won't do)

Baboons, it seems, prefer pinot noir. They also like a nice chardonnay. Largely undeterred by electric fences, hundreds of wild baboons in South Africa's prized winelands are feasting on ripe, succulent grapes, forcing winemakers to use noisemakers and rubber snakes to try to drive them off during this harvest season.

"The poor baboons are driven to distraction," said Justin O'Riain, who works in the Baboon Research Unit of the University of Cape Town. "As far as baboons are concerned, the combination of starch and sugar is very attractive – and that's your basic grape."

Growers say the picky primates are partial to sweet pinot noir grapes, adding to the winemakers' woe, for pinot noir sells for more than the average merlot or cabernet sauvignon.

"They choose the nicest bunches, and you will see the ones they leave on the ground. If you taste them, they are sour," said Francois van Vuuren, farm manager at La Terra de Luc vineyards, 50 miles east of Cape Town. "They eat the sweetest ones and leave the rest."

Baboons have raided South Africa's vineyards in the past, but farmers say this year is worse than previous ones because the primates have lost their usual foraging areas due to wildfires and ongoing expansion of grape-growing areas. Out of a 12-tonne harvest, about 5 per cent goes to waste at La Terra de Luc because of the baboons. And in the Constantia wine-producing area alone, up to £23,000 worth of the crop has been lost annually in previous years, according to the Baboon Research Unit.

Sometimes the baboons get an alcohol kick – by feasting on discarded grape skins that have fermented in the sun. After gobbling up the skins, the animals stumble around before sleeping it off in a shady spot.

During harvest season from January to March, winemakers put up serious frontline defences. Some try to scare off the baboons by blowing into vuvuzelas , horns that are often used by South Africa's football fans.

Electric fencing often doesn't work because baboons can dig underneath it or swing above it from trees to get to the vineyards. They also test the fence for weak spots. If they're shocked, they'll scream, but they'll probably return the next day, says Mr O'Riain.

Sakkie Lourens, manager of Cabrière farm, has found one ruse that seems to work – rubber snakes. "I put them all over where the vines are, and since then, I haven't seen a single baboon," he said.

The Baboon Research Unit is pioneering a hi-tech approach in which a collar with a sensor is placed on a member of a baboon troop. When the collar passes a particular point, an "incoming baboon" text message is sent to a mobile phone, prompting someone to race to the fence and defend the vineyard.

Mr O'Riain doesn't think the problem will go away because vineyards are expanding into the lower slopes of the mountains, the baboons' traditional foraging grounds. "Where there's a mountain, there's a baboon," he said. "As we take up more and more of their land, the conflict increases."