The comeback of Kenya's elephant population is a huge conservation success story, as well as a huge problem for the country's farmers. But scientists have found a new ally in the struggle to keep elephants from trampling crops: honeybees.

Like many animals, elephants are afraid of bees. So scientists recruited farmers in northern Kenya to test different types of barriers and found that fences made of beehives were far more effective than traditional thorn-bush fences at thwarting nighttime elephant raids.

"The farmers in the area are desperate for a solution," said zoologist Lucy King of the University of Oxford, lead author of a study on beehive fences in the July 5 African Journal of Ecology. "They haven't had much help from anyone else. They were very open-minded about this crazy idea."

Elephants were nearly wiped out in Kenya by poachers during the 1970s and 80s. Then in 1989, the U.N. Convention on International Trade in Endangered Species banned all international ivory trade, and since then, Kenya's elephant population has nearly doubled. But the country's human population has grown even faster, going from 12 million people in 1970 to nearly 40 million today. Natural land is becoming more scarce, but allowing elephants to migrate between preserves safely will be key to their survival.

"[The elephants] are coming back into a world where there are so many more people," King said. "They are finding buildings, roads, schools and farms across their normal migration routes."

And when elephants encounter farmland, crops get eaten and trampled, and the situation can turn deadly. Elephants often leave farms with spear and gunshot wounds. Each year a few dozen people and few dozen elephants die during nighttime raids. And so far, barriers built to protect farms have not been successful.

"All of the earlier attempts, which rely on capsicum chili pepper, on burning or on thorn trees, they really haven’t worked all that well," said conservation biologist Dave Balfour, who has worked extensively with elephants in the Hluhluwe-Imfolozi Game Reserve.

Elephants have been known to leave acacia trees, their normal food source, untouched if there is a beehive in the branches. So in a previous series of experiments, King played recorded hive sounds for herds of elephants. The animals ran away from the buzzing, rumbling alarm calls to each other. It was from this work that she got her crazy beehive fence idea.

To test if bees could help farmers, King and her colleagues from Save the Elephants chose an area known for human-elephant clashes. The land is farmed by the Turkana community, a tribe that moved into the region about 30 years ago. Before that the area was wild, unclaimed bush where elephants could migrate unimpeded.

The scientists and farmers built beehive fences to protect the cropland and found that the buzzing, stinging insects were very effective guards. Out of 45 attempted farm invasions, over two years of monitoring, elephants made it through sections protected by thorn-bush barriers 31 times, but only one elephant – a very determined bull – broke through a section of beehive fencing.

"Everyone was surprised at how well it worked," said King. "We most of all I think."

The beehive fences brought the farmers an added perk – extra income from honey sales. An average farmer in the area lives essentially hand-to-mouth on the equivalent of $20-30 a month. An extra $15-20 from honey every few months lets farmers make investment purchases, such as new clothes, or a large bag of maize or sugar. With a strong financial motivation, the farmers keep the fences well-maintained.

"That's probably what is keeping the project going," King said. The team recently released a beehive fence construction manual for interested farmers.

"This is one of the more encouraging bits of work we’ve seen lately in how to control elephants in an open landscape," Balfour said.

Image: Lucy King.

See Also:

Citation: “Beehive fences as effective deterrents for crop-raiding elephants: ﬁeld trials in northern Kenya.” By Lucy King. African Journal of Ecology, July 5, 2011.