Researchers in northern Botswana have come up with a novel way to protect farmers’ crops from elephants: disco lights have proven to be effective in redirecting the great beasts from their path as they trample their way through to floodplains near the Chobe National Park.
Lines of flashing multi-coloured lights set up around farmers’ fields in the wildlife-rich Chobe Enclave have been shown to be highly effective at scaring off elephants.
The district lies close to the Chobe National Park and is home to 7,500 elephants. It's the site of a floodplain whose nutrient-rich soils are a draw to farmers. But their maize and sorghum fields are frequently destroyed by elephants on their way to the floodplain to graze and drink.
For two agricultural seasons between 2016 and 2018 the researchers, led by Australian scientist Tempe Adams, set up their lights at four villages. Half of the 18 study sites – the control fields – were unlit.
The lights were found to be effective at repelling elephants in 75 percent of 104 recorded elephant incursions, the researchers wrote in their study, published early this month in the journal Oryx.
“The likelihood of an elephant entering a crop field was significantly lower when lights were present compared to control fields,” the study says.
The lights, set up at 10-metre intervals on poles up to 1.7 metres high, constantly flash a different colour: red, green, amber, white, blue or yellow. During the study, the colour pattern was changed weekly to prevent elephants getting used to it.
Adams, who is research coordinator for Botswana-based NGO Elephants Without Borders, said her team hit upon the idea of testing strobe light barriers after discussions with farmers who had reported scaring off elephants at night with simple flashing torches.
“The idea of flashing is what we wanted to explore further,” Adams tells RFI. “It might be the association with people that makes the elephants fearful, or that it appears foreign or unfamiliar to them.
“The strobe effect for each light is random and looks very dramatic especially on a moonless night,” she adds.
Adams says the solar-powered disco lights are inexpensive and easy to use, and don’t even need to be turned on or off. They are the latest among several non-lethal elephant deterrents (dubbed EleSenses) that EWB promotes among communities.
These include solar-powered strands of electric rope, sensor alarms and an organic oil repellent, which elephants hate the taste and smell of.
Shrinking habitat for elephants throughout their range, and growing human populations, mean harmful interactions are increasing in Botswana and beyond.
Crop destruction and human deaths caused by elephants are used by the authorities in neighbouring Zimbabwe to justify calls to reduce its own elephant numbers.
Zimbabwe has an estimated 80,000 elephants compared to Botswana’s 125,000.
Flashing LED lights have been used to stop lions and other predators raiding cattle kraals in Kenya, Zambia and Zimbabwe. But this is thought to be the first time light barriers have been effectively used against elephants.
Pride in elephants
The light barriers have since been set up elsewhere in Chobe, and in Botswana's north-west Ngamiland district, Adams says. She hopes they can be used on the continent wherever there are negative interactions between elephants and people.
Botswana’s elephants are in the spotlight after around 400 were found dead from unknown causes between March and June, mostly near the Okavango Delta, another wildlife-rich area in the north of the country.
Tests have been done on samples taken from the carcasses but the results are still unknown. It's suspected the animals died from a viral or bacterial infection.
Adams said a countrywide survey carried out by EWB several years ago revealed that most people regarded elephants with pride, and "associated them with the natural heritage of the country".
She added: "Many farmers do not hate elephants, but rather they want to find successful ways that they can continue farming in wildlife areas."