NAIROBI - Kenyan farmers say they are being forced to hand-pollinate their crops due to a decline in bee populations from pesticides. Kenya’s insect experts say the chemicals, meant to kill desert locusts and other pests, are killing off bees and other pollinating insects.
Kenyan farmer Samuel Nderitu says he made a good living from his crops for nearly a decade until 2019, when he noticed neighboring farmers spraying for pests.
His crop yields started dropping, says Nderitu, and he’s convinced it’s because the pesticides killed off pollinating insects like bees.
He has since been forced to hand-pollinate the plants.
"It has been quite successful — not 100% though because that’s not natural," he said. "The natural one is where the insects transfer the pollen from one plant to another; that's the most successful one. But now, because the pollinators are not there, we have to help in that process."
A 2019 desert locust invasion in east Africa forced Kenyan authorities and farmers into a massive spraying campaign to save their crops.
But Kenya’s International Center of Insect Physiology and Ecology says the unchecked use of pesticides is ironically killing off the pollinators on which the crops depend.
‘’The pesticides are affecting the health of the bees because the pesticides reduce immunity of bees," says Nelly Ngungu, a research scientist at the center. "Now, aggravating the effects of pesticides, and lack of forage because of climatic conditions, change in climate, all this they reduce the immunity of bees and can eventually lead to bee death and decline in population.’’
Kenya’s agricultural experts are researching pest control options that reduce chemical use.
Agricultural research professor Hamadi Boga says biological control — using predators that feed on pests — is one option.
"The biggest challenge is that biological control works exito, where exito means ‘in the lab.’ It works very well but when you take it to the field, because of rain and other environmental issues, sometimes it's not quite as perfect,” said Boga.
Biodiversity groups are also training Kenya’s farmers on how to repel pests without harmful chemicals that can kill pollinators. The national coordinator of the Kenya Biodiversity Coalition, Anne Maina, explains.
‘’We train them on what is called integrated pest management," she said. "For example, if you find that you have a particular pest that is giving you trouble or disease — how do you plant crops? For example, even in your kitchen garden, if you are growing vegetables, we encourage farmers to grow them with things like onions, pepper, or pilipili [chili peppers], and these are able to repel some of the pests."
Kenyan farmers like Nderitu hope to one day attract bees to their farms again.
Until then, he will have to do the pollinators’ work by hand.