Misuse of pesticide is killing our bees
In his lecture at the World Agroforestry Centre last week, top insects expert Dr Dino Martins explained how loss of pollinators can wreck the economy. He spoke to Star’s John Muchangi
First, how did you develop interest in insects?
I grew up in Eldoret in a rural area. We didn’t have a television set and so after school I would go looking at insects. They are some of the most fascinating things. I went to Uasin Gishu High School and afterwards as I was waiting for a place at Moi University in 1994, I decided to sit the SAT (Scholastic Aptitude Test) exams. I did very well and was offered a scholarship at Indiana University, US. I returned to Kenya, worked for KWS and several other organisations. Afterwards I did my PhD at Harvard University. I’m still a research associate of the Museum of Comparative Zoology at Harvard, but right now my main affiliation is with Princeton University. I currently serve as the executive director of Mpala Research Centre in Laikipia.
You are arguably the leading expert on pollinators in Kenya. Why are they so important?
Pollinators are basically animals, insects usually, that serve as vehicles to help plants reproduce. They take pollen — the male part of the flower — to the stigma, the female part of the flower. We might see this as a very basic interaction but it’s very important for human beings because one in three bites of food is thanks to a pollinator. If you eat things like passion fruit, mangoes or if you grow different kinds of foods from seeds including carrots, onions, or coffee, they reproduce by #pollination.
What are some of the pollinators we have in Kenya?
Mostly, it’s insects and most of them are #bees. There are almost 20,000 different types of bees and in Kenya we have about 1,000 species. Other pollinators include flies, wasps and even some non-insects, for instance, bats and sun-birds play a role. Other insects include beetles, butterflies and moths.
Are these pollinators facing any threat?
Most of our pollinators are doing fine but in a few places we have problems with #pesticides. We have completed a survey of 500 different physical sites in Kenya to look at different crops. We studied coffee, tomato, French beans, watermelons and other things like butternuts and pumpkins. We found many farmers are not aware of the need to protect pollinators from insecticides. Insecticides are designed to kill pests, but you could also kill other useful insects like pollinators. The other problem is misuse of pesticides. The Kenyan market is flooded by a lot of pesticides including unregistered ones that are sneaked into the market. We have several cases where farmers are not getting good yields because of the poisoning of pollinators. We have managed to turn that around for crops like passion fruit and eggplant (Biringanya) to get almost a ten-fold increase in yields — just by managing the farm and the pollination better. For instance, you can create a habitat that attracts the pollinators toward the crop.
What exactly do we mean by misuse?
One can misuse pesticide in many ways. The key thing is, whenever you get a pesticide, you should read the label and check if it’s been licensed. You do not want to use a pesticide licensed for rice, on coffee, for example. Two, because of corruption or something, we have all these unlicensed pesticides. But we have been working closely with the regulators on that.
How bad is the situation?
It is very bad. Kenya is a very beautiful country but we are beginning to get some diseases we didn’t have. Cancer has many causes but one is exposure to chemicals. And it’s a very serious issue. If you have 10 farmers and one misuses a pesticide, it will affect everyone. Some of these chemicals have things we call organo-phosphates, or persistent organic polluters. They end up in the soil and water and last for decades, even for hundreds of years. We need to balance controlling pests and managing our health and the health of our farms. One of the questions I always ask farmers is: when you’re sick, who do you go to see? A doctor, and they diagnose you. But when the crops are sick, we immediately begin to spray chemicals on them. It may not even be a pest causing the problem on them. It may be a virus, a fungal disease in which you wouldn’t need to use a pesticide.
This knowledge needs to reach as many farmers as possible
Providing good information to farmers is a big part of this. In the past, farmers didn’t have good access to information. But now with social media and other platforms like iCow, people can have access to information. At Nature Kenya, through email we get 400 to 500 requests a month on pests. For instance, someone might say I found this caterpillar, can you advise me what to do. We are now setting a platform where, because the images are geo-referenced, we can easily identify the crop and insects and give farmers information in real time. We have to rethink extension services.
Your book Our Friends the Pollinators mentions that coffee relies on bees for pollination. How can farmers spray their coffee without affecting these useful insects?
Coffee can self #pollinate. But when it’s pollinated by insects, it produces a better quality coffee berry. If you want coffee to be graded as AA or AAA, the coffee beans have to be big, have good flavour and scent, and in every coffee berry there should be two full beans. That happens when enough pollen is deposited inside the stigma. So there’s a direct relationship between pollination and quality of crop. Pollinators are not just important in producing the yield, but they can influence the quality. And it turns out coffee studies in pollination in Kenya are still fairly new. We have some sites in western Kenya, northwest Kenya and central Kenya and in all of them, we found having wild insects around the crop is fine. We found up to 50 different species of bees — mostly honeybee — on the coffee as well as wasps and butterflies. There are some farmers in western Kenya getting very good prices for their coffee and a big percentage of this is because they are insect-pollinated.
United States lost more than 40 per cent of their honeybee colonies between April 2014 and April 2015, mostly to honeybee colony collapse disorder (CCD). What’s the cause of this?
There are multiple causes of the collapse but the evidence is very strong that it’s related tochanging environment, stress on the #bee due to changing climate and the farmland system. Youknown there they put bees in trucks and they drive them around to pollinate different crops. So the bees are under a lot of stress and it’s also a chance for diseases to spread, because when you put 10,000 hives together, it’s easier for diseases and parasites to spread between the hives. In Kenya, we take for granted pollination services. In New York, in a few months the apples will flower and it will cost farmers $120 (Sh12,000) per hive to rent pollination services. In California, the almonds are flowering, its $200 (Sh20,000) per hive for two or three weeks. That’s a big cost.
So what exactly has killed the pollinators there?
They have used so many pesticides so they have killed a lot of these natural insects. Two, they have destroyed all natural vegetation. They have changed the landscape. You are talking of huge mono-cultures that stretch for thousands of acres with no natural habitat. The key thing here is that bees, like you and I, need to feed from different kinds of things. The crop might only flower for one or two weeks a year but the bee has to live the entire year. It has to have other things and a habitat, like trees, plants in the hedges, wildflowers where it can go and feed. So the habitat must have diversity.
Do you encourage farmers to have hedges around their farms
You see, it’s a big tradition in Kenya. I was at a presentation where they said in the last 20 years, rural Kenyan farmers have planted more than 200,000km of hedgerows. This is impressive.
We are still debating whether to allow growing of genetically modified organisms in Kenya. Could GMOs kill pollinators?
It won’t affect the pollinators so much so much unless the pollen has also been engineered to contain a toxin. For example, one of the big GMOs coming are Bt cotton and Bt maize. Bt is a bacteria that occurs naturally and produces toxins naturally. Scientists have taken it and introduced it into a crop. So in theory is seems a good idea because you use less pesticide. But we must distinguish between high-tech GMO, or transgenics, where you take genes across species where it would not have naturally occurred, like bacteria to plants, fish into a tomato, versus advanced crop breeding using genetic techniques — I’m all in favor of that. The transgenics are problematic. For instance, the cowpeas (kunde) are grown all over the world but originated in Kenya and wild varieties are still available; farmers have also developed their own variety. If you introduce a GM cow-pea, the bees will visit these crops and spread it to the wild relatives and because Kenya is the centre of biodiversity of these crops, we could have a big impact. This is very dangerous because once you have released these genes there’s no going back. You can never undo it. We should weigh the costs and benefits of this technology. Kenya has a growing population wehave to grow more food, but more important, we should recognise we have a lot of biodiversity and we enough solutions. We do not need to go looking into this technology.
You won the Whitley Award twice. What does this mean to you?
In 2009, I won the Whitley award, which is presented to conservationists. Kenya is an amazing place because a number of Kenyans have won the award,. This is the first time they have presented it for insects. The Whitley Gold Award, which I won last year, is presented to a previous winner who has taken the work and scaled it up and made an impact. We are able to reach tens of thousands of farmers now. I’m very honoured to have received it.