Bees are among the main pollinators of many of the plants we eat, and as the demand for food grows, these key insects are under pressure. Farmers are growing crops at a rate that requires more pesticides, which have negative effects on insects, especially bee colonies.
Macadamia cultivation in South Africa has grown so rapidly that the country is now Australia’s main competitor for the title of the the world’s number one nut producer – with more than 700 growers in the country. Huge demand for macadamias, spurred by global health trends, has made South Africa the largest commercial planter in the world.
While pesticides to protect the value of the nuts have benefited farmers and the economy, they have damaged crop pollinators.
Inge Austin, coordinator of the beekeeping advocacy group in Mpumalanga, said: Daily Maverick The “macadamia bee value” was high, with a recent study showing an increase of up to 62% in nut set and quality where nut trees are pollinated by honey bees.
“Yes, bees are necessary for good pollination. The problem is when they use pesticides when the bees are there, during the blooming season,” Austin explains.
Schalk Schoeman, research and extension manager at Macadamia South Africa (SAMAC), said: Daily Maverick that while solitary bees were found in large numbers as pollinators, about 90% of macadamia pollination was done by honeybees.
Austin explained that both pesticides and fungicides negatively affect bees when applied during the blooming season. Non-seasonal rains, which have fallen a month earlier than usual in the Lowveld region in the past two years, have caused fungal infections in flowers, prompting farmers to use fungicides while the bees are still pollinating.
dr. Adriaan du Toit, Chairman of the Board of the South African Bee Industry Organization (SABIO), told Daily Maverick Pests have always been a problem in agriculture, but training and awareness initiatives aim to ensure the right chemicals are used at the right time.
“We work very closely with the macadamia association (Macadamias South Africa); we’re trying to get farmers to spray chemicals at night when the bees aren’t active,” says Du Toit. “We have had enormous success with this and many farmers are changing their working methods at their own expense. We make them realize that we need healthy bees.”
But it’s not just the time of spraying that affects bees, the type of pesticide is also a problem.
the pesticide neonicotinoid is banned in Europe due to its neurotoxic effect, but is still available and widely used in South Africa. The pesticide, which travels through a plant from the root, becomes a neurotoxin for bees within 10 days of use.
Schoeman said neonicotinoid was still legal in South Africa, but he suspected this could change in the future. Alternatives have been developed, but farmers with rough terrain, difficult for tractors to reach for alternative pesticide use, have few options.
“There are a lot of new pesticides available in South Africa, but the regulatory authorities are making it difficult for these products to go through the registration process. It can really take a few years for a chemical product to be registered,” says Schoeman.
“On the other hand, if you release natural products, you also have to register. Act 36 (Fertilisers, Farm Feeds, Seeds and Remedies Act 36 of 1947) requires that anything used in agriculture must undergo a rigorous research process.
“I don’t see a problem with that, the only problem I see is the time it can take. It can take five to seven years and I wish it was a little shorter. In farming, when things change, you have to be there and go with the change. You can’t react too slowly, because that will pull the competition floor away from us,” said Schoeman.
Austin said beekeepers understood that farmers should use pesticides on crops, but that it should be done in an environmentally sound manner without killing bees and other pollinators.
She added; “Macadamias are not the only crops harmful to honeybee health; there are several. But because there’s such tremendous growth of the macadamia industry in the country, it’s something that we’re really concerned about because they need bees so much, but our colonies often shrink after they’ve been on the macadamias. They don’t always die right away, but in the months that follow, you have a slow collapse; it’s like they never really recover.”
Du Toit said: “From both industries (beekeeping and macadamias) we try to educate farmers about the choice of pesticides because there are alternatives. But that takes time and is an ongoing effort.”
About a third of crops rely on pollinators for their flowers. Without them, crop production would decrease by about 5% in high-income countries and 8% in low- to middle-income countries, Our world in data has found.
Crops that rely heavily on bees for pollination include fruits such as apples, apricots, blueberries, cherries, mangoes, peaches, plums, pears and raspberries. Nuts such as almonds, cashews and colas, along with avocados, also rely heavily on pollinators. Kiwis, melons, pumpkins, watermelons, but also cocoa beans and Brazil nuts would lose about 90% of their yield without pollinators.
While spraying Doom on insects has become instinctive, 40% insect decline could spell disaster for humanity, as the earth’s ecology relies on insects to maintain processes that keep everything alive. The “windshield phenomenon” has proven that the decline in the number of insects on your windshield is an indicator of the decline in insect populations worldwide, has shown the decline in insects due to a number of factors.
“A rethinking of current agricultural practices, especially a serious reduction in pesticide use and its replacement with more sustainable, ecologically based practices, is urgently needed to slow down or reverse current trends, allow for the recovery of declining insect populations. and safeguard the vital ecosystem services they provide. In addition, effective remediation technologies need to be applied to clean polluted water in both agricultural and urban environments,” says an investigation conducted by scientists from Australia, Vietnam and China.
Because macadamia pollen is sticky and cannot be wind pollinated, the crop needs dispersal agents, such as bees.
Austin said: “As beekeepers, we don’t tell farmers, ‘Don’t spray.’ We say: ‘Spray the right things at the right time’. I would normally encourage them to check labels before spraying, avoid mixing chemicals unless directed, spray at night when bees and other pollinators are not active, look for areas where they should and not for spraying. When farmers spray blanket, it’s costly to the environment because you kill everything. You walk in some orchards and you don’t see the useful predators; the only thing alive is the vermin they are trying to kill!” DM/OBP