The shortage of bees in agricultural areas limits the supply of some food crops, a new US study has shown, suggesting that pollinator reductions could have serious implications for global food security.
Wild bee species, such as bumblebees, suffer from loss of flowering habitat, the use of toxic pesticides and, increasingly, the climate crisis. Meanwhile, controlled honey bees are exposed to beekeepers, but are still susceptible to disease, which is a concern that three-quarters of the world̵7;s food crops dependent on pollinators may fail due to a shortage of bees.
A new study confirms some of these fears.
Of the seven crops studied in 13 states across America, five showed that a lack of bees hindered the amount of food that could be grown, including apples, blueberries and cherries. A coalition of scientists from the United States, Canada and Sweden surveyed 131 field crops for beekeeping activity and crop numbers.
“Crops that got more bees got a much better harvest,” said Rachel Winfrey, an ecology and pollination expert at Rutgers University who was the senior author of an article published by the Royal Society. “I was surprised, I didn’t expect them to be limited to that extent.”
The researchers found that wild local bees introduced a surprisingly large amount of pollination, despite the fact that they worked in intensively cultivated areas, largely devoid of vegetation that supports them. Wild bees are often more efficient pollinators than honey bees, but studies have shown that several species are in sharp decline. For example, the rusty bumblebee was the first bee to be listed as an endangered species in the United States in 2017 after falling 87% in the previous two decades.
American agriculture is backed by bees, breeding wildly and moving around the country’s hives to meet the growing need for crop pollination.
Almonds, one of the two crops that have not been affected by bee shortages, are mostly grown in California, where most hives in the United States carry trucks for mass almond pollination each year.
The United States is at the forefront of divergent trends around the world – as agriculture becomes more intensive to increase large volumes to feed a growing global population, tactics such as smoothing wild meadows, spraying large numbers of insecticides and planting monoculture fields single crops harm bee populations, which are crucial for crop pollination.
According to the Food and Agriculture Organization of the United Nations, the number of crop products dependent on insects and other pollinators has increased by 300% over the past 50 years. Lack of contamination can lead to some fruits and vegetables becoming thinner and more expensive, leading to nutrient deficiencies in diets. However, basic foods such as rice, wheat and corn will not be affected as they are pollinated by wind.
“Honey bee colonies are weaker than before, and wild bees are probably declining by a lot,” Winfrey said. “Agriculture is becoming more intensive and there are fewer bees, so at some point pollination will be limited. Even if the bees were healthy, you run the risk of relying so heavily on one species of bee. It is assumed that the parasites will target the same species that we have in these monoculture crops.
The document encourages farmers to better understand the optimal amount of pollination needed to increase crop yields, as well as to check that the level of pesticides and fertilizers applied to the fields is appropriate.
“The trends we are seeing now are giving us food security concerns,” Winfrey said. “Right now we are not in a complete crisis, but the trends are not going in the right direction. Our research shows that this is not a problem in 10 or 20 years – it is happening now. “