American scientists determine that agricultural areas provide the best environment for honeybee performance
A recent study has determined that cropland benefits bees.
In a paper published in the Journal of Economic Entomology, University of Tennessee scientists, including lead author Mohamed Alburaki, compared beehives located in agricultural land to bee colonies in non-farming areas.
They found that bees that foraged on farmland thrived, and bees that foraged on non-farmland struggled.
“Our results indicate that the landscape’s composition significantly affected honeybee colony performance and development,” the paper’s abstract said.
“Colony weight and brood production were significantly greater in AG (agricultural) areas compared to the NAG (non-agricultural) area.”
Alburaki said in a University of Tennessee news release from early May that cropland provides more food for bees.
“Our study suggests that the benefits of better nutrition sources and nectar yields found in agricultural areas outweigh the risks of exposure to agricultural pesticides.”
The bees kept on non-agricultural land couldn’t find sufficient food, and two colonies in the experiment collapsed because of starvation, the news release said.
The findings might be of interest to the Ontario Beekeepers’ Association, which maintains that neonicotinoid insecticides, used as a seed treatment on crops such as corn, soybeans and canola, are a major threat to bee health.
In a statement released in March, the OBA encouraged the House of Commons agriculture committee to ban imidacloprid, a Bayer neonicotinoid.
The Pest Management Regulatory Agency has proposed phasing out imidacloprid because the insecticide may be hazardous to aquatic insects.
“The broad application of neonicotinoid pesticides like imidacloprid on field crops has been linked by PMRA to the decline in bee populations in Ontario,” the OBA said.
“Bees are exposed to these highly toxic, water-soluble insecticides via contact with dust from planting, from pollen gathered from target and adjacent crops.”
However, the PMRA, the U.S Environmental Protection Agency and the State of California released a joint report in January 2016 that said imidacloprid is not a threat to honeybees when used as a seed treatment.
“We did not have positive findings of risk for the seed treatment uses we assessed,” the EPA said at the time.
“Residue levels in pollen and nectar appear below the threshold for effects on honeybee colonies.”
The University of Tennessee scientists found pesticide residues in bee pollen, including imidacloprid, but at concentrations significantly below lethal levels for honeybees.
The researchers concluded that exposure to pesticides from agricultural land didn’t compromise bee colony productivity.
“We train agricultural producers on careful selection and conscientious application of pesticides to reduce bee exposure,” said Scott Stewart, an integrated pest management specialist at the university.
“But it’s becoming more clear that the influences of varroa mite and food availability are more important factors in honeybee health than agricultural pesticides.”