GUELPH A new Ontario study says neonic-treated canola seed has no impact on bees.
The study, conducted by researchers at the University of Guelph and Dalhousie University, looked the impact of clothianidin-treated canola seed on honeybee colony health, development, and overwintering success. Clothianidin is one of three neonics approved for use by Health Canada.
During the summer of 2012, the researchers placed 40 colonies of bees in 10 fields of canola throughout southwest Ontario, including five fields in Waterloo, two in Wellington, and one each in Brant, Oxford, and Wentworth. Each field had five acres of canola, and the bees were placed when 25 per cent or more of canola had bloomed to ensure bees would not go off-site to gather food.
The researchers specifically found fields where no other canola was being grown nearby, and fields where there were no neonic-planted crops the previous year.
“Overall, colonies were vigorous during and after the exposure period, and we found no effects of exposure to clothianidin seed-treated canola on any endpoint measures,” reads the Oct. 30 report. “Overwintering success did not differ significantly between treatment and control hives, and was similar to overwintering colony loss rates reported for the winter of 20122013 for beekeepers in Ontario and Canada. Our results suggest that exposure to canola grown from seed treated with clothianidin poses low risk to honey bees.”
The study was funded by Bayer CropScience, but the researchers noted that the companys personnel had no role in collecting or interpreting field and honeybee colony data, or in writing the report.