WSU trial finds “very low risks,” while England study shows bee species suffer from the pesticide.
Bee health studies examine neonicotinoid risks
TJ Mullinax // Aug 19, 2016
A honeybee in a Prosser, Wash., cherry orchard on March 3, 2015. (TJ Mullinax/Good Fruit Grower)
Two different bee health studies have popped up in the news concerning neonicotinoid pesticides and whether they have an impact on the health of bees.
Washington State University released details from a one-year trial collecting samples of bee bread, which includes bee pollen combined with bee secretions, from non-wild honeybees around Washington to measure detectible levels of neonicotinoid residues.
Although neonicotinoid insecticide residues were detectable, the amounts were substantially smaller than levels shown in other studies to not have effects on honeybee colonies. The WSU researchers referenced 13 studies to identify no observable adverse effect concentrations for bee populations, which they used to perform a risk assessment based on detected residues.
“Based on residues we found in apiaries around Washington state, our results suggest no risk of harmful effects in rural and urban landscapes and arguably very low risks from exposure in agricultural landscapes,” said Allan Felsot, WSU Tri-Cities.
Another study by a United Kingdom research council, the Center for Ecology and Hydrology, was published linking wild bee population declines to neonicotinoid insecticide use.
The study, conducted over 18 years across England, shows several bee species suffer from the pesticide.
But this new work suggests, for the first time, that the detrimental impacts seen in the lab can be linked to large scale population extinctions of wild bees, especially for those species of bees that spend longer foraging on oilseed rape.
“The negative effects that have been reported previously do scale up to long-term, large-scale multi-species impacts that are harmful,” said Dr. Nick Isaac, a co-author of the new paper. “Neonicotinoids are harmful, we can be very confident about that and our mean correlation is three times more negative for foragers than for non-foragers.”
TJ Mullinax joined Good Fruit Grower as digital producer and photojournalist in 2013. He photographs and edits visual stories for the print magazine and online publishing spaces. Along with editorial production, TJ develops and maintains the magazine’s digital products. -- Follow the author: Phone: (509) 853-3519 -- Email