Scientists determine how to control parasite without harming bees

Scientists determine how to control parasite without harming bees. Scientists at the University of Sussex have determined the best way of controlling Varroa mites - one of the biggest threats facing honey bees - without harming the bees themselves. A team from the Laboratory of Apiculture and Social Insects (LASI) has determined the best dose and method for treating hives with oxalic acid, a naturally occurring chemical already being used by beekeepers to control Varroa. The study, published today (Thursday 17 December 2015) in the Journal of Apicultural Research , shows that two of the three methods used by beekeepers to apply the chemical cause harm to bee colonies, resulting in reduced winter survival. But one method - sublimation, by which the chemical is vapourised inside the hive using an electrically heated tool - has no negative effect on the bees. In fact, colonies treated in this way had 20% more bees four months later than untreated colonies. It is also the easiest to use, the deadliest to the mites - killing 97% with one application - and is effective at lower doses than the other methods.