Mortality of Varroa jacobsoni Oudemans during or soon after the emergence of worker and drone honeybees Apis mellifera L

In a naturally infested colony a strong con-elation between levels of falling mites and the emergence of honeybee brood was found. When comparing the number of mires falling between emerging worker and drone brood with known infestation levels, the mite fall was 2-3 times higher from worker than from drone cells. It was estimated that around half of the falling mites originate from mites that died within the sealed cell with the other half dying shortly after bee emergence. About 50% of the fallen mites were still alive and found to be able to reproduce when artificially introduced into sealed brood cells. The implications of mite mortality associated with brood emergence on the mite population dynamics and of using numbers of falling mites as a monitoring tool are discussed.