EFFECT OF MATING FREQUENCY AND BROOD CELL INFESTATION RATE ON THE REPRODUCTIVE SUCCESS OF THE HONEYBEE PARASITE VARROA-JACOBSONI

1. The reproductve biology of Varroa jacobsoni, whose females infest h oneybee brood, was studied in natural and transparent artificial brood cells. These investigations were made under the headings of maturatio n behaviour and fertilization, and the influence of infestation rate o f brood cells on the number of mated females produced per infesting Va rroa. 2. Mating of Varroa daughters, observed in the transparent brood cells with time-lapse video, occurs just after ecdysis and as soon as they arrive on the faecal accumulation prepared by the mother. Such f emales are remated for as long as no other freshly moulted daughter ar rives on the faecal accumulation. 3. The number of spermatozoa stocked in the spermatheca increases with remating, a strong indication for s perm mixing in this species when brood cells contain more than one Var roa foundress. 4. The number of daughters per infesting mother decreas es at higher rates of infestation per cell, but the proportion of such daughters with a mate rises sharply due to the higher probability of finding a male within multi-infested cells. The number of mated daught ers per mother is maximal in cells with two foundress Varroa females. 5. The frequency distributions of infesting mites in drone cells are a ggregated, and approximate to negative binomial distributions. 6. We P ostulate from the above that the observed non-random infestation by Va rroa in drone brood augments the mite's mean reproductive success thro ugh the production of a higher number of mated daughters than the corr esponding Poisson distributions would.