Apiacta #2, Feb., 1984

Roger A. MORSE

The honey bee parasite, Varroa jacobsoni: must enter the cells of drones or worker bees in order to reproduce. The selection of an appropriate cell is of utmost importance to the mite and, ultimately affects both the rate of mite population increase and the damage to individual bees and to the colony as a whole.

Some factors examined which influence this selection are the age, sex, and caste of the larva, presence and proximity of queen cells, and architecture.

Independently of these influences, it appears that the mites are clumped in their distribution among cells, implying that they do tend to enter cells already occupied by other mites. This may be a mechanism to help decrease the incidence of inbreeding among the mite progeny.

Nevertheless, the mites are not greatly clumped in worker cells. Few bees in the infestations we see in Brazil are visibly injured, making evaluation of damage difficult. However, there is a consistent loss in weight and a drastic decrease in lifespan, even of bees infested with a few mites. But the bees can emerge from their cells, releasing the mites and their progeny to continue their infestive cycle.