Slabezki, Y., Beekeeping Division, Extension Service, Ministry of Agriculture, POB 7054, Tel Aviv, Israel
Efrat, H., Zerifin Breeding Apiary, ARS, Volcani Center, POB 6, Bet Dagan 50250, Israel
Dag, A., Beekeeping Division, Extension Service, Ministry of Agriculture, POB 7054, Tel Aviv, Israel
Kamer, Y., Zerifin Breeding Apiary, ARS, Volcani Center, POB 6, Bet Dagan 50250, Israel
Yakobson, B.A., Kimron Veterinary Institute, Bet Dagan 50250, Israel
Mozes-Koch, R., Department of Entomology, Fac. of Agric., Food and Environ. Q., Hebrew University, Rehovot 76100, Israel
Gerson, U., Department of Entomology, Fac. of Agric., Food and Environ. Q., Hebrew University, Rehovot 76100, Israel

Infestations by honey bee tracheal mite, Acarapis woodi (Rennie) (HBTM), were followed in three groups for one year. The groups consisted of 1) acaricide (amitraz) treated Italian bee colonies, 2) untreated Italian bee colonies, and 3) untreated Buckfast colonies. Mite prevalence of Buckfast bees declined from 45% in December to 10% in April and remained low, and most queens persisted for the entire period. Furthermore, bee populations increased and honey yield was high in comparison to seasonal averages. HBTM prevalence in the treated Italian colonies remained low until July, with a large increase in bee populations and honey yield, similar to that of the Buckfast colonies; however only a quarter of the queens survived. The untreated colonies were severely infested by the mite and much reduced in population, produced little honey and most of their queens were replaced. Nosema infections and Varroa mite prevalence rates were similar in all treatments. Along with a documentation of HBTM damage and control, this is also the first demonstration of the resistance of Buckfast bees to A. woodi under Mediterranean conditions.