Grooming behavior by Apis mellifera L. in the presence of Acarapis woodi (Rennie) (Acari: Tarsonemidae)

Abstract

The role of grooming behavior by the honey bee, Apis mellifera L., in limiting the infestation of, or being elicited by, the parasitic mite Acarapis woodi was investigated. Grooming behaviors examined included allogrooming and the grooming dance that involves self or autogrooming. Observation hives monitored over 24 h revealed that dancing increased significantly at night while allogrooming decreased. In 32 mite-infested observation hives the percentage of bees infested was positively correlated with allogrooming acts and dances observed. In a third experiment, young marked bees were introduced into three hives with 0, 50 and 70 % tracheal mite prevalence and grooming dances increased significantly in the bees 1-3 d of age in the mite-infested colonies. We postulate that mite movement on young bees elicits the grooming dance. Bees from four different single patrilines that had exhibited different propensities to allogroom or dance were marked and placed into eight mite-infested colonies for 5 d. Dissections of marked bees revealed that the allogrooming line was most susceptible and the dancing line least susceptible to mite infestation. We postulate that the dancing line of bees had a lower threshold for detecting mites on their body resulting in increased dance behavior and autogrooming, which we propose lowered the number of mites that transferred to these bees. This is the first evidence for a mechanism of resistance to the honey bee tracheal mite.