Abstract:
Migratory behavior of the giant honeybee; Apis dorsata F. was observed in northern Thailand from 1995-1998. Relatedness of colonies was determined using three microsatellite loci (A14, A88 and B124). The microsatellite results demonstrate that the colonies seasonally occupied the same nest site were not related. The results suggest that A. dorsata swarms probably do not return to their parental nest sites after migration. The genetic results of aggregated colonies on a single support demonstrate that aggregated colonies were combination of related and unrelated colonies. However, related colonies were nested far away (>2.5 m) whereas and unrelated colonies nested closer. The results suggest that related swarms preferentially migrated a short distance whereas the unrelated swarms preferentially nested closer in order to provide mutual defense and to enhance outbreeding. The migratory observations indicate that A. dorsata seasonally altered their nest site. In winter (January) when the ambient temperature dropped below 16 ํC, A. dorsata started to migrate due to unable to maintain their optimum brood nest temperature (>35 ํC). Wind speed (>29 km/h) also induced colony migration by dislodging their nests. Similarly predators caused all colony migration whereas parasite pressure seems negligible.
