Timing of drone flights and observations of other colony behaviors of Apis laboriosa in northern Vietnam

Abstract

We studied an aggregation of Apis laboriosa colonies in northern Vietnam where the species is sympatric with Apis dorsata. We video-recorded four colonies on 2 days to quantify drone flights and other colony behaviors. We observed > 90% of drones between 16:10 and 18:10 h ICT, with the maximum numbers between ~ 17:10 and 18:00 h. Drone flight timing did not differ between days or between colonies. Aggressive worker behavior toward some arriving drones suggests considerable drifting of drones between nests. Massed flight activity, a colony behavior in which a high proportion of bees temporarily leaves the comb, occurred in several colonies between 14:00 and 16:40 h. We also documented absconding by one colony. A. laboriosa drones ended their mating flights before the typical mating flight time of Apis dorsata at evening twilight. We conclude that allochrony of mating is a likely reproductive isolating mechanism between these two species of giant honey bees.