Bald-faced hornet hydrocarbons serve as a barrier to moisture diffusion and thus prevent dehydration in wasps. Cuticular hydrocarbon profiles vary over species and nests, and so cuticular hydrocarbons are a proposed mechanism for nest-mate recognition. Worker and queen cuticular lipids have similar components, but their distributions differ dramatically, implying that cuticular hydrocarbons also play a role in caste differentiation. The following lipid profiles were determined from specimens collected in the summer and early fall of northeastern Georgia in 1989. The dominant hydrocarbons recovered from the cuticles of workers were n-alkanes and methyl branched and dimethyl branched alkanes with a C27 or a
Bald-faced hornet colonies have been observed in central Pennsylvania as late as mid-October. The colony is founded by a single overwintered, inseminated queen. She rears the first generation of workers on her own until they are functional. Colonies pass through the foundation over an average period of 23–24 days. After the queen lays her eggs, it takes 6 days for them to hatch. They grow as larvae for eight days. It takes them an additional 9–10 days to mature into adult workers. During the ergonomic stage, the colony's activities are concerned with cell building and worker production. The queen devotes herself entirely