The small hive beetle invades colonies of the European honeybee (Apis mellifera) but not of the African strain. Researchers in the US have now found that the bee's very own chemical alarm signal plays an important role in the beetle's success.

Peter Teal and colleagues at the University of Florida used analytical techniques, including GC-MS, to study the chemical messengers (pheromones) that bees send out when they are under stress. The researchers were surprised to find that the parasitic beetle can detect at least one of the bee's alarm pheromones, isopentyl acetate (IPA), with a much better sensitivity than the bee itself. Thus, the beetles can rely on the bee's chemical signals to localise bee hives, and to congregate in large numbers on bee hives that are already in trouble.

Michael Gross