Alternative food sources of Aethina tumida (Coleoptera: Nitidulidae)

The small hive beetle (SHB) is a parasite and scavenger of honey bee colonies, but may also be able to exploit alternative food sources. We conducted experiments to shed further light on the role of alternative foods for SHB. I) Laboratory choice experiments showed that adult SHB oviposit on fruit and even on decaying meat and that SHB larvae feed on it despite the presence of bee products. 2) In the laboratory, SHB reproduced on mango, banana and grapes at lower rates than on a pollen and honey mixture. 3) Adult SHB were rarely observed on fruit buckets in the field. They reproduced only when caged and in much smaller numbers than Drosophilidae and other Nitidulidae. 4) While Aethina concolor was repeatedly observed during a field survey, no adult SHB were found on any flowers. 5) Less than 2% of adult SHB survived on blooming pot plants and no reproduction was recorded, suggesting that flowers are unlikely to serve as an alternative food and breeding substrate. Nevertheless, the high degree of opportunism displayed, supports the view that honey bee nests are not essential for SHB survival and reproduction. Despite the observed high degree of SHB opportunism, it appears as if alternative food sources play a minor role only for reproduction in the field when host colonies are available. Even though SHB may use alternative food sources in the absence of bee hives (e.g. after migratory beekeeping), it is unclear whether this is likely to contribute to SHB population build up.