Response of the small hive beetle (Aethina tumida) to honey bee (Apis mellifera) and beehive-produced volatiles

Abstract

-The response of male and female Small Hive Beetle (SHB), Aethina tumida, to air-borne volatiles from adult worker bees, (Apis mellifera), pollen, unripe honey, beeswax, wax by-products ("slumgum"), and bee brood, was investigated in olfactometric and flight-tunnel choice bioassays. In both bioassay systems, males and females responded strongly to the volatiles from worker bees, freshly collected pollen and slumgum but not to those from commercially available pollen, beeswax and bee brood. The response to pollen volatiles was dose dependent, while response to volatiles from worker bees increased with both the number and age of the bees. Females were more responsive than males to the different volatile sources, with greater response in tests with unripe honey. In flight-tunnel choice tests, Super Q-trapped volatiles from worker bees elicited a response comparable to the response to living workers, while trapped volatiles from other sources were not attractive.small hive beetle / Aethina tumida / hive volatiles / olfactometer / flight-tunnel

Small hive beetle,Aethina tumida, populations I: Infestation levels of honeybee colonies, apiaries and regions

“…However, SHB infestation levels did not correlate with any of the evaluated colony parameters; this is consistent with a previous study by Ellis and Delaplane (2006) on nucleus colonies. Colony volatiles might serve as cues for host finding (Elzen et al, 1999;Suazo et al, 2003;Torto et al, 2005), but appear to play a minor role only in host attractiveness. The strong bouquet of a whole colony might not enable any quantitative discrimination by SHB.…”

“…Since SHB are attracted to volatiles of honeybees and their stores (Elzen et al, 1999;Suazo et al, 2003;Torto et al, 2005), the infestation level of a colony might be influenced by its phenotype. Stronger colonies might harbour more SHB than weaker ones, because larger honeybee groups are more attractive to SHB than smaller ones (Suazo et al, 2003). Ellis and Delaplane (2006) investigated the potential influence of colony phenotypes on SHB infestation levels.…”

Novel antennal lobe substructures revealed in the small hive beetle Aethina tumida

“…However, a sequential arrival of male and female A. tumida could not be observed (Spiewok and Neumann, 2012). This does not rule out sex-specific differences in olfaction; females seem to be more responsive to beehive volatiles than males (Suazo et al, 2003), and this might be reflected in a sexual dimorphism of the olfactory system of A. tumida.…”

“…In summary, the absence of a sexual dimorphism in the olfactory pathway of A. tumida does not favor the work of Spiewok and Neumann (2012) or of Elzen (2004) and can on this level of analysis not add to an better understanding, why female A. tumida respond more strongly to beehive volatiles than males (Suazo et al, 2003). A detailed analysis of the A. tumida antenna including distribution of olfactory sensillae and identification and distribution of olfactory receptors would be necessary.…”

“…Spiewok and Neumann (2012) could not find any evidence that males enter the beehive before females. Paradoxically, females seem to be even more responsive than males to the different beehive volatile sources (volatiles from adult worker bees, pollen, unripe honey, beeswax, wax by-products, and bee brood) (Suazo et al, 2003). However, any possible use of a pheromone or different responses to beehive volatiles of males compared to females might be reflected in a sexual dimorphism of the olfactory system of A. tumida.…”