Behavioural basis for social parasitism of Cape honeybees (Apis mellifera capensis)

Abstract

-Cape honeybee workers show important pre-adaptations for social parasitism and can cause the dwindling colony syndrome of host colonies. Parasitic workers may drift or actively disperse into host colonies. They may also join absconding swarms, which can merge with host colonies. After transmission, parasitic workers have to establish themselves in the host, which is probably promoted by their spatial distribution, their readiness to gain trophallactic dominance and their ability to survive worker-worker aggression. Established parasitic workers have to evade egg removal by other workers in host colonies. The resulting offspring is preferentially fed, can be expected to be highly virulent and may show different behaviour in the course of infestation. It is unknown why and how the host queen is lost. High numbers of parasitic workers are reared until the host colony dies or absconds. This offspring can infest new host colonies, thereby completing the social parasitic life cycle.Apis mellifera capensis / Apis mellifera scutellata / honeybee / social parasitism / worker reproduction

Mandibular gland pheromone contents in workers and queens of Apis mellifera adansonii

“…9-HDA together with 9-ODA plays an active role in eliciting retinue responses (Slessor et al, 1988), maintaining swarm clusters (Winston et al, 1982), inhibiting queen rearing (Butler and Callow, 1968) and attracting drones (Brockmann et al, 2006). Workers producing queen-like signals in the presence of a queen could pose a threat to social organisation in colonies of other subspecies as seen in A. mellifera capensis workers when they invade colonies of other subspecies, but function effectively in their own colonies (reviewed in the study of Neumann and Hepburn 2002). At this point, we do not know if workers of A. mellifera adansonii will exhibit similar behavioural traits.…”

Honeybee health in Africa—a review

“…A. m. capensis workers are able to lay diploid eggs and produce queen-like signals (Onions 1912;Martin et al 2002;Neumann and Moritz 2002;Pirk et al 2012). These A. mellifera capensis social parasites do not contribute to the work force and their offspring do not replace the host workers, but these social parasites and their clonal offspring just reproduce which then results in the collapse of the host colony (Hillesheim et al 1989;Neumann et al 2001;Moritz 2002;Neumann and Hepburn 2002). This parasite is spread by migratory beekeepers during pollination and has resulted in large-scale colony losses with significant economic implications for the South African beekeeping industry (Allsopp and Crewe 1993;Johannsmeier 1994;Moritz 2002;Kryger et al 2003;Dietemann et al 2006;Pirk et al 2014).…”

The behaviour of drifted Cape honeybee workers (Apis mellifera capensis): predisposition for social parasitism?

“…Laying workers of the Cape honeybee, Apis mellifera capensis Escholtz, are facultative social parasites (Neumann and Hepburn, 2002;Neumann and Moritz, 2002) and individual workers can enter new host colonies by drifting (Neumann et al, 2001b). Drifting results from orientation errors of young workers during their orientation flights and of returning foragers (Rauschmayer, 1928;Free, 1958;Pfeiffer and Crailsheim 1998;Neumann et al, 2000).…”

“…In particular, the development of queen-like pheromones appears to be an essential part of the social parasitic pathway of A. m. capensis workers (Wossler, 2002;Neumann and Hepburn 2002). However, the pheromonal bouquet of the host queen might suppress the ovarial development of the drifted workers unless they already show some pre-drifting ovarial development (Reece, 2002;Neumann and Hepburn, 2002). One mechanism to avoid the suppressive signals of the host queen may be simply to evade the queen's mandibular gland signals and remain in areas of low 9-ODA concentration in the colony (Neumann and Moritz, 2002).…”