Apidologie 33 (2002) 215-232
DOI: 10.1051/apido:2002003

Usurpation of African Apis mellifera scutellata colonies by parasitic Apis mellifera capensis workers

Stephen Martin^a, Theresa Wossler^b and Per Kryger<sup>b

a</sup>  Laboratory of Apiculture and Social Insect, Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
^b  Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa

(Received 1 November 2001; revised 12 December 2001; accepted 19 December 2001)

Abstract
Thelytokous Apis mellifera capensis workers recently brought into regions occupied by the arrkenotokous African bee A. m. scutellata, parasitise these colonies, causing colony death. These capensis workers are genetically almost identical and are referred to as a `pseudo-clone'. We surveyed 120 scutellata colonies, 27 in detail, at various stages of usurpation by the pseudo-clone. The scutellata queen could co-exist with egg-laying pseudo-clones for 50+ days in one case but disappeared 1-15 days in three other cases. Despite the presence of emerged queen cells no new adult queens of either race were observed in usurped colonies. Only 11 13% of the pseudo-clone population had fully active ovaries, suggesting ovarian development is inhibited in the majority of the pseudo-clones. Only 2.7 1.7% of the foraging force were pseudo-clones. The data were modelled and showed the rapid (56-105 days) growth of the pseudo-clone population and colony death over a wide range of initial conditions.

Key words: Apis mellifera capensis / pseudo-clone / usurpation / reproduction / Apis mellifera scutellata / honeybee reproduction / South Africa

Correspondence and reprints: Stephen Martin
    e-mail: s.j.martin@sheffield.ac.uk

© INRA, EDP Sciences, DIB, AGIB 2002