The rarer sex - female natal dispersal and breeder replacement in the southern anteater-chat Myrmecocichla formicivora.
(English)Manuscript (preprint) (Other academic)
Sex biased dispersal is a crucial factor in understanding the mechanism of family dynamics in many cooperative breeders. Female biased dispersal occurs in many cooperatively breeding birds. It is often associated with females dispersing earlier and further, and a male biased sex skew in the population. Here we investigated female dispersal in the southern anteater-chat, a facultative cooperatively breeding passerine of southern Africa. Our study population had a male biased sex skew, and females had lower annual survival than males. Dispersal was strongly female biased, with females dispersing within their first year whereas many males remained philopatric beyond the next breeding season. Breeding females were on average younger than breeding males, and also dispersed further. Each breeding group contained only one female. No females were found floating in the population, and all females were associated with one or more males in a breeding group. It appears that all females disperse in their first year directly to a breeding position. If a female disappeared in the breeding season they were not replaced until new females matured and dispersed the following season, yet if a male breeder disappeared during the breeding season he was almost immediately replaced, indicating that there are no surplus females.
Southern anteater-chat, cooperative breeding, social evolution, behavioural ecology, delayed dispersal, family living, Africa
Research subject Biology with specialization in Population Biology
IdentifiersURN: urn:nbn:se:uu:diva-179073OAI: oai:DiVA.org:uu-179073DiVA: diva2:544040