2023/06/13 by Dominik M. Behr, Florian H. Hodel, Gabriele Cozzi +2 · 1 voice · 8 citations
Biochemistry, Genetics and Molecular Biology · Environmental Science · #Animal Ecology and Behavior Studies #Biological dispersal #Biology #Demography #Ecology #Endangered species #Habitat #Human-Animal Interaction Studies #Mortality rate #Population #Trait #Wildlife Ecology and Conservation
paper · doi:10.1086/726220
published in The American Naturalist 202(5), 616-629 (University of Chicago Press)
openalex publication_date 2023/06/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
Mortality is considered one of the main costs of dispersal. A reliable evaluation of mortality, however, is often hindered by a lack of information about the fate of individuals that disappear under unexplained circumstances (i.e., missing individuals). Here, we addressed this uncertainty by applying a Bayesian mortality analysis that inferred the fate of missing individuals according to information from individuals with known fate. Specifically, we tested the hypothesis that mortality during dispersal is higher than mortality among nondispersers using 32 years of mark-resighting data from a free-ranging population of the endangered African wild dog (Lycaon pictus) in northern Botswana. Contrary to expectations, we found that mortality during dispersal was lower than mortality among nondispersers, indicating that higher mortality is not a universal cost of dispersal. Our findings suggest that group living can incur costs for certain age classes, such as limited access to resources as group density increases, that exceed the mortality costs associated with dispersal. By challenging the accepted expectation of higher mortality during dispersal, we urge for further investigations of this key life history trait and propose a robust statistical approach to reduce bias in mortality estimates.