Genetic diversity and parasite prevalence in two species of bumblebee

• Published in: Journal of insect conservation 2014-08, Vol.18 (4), p.667-673
• Main Authors: Whitehorn, Penelope R, Tinsley, Matthew C, Brown, Mark J. F, Darvill, Ben, Goulson, Dave
• Format: Article
• Language: English
• Subjects: Animal diseases; Animal Ecology; Animal, plant and microbial ecology; Applied ecology; Bees; Biodiversity; Biological and medical sciences; Biomedical and Life Sciences; Bombus; Bombus muscorum; Conservation biology; Conservation Biology/Ecology; Conservation, protection and management of environment and wildlife; Ectoparasites; Entomology; Fundamental and applied biological sciences. Psychology; Genetic diversity; genetic variation; Habitat fragmentation; heterozygosity; Inbreeding; inbreeding depression; Life Sciences; Mites; Original Paper; Parasites; Parks, reserves, wildlife conservation. Endangered species: population survey and restocking; Rare species
• ISSN: 1366-638X; 1572-9753
• DOI: 10.1007/s10841-014-9673-1

Many bumblebee species have been suffering from significant declines across their ranges in the Northern Hemisphere over the last few decades. The remaining populations of the rare species are now often isolated due to habitat fragmentation and have reduced levels of genetic diversity. The persistence of these populations may be threatened by inbreeding depression, which may result in a higher susceptibility to parasites. Here we investigate the relationship between genetic diversity and prevalence of the parasitic mite Locustacarus buchneri in bumblebees, using the previously-studied system of Bombus muscorum and Bombus jonellus in the Western Isles of Scotland. We recorded L. buchneri prevalence in 17 populations of B. muscorum and 13 populations of B. jonellus and related the results to levels of heterozygosity. For B. muscorum, we found that prevalence of the mite was higher in populations with lower genetic diversity but there was no such relationship in the more genetically diverse B. jonellus. In contrast to population-level measures of genetic diversity, the heterozygosity of individual bees was not correlated with infection status. We suggest population-level genetic homogeneity may facilitate parasite transmission and elevate prevalence, with potential consequences for population persistence.