Ectoparasites associated with the Bushveld gerbil (Gerbilliscus leucogaster) and the role of the host and habitat in shaping ectoparasite diversity and infestations

Abstract

Rodents are known hosts for various ectoparasite taxa such as fleas, lice, ticks and mites. South Africa is recognized for its animal diversity, yet little is published about the parasite diversity associated with wild rodent species. By focusing on a wildlife-human/domestic animal interface, the study aims to record ectoparasite diversity and levels of infestations of the Bushveld gerbil, Gerbilliscus leucogaster, and to establish the relationship between ectoparasite infestation parameters and host- and habitat factors. Rodents (n = 127) were trapped in 2 habitat types (natural and agricultural) during 2014–2020. More than 6500 individuals of 32 epifaunistic species represented by 21 genera and belonging to 5 taxonomic groups (fleas, sucking lice, ticks, mesostigmatan mites and trombiculid mites) were collected. Mesostigmatan mites and lice were the most abundant and fleas and mesostigmatan mites the most prevalent groups. Flea and mesostigmatan mite numbers and mesostigmatan mite species richness was significantly higher on reproductively active male than female rodents. Only ticks were significantly associated with habitat type, with significantly higher tick numbers and more tick species on rodents in the natural compared to the agricultural habitat. We conclude that the level of infestation by ectoparasites closely associated with the host (fleas and mites) was affected by host-associated factors, while infestation by ectoparasite that spend most of their life in the external environment (ticks) was affected by habitat type.

Effects of Season, Habitat, and Host Characteristics on Ectoparasites of Wild Rodents in a Mosaic Rural Landscape

“…Therefore, our results may be, after all, in line with the dilution effect theory. In addition, ticks and mites, during their off-host period, are sensitive to environmental factors, and the canopy of woody plants creates a relatively stable microclimate of favourable conditions, enhancing their survival [62]. For ticks, vegetation structure and the presence of shrubs are also important in questing and finding a host [63].…”