Poster Presentation 64th International Conference of the Wildlife Disease Association 2015

To treat or not to treat? Investigating the impact of polyparasitism in translocated woylies (Bettongia penicillata), and the effect of anti-parasite treatment on host fitness and survivability (#115)

Amy S. Northover 1 , Stephanie S. Godfrey 1 , Alan J. Lymbery 1 , Adrian F. Wayne 2 , Keith Morris 2 , R.C. Andrew Thompson 1
  1. Murdoch University, Murdoch, WA, Australia
  2. Science Division, Department of Parks and Wildlife, Manjimup, WA, Australia

Polyparasitism, in which a host is co-infected with various parasite species or intraspecific strains, is common in wild animal populations. Whilst parasites have been implicated in a number of species declines, the role of polyparasitism as a potential factor contributing towards translocation failures has never been investigated. This project is currently evaluating how fauna translocations impact the transmission of parasites in woylies (Bettongia penicillata), and what consequences this has for translocated hosts and other cohabiting species. We are testing the hypothesis that fauna translocations lead to a higher diversity of parasites within the resultant host-parasite community, and thus a higher incidence of polyparasitism; which in conjunction with the disruption of established host-parasite associations, may exacerbate the negative impacts of parasites on their hosts to the detriment of translocation success. Secondly, as the effects of anti-parasite treatment in translocated hosts are relatively unknown; we are also assessing the effect of parasite removal in translocated hosts. We are testing the hypothesis that anti-parasite treatment reduces the incidence of polyparasitism, thereby improving host fitness and survivability. In June 2014, 182 woylies were translocated from Perup Sanctuary to two unfenced sites within Western Australia. Pre- and post-translocation, woylies from both the source and destination sites were measured and weighed, and pouch activity was recorded for females. Blood, ectoparasite and faecal samples were also collected for parasitological examination. In each destination site, cohabiting species were sampled to quantify parasite transmission between species post-translocation. In order to evaluate the effect of anti-parasite treatment, we treated half the woylies with Ivermectin prior to translocation and repeated our sampling at four and 12 weeks post-treatment. We have observed changes to the predominant species of Trypanosoma in woylies pre- and post-translocation, and that anti-parasite treatment has had an effect on both target and non-target parasites of the translocated hosts.