Urban environments alter parasite fauna, weight and reproductive activity in the quenda (Isoodon obesulus)

Some wildlife species are capable of surviving in urbanised environments. However, the implications of urbanisation on wildlife health, and public health regarding zoonoses, are often unknown. Quenda (syn. southern brown bandicoots, Isoodon obesulus) survive in many areas of Perth, Australia, despite urbanisation. This study investigated differences in gastrointestinal and macroscopic ecto-parasitic infections, morphometrics and reproductive status between bushland and urban dwelling quenda. 287 quenda in the greater Perth region were captured and sampled for faeces (to detect gastrointestinal parasites), blood (to detect Toxoplasma gondii antibodies), ectoparasites, and morphometrics. Data were analysed using multivariable logistic and linear regression. Most parasitic infections identified in quenda were of native parasite taxa that are either not known to, or considered highly unlikely to, infect humans or domestic animals. However, stickfast fleas (Echidnophaga spp.) were present at low prevalences and intensities, and Giardia spp., Cryptosporidium spp. and Amblyomma spp. infections require further investigation to clarify their anthropozoonotic significance. Quenda captured in urbanised environments had differing odds of or intensity of certain parasitic infections, compared to those in bushland - likely attributable to quenda population density, and in some cases the availability of other host species or anthropogenic sources of infection. Urbanised environments were associated with an increase in net weight of adult male quenda by 189.0g (95% CI 68.6-309.5g; p=0.002; adjusted R²=0.06) and adult female quenda by 140.1g (95% CI 3.9-276.3g; p=0.044; adjusted R²=0.07), with study findings suggesting a tendency towards obesity in urbanised environments. Adult female quenda in bushland had increased odds of an active pouch (adjusted OR=4.89, 95% CI 1.7-14.5), suggesting decreased reproductive activity in quenda from urbanised environments. These results highlight the subtle, yet extensive impacts that urbanised environments may have on wildlife ecology, even for those species which apparently adjust well to urbanisation.