Endoparasites in the endangered Fennoscandian population of arctic foxes (Vulpes lagopus)

The Fennoscandian arctic fox (Vulpes lagopus) population is endangered due to overharvest and competition with the larger red fox (Vulpes vulpes). In this study, we have screened the population in Sweden for endoparasites by analysis of non-invasively faecal samples collected at reproductive dens during two summers, one with low food abundance (2008) and the other with high food abundance (2010). Eggs, larvae and oocysts of a total of 14 different endoparasites were identified with a species richness per inhabited den of 3.2 (CI95% ± 0.48) in 2008 and 2.7 (CI95% ± 0.72) in 2010. Capillariidae-like eggs was identified at 59% of the dens in 2008 and 57% in 2010 and Toxocara canis with 7% (2008) and 30% (2010); Toxascaris leonina with 93% (2008) and 65% (2010); Uncinaria stenocephala 65% (2008) and 39% (2010); Crenosoma vulpis 3% (2008) and 4% (2010); Trichuris sp. 7% (2008) and 4% (2010); Cystoisospora canis-like oocysts 28% (2008) and 26% (2010); Cystoisospora ohiensis-like oocysts 38% (2008) and 4% (2010); Eimeria sp. 7% (2008) and 9% (2010); Sarcocystis sp. 3% (2008) and 9% (2010); Taenia sp. 10% (2008) and 4% (2010); Mesocestoides sp. 3% (2008) and 0% (2010); Balantidium sp. 0% (2008) and 9% (2010) and Spiruroidea-like eggs 0% (2008) and 4% (2010). To our knowledge, Balantidium sp., Sarcocystis sp. and Trichuris sp. has never been described before in wild arctic foxes.