17 research outputs found
Seasonal and biogeographical patterns of gastrointestinal parasites in large carnivores: wolves in a coastal archipelago
Parasites are increasingly recognized for their profound influences on individual, population and ecosystem health. We provide the first report of gastrointestinal parasites in gray wolves from the central and north coasts of British Columbia, Canada. Across 60 000 km 2, wolf feces were collected from 34 packs in 2005-2008. At a smaller spatial scale (3300 km 2), 8 packs were sampled in spring and autumn. Parasite eggs, larvae, and cysts were identified using standard flotation techniques and morphology. A subset of samples was analysed by PCR and sequencing to identify tapeworm eggs (n=9) and Giardia cysts (n=14). We detected ≥14 parasite taxa in 1558 fecal samples. Sarcocystis sporocysts occurred most frequently in feces (43·7%), followed by taeniid eggs (23·9%), Diphyllobothrium eggs (9·1%), Giardia cysts (6·8%), Toxocara canis eggs (2·1%), and Cryptosporidium oocysts (1·7%). Other parasites occurred in 1% of feces. Genetic analyses revealed Echinococcus canadensis strains G8 and G10, Taenia ovis krabbei, Diphyllobothrium nehonkaiense, and Giardia duodenalis assemblages A and B. Parasite prevalence differed between seasons and island/mainland sites. Patterns in parasite prevalence reflect seasonal and spatial resource use by wolves and wolf-salmon associations. These data provide a unique, extensive and solid baseline for monitoring parasite community structure in relation to environmental change
Heavily hunted wolves have higher stress and reproductive steroids than wolves with lower hunting pressure
Population structure and dispersal of wolves in the Canadian Rocky Mountains
In the Canadian Rocky Mountains, the gray wolf (Canis lupus) has experienced range contractions and expansions, which can greatly affect pack stability as well as population structure. In addition, this area has a highly heterogeneous landscape that may form barriers to dispersal. To understand factors affecting pack structure and large-scale gene flow across the Rocky Mountains, we examined wolf genetic structure using 1,981 noninvasive and invasively collected samples. We sampled over 44 packs in Alberta and British Columbia and, from these, identified 540 individuals based on 12 microsatellites. Relatedness of individuals within packs was greater than between packs, and female relatedness was greater than males suggesting strong pack structure and female philopatry. Relatedness within packs was greater near major roads suggesting decreased dispersal from natal packs with proximity to roads. Across the study area, 2 significantly differentiated genetic clusters were identified, corresponding to a north/south split. Landcover distance was a significant correlate for 2 of 4 genetic distance measures, where packs in the north were in areas of dense coniferous forest, while packs in the south were primarily in open coniferous forest. These landcover differences suggest natal associations or could relate to prey distribution. Fine-scale investigation of pack dynamics across this continuous distribution, together with large-scale estimators of population structure, highlights different drivers of gene flow at the pack and population level