This study was designed to investigate the pharmacokinetics of imidocarb, a carbanilide derivative, in white‐tailed deer (Odocoileus virginianus). The pharmacokinetic properties of a single intramuscular (IM) dose of imidocarb were determined in 10 deer. A single IM injection of 3.0 mg/kg imidocarb dipropionate was administered, and blood samples were collected prior to, and up to 48 hr after imidocarb administration. Plasma imidocarb concentrations were determined by high‐performance liquid chromatography with ultraviolet detection. The disposition of plasma imidocarb was best characterized by a two‐compartment open model. The mean ± SE maximal imidocarb concentration in deer was 880.78 ± 81.12 ng/ml at 38.63 ± 5.30 min postinjection. The distribution phase had a half‐life (t1/2α) of 25.90 ± 10.21 min, and plasma imidocarb concentration declined with a terminal elimination half‐life (t1/2β) of 464.06 ± 104.08 min (7.73 ± 1.73 hr). Apparent volume of distribution based on the terminal phase (VZ/F) was 9.20 ± 2.70 L/kg, and apparent total body clearance (Cl/F) was 15.97 ± 1.28 ml min−1 kg−1.

Psoroptes are a non-burrowing, ectoparasitic, mange-causing mite that has been documented in American bighorn sheep populations throughout the 19th and 20th centuries; however, it was not seen on Canadian bighorn sheep until 2006. The aim of this study was to determine the potential source of the Psoroptes outbreak in Canadian bighorn sheep. Morphological and molecular analyses were used to compare mites recovered from outbreak-associated bighorn sheep, pet rabbits in Canada, and on historically infested bighorn sheep in the USA. The results revealed that Psoroptes acquired from the Canadian and outbreak-associated American bighorn sheep were morphologically more similar to those collected from rabbits than mites on historically infested bighorn sheep. Outer opisthosomal setae lengths measured an average of 81.7 μm (±7.7 μm) in outbreak associated bighorn mites, 88.9 μm (±12.0 μm) in rabbit mites and 151.2 μm (±16.6 μm) in historically infested bighorn mites. The opisthosomal lobe morphology of bighorn mites in the outbreak herds was also more similar to that of rabbit mites, previously described as P. cuniculi , than historically infested bighorn mites, which match previous descriptions of P. ovis . This finding was supported by DNA sequence data of the mitochondrial cytochrome B gene. This is the first report of Psoroptes of the rabbit ecotype on bighorn sheep. The morphological and molecular data therefore support the hypothesis that the source of Psoroptes outbreak in Canadian bighorn sheep represented a disease spillover event from rabbits rather than transmission from infested American bighorn sheep populations.

The global urban population is expected to increase by 2.5 billion people over the next 30 years. Yet the doubling of urban landscapes in the last decades have already led to habitat loss and concomitant impacts to biodiversity. Nonetheless urban landscapes remain important for wildlife, and global syntheses have revealed that wealthy urban areas house more biodiversity, a ‘luxury effect’. We researched some of the mechanisms for the luxury effect for urban black-tailed deer, a species of increasing concern in urban landscapes across the northwestern Nearctic. We satellite collared twenty deer in an urban landscape in British Columbia, Canada, with high-resolution fix rates. We used generalized models in an information-theoretic framework to weigh evidence for competing hypotheses about the role of tree cover, productivity, public green spaces, and wealth in explaining deer selection. Wealth, manifesting as housing lot size, emerged as the dominant predictor of deer space-use, which is highly concentrated into very small home-ranges. Other landscape elements stemming from affluence, including golf courses and parklands, were also strongly selected by deer. We show post-colonization landscape conversion from dry semi-arid savannah to well-watered high-productivity landscapes is supporting deer, with ramifications for the rest of the biotic community. With urban landscapes becoming an increasingly important for biodiversity conservation, understanding these mechanisms can help to promote wildlife-human coexistence.