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A recent increase in the area open to hunters in the Swedish mountains has directed attention to the possibility of overharvesting and greater wildlife disturbance. Using radio-telemetry, the movements of willow grouse Lagopus lagopus in a heavily hunted area were compared to movements in areas where hunting was prohibited. Although hunter density was higher than the regional average, no significant differences in movements, measured as rate or distance, between grouse in hunted and unhunted areas were found. Willow grouse did not move out of the hunted area, a common belief amongst many hunters. Seasonal migration was not induced by deliberate human disturbance. It is suggested that grouse reduce the risk of being killed by habitually moving within a familiar area with known escape sites (cover). Neither hunting, deliberate flushing or catch and release caused a change in the movement patterns of willow grouse. It is suggested that such disturbances were perceived as part of a naturally unpredictable predator environment, and not sufficient to alter grouse movements.

We tested the hypothesis that helminth parasitism is demographically significant to a noncyclic population of snowshoe hares (Lepus americanus) near the species' geographic boundary in central Wisconsin (U.S.A.). During November 1988 to December 1991, we injected 93 individuals (≥760 g, aged ≥2 months) with anthelmintics: Ivermectin for nematode and Droncit for cestode infections. We injected 98 control hares with propylene glycol, the common vehicle for both drugs. All treated and control hares were radio-collared with mortality-sensing transmitters and monitored daily to weekly from the ground or air. Prevalence and intensity of lungworms (Protostrongylus boughtoni), intestinal worms (Nematodirus triangularis), and stomach worms (Obeliscoides cuniculi) were markedly reduced by Ivermectin treatment. No other nematodes were found to be present. Treatment with Droncit to remove intestinal cestodes was apparently unnecessary, as prevalence among necropsied untreated hares and controls was just 10%. We compared body-condition indices (mass changes, response to trap stress, and bone-marrow fat), reproduction (pregnancy rate and litter size), home-range sizes, and time-specific survival rates of anthelmintic-treated versus control hares. None of these demographic variables differed significantly between treated and control cohorts, nor was there any evidence that parasitism increased the risk of death from predation, which was the proximate cause of 96% of all natural mortalities. We conclude that helminth parasitism played no detectable role in the dynamics of this Wisconsin snowshoe hare population.