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Although weather-induced mass mortalities of wild ungulates have been reported, no study has quantified how these episodes may affect the survival of prime-aged adults. Long-term studies of marked ungulates have instead consistently found very weak or no effects of weather on the survival of this age class, particularly for females. We report on the effects of the exceptionally snowy winter of 2008–2009 on three populations of chamois in the western Alps: two in Italy, one in France. In the Alpi Marittime Natural Park in Italy, mortality of prime-aged females (aged 2–9 years) was 43%, about five times higher than reported by previous studies of chamois. Just across the continental divide in the adjacent Mercantour National Park (PNM) in France, however, prime-aged female mortality was only 6%. Senescent females suffered very high mortality in both populations (100% and 56%). In the Gran Paradiso National Park in Italy and in the Alpi Marittime Natural Park, adult male mortality rate was respectively of 81% and 44%, whereas in the PNM, it was only 10%. A recent reduction in population density in the French population, or lower absolute snowfall than in Italy, may explain the difference in survival. Survival of males and prime-aged females can be affected by exceptional weather events, possibly in combination with high population density. Adult chamois of both sexes appeared to show elevated mortality in response to harsh winter conditions. Our results underline the importance of considering sex and age classes in evaluating the impacts of population density in wild ungulates.
Examination of 599 faecal samples taken over the years 1984-1993 from Alpine chamois in the Slovak Paradise National Park revealed the presence of lung nematodes Muellerius capillaris, Muellerius tenuispiculatus, Neostrongylus linearis and Dictyocaulus viviparus. Their total prevalence in chamois herds was 57.7%. Muellerius spp. were predominant (56.5%), N. linearis occurred in about half less amount (29.2%) and D. viviparus was prevalent in 2.5%. The prevalence of lung nematodes in chamois herds fluctuated with years from 41.4 to 69.4% and with seasons of the year from 33.3 to 83.3%. Mean larval count per gram faeces in individual years ranged between 73.7 ± 60.1 and 148.5 ± 58.0. Chamois herds were significantly less infected in summer seasons (P<0.05) than in other seasons, except for the summer of 1986, 1988, 1989 and winter of 1989. A necropsy confirmed the presence of adult stages of all three nematodes in the lung parenchyma, but in bronchi and trachea no adults of D. viviparus were observed. Mean larval count per gram lung tissue was high (152 ± 20.9 to 270 ± 19). The wide diversity of snail species in the territory of the Slovak Paradise, their great ability to serve as intermediate hosts of lung nematodes in various biotopes create appropriate conditions for the development of lung nematodes and consequently for the infection of chamois in the Slovak Paradise reserve.
We examined 617 kills made by radio-tracked Eurasian lynx Lynx lynx (Linnaeus, 1758) from March 1988 to May 1998 to assess prey spectrum, preference, and food consumption rates in the Swiss Jura Mountains. Roe deer Capreolus capreolus and chamois Rupicapra rupicapra were the main prey (69 and 22%, respectively), followed by red fox Vulpes vulpes, brown hare Lepus europaeus, domestic cat Felis calus, wild cat Fclis sylvestris, marmot Marmota marmota, pine marten Martes marles, capercaillie Telrao urogallus, and badger Meles meles. Lynx fed on an ungulate prey from 1 to 7 days, depending on the prey category. The consumption rates of males, of females alone, and of females with kittens varied from 3.2 to 4.9 kg per night, with an increasing trend as the kittens grew older. Including the days when lynx had no kill (searching time) lynx consumed 2 ± 0.9 kg per night. The mean searching time was 1.5-2 days for females, depending on the season and the number of kittens, and 2.5 days for males. The mean interval between consecutive kills was 5.9 for males and 5.2 days for females, respectively. At 38% of carcasses the presence of one or several scavengers (red fox, raven Corvus corax or both) was detected, Although 69% of the kills were roe deer and only 22% chamois, we hypothesise that in the forests of the Jura Mountains chamois are more vulnerable to lynx predation than roe deer, as chamois had a slightly higher preference index (0.59) than roe deer (0.41), based on rough estimates of the two ungulate populations in the study area.
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