We measured faecal cortisol metabolites of a free-ranging riparian population of red deer to investigate potential effects of season, ambient temperature, precipitations and water level on the annual secretion pattern. Individuals may cope with environmental challenges through the secretion of stress hormones (glucocorticoids) which allows the integration of environmental change and life history traits by means of an adaptive feedback mechanism. Adaptations regard cyclic day-to-day activities, short-term environmental stressors or long-term ecological pressures. We detected a clear seasonal pattern of glucocorticoid metabolites secretion, with higher levels in winter and lower levels in summer. The model relating glucocorticoids secretion to minimum ambient temperature was the best fit to our dataset, although the observed pattern might as well be due to declining nutritional intake and reduction of metabolic rate in the cold season. We observed an improvement of the fit when stochastic events (flash flood) were included in the model, and discussed their role as potential contingent environmental stressors.
The only autochthonous population of Tatra chamois (Rupicapra rupicapra tatrica) occurs in the Tatra Mountains (northern Slovakia and southern Poland). Another population has been introduced to the Low Tatra Mts., while Alpine chamois (R. r. rupicapra) has been introduced to the neighbouring mountain ranges, Veľká Fatra and Slovenský raj. All these populations have undergone intensive bottlenecks. Any resulting low genetic variability would mean that only few genetic markers could be used for population genetic studies due to prevailing monomorphism. We tested 65 markers previously used in chamois or other Caprinae species, from which 20 most suitable loci for noninvasive genetic study of the Tatra chamois were selected. These polymorphic loci were used for optimisation of three multiplex sets and revealed a mean number of alleles of 2.1 and mean expected heterozygosity of 0.331 for the Tatra population. Low genetic diversity was also observed in the Low Tatra population while slightly higher values were obtained for Alpine chamois population in Slovenský raj. We subsequently assessed the amplification success rate for noninvasively obtained samples (faeces), which ranged from 85.1% to 92.7% for particular loci. The developed polymorphic microsatellite sets provide a unique tool for population genetic study of the endangered Tatra chamois, even when using noninvasive sampling, and is also suitable for Alpine chamois.
Food habits of blue sheep, Pseudois nayaur in the Helan Mountains of China were studied from November 2003 to October 2004 to better understand diet composition, seasonal variation, and feeding habitat preference. Blue sheep consumed 41 plant species that contributed >0.01% to the diets. During autumn, winter, and spring, primary species consumed were Stipa spp., Ulmus pumila, and Poa spp. Blue sheep also showed the different preference for these plant species. Graminoids were the largest proportion of the diet (36.7–58.8%) throughout the year, followed by the tree and shrub categories. Sedges were the smallest proportion of the diet (0.7–7.1%). Among the four habitat types, blue sheep showed pronounced preference for montane woodland steppe. Differences in the diets of Helan Mountains blue sheep from those of blue sheep elsewhere may reflect adaptations for geographical range, vegetation, and other factors.
For the last few decades, many studies have analysed the important influence of environmental conditions on the breeding biology of ungulates. However, with reference to Mediterranean wild boar populations, there are hardly any studies. In this paper, we will research the effect of rainfall over eight years on some reproductive variables in a wild boar population located in a Mediterranean ecosystem. Our results indicated that the percentage of pregnant females was higher in rainy years than in dry ones and females over 2 years of age significantly increased their litter size in these rainy years. In addition, dry summers and autumns determined an early rut period and a high concentration of births. However, rainfall did not influence the foetal sex ratio, although we did observe that the sex of the heaviest piglet within each litter was predominantly male, this circumstance being more significant in dry years than in rainy ones. We believe that these results could be showing the wild boar’s survival strategy in the changeable environmental conditions of Mediterranean ecosystems.
An experiment was conducted to monitor the effect of the length of environmental exposure of faeces on the content of nitrogen and diaminopimelic acid. We used samples of the droppings of wild red deer and examined them for the content of N and DAPA upon exposure to field conditions for 0–7 days during the growing season and for 0–30 days in winter, and after a year of storage in dried and frozen state. In relation to nitrogen level, there were no differences between the samples of fresh droppings and those after different lengths of exposure to ambient conditions before analysis and no differences between fresh and stored samples. As to DAPA level, there were no differences between the samples of fresh droppings and those after exposure. Nitrogen and DAPA levels in the droppings were stable and can be measured in both fresh samples and samples that have been exposed to ambient conditions for one week in summer or one month in winter.