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We studied the response of the barn owl annual productivity to the common vole population numbers and variability to test the effects of environmental stochasticity on their life histories. Current theory predicts that temporal environmental variability can affect long-term nonlinear responses (e.g., production of young) both positively and negatively, depending on the shape of the relationship between the response and environmental variables. At the level of the Czech Republic, we examined the shape of the relationship between the annual sum of fledglings (annual productivity) and vole numbers in both non-detrended and detrended data. At the districts’ level, we explored whether the degree of synchrony (measured by the correlation coefficient) and the strength of the productivity response increase (measured by the regression coefficient) in areas with higher vole population variability measured by the s-index. We found that the owls’ annual productivity increased linearly with vole numbers in the Czech Republic. Furthermore, based on district data, we also found that synchrony between dynamics in owls’ reproductive output and vole numbers increased with vole population variability. However, the strength of the response was not affected by the vole population variability. Additionally, we have shown that detrending remarkably increases the Taylor’s exponent b relating variance to mean in vole time series, thereby reversing the relationship between the coefficient of variation and the mean. This shift was not responsible for the increased synchrony with vole population variability. Instead, we suggest that higher synchrony could result from high food specialization of owls on the common vole in areas with highly fluctuating vole populations. [ABSTRACT FROM AUTHOR]

We studied winter climate influences on central European small herbivores by testing the prediction that direct physical effects of winter climate should be more pronounced in herbivores living above ground/snow than in subnivean/fossorial ones. Using correlation analysis and autoregressive modeling, we found that population growth rates of European hares, representing the former class of herbivores, are more efficiently predicted by the winter NAO index than those of common voles, representing the latter class of herbivores. We demonstrate that, whereas in hares the NAO index outperformed crop yield indices, used here as a proxy for plant production variability, it was crop yield indices that more effectively predicted population change in voles. These results suggest that the relative importance of direct and indirect effects of winter climate on herbivores may be related to their body size, the major determinant of above ground/snow or subnivean/fossorial mode of life. [ABSTRACT FROM AUTHOR]

We studied a population of the Red-winged grasshopper Oedipoda germanica, which is a highly stenotypic and endangered species in Central Europe. The locality studied is completely isolated and at the northern limit of this species distribution (north-west of the Czech Republic). We used capture-mark-recapture in 3 consecutive years (2008-2010). We estimated the total population size using POPAN software to be 136 adults in 2008, 70 in 2009 and 122 in 2010. Estimated daily survival rate (Ф) ranged from 0.950 to 0.987. We constructed linear mixed models to test for apparent survival in relation to temperature data. Temperatures (i.e. mean air temperature and maximum air temperature) were found to have significant effects on survival. The population studied is small, isolated and thus threatened by extinction, as are other O. germanica populations at the northern limit of their distribution. The preservation of indigenous populations in their localities can be achieved by active management, including the removal of shrubs and trees. [ABSTRACT FROM AUTHOR]