Influence of climatic factors on the population dynamics of small mammals (Rodentia, Soricomorpha) on the sites affected by windthrow in the High Tatra Mts

Abstract

Climatic factors and related changes of the temperature, humidity and sunshine demonstrably affect the
population dynamics of small mammals. This complex influence gets more intense in the case of natural and
anthropic disturbances which occurred in the forest ecosystems of the High Tatra Mts in 2014 (wind calamity)
and in 2015 (forest fire). During the period of research in 2005–2015, we were observing successive changes
in the species composition, abundance and spatio-temporal distribution of small mammals on the seven
permanent research areas by using the CMR method. Besides the changes of selected habitat variables, we
were also continually measuring values of meteorological elements (such as air and soil temperature, relative
air and soil humidity, thickness and duration of snow cover). Statistical testing of the thickness and duration
of snow cover proved significant influence of these factors on the population dynamics of small rodents
(Rodentia) and shrews (Soricomorpha). Winters with a thicker snow cover and longer snow periods had
a positive effect on the reproduction and surviving of both taxonomic groups in the subsequent vegetation
season. We have discovered the positive correlation between the temperature and the quantity dynamics of
dominant small rodents while shrews responded to higher temperatures with less spatio-temporal activity.
Gradient analysis of the complex influence of measured meteorological elements proved species-specific
differences in the responses of small mammals to the current and conditions of weather indicated by ecological
requirements of plant species within a specific habitat.