SEASONAL EFFECTS OF LEAD UPTAKE BY SNOW VOLE CHIONOMYS NIVALIS (MARTINS, 1842) IN WEST TATRA MTS.: BONE METAL CONCENTRATIONS AND HEMATOLOGICAL INDICES

Since the mountains often represent a barrier for the pollutants in many regions, the concentrations of toxic elements in the tissues of alpine animals may remain relatively high and do not decrease in the current times. To estimate heavy metal contamination of alpine ecosystems Snow voles (Chionomys nivalis) are very useful monitors. They are small, easy to catch, have a territory of limited range, fairly short life span and they are closely adjusted to their environment The voles were monthly bait-trapped in the West Tatras, the Western Carpathians, Slovakia. The local population was studied at the Brestova mountain chain (49 degree 13'29.43"N; 19 degree 40'46.07"E, 1902 m.a.s.l.). The animals were trapped in September 2009 and from May to November 2010. The global sampling yielded a total of 50 samples (trapped and retrapped individuals). The lead concentrations in the tail vertebrae and the number of micronuclei in peripheral blood were examined. The Pb levels in voles were exceptionally high in overwintering mature animals (16.1 greater than or equal to g g super(-1)dry weight in average) in comparison to young imma-tures (4.3 mu g g super(-1)). Females had significantly higher concentrations of Pb in their bones (13 greater than or equal to g g super(-1)) than males (7.3 greater than or equal to g g super(-1)). Snow vole adults caught in the spring exhibited significantly higher micronuclei frequencies in peripheral blood than immature ones trapped in summer or fall. Given that Pb is bioaccumulated in the diet of voles, this study showed that feeding on winter diet (mosses, lichens) could constitute a major pathway for the entry of Pb into food chain of alpine habitats. The usefulness of Snow voles as biomonitors of environmental contamination in alpine ecosystems was highly recognized.