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  • Author: Václav Tomášek x
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Abstract

Animal home ranges are typically characterized by their size, shape and a given time interval and can be affected by many different biotic and abiotic factors. Understanding of animal movements and assessing the size of their home ranges are essential topics in ecology and necessary for effective species protection, especially concerning birds of prey. Using radio-telemetry (VHF; 2.1 g tail-mounted tags) we studied the movements of two Tengmalm’s owl (Aegolius funereus) males during the breeding season 2008 in a mountain area of Central Europe (the Czech Republic, the Jizera Mountains: 50˚ 50’ N, 15˚ 16’ E). We determined their average nocturnal hunting and diurnal roosting home range sizes. The mean hunting home range size calculated according to the 90% fixed kernel density estimator was 251.1 ± 43.2 ha (± SD). The mean roosting home range size calculated according to the 100% minimum convex polygon method was 57.9 ± 15.8 ha (± SD). The sizes of hunting home ranges during breeding in this study coincide with those previously reported by other studies focusing on Tengmalm’s owl males. However, we found the roosting home ranges were smaller in size compared to those previously reported. This result was most probably connected with different habitat structure in our study area, which was severally damaged by air-pollution in the past, thus probably offering fewer suitable hiding-places, for instance from predators. We found the roosting locations were concentrated in the oldest and densest Norway spruce forest patches. We emphasize that these parts of forest stands require the highest possible protection in our study area.

Abstract

In the last decades, large carnivores – the grey wolf (Canis lupus), Eurasian lynx (Lynx lynx) and brown bear (Ursus arctos), and to a certain extent also the wildcat (Felis silvestris) – have increased their distribution ranges throughout Europe. Monitoring of their current distribution and population trends in the Czech Republic is crucial for the effective conservation and elimination of possible conflicts with humans in the future. In the last years, many projects focused on small-scale monitoring of large carnivores were implemented in the Czech Republic and the neighbouring mountain ranges of Slovakia. Using their results, we compiled the dataset from different regions and analysed the recent distribution of large carnivores and the wildcat. The distribution maps are based on verified data on the presence and reproduction in 2012–2016. This is consistent with the standardized methodology used across Europe. The Eurasian lynx was the most widespread of all large carnivore species in the Czech Republic, with the two trans-boundary populations (Carpathian and Bohemian-Bavarian-Austrian) occupying 94 out of 868 squares (10.8%) of the mapping grid of the Czech Republic. Reproduction was confirmed in 46.8% of the occupied squares. The grey wolf occupied 6.8% of the squares in the Czech Republic and its reproduction was confirmed in 10.2% of the occupied squares. Three reproducing packs belonging to the Central European lowland population were confirmed and the area occupied by the species increased three times within the study period. The brown bear occupied 2.8% of the squares of the Czech Republic – the area is restricted to the Carpathians – with no signs of reproduction; its distribution fluctuated heavily during the study period. The wildcat occupied the smallest range of the Czech Republic among the studied species (1.4% of the squares) but its reproduction was confirmed in a trans-boundary area (White Carpathians) at the Slovakian side of the border. The wildcat also significantly increased its range from one to six squares during the study period.