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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 1 00% minimum convex polygon method was 57.9 ± 1 5.8 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 FROM AUTHOR]

Five juveniles of the imperial eagle were tracked during 2011-201 2. Movements were monitored in the western part of Slovakia and in the border area between Austria, Hungary and Slovakia. Three eagles came from the Záhorská nížina Lowlands and the others from the Malé Karpaty Mts and the Podunajská nížina Lowlands. Post-fledging movements were recorded in areas around the nests. Post-fledging areas covered a large territory (minimum convex polygons - 89, 941 , 969 km2). During the postfledging period the eagles carried out exploratory flights (1 2-33 km from the nest). One temporary settlement area (TSA) was identified in the border area between Austria, Hungary and Slovakia (minimum convex polygon - 68 km2). Two eagles with radio transmitters were recorded in this area. In the TSA and the post-fledging areas two habitat categories were dominant: arable land and forests. Heterogeneous agricultural areas were also important in the TSA (8%). [ABSTRACT FROM AUTHOR]

Although unconfirmed reports on the breeding of the eastern imperial eagle exist from as early as in 1 920s, the first confirmed breeding only took place in 1 998. Since then, 1-5 pairs have bred annually, chiefly in the South Moravia region (the Breclav, Znojmo and the Brno-venkov districts). Out of 37 breeding attempts, 26 (i.e. 70%) were successful, with 48 young reared. The paper summarizes some characteristics of the breeding biology (productivity, breeding losses, nesting tree species, nest height, nest turnover, minimum convex polygon of the nests [nesting trees] built by individual pairs) as well as ringing recoveries. Out of 42 ringed chicks, 39 fledged successfully and produced 3 recoveries (Slovakia - 2, Austria - 1 ). Three foreign ringed birds were also sighted in the Czech Republic. The most interesting case is the breeding of a 1 9-year-old female born in eastern Slovakia (distance 336 km), found via a photo of the ring (V. Gahura, 201 3). [ABSTRACT FROM AUTHOR]

During the period 2008-201 3, 32 different breeding territories were occupied by eastern imperial eagles (EIEs). These territories were mainly distributed in two regions: the Dervent Heights/Yıldız Mts. and the area to the north of the Marmara sea coast. The nearest neighbour distance established was 4.2 km. The mean distance between pairs was 1 0.44±2.95 km. The mean value of breeding success for the period 2008-201 3, including 1 07 cases of incubation, was 1 .01±0.1 0. The mean breeding success of birds in the Marmara region (1 .05±0.78) was higher than that in the Dervent Heights/Yıldız Mts. (0.91±0.84). The present study on the diet of the EIE was based on the remains of 582 prey items of at least 70 taxa. Mammals were the most common group (46.5%), followed by birds (32.4%) and reptiles (20.3%). The white-breasted hedgehog (Erinaceus roumanicus) was the most common prey, followed by two tortoises - Hermann's tortoise (Eurotestudo hermanni) and the Greek tortoise (Testudo graeca) - which together accounted for a total of 1 4.4% of the prey caught. The prey species particularly represented in the food spectrum of the studied pairs were: the yellow-legged gull (Larus michahellis), the European souslik (Spermophilus citellus), the chicken (Gallus gallus f. domestica) and the white stork (Ciconia ciconia). These species together accounted for 67.8% of the prey caught. There was a statistically significant difference (Z=2.52, p=0.01 ) in the food preferences of the EIEs in the two studied regions. [ABSTRACT FROM AUTHOR]