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  • Author: Ján Lipták x
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Abstract

In the course of ten nesting seasons from 1996 to 2005 I observed nesting by hobbies in Eastern Slovakia within a territory of 1000 km2 in the Košice Basin. During this ten-year period 218 nestings were recorded. The average population density was two pairs per 100 km2 in the monitored territory. In certain quadrants with better occupation it was from four to seven pairs per 100 km2. The birds nested more frequently on very high tension (VHT) electricity pylons (126 instances) than in trees (92 instances). They prefer the nests of hooded crows (Corvus corone cornix) (110 cases) and ravens (Corvus corax) (90 cases), and in only 18 cases did they use another nesting solution. When nesting in VHT pylons in the 1980’s they used to make more use of crows’ nests, but at the present time they prefer ravens’ nests to a significant degree.

Eurasian eagle-owl (Bubo bubo) nesting in a nest box on a very high voltage electricity pylon

In 2008 an Eurasian eagle-owl (Bubo bubo) nestled down for the first time in a wooden nest box with dimensions of 80×80×80 cm, installed on a very high voltage electricity pylon in open agricultural landscape near the village of Budkovce on the Východoslovenská rovina plain in Slovakia. Since 2008 it has nested in this nest box every year, raising 1 and 2×3 young. Nesting by an Eurasian eagle-owl in a nest box on a pylon in agricultural land has not previously been recorded in any part of its whole breeding range. An interesting discovery in 2010 was a clutch of four eggs laid by a common kestrel (Falco tinnunculus) found in the corner of the box, despite the fact that the Eurasian eagle-owls female and chicks were in the nest box.

Abstract

In the period between the years 1976 to 2016 we monitored the nesting site distribution of two populations of saker falcon (Falco cherrug) concentrated in the highlands and adjacent lowlands of western and eastern Slovakia. In western Slovakia we recorded nesting by 56 pairs and 514 nestings, and in eastern Slovakia we observed nesting by 32 pairs and 245 nestings. There were similar nesting success rates in both regions, with pairs producing on average 3.2 young in every successful nest. During the monitored period as a whole a total of 1,788 young saker falcons were raised. At the same time all the pairs gradually resettled in the lowlands, and in the new environment the nesting success rate significantly improved (81.1% compared with 57.1 % in the highlands). This change of nesting biotopes was caused by the impacts of intensive exploitation and environmentally inappropriate forest management, with the accompanying excessive disturbance of nesting birds, but at the same time the disappearance of ground squirrel (Spermophilus citellus) colonies led to a change in the food spectrum for the observed saker falcon pairs. We evaluated the falcons’ feeding habits in western Slovakia between the years 1977 and 2016 (49 pairs; 1–17 pairs/year) and in eastern Slovakia between 2009 and 2016 (12 pairs; 1–3 pairs/year). Altogether 17,669 prey items were identified. From 1976 onwards mammals (Mammalia, 19.8%, 24 species) became gradually less represented as a component in the falcons’ diet compared with birds (Aves, 79.9%, 58 species). In areas of western Slovakia we found stable and predominant proportions of domestic pigeons (Columba livia f. domestica) ranging from 52% to 62%. The proportion of pigeons was distinctly lower in eastern Slovakia (31.5%), compensated for by larger shares of common vole (Microtus arvalis), common starling (Sturnus vulgaris), Eurasian magpie (Pica pica) and hooded crow (Corvus cornix). The common starling (9.5%) was a significant prey species in the lowlands of western and eastern Slovakia alike. Mammals were mostly represented by common voles (9.8%), European hamsters (Cricetus cricetus, 5.3%), ground squirrels (2.1%) and hares (Lepus europaeus, 1.6%). Changes over time in the composition of falcons’ prey were also evaluated over five periods in western Slovakia.

Abstract

Building structures are extremely sensitive at influence of outdoor conditions. Most often these are the influence of wind, sunshine, temperature changes of the surrounding and at least the influence of the own or other loading. According to resonance of the structure with the surrounding is coming to vibration and oscillation in relative high frequency interval (0.1 Hz - 100.0 Hz). These phenomena significantly affect the static and dynamic characteristics of structures, their safety and functionality. The paper brings example of monitoring these phenomena. The object of monitoring is the Danube Bridge Apollo in Bratislava, which main steel structure was measured by acceleration sensors with frequency up to10 Hz. The main topic of the paper is the analysis of dynamic behavior of structure using spectral analysis method. The usage of Fourier Transform is described, own frequencies and amplitudes of structure oscillation are calculated.

Abstract

Operation of special equipment is possible in crisis situations. It is because special equipment is designed for operation in non-standard often extreme conditions and situation, it is available, it has a high degree of crossing capability and it is able to provide basic living conditions even in field, e.g. provision of power for hospital, transportation of wounded and injured persons, supplies, medical care in field conditions, delivery of potable and utility water etc. The authors in the paper deal with a possibility to provide electric energy through advanced renewable sources, especially in meeting tasks in areas with no public mains, possible supplies of potable and non-potable water, embedding such assets into mobile systems. The authors in publication summarize results of research within the „Use of renewable sources of energy in practice project“. System of modeling and computer-aided simulation of renewable sources of energy has been proposed within this project. Application of a system for designing of power systems in logistic containers is expected. The knowledge on power balance of logistic containers operated by the SR Armed Forces in missions abroad is summarized in the last chapter of the paper. Experiences with operating the equipment in crisis and extreme conditions have proved a possibility to export and deploy machines and weaponry equipment of the SR Armed Forces into extreme climatic conditions, e.g. out of European conditions etc.

Abstract

From October 201 0 until December 201 4 the LIFE09 NAT/HU/000384 project was implemented in four Special Protected Areas in Slovakia. The recent project was complementary to a previous LIFE project implemented between 2006 and 201 0. Both projects supported regular monitoring of the population of saker falcon and new approaches to conservation of the species. The LIFE09 project helped to increase knowledge about the prey composition and the behaviour of the species. The population was strongly affected in 201 3 by extremely bad weather conditions (1 .79 fledglings/breeding attempt). Although the total number of saker falcon pairs in Slovakia is thought to be higher, 31 pairs were breeding in 201 4. By analysis of the diet (2991 individuals), 47 prey species were identified, from which birds were predominant (80%). More than half of the diet consisted of feral pigeons (Columba livia f. domestica) (59%)