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  • Author: Ervín Hapl x
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Abstract

Conservation of European ground squirrel (Spermophilus citellus) has been supported by the LIFE - Nature project “Conservation of Falco cherrug in NE Bulgaria, Hungary, Romania and Slovakia” during the period 201 0-201 4. The project activities were usually focused on EGS reintroduction programmmes with the aim of ensuring the food base for selected species of birds in areas where EGS were the primary historical prey and have become extinct. Reintroduction programmes were carried out at two sites in Slovakia: Piesocná (Moravský Svätý Ján) and Pod Okrúhlou skalou (Tisovec). Together 1 74 individuals were released at Pod Okrúhlou skalou and 284 individuals at the Piesocná target site. Monitoring of both repatriated colonies focused on the natality and distribution area. At both target sites successful hibernation and reproduction have been confirmed. The repatriation date was strongly influenced by weather conditions, especially during the rainy season. It was necessary to cut the grass several times per season, in order to ensure appropriate conditions for individuals’ survival. It was also necessary to protect the individuals against predators. House cats tend to hunt squirrels, which can be considered as the most serious threat at the Piesocná site. Squirrels at the Pod Okrúhlou skalou site were overly attacked by foxes. Intensive care (especially appropriate management of sites and additional feeding) ensured good stability of colonies, their survival and increase

Abstract

Power lines represent an important and increasing worldwide cause of avian mortality due to collisions involving flying birds. One positive and very important fact is that only some parts of potentially dangerous lines are responsible for the majority of killed birds. These sections need to be identified and treated with proper mitigation measures. In this article we present a specially-prepared methodology aimed at classifying power lines according to the risk they present. The identification of power lines with the highest risk of possible bird collision requires easily-accessed biological, technical and landscape information. In addition to analyses of these main inputs, our methodology also evaluates the influence of power line orientation relative to the important migration routes of birds, the effect of nearby tree growth higher than the evaluated power lines, and the complexity of landscape relief. Based on these three additional inputs, it is possible to produce a digitalized map showing with one-meter accuracy the location of power line sections with the high/middle/low mortality risk due to collision for any existing or newly-planned grid. Sections with highest risk should be considered as priority for the implementation of mitigation measures including e.g. installation of bird flight diverters. Our methodology was prepared for 22 kV and 110 kV distribution power lines in Slovakia. It is flexible enough to be applied equally to any geographic conditions and/or bird community, different voltage levels and construction designs of power lines. Our methodology can be applied by ornithologists, nature conservancy organization and power line system operators to implement environmental and cost-effective mitigation measures.

Abstract

Collisions and electrocutions on power lines are known to kill large numbers of birds annually on a global scale. We conducted comprehensive research focused on bird mortality caused by 22 kV and 110 kV distribution power lines in 13 Special Protection Areas in Slovakia. In the period between December 2014 and February 2016, 6,235 km of power lines were inspected twice during two periods (12/2014–03/2015 and 04/2015–02/2016) of field survey. In addition an intensive study was conducted during the second field survey at one-month intervals on power lines identified as the most dangerous for birds to collide with. As a result, 4,353 bird carcasses and bird remains representing 84 bird species and 14 orders were identified. Electrocution was suspected for 76.72% and collision for 23.28% of fatalities. Raptors were associated with 40% of all identified victims of electrocution. Two peaks of incidence were recorded, the first in March with a high rate of electrocutions as well as collisions of swans, pheasants, common blackbirds, ducks and herons, and the second in September predominantly featuring electrocution of raptors, magpies and corvids. We were unable to quantify seasonal patterns of mortality due to the limited sample of repeated mortality surveys resulting from the large grid of inspected power lines. We conducted comprehensive statistical analysis of more than 100 configurations of pylons and calculated their potential risk towards birds. Strong spatial correlation was revealed in the data set. Metal branch pylons and corner pylons with exposed jumper wires passing over the supporting insulators above the cross arms were the most dangerous configuration, accounting for 34.72% of total recorded electrocution fatalities (0.13 carcass/pylon). Cases of electrocution were also recorded for two bird species of major conservation concern in Slovakia: saker falcon (Falco cherrug) and eastern imperial eagle (Aquila heliaca). The results of this study may substantially improve conservation management and policies needed to reduce bird mortality.

Abstract

The aim of this study was to assess bat diversity and particularly, the significance of underground spaces for bats, in the Revúcka vrchovina Mts. We also studied foraging areas of R. euryale and M. schreibersii which form maternity colonies in the respective area. Considering the rich history of mining in the Revúcka vrchovina Mts. and the previously available faunistic data, the presence of yet undiscovered roosts and species was assumed. During a survey of the area in 2012–2014, altogether 248 new mining sites were traced and 16 species of bats were recorded to roost there. Miniopterus schreibersii, Rhinolophus hipposideros, and Barbastella barbastellus were dominant species and the latter two along with Rhinolophus ferrumequinum represented the most widespread species. Three wintering aggregations of Miniopterus schreibersii composed of 3500–5000 individuals each, and a wintering colony of Rhinolophus hipposideros composed of ca. 630 bats belong to the most significant results of the study. The existence of maternity colonies of Miniopterus schreibersii and Rhinolophus euryale was also confirmed in underground spaces in the region. The newly discovered occurrence sites of Miniopterus schreibersii and Rhinolophus euryale that shift the known margins of the species distribution ranges are of high importance. Data from telemetry tracking of these two species show that the territories where the particular individuals forage are rather extensive (>100 km2). According to these findings, practical conservation of the species and their habitats requires international cooperation.