Tom 28 (2020): Zeszyt 2 (December 2020)

The Long-eared Owl (Asio otus) was chosen as the bird of the year in Hungary by BirdLife Hungary in 2020 to pay more attention to this species. In the present study, we analysed the data collected on the food, changes in the population and the use of the roosting sites of the owls wintering Southeast-Hungary. A total of 4,683 pellets were collected in four winter seasons between 2016 and 2020, of which 5,265 prey animals were identified. We counted the individuals roosting in the winter roosting sites, and from their maximum number we estimated the local population change of the species as well as the success of the breeding. For this, we also used roadkill data from the nearby town, Battonya.

The diet of Long-eared Owls in the study area was similar to that observed in other parts of the Carpathian Basin. The smaller differences were mainly due to the different geographical distribution of different prey species. We also identified some species previously having no or very few data, thus we confirmed their stable presence in the area. Different weather factors within the season did not effect owls’ diet. The most varied diet was found in the warmest, least snowy winter. Comparing the feeding data with the data from the 1960s and 1970s, it can be seen that the proportion of preys changed significantly. The proportion of House/Steppe Mice decreased by an order of magnitude, while that of rats increased by the same amount over time. The most likely reasons for this may be changes in agricultural cultivation or local demographic conditions (depopulation). In the 2018/19 season, the proportion of Common Vole in the pellets was much higher than in any other years, suggesting this year’s gradation of the species. The pellets collected in different roosting sites close to each other typically had the same proportions of prey animals.

The maximum number of birds observed at the roosting sites did not correlate with the weather of the given season, but was probably related to the effectiveness of the previous breeding season.

The population of the species decreased compared to the early 2000’s based on the number of roosting individuals. This may be due to a decline in crow populations. It should be noted, however, that according to both the roadkills in Battonya and the maximum number of the roosting individuals in Kevermes, this drastic decline came to a halt in 2010s.

During winter, Long-eared Owls (Asio otus) usually roost in groups in urban areas, but their nocturnal movement patterns are less known. The aim of our study is to provide insight into the local-scale urban movement habits of Long-eared Owls. Our study was carried out between 2015 and 2019 in the autumn and winter period, by observations in the early evening and by ringing and recapture of owls in the town of Sombor (NE Serbia). We observed owls when leaving the roosting site located in the town centre following the greenery of the larger avenues towards the outskirts. Owls were sporadically observed in densely built areas of the town, narrow streets with less greenery. Ringing and recapture data suggest that owls were closely linked to the green corridors. They probably used these corridors for easier orientation and to prey on birds roosting in trees in the town, such as sparrows (Passer domesticus, P. montanus), Common Blackbirds (Turdus merula) or Fieldfares (T. pilaris) appearing in harsh winters, and sometimes also pigeons.

The habitat selection of Scops Owl Otus scops has not been studied in Hungary so far. The population in the Carpathian Basin can be considered as a range edge population. Yet, studying and conserving breeding population at the edge of the species’ range is important for the evolutionary potential of the species. In the present study, we examined Scops Owl populations situated on both sides of the Hungarian-Slovenian border. Although breeding density is significantly higher in Slovenia than in Hungary, we found no difference in the ecological diversity of the Goričko Nature Park (GNP), Slovenia and Vas County, Hungary. We found that both the proportion and total edge length of dry grasslands and intensively managed mesic grasslands were lower in Hungary. Similarly, market gardens were present in a larger proportion in GNP. These landscape features all indicate that the complex cultivation is still pronounced in GNP, favouring the Sops Owl as less intensive cultivation modes, like rural market gardens and grasslands play a key role in its habitat selection. Points with Scops Owl observations appeared to be closer to settlements than randomly generated points. They also were observed farther from primary roads than from secondary roads. This is in accordance with other studies revealing that these nocturnal birds avoid noisy roads. We briefly discuss why conserving range edge populations is important, and how time and effort optimised species conservation measures should accompany landscape protection at the political level.

In the present study, we analysed the variation of breeding parameters and the diet composition of the Common Barn-owl (Tyto alba) in three different demographic phases of the Common Vole (Microtus arvalis) in a complete population cycle between two outbreaks. The study was conducted in the south-eastern part of the Transdanubian region in South Hungary. For the analysis, we used data of 81 randomly selected first clutches from 2015 to 2019, a time period which represented a full demographic cycle of the Common Vole after the 2014 outbreak with an exceptionally high peak. We tested the impact of prey abundance and diversity of diet composition as continuous predictors as well as the demographic phase of Common Vole and the mesoregion as categorical explanatory variables on the measured reproductive outputs as response variables using Generalized Linear Models (GLM). Considering the breeding parameters, the number of fledglings, and fledging and reproductive success were significantly higher in the increase phase than during the vole crash phase. Based on GLM models, our results demonstrated that the clutch size of the Common Barn-owl is determined ultimately by the availability and consumption rate of the Common Vole as main prey, while other small mammal prey categories did not affect the clutch size. These results support the finding that the clutch size of vole-eating raptors and owls, which begin breeding periods in early spring predicts the vole abundance in this early spring period. Considering the other investigated small mammal prey groups, the alternative prey role was confirmed only in case of the Murid rodent prey categories (Apodemus spp., Muridae).

Over the last decades, the European Hamster (Cricetus cricetus) has been declining in many parts of its European range. Due to the lack of recent information on the occurrence and status of the European Hamster in the south-western Carpathian Basin west of the Danube, we used information gathered from prey remains in Common Barn-owl (Tyto alba) pellets. In spite of considerable sampling effort, we retrieved only few hamster remnants. Two skulls were found in Podolje (Croatia) in 2007 and 2016, respectively. Further five hamsters were retrieved from pellets collected in 2017, 11 km to the northwest in Udvar (Hungary). In Sátorhely, 5 km north from Udvar, one roadkill male was found on 27.07.2019. Testimonies from local inhabitants confirmed the current presence of the European Hamster in the area. Our results suggest the presence of a small isolated population in the border area of Croatia (UTM 10 km grid square CR27) and Hungary (CR18, CR19). This small isolated population is on the south-western limit of the range of the species. We presume that the population requires conservation attention because of its isolated position at the edge of the species’ range, its small size and low abundance. We call for a transboundary action by nature conservation authorities in Croatia and Hungary.

As the whole Palearctic steppe system, its iconic bird, the Great Bustard has also suffered from the expansion of intensive agriculture. The species now typically has stable or growing populations only in protected areas, but negative processes are still prevalent even there. In this study, we present a recent change in a part of the Natura 2000 site designated for the isolated West Pannonian population. In recent years, a total of 2.3 km Center-pivot and laterally moving linear irrigation systems have been built and 4.7 km of underground pipelines have been laid, with which more than 52% of the 1245,5 ha study area was irrigated by 2020. In comparison to 2009, when the study period has started, the sown area of autumn cereals, one of the main breeding habitats, was roughly halved and the proportion of crops unsuitable for breeding was increased. New crops requiring irrigation have emerged with a rate of 30.6% in the last year. Despite the available support, the area of alfalfa, which is the most significant breeding habitat, and is grown almost exclusively in the agri-environmental scheme, has decreased. As a result of habitat degradation, the number of Great Bustard females observed in the area in spring decreased to a small fraction of the beginning. Irrigation farming is expected to increase, as a response to the climate change, but in order to save agro-steppe habitats and their species, the adverse effects of agricultural intensification need to be urgently addressed at both local and European levels.

The transportation infrastructures like railway tracks and roads bear negative impacts on natural environment. However, the opposite effects are also true in some instances where the man-made constructions have positive effect on faunal assemblages. This proposition was justified through the assessment of bird species using railway stations as model man-made structures in an urban-rural gradient, in the suburbs of Kolkata, India. During the entire study period along nine different railway stations, a total of 43 bird species belonging to 12 orders and 26 families were observed. Among these, the order Passeriformes was predominant in its species composition having 18 different species from 11 different families. In urban railway stations, a total of 23 bird species under 22 genera and 14 families were observed. In suburban railway stations, a total of 35 bird species under 32 genera and 22 families were documented. The railway stations from rural region showed the maximum number of species and abundance of bird families, where a total of 36 bird species under 32 genera and 23 families were observed. The railway stations from the suburban and rural regions were more similar in species composition. Irrespective of the locations, during the entire study period, the House Crow (Corvus splendens) was the dominant species followed by the Common Myna (Acridotheres tristis). About 18 bird species exhibited a decreasing population trend observed through the global population trend analysis. In all the railway stations, the abundance of omnivores were dominant while, the number of granivores were higher in the rural regions and the nectarivores were absent in the urban regions. It was apparent that the railway stations bear a positive effect on the bird species assemblages, which can be sustained through proper environmental management planning inclusive of urban greening.

The Cheer Pheasant (Catreus wallichii) is a protected species found abundantly to the west of Kaligandaki River. This study was conducted in the Myagdi district located in the western part of Kaligandaki River from October 2016 to June 2017. Our aim was to assess the habitat and population status of Cheer Pheasant, using acoustic survey and quadrate methods. A total of 38 breeding individuals were estimated in 7 bird/km² density. The study also revealed that Cheer Pheasants showed a preference for exposure components of the habitat. They preferred moderately steep eastern slopes (10–35°) and steep southern slopes (35–67°) between 1800–2400 m elevations. Additionally low tree density and high herbs density showed a significant effect on the habitat choice of the species. Poaching and habitat destruction are the major threats in the study site, calling upon a strategic management plan for the long-term conservation of the Cheer Pheasant.

The Eastern Imperial Eagle is a globally threatened species, represented with not more than 35–40 pairs in Bulgaria. As a facultative scavenger feeding on carcasses and parts of dead domestic and wild animals, this species is extremely vulnerable to poisonous baits and toxic agents, intentionally or accidentally set up in its food. The present study identified electrocution and poisoning as the main mortality factors for the eagles in Bulgaria. We analysed a total of 56 cases among which 44 cases were related to the mortality of non-territorial eagles in different age classes, and we found 12 dead or distressed territorial birds recorded between 1992–2019. The main mortality factor was electrocution, accounted for 30.4% of fatalities. The poisoning was the cause of mortality in 12.5% of the non-territorial and 10.7% of the breeding birds. Some of the cases were laboratory confirmed as intoxication, while the others, based on the history, clinical symptoms and field evidence, indicated poisoning. The most commonly used toxic agents were anticholinesterase’s inhibitors. As a result of a timely therapy applied to the live birds found in distress with symptoms of poisoning, six eagles were successfully treated and released back in the wild. We found that mortality of eagles depended on the age of birds, breeding or dispersal grounds, while season had no significant effect.

The nests of rare and threatened bird and reptile species that breed on the ground are often attempted to be protected from predators with fences, grids, and various repellent materials. Results of some experiments refer to the repellent function of human scent, whereas others suggest that it has an attractive role. We aimed to investigate how effectively ground nests can be protected from predators if human hair is placed around nests. We performed the experiment in a riverine oak-elm-ash forest using 90 artificial nests, each with 1 quail and 1 plasticine egg: 30 nests were protected with a game fence, 30 nests were surrounded with human hair and 30 nests were unprotected (control). During the 24 days, predators damaged 23% of the nests protected by a game fence, 40% of unprotected nests and 47% of the nests surrounded with hair. The daily survival rate of quail eggs in nests protected with a game fence was significantly higher than the ones in the nests surrounded with human hair. Only 18% of the quail eggs and 36% of plasticine eggs were damaged. Such difference can be explained by the fact that small-bodied birds and mammals could pass through the game fence and left traces on plasticine eggs but they were unable to crack the shell of quail eggs. Within the game fence, denser vegetation can provide better nesting conditions and result in greater breeding success. The repellent role of human hair has not been proved, on the contrary, in some cases we have observed signs of its attractant role, such as small-bodied birds took hair away for nest building.

Since urbanization is a worldwide phenomenon, numerous species have gained the advantage of urban ecosystems. The Eurasian Collared Doves (Streptopelia decaocto) has become widespread all across Europe along with human-altered habitats. In general, population levels are stable but numbers have locally decreased in the past few decades. In parallel, a new wave of urbanization came forward, so Wood Pigeons (Columba palumbus) entered urban ecosystems alongside with other Columbidae species. In this paper, our primary goal was to find any connection between habitat availability factors such as coniferous tree density and the population dynamics of two urbanized species. A locally emerging corvid species, the Hooded Crow (Corvus cornix) was also taken into consideration in influencing tree-nesting doves and pigeons as a primary nest predator. During the research period, we aimed to express the differences in habitat structure of two urban ecotypes by nesting tree availability and structure and to prove the power of predator presence in sampling sites. Our results showed that residential areas have a higher proportion of coniferous trees, as well as the high preference of residential areas by Wood Pigeons and Eurasian Collared Doves.

Songbirds are the largest order of birds with 6456 species, making up more than half of every known bird species. The location and time of their emergence, as well as the method of their spreading, is debated. They are present in the Carpathian Basin from the beginning of the Neogene, with an increasing number of types and species. Due to their diverse ways of life and diets, their presence mirrors the environmental conditions of the given geological periods quite accurately.

Thirty-three nest cavities of Green Woodpeckers (Picus viridis) in Hungary were documented over a period of 15 years (2006–2020). Thirteen different tree species were used. All documented cavities were in the main trunks of trees. The mean cavity height was 5.6 m and 1.5 m standard deviation and ranged from 2 to 9 m. Tree trunk diameters ranged between 36–55 cm with a mean of 43.1 cm and 4.2 cm standard deviation. A southerly orientation of cavity entrances prevailed with a mean direction of 187° clockwise from north. The results suggest that cavity-entrance orientation was non-random.

The Lichtenstein’s Sandgrouse (Pterocles lichtensteinii) is a nomadic, mostly nocturnal species. Its world range includes several countries in Africa, as far south as Kenya, and Asia as far east as Pakistan, but within the Middle East, it is a resident in Egypt, Southern Israel and Jordan, Saudi Arabia, Yemen, Oman and Southern Iran. Like other members of its family, it is found in very dry habitats including wadis and stony deserts. Seeing a flock of them in Lebanon is extraordinary. They were sighted for the first time in the country. The dry hot wind in that time of the year might have brought them there. A poacher shot the flock and killed six birds during night hunting.