rss_2.0Raptor Journal FeedSciendo RSS Feed for Raptor Journal Journal Feed, abundance, and breeding of the imperial eagle () in Western Slovakia in 1977–2022<abstract> <title style='display:none'>Abstract</title> <p>The distribution, abundance, breeding success, and habitats of the imperial eagle in the mountains and adjacent lowlands of Western Slovakia were studied over the last 45 years (1977–2022), with a total of 65 breeding pairs documented. Of the 589 breeding attempts (range 2–42 per year) that were recorded, 420 were successful (74%) and produced 718 chicks altogether. Breeding success varied considerably across the years, with an average of 1.2 chicks per initiated and 1.7 chicks per successful breeding attempt. Three chicks fledged from 10.7% of the successful breeding attempts, two chicks from 50.2%, and one chick from 39.1% of them. Breeding numbers increased slowly between 1977 and 1997, with a marked increase after 1998. In two of the most recent years, 2020 and 2021, breeding numbers more than doubled. Since 2000, we have observed changes in breeding habitat preferences, where the population has shown more preference for lowland regions than mountains. Natural factors are probably driving the upward population trend, but there has also been action taken with several management measures. The conservation measures involved and their impact on population and range trends are analysed and discussed here.</p> </abstract>ARTICLEtrue sweetens the beans: evidence of opportunistic feeding behaviour of the little owl (, Scopoli 1769) from Peloponnese, Greece<abstract> <title style='display:none'>Abstract</title> <p>The little owl (<italic>Athene noctua</italic>) is a common raptor in Mediterranean habitats. To acquire more information on its diet, this study identified cranial and post-cranial skeletal material from 70 owl pellets collected during the 2016 and 2017 breeding seasons. The material was used to quantify the little owl’s relative prey abundance using MNI (minimum number of individuals), a taphonomical unit. This study is the first to examine the diet of the little owl in the Peloponnese (southern Greece). After examining 3,691 isolated skeletal and exoskeletal remains from the processed pellets, a total of 78 and 108 prey items were recorded for the two consecutive years. This study, in congruence with previous research, showed that in both years the little owl favoured primarily small mammals and arthropods, with a clear predominance of Thomas’s pine vole (<italic>Microtus thomasi</italic>) and arthropods from the class Diplopoda. Finally, a redundancy discriminant analysis (RDA) was applied to our two-year results, along with those from similar studies in the Mediterranean region, to examine the relationship between habitat types and prey taxa, which supported the little owl’s opportunistic feeding behaviour, depending on variation of ecological factors.</p> </abstract>ARTICLEtrue composition of the long-legged buzzard () in southeastern Bulgaria<abstract> <title style='display:none'>Abstract</title> <p>During 2018–2022, the local breeding population of the long-legged buzzard (<italic>Buteo rufinus</italic>) in southeastern Bulgaria was monitored in the territory of three districts of Sliven, Yambol and Burgas. Diet data were collected in 15 breeding pairs. Overall, we identified 290 prey items. We used three methods for diet analysis that produced different results: (1) collecting prey remains (68 individuals, 23.5%), (2) collecting pellets and skeletal materials (42 individuals, 14.5%), and (3) collecting data on a diet using trail cameras (180 individuals, 62.1%). The dominant part of the diet formed mammalian species (69.3%, ten species and some undetermined Rodentia and other Mammalia). Birds were less represented but with similar species richness (21.0%, 11 species and pigeons (<italic>Columba</italic> sp.), thrushes (<italic>Turdus</italic> sp.), undetermined Passeriformes and Galliformes). Compared to birds, the proportion of Reptilia was lower (9.3%, two species). Amphibia were represented only with one specimen of the common toad (<italic>Bufo bufo</italic>). The dominant diet of long-legged buzzards in southeastern Bulgaria was European souslik (<italic>Spermophilus citellus</italic>, 31.0%), followed by sibling vole (<italic>Microtus mystacinus</italic>, 25.5%). Less abundant taxa were undetermined Passeriformes (6.9%), lesser mole rat (<italic>Nannospalax leucodon</italic>, 5.9%), pigeons (4.5 %), blotched snake (<italic>Elaphe sauromates</italic>, 3.8%), Balkan green lizard (<italic>Lacerta trilineata</italic>, 3.5%), European hare (<italic>Lepus europaeus</italic>, 3.1%), common magpie (<italic>Pica pica</italic>, 2.8%), Colubridae (1.7%), common blackbird (<italic>Turdus merula</italic>, 1.4%), domestic chicken (<italic>Gallus gallus domesticus</italic>, 1.0%) and Eurasian skylark (<italic>Alauda arvensis</italic>, 1.0%). <italic>Spermophilus citellus</italic> was the most abundant species in the Yambol district samples and the most abundant species in the data obtained from trail cameras. In the Burgas district, the dominant species was <italic>Microtus mystacinus</italic>. When comparing the diet spectrum of <italic>Buteo rufinus</italic> from other authors, birds occurred more frequently than reptiles in our material.</p> </abstract>ARTICLEtrue variation in the peregrine falcons () diet after the extinction of the original population and the emergence of a new population in Slovakia<abstract> <title style='display:none'>Abstract</title> <p>We made an analysis of the osteological remains of prey that had been captured by the peregrine falcon (<italic>Falco peregrinus</italic>) and was collected from eyries perched high in rocky cliffs of Slovakia. Birds dominated the 7,233 vertebrates identified (class Aves, with minimum of 98 species and 97.2% of the total). Bones from mammals (class Mammalia, 24 species, 2.5%) were rarely found, and sporadic remains from lower vertebrate species (classes Amphibia, Reptilia, Pisces, 0.3%) were also noted. The collected specimens were divided over three distinct periods. Before domestic pigeons became a major component in the juvenile peregrine falcon diet (Period A), wild pigeons and doves were the most common prey; specifically stock doves (<italic>Columba oenas</italic>) caught at lower elevations, and wood pigeons (<italic>Columba palumbus</italic>) in mountainous areas. The Eurasian woodcock (<italic>Scolopax rusticola</italic>) was a frequent prey . The diversity of peregrine falcon diet reached its maximum between the 1930s and the 1950s (Period B), with the domestic pigeon (<italic>Columba livia domestica</italic>) present in the diet at a similar abundance (16.1%) to wild pigeons and doves. The peregrine falcon population tailed off in the 1960s as pesticides became more commonly used in agriculture. A new population started expanding from Western Europe during the 1990s and has stabilised at around 150 breeding pairs in recent years. Since the turn of the millennium (Period C), domestic pigeons have become the dominant prey (51.1%) along with smaller songbirds such as hawfinches (<italic>Coccothraustes coccothraustes</italic>) and common starlings (<italic>Sturnus vulgaris</italic>), at 15.5% and 14.6% of total osteological remains collected, respectively.</p> </abstract>ARTICLEtrue second egg in the lesser spotted eagle () clutch as a nesting insurance<abstract> <title style='display:none'>Abstract</title> <p>Over an interval of 16 days, two eggs were laid by the same lesser spotted eagle female in her nest in the west-central Slovakia in 2021. The first egg failed to hatch, and the female ate it on the 45th day after she had laid it. Thereafter, the chick hatched from the second egg and later successfully fledged. The case contributes toward explaining why the species lays a second egg, even though the younger hatched chick is almost always prone to siblicide. In this case, the second egg acts as a reserve or an insurance if the first egg should not hatch, enabling the parents to breed successfully.</p> </abstract>ARTICLEtrue hawk () hit by an oncoming vehicle while capturing a striped snake ()<abstract> <title style='display:none'>Abstract</title> <p>One of the most apparent origins of biodiversity loss caused by humans is infrastructural development of roads. Yet they offer certain benefits for some animals, such as hunting opportunities with lower energy costs and consumption of carrion earlier hit by vehicles. Raptors find roads a particularly favorable environment, perching on poles or overhead cables and waiting to attack their prey as it crosses a road. This paper describes the first ever recorded predation by a roadside hawk (<italic>Rupornis magnirostris</italic>) of a striped snake (<italic>Lygophis anomalus</italic>) supportable by material evidence, when both the raptor and the snake were hit by a vehicle immediately after the snake was caught. The study contributes to knowledge about the roadside hawk’s diet and illuminates the problem these human infrastructures pose for animals. Future research on roads birds of prey use as hunting sites could contribute toward improvements in conservation programs for birds of prey species.</p> </abstract>ARTICLEtrue of raptor and owl ringing in Slovakia in 2020<abstract> <title style='display:none'>Abstract</title> <p>In 2020, 1296 raptors and owls (23 species) were ringed in Slovakia. The most abundant was the common kestrel (719 individuals), then the western marsh harrier (126) and saker falcon (92). The proportion of nestlings among all the ringed individuals was 76.7%. In the given period, 145 recoveries of raptors and owls (15 species) were recorded in the Bird Ringing Centre database. This number included 77 recoveries of colour-marked individuals recovered in our territory. There were 43 recoveries of birds ringed in Slovakia and resighted abroad. The last 25 recoveries were of individuals ringed abroad and recovered in Slovakia. In summary, most of the recoveries (of all types) were of red-footed falcon (69 recoveries), then common kestrel (17) and eastern imperial eagle (15). Most of the recovery circumstances were ring reading (almost 76% in total), findings of bird cadavers (6%) and recaptures (5%). Electrocutions and predations by other animals (3% each) were frequent causes of their deaths.</p> </abstract>ARTICLEtrue dependence period, dispersal movements and temporary settlement areas in saker falcons ()<abstract> <title style='display:none'>Abstract</title> <p>Information on mortality rates and their causes in raptors and owls during the post-fledging dependency period (PFDP) and subsequent dispersal is essential for their more effective protection, including more efficient use of funds. Despite the importance of the above data, these data are not yet available for most birds of prey. The study aimed to provide and expand the knowledge in this field for saker falcon. We used satellite telemetry to monitor a total of six young birds since they left the nest boxes. All young birds survived the PFDP, but none survived to adulthood and died during the period of dispersal movements. The PFDP lasted 47 days (median value hereinafter), and the distance of individuals from the nest boxes during this period was 3.2 km (maximum distance 9 km). The area of the home range of the PFDP calculated by the 100% minimum convex polygon (MCP) method was 81 km<sup>2</sup>. During the period of dispersal movements, the monitored individuals set up five temporary settlement areas with an area of 422 km<sup>2</sup> according to 100% MCP, where they stayed for 37 days. All individuals’ mean length of movement routes throughout the monitoring period was 3862 km. The main finding of the present study is the fact that none of the monitored individuals survived the dispersal period. At least half of them died due to human activity (electrocution, hunting), which is probably unbearable in the long term for wild populations of most animal species. This shows the need to start eliminating all types of artificial traps (e.g., electrocution, hunting, poisoning, etc.) without delay, thus helping to prevent the decline of populations of many species in the shorter or longer time horizon.</p> </abstract>ARTICLEtrue Trend in an isolated population of the red-footed falcon () at the edge of its breeding range (south-western Slovakia)<abstract> <title style='display:none'>Abstract</title> <p>Table 1 in original paper (Slobodník et al. 2017, Slovak Raptor Journal 11: 83–89) was published with incorrect data. Correct version is published here.</p> </abstract>ARTICLEtrue and temporal changes in the diet composition of the Eurasian eagle-owl () in Slovakia comparing three historical periods<abstract> <title style='display:none'>Abstract</title> <p>The author evaluates his own data on the food of the Eurasian eagle-owl (<italic>Bubo bubo</italic>) in Slovakia using material he collected between 1975 and 2020. A total of 105,543 food items were identified in 254 samples taken at 136 localities. Mammals had the highest representation (Mammalia, 65 species, 58.4%), and the species composition of birds was diverse (Aves, minimally 140 species, 8.5%), but the common frog (<italic>Rana temporaria</italic>, 32.0%), from the lower vertebrates, is represented more abundantly. Invertebrates (Evertebrata, 0.1%) occurred in food residues only occasionally. The bulk of the samples were collected from eagle-owl nests. The samples were divided into three time periods (A–C), which differ in the manner of human land-use management: A up to the 1950s, with a smaller area of field plots and more extensive grazing in the uplands; B from the 1950s to the 1980s, during the Socialist period, with the concentration of agricultural production in large units; C the last 30 years, 1990 to 2020, with the gradual break-up of collective land management. The first period (A) is characterised by a strong dominance of frogs, particularly the European brown frog <italic>R. temporaria</italic> (44.6%), and a large share of small mammal species of the family Muridae (genera <italic>Apodemus</italic> and <italic>Mus</italic>). During the time of Socialism (B), eagle-owls adapted to hunting larger species of mammals and birds, and the share of frogs in their food fell by half (<italic>R. temporaria</italic>, 23.3%). With the decline in livestock production after 1990 (period C), the species diversity of birds increased: aquatic species and raptors in particular are on the rise. Successive overgrowth of pastures in the submontane zone is reducing the hunting territories of eagle-owls. The dominance of the common vole (<italic>Microtus arvalis</italic>) in their diet has gradually increased from period A (26.8%) to period C (37.3%). Data from eleven areas around Slovakia are evaluated separately for the three time periods. In period A, the highest proportion of frogs was in the Liptov region (<italic>R. temporaria</italic>, 68.2%), when eagle-owls nested deeper in the mountains. The proportion of frogs decreased towards lower areas, and in the Ponitrie (Nitra river basin) it was only 10.8%. At the same time, the share of <italic>M. arvalis</italic> and larger prey increased. A similar trend of increasing shares of larger prey towards lower locations also applied during the Socialist period (B). In the last 30 years (C), frogs in the higher river basins have given way to European water voles <italic>Arvicola amphibius</italic> and <italic>M. arvalis</italic>. In association with the progressive overgrowth of pastures, forest species such as the yellow-necked mouse (<italic>Apodemus flavicollis</italic>) and bank vole (<italic>Myodes glareolus</italic>) are increasingly prevalent, as are the white-breasted hedgehog (<italic>Erinaceus roumanicus</italic>) and various thrushes (<italic>Turdus</italic> sp.).</p> </abstract>ARTICLEtrue ecology of a nesting population of the Common Buzzard () in the Upper Nitra Region, Central Slovakia<abstract xml:lang="en"><title style='display:none'>Feeding ecology of a nesting population of the Common Buzzard (<italic>Buteo buteo</italic>) in the Upper Nitra Region, Central Slovakia</title><p>During routine checks of the nests of the Common Buzzard in the Upper Nitra region (Central Slovakia) we collected food remains and recorded all prey given to the nestlings. We present results from the period 2006-2008. 606 food items were determined, comprising mainly mammals (67%). Birds were also frequent (17%), less so amphibians and reptiles (7%) and invertebrates (10%). During the rodent population peak in 2007, Buzzard pairs nesting in the valley preyed mainly on <italic>Microtus arvalis</italic>, whereas pairs living at the rim of the valley fed on <italic>Myodes glareolus</italic> and <italic>Talpa europaea</italic>, and higher in the Vtáčnik Mts birds fed on <italic>Apodemus flavicollis.</italic> After a massive decline in the rodent population in the following year 2008, the survival rate of the nestlings was very low and the proportion of invertebrates in their diet increased. Birds that were most frequently preyed upon included juvenile <italic>Turdus philomelos</italic> and <italic>Garrulus glandarius</italic>, prey identified from amphibian was mainly <italic>Bufo bufo</italic>, and from reptile prey was largely <italic>Anguis fragilis.</italic></p></abstract>ARTICLEtrue breeding of the Long-eared Owl () in South-Western Slovakia<abstract xml:lang="en"><title style='display:none'>Winter breeding of the Long-eared Owl (<italic>Asio otus</italic>) in South-Western Slovakia</title><p>On February 9, 2005, 3 juveniles of the Long-eared Owl <italic>Asio otus</italic> aged 14-18 days were observed in the urban area of Trnava. During the same period, breeding of the Long-eared Owl was reported from the Czech Republic and Italy. Winter breeding probably occurs more frequently with this species than anticipated, but has so far escaped our attention.</p></abstract>ARTICLEtrue Food of the White-tailed Sea Eagle () at Lake Baikal, East Siberia<abstract xml:lang="en"><title style='display:none'>The Food of the White-tailed Sea Eagle (<italic>Haliaeetus albicilla</italic>) at Lake Baikal, East Siberia</title><p>A long-term study (1991-2001) of the food of White-tailed Sea Eagles in the Svâtoj Nos wetlands at Lake Baikal, Northeastern Russia, revealed that these eagles feed predominantly on water birds, mainly ducks. Anecdotal data from the Selenga Delta in Southeastern Lake Baikal indicate that White-tailed Sea Eagles generally prefer birds as their prey in the Lake Baikal area.</p></abstract>ARTICLEtrue of the Barn Owl () in the Eastern Mediterranean<abstract xml:lang="en"><title style='display:none'>Food of the Barn Owl (<italic>Tyto alba</italic>) in the Eastern Mediterranean</title><p>The composition of the Barn Owl (<italic>Tyto alba</italic>) diet analysed from pellets collected in several regions of the Eastern Mediterranean is presented. In total, 27 samples from 21 sites in S Italy, S Greece (incl. Crete), S Turkey, NW Syria, SW Lebanon, N Israel, and N Egypt were composed of 8842 prey individuals. Mammals represented the dominant part of the prey (90% of the identified prey individuals, comprising 44 species). Birds were less abundant (7%), however, their diversity was enormous (64 species). Amphibians and reptiles were rarely represented in the diet (0.9%), while invertebrates we found more often (2.2%). The relative abundance of particular prey items in the Barn Owl diet was analysed in four geographical regions: (a) SE Europe (Calabria, Peloponnese, Crete), (b) Levantine parts of Turkey and Syria, (c) Lebanon and N Israel, and (d) N Egypt. In complex evaluation of the sample set, endemic forms composed a special group of prey items: <italic>Microtus savii, Sorex samniticus</italic>, and <italic>Talpa romana</italic> in Calabria; <italic>Microtus thomasi</italic> in Peloponnese; <italic>Acomys minous</italic> in Crete; and <italic>Gerbillus amoenus</italic> in Egypt. Another group of prey is represented by typical Levantine species: <italic>Microtus guentheri, Meriones tristrami, Apodemus mystacinus</italic>, and <italic>Rana ridibunda. Apodemus flavicollis</italic> and <italic>Crocidura leucodon</italic> were more abundant in Calabria while less abundant in the Levant. Synanthropic mammals (<italic>Mus</italic> spp., <italic>Rattus rattus, Suncus etruscus, Crocidura suaveolens</italic>) and birds (<italic>Passer domesticus</italic>) represented a significant part of the diet in the majority of the studied area.</p></abstract>ARTICLEtrue / Oznam<abstract xml:lang="en"><title style='display:none'>Announcement / Oznam</title></abstract>ARTICLEtrue to the knowledge on the synanthropization and dietary specialization of the Ural Owl () in urban environment of Košice city (East Slovakia)<abstract xml:lang="en"><title style='display:none'>Contribution to the knowledge on the synanthropization and dietary specialization of the Ural Owl (<italic>Strix uralensis</italic>) in urban environment of Košice city (East Slovakia)</title><p><italic>S. uralensis</italic> is a typical silvatic species, specialized for this life style through its biology and diet. Synanthropization is a rare phenomenon in this species, reflected in the changes of diet and hunting strategies, adapting to the characteristics of the urban environment. Between November 22, 1993 and June 2, 1994, an individual of the Ural Owl was observed 39 times in the urban areas of Košice city. The examination of the pellets revealed that the Ural Owl specialized in hunting <italic>Streptopelia decaocto</italic> (76.7%) and <italic>Columba livia</italic> f. <italic>domestica</italic> (13.4%). These results were confirmed by observations of <italic>S. uralensis</italic> hunting <italic>S. decaocto.</italic> This discovery is the first direct evidence of <italic>S. uralensis</italic> diet adaptation to <italic>S. decaocto</italic> and feral <italic>C. livia</italic> f. <italic>domestica</italic> in Slovakia.</p></abstract>ARTICLEtrue on raptors and owls ringing in Slovakia in 2007 and 2008<abstract xml:lang="en"><title style='display:none'>Summary on raptors and owls ringing in Slovakia in 2007 and 2008</title><p>This article provides brief information about the number, species and reports about ringed raptors and owls in Slovakia during the period 2007-2008. It is a continuation of similar results of the ringing of raptors and owls in the periods 2002-2004, 2005-2006. In 2007, from 1346 individuals of raptorial birds, 941 raptors and 405 owls of 24 species (16 species of raptors and 8 species of owls) including 805 raptors' and 218 owls' nestlings were ringed. In 2008, a total of 856 individuals were ringed, including 542 raptors and 314 owls of 25 species (15 species of raptors and 10 species of owls) including 421 raptors' and 113 owls' nestlings. Also in 2008, the number of ringed raptors and owls decreased by 36.4% in comparison to 2007.</p></abstract>ARTICLEtrue structure of the Imperial Eagle () population in Slovakia<abstract xml:lang="en"><title style='display:none'>Genetic structure of the Imperial Eagle (<italic>Aquila heliaca</italic>) population in Slovakia</title><p>The distribution of the Imperial Eagle (<italic>Aquila heliaca</italic>) in the Carpathian Basin is not continuous, since western and eastern breeding pairs are separated by 150 km from each other in Slovakia, and 70 km in Hungary. In the present study our aim was to examine whether this geographical distance has resulted in any genetic separation between the Western and Eastern Slovak breeding groups. We have used 132 shed feathers and 128 blood samples collected in the fields geographically representing the whole of the Slovak breeding population, and included all juveniles ringed between 2004 and 2006. After successful DNA extractions we have determined the sex, microsatellite DNA-profiles and mtDNA control region haplotypes of the specimens. Data were integrated in a common Hungarian-Slovak "DNA-fingerprint" database, making identification of the same specimen possible when recaptured. Based on a subsample of the collected individuals, the genetic structure of the Slovak population was tested using ten microsatellite loci and mtDNA control region haplotypes, and marginally significant genetic differentiation was found between western and eastern subpopulations. These results suggest that, in spite of the large dispersal capacity of the species, a relatively small geographic distance can also decrease the exchange rate of individuals between subpopulations. As this result involves only samples from the northern part of the breeding area, major conclusions concerning genetic structure and gene flow of Imperial Eagles in the entire Carpathian Basin population cannot be drawn without sampling and analysing the southern subpopulations in Hungary.</p></abstract>ARTICLEtrue in the nests of the Common Kestrel ()<abstract xml:lang="en"><title style='display:none'>Arthropods in the nests of the Common Kestrel (<italic>Falco tinnunculus</italic>)</title><p>In 2008 we analyzed nest material from 25 nests of the Common Kestrel nesting in the residential and rural areas of Bratislava. 4486 arthropod individuals were determined, belonging to the orders Coleoptera, Mesostigmata, Prostigmata, Astigmata, Oribatida, Diptera and Siphonaptera. The arthropod fauna in the nests of the Common Kestrel can be classified into 4 groups: mites, dipteran larvae, adult beetles and dipterans. Three families of avian ectoparasites were present, comprising 26% of the total arthropod abundance. The remaining 74% of arthropod abundance in the nests comprised coprophagous and nidicolous species.</p></abstract>ARTICLEtrue review: Poprach K 2008: Sova pálená [Barn Owl]. Tyto<abstract xml:lang="en"><title style='display:none'>Book review: Poprach K 2008: Sova pálená [Barn Owl]. Tyto</title></abstract>ARTICLEtrue