Abstract The paper describes the observation in Belarus of an adult greater spotted eagle breeding female pale morph “fulvescens”, which retained the same light colour of plumage for five successive years. The data on the presence of pale morph adult birds in the collections of some zoo museums is also analysed.
{"title":"Greater spotted eagles (Clanga clanga) pale morph “fulvescens” breeding during five consecutive years","authors":"V. Dombrovski","doi":"10.2478/srj-2023-0003","DOIUrl":"https://doi.org/10.2478/srj-2023-0003","url":null,"abstract":"Abstract The paper describes the observation in Belarus of an adult greater spotted eagle breeding female pale morph “fulvescens”, which retained the same light colour of plumage for five successive years. The data on the presence of pale morph adult birds in the collections of some zoo museums is also analysed.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80866908","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Meyburg, T. Mizera, G. Maciorowski, D. Karelus, C. Meyburg, M. McGrady
Abstract Using global position system (GPS) technology, we tracked an adult female greater spotted eagle (Clanga clanga) on its wintering grounds in the Sudan-South Sudan borderland during 2005–2015. There were 10 909 GPS locations for this bird in the non-breeding range. Throughout the study, the eagle showed fidelity to its wintering grounds. The non-breeding season coincided with the dry season. The median arrival date was 11 October (n = 10). The median departure date (n = 10) was 4 March, and was less variable than the arrival date. The 95% kernel density estimate (KDE) for all years was 33 838 km2, and the 50% KDE encompassed 6 585 km2. The wintering range was split between two areas, west and east, with the eagle typically arriving in the western area, where it stayed for some time. It then moved about 330 km to the eastern area, where it would remain for a few weeks before departing for Europe in the spring. In both the western and eastern subareas, the annual home ranges overlapped to a variable extent (14–99%). The high degree of fidelity to the wintering grounds shown by this bird was mirrored by the behaviours of two other adult greater spotted eagles that we tracked (using >1 tracking devices) for 15 years that wintered in South Sudan and Turkey. The number of greater spotted eagles that winter in Africa is a matter of speculation, although virtually all individuals are likely to pass through a narrow corridor near Suez, Egypt. Collectively, these tracking data and the findings of other studies suggest that greater spotted eagles from the western parts of the European breeding range often move to Africa. Further, the Sudd wetlands in South Sudan are important for greater spotted eagles and other rare bird species during the non-breeding season.
{"title":"Ranging behaviour of an adult female greater spotted eagle (Clanga clanga) wintering in Sudan for 10 years, as revealed by satellite telemetry","authors":"B. Meyburg, T. Mizera, G. Maciorowski, D. Karelus, C. Meyburg, M. McGrady","doi":"10.2478/srj-2023-0005","DOIUrl":"https://doi.org/10.2478/srj-2023-0005","url":null,"abstract":"Abstract Using global position system (GPS) technology, we tracked an adult female greater spotted eagle (Clanga clanga) on its wintering grounds in the Sudan-South Sudan borderland during 2005–2015. There were 10 909 GPS locations for this bird in the non-breeding range. Throughout the study, the eagle showed fidelity to its wintering grounds. The non-breeding season coincided with the dry season. The median arrival date was 11 October (n = 10). The median departure date (n = 10) was 4 March, and was less variable than the arrival date. The 95% kernel density estimate (KDE) for all years was 33 838 km2, and the 50% KDE encompassed 6 585 km2. The wintering range was split between two areas, west and east, with the eagle typically arriving in the western area, where it stayed for some time. It then moved about 330 km to the eastern area, where it would remain for a few weeks before departing for Europe in the spring. In both the western and eastern subareas, the annual home ranges overlapped to a variable extent (14–99%). The high degree of fidelity to the wintering grounds shown by this bird was mirrored by the behaviours of two other adult greater spotted eagles that we tracked (using >1 tracking devices) for 15 years that wintered in South Sudan and Turkey. The number of greater spotted eagles that winter in Africa is a matter of speculation, although virtually all individuals are likely to pass through a narrow corridor near Suez, Egypt. Collectively, these tracking data and the findings of other studies suggest that greater spotted eagles from the western parts of the European breeding range often move to Africa. Further, the Sudd wetlands in South Sudan are important for greater spotted eagles and other rare bird species during the non-breeding season.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89111141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Mikkola, Esko Rajala, Ü. Väli, O. Keišs, V. Jusys, Z. Kwieciński, V. Dombrovski, Thorsten Krüger, J. Hušek, Samuel Pačenovský, Yuriy Kuzmenko, T. Kuzmenko
Abstract The northern hawk owl is a real irruptive species that respond to irregular changes in the food supply. When prey levels are adequate, it breeds and winters within northern forests. Decreased prey availability can start winter invasions, the timing and magnitude of which are the subject of this study. Mainly the citizen data were extracted from the national bird websites to obtain data on the number of northern hawk owls observed in 2010–22. This paper demonstrates that through citizen data large amounts of information can be collected over wide areas, entire Europe in this case. From Finland to Poland and Czechia the invasions years were very similar, 2013–14, 2017–18 and 2021–22 but in Sweden and Norway three clear irruption years were a year or two before. In Denmark, the clear invasions years were 2013–14, 2016–17 and 2019–20 but Poland, peak years were not at all as clear as in the other countries. The invasions started earliest in Finland in September and peaked in November. In Estonia and Latvia peaks occurred from November to January. In Poland, irruption peaked a month later in December but continued until April like in Finland, Estonia and Latvia. The origin of the irrupting owls in the region has been debated. In Norway, authors are convinced that owls originate from Fennoscandia but this paper indicates that mass invasions have to originate from northern Russia. However, only in Denmark there was one Russian northern hawk owl ring recovery. Further ring recoveries and preferably GPS tagging and satellite tracking of the northern hawk owls are awaited to have a better picture of invasion movements and future conservation needs.
{"title":"The northern hawk owl Surnia ulula invasions in Europe","authors":"H. Mikkola, Esko Rajala, Ü. Väli, O. Keišs, V. Jusys, Z. Kwieciński, V. Dombrovski, Thorsten Krüger, J. Hušek, Samuel Pačenovský, Yuriy Kuzmenko, T. Kuzmenko","doi":"10.2478/srj-2023-0001","DOIUrl":"https://doi.org/10.2478/srj-2023-0001","url":null,"abstract":"Abstract The northern hawk owl is a real irruptive species that respond to irregular changes in the food supply. When prey levels are adequate, it breeds and winters within northern forests. Decreased prey availability can start winter invasions, the timing and magnitude of which are the subject of this study. Mainly the citizen data were extracted from the national bird websites to obtain data on the number of northern hawk owls observed in 2010–22. This paper demonstrates that through citizen data large amounts of information can be collected over wide areas, entire Europe in this case. From Finland to Poland and Czechia the invasions years were very similar, 2013–14, 2017–18 and 2021–22 but in Sweden and Norway three clear irruption years were a year or two before. In Denmark, the clear invasions years were 2013–14, 2016–17 and 2019–20 but Poland, peak years were not at all as clear as in the other countries. The invasions started earliest in Finland in September and peaked in November. In Estonia and Latvia peaks occurred from November to January. In Poland, irruption peaked a month later in December but continued until April like in Finland, Estonia and Latvia. The origin of the irrupting owls in the region has been debated. In Norway, authors are convinced that owls originate from Fennoscandia but this paper indicates that mass invasions have to originate from northern Russia. However, only in Denmark there was one Russian northern hawk owl ring recovery. Further ring recoveries and preferably GPS tagging and satellite tracking of the northern hawk owls are awaited to have a better picture of invasion movements and future conservation needs.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76271903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The nest building and courtship behaviours of the golden eagle are poorly represented in the scientific literature. The paper reports on the first detailed description of building a new nest by a pair of golden eagles. Reciprocal pendulum flight by the pair as part of a pre-breeding courtship display is described for the first time. The “mock attack” between the members of the pair is confirmed to serve the courtship function.
{"title":"A first detailed description of building a new nest and new data on the courtship behaviour of golden eagle","authors":"I. Angelov","doi":"10.2478/srj-2023-0004","DOIUrl":"https://doi.org/10.2478/srj-2023-0004","url":null,"abstract":"Abstract The nest building and courtship behaviours of the golden eagle are poorly represented in the scientific literature. The paper reports on the first detailed description of building a new nest by a pair of golden eagles. Reciprocal pendulum flight by the pair as part of a pre-breeding courtship display is described for the first time. The “mock attack” between the members of the pair is confirmed to serve the courtship function.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77396735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Beak deformities may be permanent or temporary and are caused by various factors. Despite its vast geographical area in India, there has been little research on beak deformities in wild birds, and few cases have been reported. In the present study, we described, as far as we know, the first known report of a beak deformity in the Egyptian vulture (Neophron percnopterus percnopterus) worldwide. On 6 January 2014, the first author (HP) recorded the Egyptian vulture with a heavily deformed bill on the garbage dump in Jorbeed, Bikaner, Rajasthan, India. The causes of the bill abnormality in this individual are unknown, but our record increases the knowledge of the presence of development deformities in Egyptian vultures. We highlight the importance of photographs as a valuable tool for documenting bird beak deformities. In conclusion, we encourage other researchers to report the records of beak deformities, which is necessary for a better understanding of this phenomenon and its insights into the ecological and physiological implications of this condition considerably affecting bird survival.
{"title":"Bill deformities in Egyptian vulture (Neophron percnopterus percnopterus): a noteworthy record from Rajasthan, India","authors":"Hira Punjabi, A. Samson","doi":"10.2478/srj-2023-0007","DOIUrl":"https://doi.org/10.2478/srj-2023-0007","url":null,"abstract":"Abstract Beak deformities may be permanent or temporary and are caused by various factors. Despite its vast geographical area in India, there has been little research on beak deformities in wild birds, and few cases have been reported. In the present study, we described, as far as we know, the first known report of a beak deformity in the Egyptian vulture (Neophron percnopterus percnopterus) worldwide. On 6 January 2014, the first author (HP) recorded the Egyptian vulture with a heavily deformed bill on the garbage dump in Jorbeed, Bikaner, Rajasthan, India. The causes of the bill abnormality in this individual are unknown, but our record increases the knowledge of the presence of development deformities in Egyptian vultures. We highlight the importance of photographs as a valuable tool for documenting bird beak deformities. In conclusion, we encourage other researchers to report the records of beak deformities, which is necessary for a better understanding of this phenomenon and its insights into the ecological and physiological implications of this condition considerably affecting bird survival.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83868504","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract As inhabitants of cavities, some owl species benefit from natural processes, different tree compositions and higher volumes of dead wood. We assumed that protected areas would have a positive impact on the owl community. We compared the abundance of calling owls on 22 lines in managed versus protected forests. Here, we recorded the acoustic communication of owls. The composition of the owl community did not differ between areas. However, we found the impact of forest landscape integrity index and altitude on the diversity of owls. Forests in protected areas probably need time to develop natural and heterogeneous habitat structures. The conservation priority should be to increase the integrity of the forests. Our results also confirmed that managed forests can have a high diversity of owls.
{"title":"Owls’ responses to forest conservation in the Alps","authors":"V. Nemček, B. Kohl","doi":"10.2478/srj-2023-0006","DOIUrl":"https://doi.org/10.2478/srj-2023-0006","url":null,"abstract":"Abstract As inhabitants of cavities, some owl species benefit from natural processes, different tree compositions and higher volumes of dead wood. We assumed that protected areas would have a positive impact on the owl community. We compared the abundance of calling owls on 22 lines in managed versus protected forests. Here, we recorded the acoustic communication of owls. The composition of the owl community did not differ between areas. However, we found the impact of forest landscape integrity index and altitude on the diversity of owls. Forests in protected areas probably need time to develop natural and heterogeneous habitat structures. The conservation priority should be to increase the integrity of the forests. Our results also confirmed that managed forests can have a high diversity of owls.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82761199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Anastasios Bounas, E. Karta, Elisabeth Navarrete, L. Sidiropoulos, H. Alivizatos
Abstract In territorial raptors, breeding performance and foraging behaviour are affected by territory characteristics as the abundance and availability of different prey species varies between habitats. In this study, we examined the diet of two White-tailed Eagle pairs, occupying neighbouring territories in two adjacent inland lakes in Northern Greece. We assess the diet composition of the species in the southernmost part of its European range and evaluate any intraspecific differences in the diet that may reflect resource and/or niche partitioning between territories. We found that birds and specifically waterbirds comprise the largest and quantitatively most important part of the White-tailed Eagle´s diet, with fish being the second most important prey group that was only found in the nest remains from one territory. There was high diet overlap between the two territories and when considering only avian prey our results suggest that the species predates on heavier (and the most common) waterbird species. A main factor that could be driving differences in the abundance and availability of different prey species between territories could be lake physiography, as our results point to a segregation and a subsequent resource partitioning between territories, with each pair utilizing an adjacent lake and its associated habitats. Competition and territoriality therefore seem to be important intraspecific interactions that along with prey availability could promote changes in territory size and ultimately affect individual fitness.
{"title":"Diet composition of White-tailed Eagles inhabiting two adjacent inland lakes in Northern Greece","authors":"Anastasios Bounas, E. Karta, Elisabeth Navarrete, L. Sidiropoulos, H. Alivizatos","doi":"10.2478/srj-2023-0002","DOIUrl":"https://doi.org/10.2478/srj-2023-0002","url":null,"abstract":"Abstract In territorial raptors, breeding performance and foraging behaviour are affected by territory characteristics as the abundance and availability of different prey species varies between habitats. In this study, we examined the diet of two White-tailed Eagle pairs, occupying neighbouring territories in two adjacent inland lakes in Northern Greece. We assess the diet composition of the species in the southernmost part of its European range and evaluate any intraspecific differences in the diet that may reflect resource and/or niche partitioning between territories. We found that birds and specifically waterbirds comprise the largest and quantitatively most important part of the White-tailed Eagle´s diet, with fish being the second most important prey group that was only found in the nest remains from one territory. There was high diet overlap between the two territories and when considering only avian prey our results suggest that the species predates on heavier (and the most common) waterbird species. A main factor that could be driving differences in the abundance and availability of different prey species between territories could be lake physiography, as our results point to a segregation and a subsequent resource partitioning between territories, with each pair utilizing an adjacent lake and its associated habitats. Competition and territoriality therefore seem to be important intraspecific interactions that along with prey availability could promote changes in territory size and ultimately affect individual fitness.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82064214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Maria Kolendrianou, George Mitsainas, Olga Tzortzakaki, Philippos Katsiyiannis, Theodoros Vythoulkas, Myriam Patrou, G. Iliopoulos
Abstract The little owl (Athene noctua) 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 (Microtus thomasi) 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.
{"title":"Hunger sweetens the beans: evidence of opportunistic feeding behaviour of the little owl (Athene noctua, Scopoli 1769) from Peloponnese, Greece","authors":"Maria Kolendrianou, George Mitsainas, Olga Tzortzakaki, Philippos Katsiyiannis, Theodoros Vythoulkas, Myriam Patrou, G. Iliopoulos","doi":"10.2478/srj-2022-0006","DOIUrl":"https://doi.org/10.2478/srj-2022-0006","url":null,"abstract":"Abstract The little owl (Athene noctua) 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 (Microtus thomasi) 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.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78859663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Dravecký, Petar Shurulinkov, Georgi Dilovski, Michal Revický, Girgina Daskalova, J. Obuch
Abstract During 2018–2022, the local breeding population of the long-legged buzzard (Buteo rufinus) 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 (Columba sp.), thrushes (Turdus 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 (Bufo bufo). The dominant diet of long-legged buzzards in southeastern Bulgaria was European souslik (Spermophilus citellus, 31.0%), followed by sibling vole (Microtus mystacinus, 25.5%). Less abundant taxa were undetermined Passeriformes (6.9%), lesser mole rat (Nannospalax leucodon, 5.9%), pigeons (4.5 %), blotched snake (Elaphe sauromates, 3.8%), Balkan green lizard (Lacerta trilineata, 3.5%), European hare (Lepus europaeus, 3.1%), common magpie (Pica pica, 2.8%), Colubridae (1.7%), common blackbird (Turdus merula, 1.4%), domestic chicken (Gallus gallus domesticus, 1.0%) and Eurasian skylark (Alauda arvensis, 1.0%). Spermophilus citellus 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 Microtus mystacinus. When comparing the diet spectrum of Buteo rufinus from other authors, birds occurred more frequently than reptiles in our material.
{"title":"Diet composition of the long-legged buzzard (Buteo rufinus) in southeastern Bulgaria","authors":"M. Dravecký, Petar Shurulinkov, Georgi Dilovski, Michal Revický, Girgina Daskalova, J. Obuch","doi":"10.2478/srj-2022-0001","DOIUrl":"https://doi.org/10.2478/srj-2022-0001","url":null,"abstract":"Abstract During 2018–2022, the local breeding population of the long-legged buzzard (Buteo rufinus) 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 (Columba sp.), thrushes (Turdus 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 (Bufo bufo). The dominant diet of long-legged buzzards in southeastern Bulgaria was European souslik (Spermophilus citellus, 31.0%), followed by sibling vole (Microtus mystacinus, 25.5%). Less abundant taxa were undetermined Passeriformes (6.9%), lesser mole rat (Nannospalax leucodon, 5.9%), pigeons (4.5 %), blotched snake (Elaphe sauromates, 3.8%), Balkan green lizard (Lacerta trilineata, 3.5%), European hare (Lepus europaeus, 3.1%), common magpie (Pica pica, 2.8%), Colubridae (1.7%), common blackbird (Turdus merula, 1.4%), domestic chicken (Gallus gallus domesticus, 1.0%) and Eurasian skylark (Alauda arvensis, 1.0%). Spermophilus citellus 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 Microtus mystacinus. When comparing the diet spectrum of Buteo rufinus from other authors, birds occurred more frequently than reptiles in our material.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84404285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract 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.
{"title":"Distribution, abundance, and breeding of the imperial eagle (Aquila heliaca) in Western Slovakia in 1977–2022","authors":"J. Chavko, Leonidas Prešinský, Roman Slobodník","doi":"10.2478/srj-2022-0005","DOIUrl":"https://doi.org/10.2478/srj-2022-0005","url":null,"abstract":"Abstract 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.","PeriodicalId":56343,"journal":{"name":"Slovak Raptor Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88385384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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