Raptor Journal Feed

Assemblages of orthopterans, small mammals and birds of prey in areas after conversion from arable land to grassland

Tue, 02 Jun 2026 00:00:00 GMT

Intensive agricultural management is considered a factor contributing to biodiversity loss, and therefore, there are increasing efforts to convert areas of arable land into extensively used habitats. Our study describes the colonisation process of Orthoptera, Mantodea, and small mammals on land converted to managed permanent grassland, while also assessing the impact on birds of prey abundance. Research conducted between 2021 and 2024 indicated rapid positive responses by the studied taxa, with Site 1 recording 16 Orthoptera and Mantodea and 12 small mammal species, comparable to other natural sites in the Danube Lowlands. No differences were found in Orthoptera abundance and species richness, or small-mammal abundance; however, small-mammal species richness was higher at Site 1. The abundance and species richness of small mammals at both sites exhibited pronounced seasonal variation, peaking in autumn. We found a positive relationship between the abundance of small mammals and the abundance of birds of prey. The birds of prey assemblage was dominated by common buzzard (Buteo buteo), common kestrel (Falco tinnunculus), and western marsh harrier (Circus aeruginosus). Our research underscores the swift adaptability and colonisation capabilities of the studied taxa and suggests that recently converted grasslands can support relatively diverse assemblages of orthopterans, mantids, and small mammals within a few years of conversion. Consequently, these restored habitats provide a critical food supply for birds of prey, mitigating declines in prey abundance caused by intensive agricultural practices in the surrounding landscape.

Migration and wintering of adult European honey buzzards (Pernis apivorus) breeding in Germany, as revealed by satellite telemetry

Tue, 02 Jun 2026 00:00:00 GMT

Twelve adult European honey buzzards (Pernis apivorus) were tracked for up to five years. The females left the breeding area approximately eight days earlier than the males. Ten of the birds appeared to die during the telemetry period. In autumn, all of the birds migrated to West Africa, reaching as far south as the Republic of the Congo via France and Spain. In most cases (13 out of 20 migrations involving nine birds), they crossed the western third of the Pyrenees. Most of them used the Strait of Gibraltar to reach Africa (16 migrations involving 10 birds), but in some cases (three migrations involving two birds) they flew long distances over the Mediterranean sea instead. The routes of individual birds varied from year to year. In spring, the birds generally migrated farther east than in autumn. Three honey buzzards wintered in Nigeria, two in Liberia and one in each of Cameroon, Gabon and the Republic of the Congo. The distances travelled between the breeding grounds and wintering areas ranged from 6,128 km to Liberia to 8,645 km to the Republic of the Congo. The autumn migration lasted between 36 and 99 days, while the spring migration lasted between 23 and 55 days. This depended on the length of the migration route, the duration of stopovers and other factors. Birds travelled up to 600 km per day, reaching a maximum speed of 109 km/h. Winter site fidelity over consecutive years was recorded for four individuals over up to four winters. The home ranges of two wintering honey buzzards were calculated from up to 97 GPS fixes. These birds had small winter home ranges of 1.55 and 3.40 km² (MCP95), and 4.43 and 7.44 km2 (KDE95), respectively.

Post-fledging dependence period, dispersal movements, temporary settlement areas, and causes of mortality in saker falcons from Central Europe

Sat, 18 Apr 2026 00:00:00 GMT

We are currently aware of home-range sizes and mortality rates during the post-fledging dependency period (PFDP), as well as the migration routes and wintering sites of many raptors. In comparison, the period of natal dispersal is significantly understudied, including survival rates and information on the temporary settlement areas (TSA). Despite their importance, these data are unavailable for most raptor species, though they are crucial for more effective species protection and more efficient financing of nature conservation. Using satellite telemetry, we monitored twelve young saker falcons (Falco cherrug) from fledging through the start of dispersal, and continued monitoring until their deaths. None of them died during the PFDP, but only one survived the natal dispersal period, reached adulthood and joined the breeding population. Their PFDP lasted 47 days (median, hereinafter), and they occupied home ranges of 81 and 23 km², calculated using the 100% and 80% minimum convex polygon (MCP) methods, respectively. Monitored individuals exhibited two distinct dispersal movement/behaviour patterns: seven individuals dispersed over long (>500 km) distances, and five others over short (<100 km) distances from their natal areas. During these movements, ten individuals established 21 TSAs. These were occupied for 28 days and covered 981 and 278 km², according to the 100% and 80% MCP, respectively. The finding that only one individual survived to adulthood contrasts with the increasing population trend in Slovakia and may be a consequence of the survival impacts of tagging. However, at least half of all documented mortality was attributable to human-induced causes, including at least one-third of deaths being caused by overhead power lines. This highlights the need to eliminate or at least try to reduce all types of anthropogenic mortality, such as electrocution, hunting, and/or poisoning, as much as possible immediately, if we want to reverse negative population trends in many birds of prey and to preserve them in the long term.

A rare case of melanistic chicks in a Montagu’s harrier nest

Sat, 18 Apr 2026 00:00:00 GMT

We report the discovery of a nest of Montagu’s harrier (Circus pygargus) in northwestern Italy containing three chicks: one normally coloured with white down and two dark morph individuals with grey down. The nest was discovered during wheat harvesting and, because it was left unprotected, the chicks were collected and transferred to a wildlife rehabilitation centre. During captivity, the two grey chicks developed an almost entirely black juvenile plumage. Dark morph individuals are relatively common in Spain but are very rare in other European countries. To our knowledge, dark-morph downy chicks of Montagu’s harrier have been very rarely described and illustrated.

A rare case of brown plumage aberration in the Himalayan vulture (Gyps himalayensis) from Haryana, India

Sat, 18 Apr 2026 00:00:00 GMT

Plumage aberrations in wild birds are well-documented, although underreported in large raptors, especially in high-altitude species such as the Himalayan vulture (Gyps himalayensis). Here, we report a rare case of brown plumage mutation observed in a juvenile Himalayan vulture in Haryana, India. The morphological characteristics are consistent with known descriptions of brown eumelanin-based aberrations, providing valuable insight into pigment anomalies in this species and highlighting the need for systematic documentation of such rare occurrences in wild raptor populations.

First observation of the Amur falcon (Falco amurensis) in Algeria

Fri, 31 Oct 2025 00:00:00 GMT

We report the first record of the Amur falcon (Falco amurensis) in Algeria and throughout North Africa, based on a single individual observed and photographed on 15 July 2025 and again on 3 August 2025 in the Illizi region, southeastern Algeria. The bird was documented using a Nikon Coolpix P900 camera in an open Saharan habitat characterised by sparse desert vegetation. This observation represents a westward extension of the known distribution of the species into the central Sahara. It constitutes a notable case of vagrancy well beyond its typical migratory corridor between eastern Asia and southern Africa. This finding underscores the species’ potential for long-distance dispersal and highlights the importance of continued monitoring for rare migratory birds in arid zones of Algeria or throughout North Africa.

Raptor morbidity, mortality, and post-release survival tracking: rehabilitation outcomes from a wildlife rehabilitation centre in Cyprus

Tue, 16 Sep 2025 00:00:00 GMT

Raptors as apex predators hold an ecologically important position in biological food webs and historically have faced numerous challenges. Wildlife rehabilitation centres provide an opportunity to understand the regional threats to local raptors. This study details the admissions and recoveries of wild raptors admitted to the Wildlife Rescue and Rehabilitation Center in Northern Cyprus between 2016 and 2022. A total of 1,101 raptors were admitted, comprising 22 species and three families, with a mean rehabilitation success rate of 42.6%. The most common species admitted were common kestrels (Falco tinnunculus) (44.1%), little owls (Athene noctua) (22.8%), and western barn owls (Tyto alba) (11.6%). The prevalent causes of admission were trauma (unknown) (27.2%), orphaned/abandoned (22.6%), and collision (11.9%). Post-release survival rates averaged 368 days ± 407 SD (median = 183, range 2–1,177). Six birds [four long-legged buzzards (Buteo rufinus), one European honey buzzard (Pernis apivorus) and one northern goshawk (Astur gentilis)] were GPS tracked following recovery, and their average survival time was 319 days ± 334 SD (median =184, range 18–847, and one still transmitting). Additionally, one Bonelli’s eagle (Aquila fasciata) and four long-legged buzzards were fitted with either a tail-mounted or leg-mounted VHF radio transmitter, which were less successful, with only the Bonelli’s eagle being tracked away from its release site. Post-release survival indicates that the release assessment of individuals is professionally managed, while the rehabilitation success rates demonstrate that the centre is delivering effective treatment and care.

Wintering raptors in lowland farmland of north-western Italy: a second distance sampling survey twenty years later

Tue, 16 Sep 2025 00:00:00 GMT

Diurnal raptors and the great grey shrike (Lanius excubitor) wintering in the lowland farmland of northwestern Italy were surveyed again after 20 years, during the winters of 2020/2021 and 2021/2022. Data were collected using roadside car transects, and perpendicular distances of birds from the transect lines were recorded to estimate wintering raptor densities. Ten species (9 raptors) were observed, but only two species, the common buzzard (Buteo buteo) and the common kestrel (Falco tinnunculus), were recorded frequently enough to allow reliable density estimates. Extensive rice fields in the north-eastern part of the study area supported high densities of common buzzards, with estimates ranging between 1 and 2 individuals per km². Although occurring at lower densities (~ 0.5 individuals per km²), the common kestrel showed a broader habitat tolerance and appeared less dependent on specific agricultural landscapes. The estimated wintering population of common buzzards in the lowland farmland of the Piemonte region, an area covering approximately 5,700 km², was slightly higher than that recorded 20 years earlier, ranging between 4,000 and 5,000 individuals. For the common kestrel, the estimated wintering population in the same area was around 2,500 individuals (1,800–3,500). However, the total wintering populations of both species in the whole region were certainly much larger, because they are also widespread during winter in hilly and mountainous areas. Overall, the results highlighted the importance of rice fields for wintering common buzzards, suggested stability in the raptor community, and advocated for broader adoption of distance sampling methods for effective large-scale bird surveys.

The helminth fauna of the Eurasian goshawk (Accipiter gentilis) in northwest Russia

Tue, 16 Sep 2025 00:00:00 GMT

The challenges in researching the parasite fauna of rare and red-listed species, such as the Eurasian goshawk (Accipiter gentilis), render the study of accidental findings of these birds highly valuable and important. This paper discusses the results regarding the species diversity and occurrence of helminths in the Eusarian goshawk in northwest Russia. In July and September 2024, parasites were collected from the respiratory and gastrointestinal tracts of two birds that had died in the City of Petrozavodsk and the Village of Porosozero. This is the first report of the occurrence of nine helminth species (trematodes Neodiplostomum attenuatum, Srtigea falconis, Prosthogonimus cuneatus and nematodes Cyathostoma americana, Eucoleus dispar, Porrocaecum depressum, Baruscapillaria falconis, Capillaria tenuissima, Microtetrameres sp.) in the Eurasian goshawk, which is actively expanding its distribution in northwest Russia. Karelia is the only region where the trematode P. cuneatus has been found in the Eurasian goshawk. With the new findings, we provide an overview of Eurasian goshawk’s parasite fauna, with reference to available information on other regions of Russia and Europe. A list of 43 helminth species documented for hawks has been compiled using published data. Another important outcome of our study is that, having analysed the birds, we managed to describe the ecological characteristics of the birds adapting to urbanised environments (cities and rural communities). This adaptation likely involves changes in the birds’ dietary spectrum and, accordingly, the species composition and infection rates of their common helminth parasites.

Abundance, taxonomic and functional diversity of raptors along aridity gradient and habitat types in Rajasthan, India

Tue, 16 Sep 2025 00:00:00 GMT

Birds of prey and their community structure can serve as indicators of ecosystem conditions. In this study, we analysed abundance, taxonomic and functional diversity and their variability across different levels of aridity and habitats. We recorded 43 species of raptors belonging to five families of three orders, and their taxonomic diversity was relatively uniform across the aridity gradient and habitat types. Black kite (Milvus migrans) and shikra (Accipiter badius) were the most abundant species across Rajasthan, while the long-eared owl (Asio otus) was the rarest. From the perspective of functional diversity, our findings suggest that the Thar Desert, being the most extreme and dry environment, supports species with specialised traits that allow them to survive harsh conditions. Results also indicate that lifestyle, beak length, tarsus length, and body mass combinations represent unique functional traits influenced by varying climatic (aridity) and ecological conditions (habitats). Understanding these functional relationships is critical for raptor conservation, particularly in arid landscapes where habitat fragmentation and food abundance fluctuations may impact species persistence.

Occurrence of the great black hawk (Buteogallus urubitinga) in the largest urban area of South America

Sat, 24 May 2025 00:00:00 GMT

The great black hawk is widely distributed in South America, including Brazil and the state of São Paulo, but it is uncommon in the region of the city of São Paulo (Grande São Paulo), the largest urban area in South America. We compiled, organized, and analyzed available records of the species for this highly urbanized region in the literature, ornithological databases, and online birdwatching platforms, and produced field data. We obtained 13 records from four locations between 2018 and 2024. All records were associated with humid and flooded environments, mainly artificial reservoirs. The long period without records and the low number of recent detections suggest several possibilities: the species has always been uncommon in Grande São Paulo, perhaps for geographic, environmental, ecological, and/or climatic reasons; the species may be colonizing lakes and reservoirs created in recent decades; or the species is just a regional vagrant bird in Grande São Paulo. Nonetheless, the presence of this hawk in the surroundings of the largest urban area in South America shows the importance of the wetlands and floodplain remnants of the Alto Tietê Hydrographic Basin, which are threatened environments that urgently need protection by the establishment of conservation units.

The first documentation of a juvenile eastern imperial eagle (Aquila heliaca) with an unstreaked body

Sat, 24 May 2025 00:00:00 GMT

An extremely pale juvenile eastern imperial eagle (Aquila heliaca) without the typical dark streaking of the body was observed and photographed wintering in Oman. The bird presented an identification challenge and was initially identified as a tawny eagle (Aquila rapax). The possible overlap in the breeding distribution of both species is discussed, together with the possibility for natural hybridisation.

Case report and prey analysis of ground-nesting eagle owls (Bubo bubo) in Slovakia

Sat, 24 May 2025 00:00:00 GMT

In current ornithological literature, there is a general consensus that the eagle owl (Bubo bubo) is a breeder of rocky habitats in Slovakia, especially on cliffs and quarry walls, but little research to date has concentrated on cases of ground-nesting in the lowland areas of the country. This study provides an overview of the documented cases of eagle owls breeding in lowland forests, a relatively unusual method of breeding for this species. The authors also report a recent case of an eagle owl breeding on the ground in a floodplain forest at the small settlement of Sedín near the forest edge in the western part of the Danube Lowlands. The nest was located in a shallow basin at the base of a large white poplar (Populus alba) tree, just 3 m from an oxbow lake. The site was visited three times between 12 April and 12 May 2024, and three young birds were observed in the nest, all of which likely fledged successfully. Prey remains from the nest were analysed and the results are presented here together with those of five other eagle owl nests from the lowlands of Slovakia and the Czech Republic. In the nest near Sedín, the common hamster (Cricetus cricetus) was the predominant prey species, in contrast to a location near Vojčice in the East Slovak Lowlands in which the brown rat (Rattus norvegicus) predominated or nest sites in Southern Moravia and the Třeboňsko region of the Czech Republic where larger birds were the main prey.

Movement patterns, roosting sites and diet composition during the breeding season of three different forest-dwelling owl species in an area of sympatry: a case study of male home ranges

Sat, 24 May 2025 00:00:00 GMT

In areas of sympatry, animals face risks associated with predation pressure and competition for space and/or food from individuals within the same or different ecological guilds. In birds of prey, intraguild competitors and adversaries may adapt to coexistence through various mechanisms, such as spatial avoidance, dietary differentiation, or using distinct habitat types in the shared environment. However, studies examining multiple sympatric owl species and simultaneously investigating their home ranges, diet, and roosting sites remain exceptional. Therefore, we studied four sympatric owl species to obtain findings on spatial arrangements of their diurnal roosting home ranges, and prey and habitat selection during the breeding season. Individual males from three of the four studied species [Eurasian pygmy owl (Glaucidium passerinum), boreal owl (Aegolius funereus), and tawny owl (Strix aluco)] were radio-tracked in an area co-inhabited by an apex intraguild predator, the Eurasian eagle-owl (Bubo bubo). The diurnal roosting home range, calculated using a 95% kernel density estimation method, was 111, 117, and 7 ha for the pygmy, boreal, and tawny owl male, respectively. The diurnal roosting home ranges overlapped by 55% in the case of the boreal and pygmy owl males; in contrast, their ranges overlapped only by 2% and 4%, respectively, with that of the tawny owl male. The tawny owl male roosted at a respectful distance from the eagle-owl’s nest site in all recorded cases, while it was included within the diurnal roosting home ranges of both smaller owl species, indicating the subordinate owl species may use the presence of an apex predator to protect themselves from medium-intraguild enemies. The study results suggest that intraguild competitors/enemies may mitigate direct conflict through spatial avoidance and dietary differentiation, and such partial niche separation may help reduce food competition within the guild, promoting coexistence among species.

Bird crime and the assessment of risk areas in Slovakia

Fri, 18 Oct 2024 00:00:00 GMT

Bird crime is a serious problem in many countries around the world. This study focuses on the situation in Slovakia, summarising data on bird crime in the country between 2016 and 2022. Over the course of that period, 92 cases were recorded in 27 districts involving 33 animal species. At least 249 protected birds and 78 mammals fell victim to illegal activities, and 61 poisoned baits were discovered. Social value is the monetary value which state institutions use to quantify the damage incurred to wildlife. Slovak law determines whether an illegal act is an offence or a criminal act based on the value of the incurred damage. The total social value of all of the protected animals as a result of illegal activities was estimated at € 696,250. Intentional poisoning, typically using carbofuran, was the most common of illegal act identified in the recorded cases, followed by shooting and trapping. An analysis of the recorded cases of bird crime was also used to assess the risk in each of Slovakia’s districts in relation to landscape structure variables. The percentage share of arable land was found to be a reliable predictor of bird crime, regardless of whether the birds had been poisoned or shot. These findings can help to develop better preventive inspections to detect bird crime incidents. We also recommended several management measures to help tackle bird crime more quickly and effectively.

Distribution, density and trends of the Eurasian eagle owl (Bubo bubo) population breeding in March-Thaya floodplain forests: impact of owlets on sustainability of natural nests

Fri, 18 Oct 2024 00:00:00 GMT

In this study, we investigated the Eurasian eagle owl (Bubo bubo) breeding in lowland forests in the trans-border area between western Slovakia, eastern Austria, and southern Moravia. The research provides new information on the reuse of nests by eagle owls and presents initial insights into population density and trends of eagle owls in the March-Thaya floodplains. Our 19-year monitoring has shown that the eagle owl has become a widespread breeder over the study area, with an increasing population trend. A total of 151 breeding attempts by eagle owls have been identified, occupying 82 natural nests (originally built by at least nine species of birds) and 12 artificial nests. With an average of 6.2 active nests per 100 km2 and a maximum of 17 active nests found in 2021 (~10.6 pairs per 100 km2), our findings represent one of the highest eagle owl breeding densities found, especially in comparison with core populations nesting in the mountains (the Carpathians, north-eastern Alps and the Bohemian Massif). Regarding the dynamics of nest reuse, our results reveal that only a third of nests used by eagle owls were reused by other raptors or storks (Ciconia sp.). Almost 50% of the natural nests in which eagle owl bred, subsequently disintegrated after the owlets had fledged. Lastly, black stork (Ciconia nigra) nests re-used by eagle owls were twice as likely to have disintegrated after the owlets had fledged than nests built by other bird species. Our results suggest that black stork nests in the March and Thaya floodplain forests are most susceptible to destruction.

Using birds of prey to manage pest bird flocks under lethal and non-lethal conditions – A review

Fri, 18 Oct 2024 00:00:00 GMT

Raptors have been successfully used to disperse and often control flocks of pest birds. However, the question that has not been resolved is, “If the raptor kills a small number of the target flock, does this improve the efficiency of control?” This mini-review examines the few research reports that have been published that can shed light on this question.

Two additional raptors to the Iraqi avifauna: The first observation of lappet-faced vulture (Torgos tracheliotos negevensis) and Amur falcon (Falco amurensis)

Fri, 18 Oct 2024 00:00:00 GMT

The Iraqi Organization for Conservation of Nature (IOCN) continuously conducts field surveys targeting key biodiversity areas within Iraq to discover the environmental conditions with more focus on the threatened species and their habitats. Two new bird species for Iraq were recorded during two of the ongoing field surveys conducted by IOCN, namely in the Khour Az-Zubair tidal mudflats in September 2022 and the Al-Najaf Desert in February 2023. Among the considerable list of the birds (and other fauna species) that have been observed, two bird species have been considered quite important: Amur falcon (Falco amurensis) and lappet-faced (or Arabian) vulture, Torgos tracheliotos negevensis]. Both of these observations have been carefully described and documented. Referring to the literature on the avifauna of Iraq, none of these bird species have already been considered Iraqi species and, subsequently, have been added to the list of avifauna of Iraq.

Raptor rehabilitation in Florida: Admission reasons, care duration, and release rates during the last fifteen years

Fri, 18 Oct 2024 00:00:00 GMT

Wildlife rehabilitators treat thousands of raptors yearly, providing an opportunity to better understand species’ biology, the changing environment, and the dangers raptors encounter in the wild. However, that data is siloed within individual facilities, making it challenging to understand the wider impact of rehabilitation and the dangers raptors face. Data were collected from 50 facilities across the state of Florida, United States of America, from 2009 to early 2023, representing 54,574 patients of 39 species. Patient intake at these facilities doubled between 2010 and 2020 over a relatively stable number of facilities (average = 31.5/year) with an average release rate of 36.6% (range 31.7 – 41.5%). Release rates varied significantly from 21% to 57% between species with over 100 recorded patients. Comparing release rates with the “cause for admission” provided a more nuanced understanding of what was affecting raptor patients and their release rates. Trauma was the most common cause of admission (40.2%) and has been relatively consistent year over year. For those patients with more specific identification attributes, 65% were male, 50% were adults, and patients spent an average of 16.6 days in care. The data provided in this study has the potential to make fundamental changes to raptor rehabilitation policies and encourage more collaboration between rehabilitators and researchers for the betterment of the patients in care.

Annual survival rates of satellite-tracked adult European honey buzzards (Pernis apivorus) based on the Kaplan-Meier estimator and its probabilistic extension

Wed, 26 Jun 2024 00:00:00 GMT

The annual survival rate of adult raptors is an important parameter in population dynamics and is needed to derive measures for population stability and conservation management. Here we studied adult European honey buzzards (Pernis apivorus), a migratory land bird, using satellite telemetry throughout the year for up to three years. We used the Kaplan-Meier method of survival estimation in combination with the distribution density function for survival. This function describes the number of survivors N as a function of time t, based on the survival rate SR. This probabilistic extension of the Kaplan-Meier estimator results in a simple method that does not require a commercial statistical program to extract survival rates from event time analysis. It can be applied to analysing any event-time data, not only telemetry results but also ring recoveries, as demonstrated using European honey buzzards as an example. The average adult survival rate in our study, based on permanent satellite telemetry monitoring, was 0.44/year (linear correlation factor f = 0.99). This implies an adult mortality rate of 0.56 per year. It seems that particularly unfavourable weather conditions during the crossing of the Sahara and the Mediterranean led to this high mortality rate of our birds during migration from 2001 to 2011, but is likely to vary greatly from year to year. However, the loss rate in the wintering area was also high, at one third of the birds. More honey buzzards need to be tracked throughout the year to assess factors affecting survival and threats to populations adequately.