Milvus Migrans Research Articles

The main factors and prospects for the restoration of biodiversity in technogenic territories (on the example of the Poltava Mining and Processing Plant)

Mining activities radically change natural ecosystems, the recovery of which is not possible without the restoration of native or transformed communities of autotrophic and heterotrophic organisms. In order to analyze the success of biodiversity restoration using unified methods, an inventory of higher plant flora and avifauna species in the technogenic territories of the Poltava Mining and Processing Plant was carried out. The dominant species identified in mining dumps, tailings, bypass and drainage canals, urban wastewater treatment and bioengineering facilities and on the PMP territory have been studied in detail. The studies were carried out in the spring-summer period of 2021–2022. The avifauna includes 140 species belonging to 18 orders and 45 families (Passeriformes predominate – 62.0%). 103 species nest on the PMP territory, 32 nomadic and 5 transient species are also registered. The nesting avifauna is dominated by representatives of both native nemoral (16.0%, n = 103) and forest-steppe (13.0%) and tropical (14.0%) avifauna. A significant number of birds belong to limnophiles, which prevail in the territories of the urban wastewater treatment plant (66.7%, n = 30) and tailings (62.5%, n = 24). They are also common in the bypass and drainage canals, where hydro- and hygrophilous phytocenoses have formed, similar to floodplain and real meadows as part of adjacent wetland ecosystems. Among the surrounding natural biogeocenoses, there are no steppe ones with their inherent unique floristic composition, which explains the small number of stepants in the studied flora and campophiles in the avifauna. In recovery successions, general patterns were revealed: biogeocenoses surrounding the technogenic territories of the PMP are the main source of producer diasporas and a variety of consumers, which are so necessary for the restoration of degraded landscapes. Phanerophytes from the genera Populus, Pinus, Fraxinus, Ulmus, Morus, Juglans, etc. are determinants in the sylvacenoses formed on the dumps and territories of the plant. Therefore, dendrophiles characteristic of neighbouring pine and floodplain forests, as well as garden phytocenoses in the private sector territory, dominate in the ornithocomplexes. Nationally rare avifauna includes 5 species, two of which nest. Among the identified bird species, the following nesting species are listed in the Red Book of Ukraine: Columba oenas, Himantopus himantopus, as well as transient and nomadic species: Hieraaetus pennatus, Haliaeetus allbicilla, Milvus migrans. The success of the natural formation of plant communities, the rich ornithological complex with the participation of rare species, and the location of the PMP territory within the migration routes indicate the expediency of further research into the possibilities of their inclusion in the nature reserve fund with the status of “territory of renaturalization”.

Habitats of House Sparrow Passer domesticus (Linnaeus, 1758) in Rameswaram Island, Tamil Nadu, India

This paper pertains to the nesting habitats of House Sparrow Passer domesticus with specific reference to population dynamics, nesting-related habits, nests, behaviours and other threats faced by these birds in Rameswaram Island. A total of 2,988 adult House Sparrows and 407 active nests were counted during the study. Of nests counted, 19% (n = 77) were solitary. The highest number of nests observed in a cluster was 9 (2 clusters). 60% of nests (n = 244) were found in concrete buildings, 39% (n = 159) in artificial nest-boxes, and 35% (n = 144) in cavities/crevices within buildings. House Sparrow population exhibited nesting plasticity, and 2% of nests were found constructed on vegetation. A wide variety of locally available materials, such as pieces of synthetic fishing nets, nylon ropes, and polythene papers were used for construction of nests. Sand and water bathing by birds were observed. Accidental fall of eggs and chicks, predation of nests by House Crows Corvus splendens, and unsuccessful attempts to predate adult birds by Black Kite Milvus migrans were observed, as well as opportunistic sightings of Shikra Accipiter badius.

Unequal clustering scheme for hotspot mitigation in IoT-enabled wireless sensor networks based on fire hawk optimization

Wireless sensor networks (WSNs) related to the Internet of Things (IoT) have shown incredible growth with technological advancements, offering a greater number of applications all over the world. Sensor nodes are deployed closer to the base station (BS) in some scenarios and held accountable for transmitting data from neighboring and own nodes against the BS and depletes energy. In the network, this problem is referred to as the "hotspot issue" and it may be fixed using procedures that use unequal clustering. In this study, a novel approach for IoT-assisted wireless sensor networks called the Fire Hawk Optimization-based Unequal Clustering Scheme for Hotspot Mitigation (FHOUCS-HSM) is developed. In the presented FHOUCS-HSM model, a first-order radio energy model has been utilized. The FHOUCS-HSM technique follows the foraging characteristics of whistling kites, black kites, and brown falcons. The design of the FHO algorithm for unequal clustering shows the novelty of the work. In addition to this, the FHOUCS-HSM model computes a fitness function for the use of uneven cluster size and the selection of cluster heads (CH). The comparative research highlights the advantages that the FHOUCS-HSM technique has over many models that are already in use.

Airborne microplastics detected in the lungs of wild birds in Japan

Microplastics (MPs) have been found in a wide range of animal species including humans. The detection of MPs in human lungs suggests that humans inhale airborne microplastics (AMPs). Although birds respire more efficiently than mammals and are therefore more susceptible to air pollution, little is known about their inhalation exposure to MPs. In this study, we analyzed samples isolated from the lungs of several species of wild birds in Japan by attenuated total reflection (ATR) imaging method of micro-Fourier transform infrared (μFTIR) spectroscopy to clear whether AMPs can be inhaled and accumulate within the lungs of wild birds. To isolate MPs from lung samples of rock doves (Columba livia), black kites (Milvus migrans), and barn swallows (Hirundo rustica) euthanized for pest control, digestion and density separation were performed. After each sample collected on an alumina filter was measured by ATR imaging method using μFTIR spectroscopy, the physical and chemical characteristics of the detected MPs were evaluated. Six MPs were detected in 3 of 22 lung samples. Polypropylene and polyethylene were found in rock doves and ethylene vinyl acetate was found in a barn swallow. Most MPs were fragments of 28.0–70.5 μm. Our results demonstrated that in addition to dietary sources, some wild birds are exposed to MPs by inhalation, and these MPs reach the lungs.

Миграция хищных птиц через Западный Кавказ в осенний период

Миграция хищных птиц через Западный Кавказ в осенний период

Генетическое родство популяций черного коршуна (Milvus migrans) юго-восточной Азии, Японии, Тайваня, Индии и Австралии: существует ли M. m. formosanus?

The range of the Black Kite (Milvus migrans) includes vast territories in Eurasia, Africa, and Australia. This raptor demonstrates unique ecological plasticity, inhabiting a variety of biotopes and readily taking the advantages of living close to humans. According to various sources, the Black Kite has from five to seven subspecies. Two of them inhabit in the Palearctic: the western part is occupied by the European Black Kite (M. m. migrans), and the eastern – by the Black-Eared Kite (M. m. lineatus). The islands of Japan are also inhabited by M. m. lineatus, however, this population is rather isolated from the mainland and may be genetically different. The routes of seasonal movements of these birds do not extend beyond the Japanese islands, while all the mainland kites of the eastern Palearctic make long-distance migrations from north to south and back. India and Indochina are inhabited by the Indo-Malayan subspecies (M. m. govinda), while Australia and adjacent islands are populated by (M. m. affinis). In addition, in the eastern part of mainland China, in Taiwan and Hainan, M. m. formosanus resembling the smaller form of M. m. lineatus was described at the beginning of the 20th century. Since then, this subspecies has been officially included in all taxonomic lists, but it has never been specifically studied. Since the first description of M. m. formosanus, the populations of the Black kite, like many other birds, have experienced a sharp decline in these areas due to intensive use of pesticides in agriculture. Currently, there is no data confirming the existence of M. m. formosanus as an independent genetic branch of the Black Kite. Previously, we found that Black Kite subspecies of Europe, North Asia, and India are genetically distinct and have their own haplogroups of the mitochondrial cytochrome B (CytB) gene. However, the low variability of the gene made it impossible to detect differences between the populations of India and Australia. Deciding to investigate the eastern subspecies in more detail, we analyzed the CytB and ND2 mitochondrial genes in the Black Kite populations of northeast Asia, India, Taiwan, Japan, and Australia. We found that Japanese kites carry only one of the two main haplogroups of Asian M. m. lineatus, indicating recent isolation from the mainland. The populations of India and Australia turned out to be very close genetically, but clearly separated by mitochondrial markers. Apparently, their common ancestor existed only about 100 thousand years ago, during the Last Glacial Period. Exploring nesting kites in Taiwan, we found both M. m. lineatus mitochondrial haplogroups, and a new haplogroup, which has never been found in other populations so far. Perhaps, in the recent past, an independent genetic branch of the Black Kite really lived on the island and it was quite isolated from the mainland. However, the recent decline in the local population, as well as the intensive expansion of M. m. lineatus led to the fact that the descendants of both subspecies currently inhabit Taiwan. In addition, a sharp decline in the number of kites in the 1970s apparently led to the formation of two genetically different populations in southern and northern Taiwan. The existence of such isolation with a relatively small distance between these populations is surprising and requires further research. The research is supported by the Russian Science Foundation (project no. 23-24-00185).

Evaluation of histo-toxicity of nimesulide in Black Kites (Milvus migrans): a pharmacodynamic study.

The present experimental work was conducted to elucidate the toxicity of nimesulide at three different doses in black kites (Milvus migrans). M. migrans is one of the most common raptors near human habitations. The goal of the current investigation was to determine whether nimesulide is similarly hazardous to raptors as was diclofenac sodium and to investigate the acute oral toxicity of nimesulide in these birds. For this study, eight adult male black kites (M. migrans) were randomly divided into four groups. M. migrans in the control group (n = 02) were not treated with nimesulide. The other three groups were given nimesulide doses. The birds in the first (n = 02) were declared the control group. The second (n = 02), third (n = 02), and fourth groups were administered nimesulide at a low, medium, and high dose of 2, 4, and 6 mg/kg live body weight of bird/day, respectively, for 10 days. Nimesulide-addled birds became listless and despondent, then anorexic. The birds were standing there with their eyes closed and showing no signs of life. There was an increase in saliva production, a slowing of breathing, and dilated pupils. No clinical signs were observed in the control group. No mortality was seen in the control or treated groups. The control group did not show lesions of gout, but black kites intoxicated with nimesulide at 2, 4, and 6 mg/kg live body weight of bird/day showed inflammation, apoptosis, hemorrhage, necrosis, and leukocytic infiltration tissues of the liver, kidney, and heart of black kites (M. migrans) treated with different concentrations of nimesulide. The treated groups also showed apoptosis of myofibrils and hyperplasia. The hypertrophy, atrophy, fibrosis, necrosis of skeletal muscles and hemorrhage were prominent in the muscles of black kites (M. migrans) intoxicated with nimesulide. All observed histological alterations got worse in a dose-related way. There was no significant difference in AST, ALT, ALP, serum uric acid, but a significant difference was observed in the values of serum urea (p = 0.001) and serum creatinine (p = 0.019).

Тринадцать лет наблюдений за миграцией хищных птиц в Батуми: наблюдения и их значение для охраны пернатых хищников России

One of the most important autumn migration bottlenecks for birds of prey in the Western Palearctic is situated in South-Western Georgia, between the east coast of the Black Sea and the range of Lesser Caucasus. Every year from mid-August till October at least 1% of the world’s population of 10 raptor species passes through this corridor. Specifically, over one million raptors are recorded annually, including on average 528467 Honey Buzzards (Pernis apivorus), on average 163985 Black Kites (Milvus migrans), 304819 Steppe Buzzards (Buteo buteo vulpinus), and around 8000 Lesser Spotted Eagles (Aquila [Clanga] pomarina). The specifics of the landscape and relief makes the foothills of the Lesser Caucasus to the north of Batumi an ideal spot for counting raptor migration, and since 2008, an international team of volunteers, the Batumi Raptor Count, has monitored autumn raptor migration from two strategic vantage points. The count effort is focused on 7 priority species, including Honey Buzzard, Black Kite, Lesser Spotted Eagle, Booted Eagle (Hieraaetus pennatus), Marsh, Montagu’s and Pallid Harriers (Circus aeruginosus, C. pygargus, C. macrourus, respectively). In addition, 13 other diurnal raptor species and 10 non-raptor bird species are monitored at the BRC. Using the trektellen-app, BRC is able to record all data digitally in the field, and to provide daily updates of migration counts on its website. At the end of each season, the data is cleaned and made available through the Global Biodiversity Information Facility (GBIF). Protocols were developed to standardize count effort across years, thus allowing an accurate assessment of population trends in the priority species. Importantly, the BRC systematically records data on the age and sex of raptors, allowing to infer trends separately for different demographic groups. The standardized data collected from 2011 till 2019 revealed rather stable numbers for most priority species, but also a significant annual decrease in numbers of juvenile Montagu’s Harriers; a strong ongoing increase in numbers of both juvenile and adult Black Kites; and increase in numbers of adult Booted Eagles accompanied by a decrease in juvenile birds of this species. Based on GPS-tracking studies on a variety of species, it appears that the western border of the breeding area for the populations counted by BRC is most probably not too far away from the western border of Russia. At least in case of Spotted Eagles, individuals breeding in the Baltic States, Finland, and Germany tend to use the migration routes to the West from the Black Sea, and this is also the case for birds from Western Ukraine and Belarus. There is insufficient data available to define the eastern border for the populations migrating through Batumi. We do know that raptors tracked from the south of Siberia tend to migrate to the east from the Caspian Sea, although some Pallid Harriers tracked from Russia and Kazakhstan do migrate over the Caucasus. All considered, we assume that the vast majority of raptors observed in Batumi during autumn migration breed in Central European Russia up to the Ural Mountains. A comparison of Batumi counts with the breeding population size estimates in Russia and neighbouring countries suggests that a significant proportion of the Russian population of the Lesser Spotted Eagle and Honey Buzzard is passing through the Batumi bottleneck on migration. Trends in migration counts at Batumi are probably representative of changes in raptor breeding populations from European Russia and Western Kazakhstan. In addition to collecting the data on migration, the BRC supports the development of ecotourism in the area and combats the widespread poaching of migrating raptors in Georgia by implementing various educational programs in schools and higher education institutions in Georgia. The BRC would like to build stronger links with professional ornithologists and amateur birdwatchers from the breeding areas of the raptors that pass through Batumi each year, and cordially invites everyone to participate in its migration counts.

Forest raptor nest selection traits in Mediterranean forest (Maamora, North Africa): conservation implications

SummaryForest raptor nest-site selection is mostly influenced by the quality of the habitat, food resources, and competition. Here, we identified common targets of trees selected as breeding sites and differences in selection traits, i.e. prey availability and intra- and interspecific competition, among Booted Eagle, Long-legged Buzzard, Black Kite, and Common Kestrel in a Mediterranean Cork Oak forest (private protected reserve of 25 km2). Using generalised linear mixed models we developed species-specific models describing nesting habitat selection. We tested the overlap in nesting habitat selection among species using environmental principal component analysis. The densities of forest raptor breeding pairs were high (3.1 pairs/km2) and the distance between occupied territories was short, strongly connected with food availability and competition. The results showed that all the species, with the exception of Common Kestrel, selected for nesting areas characterised by higher conspecific distance, highlighting the importance of conspecific competition. Booted Eagle and Black Kite selected areas with a high abundance of rabbits. The height of the nesting tree, the size and distance between surrounding trees, and the scrub cover were significant habitat characteristics for Booted Eagle and Long-legged Buzzard. Indeed, the environmental analyses showed a moderate nest site overlap between Black Kite and both Booted Eagle and Long-legged Buzzard, and a high overlap between Common Kestrel and both Booted Eagle and Long-legged Buzzard. Our study improves knowledge of the habitat requirements for nest selection and the potential competitive interactions between these raptor species in Mediterranean forests, and highlights the need for implementation of habitat management and conservation strategies.

Современный статус балобана в России и в Казахстане

Современный статус балобана в России и в Казахстане

Study of Breeding and Migrations of the Golden Eagle in Mongolia

Golden Eagles (Aquila chrysaetos) play a crucial role in the ecosystems of the Bayan-Ulgii province and its neighboring regions. Our research focuses on the comprehensive survey of Golden Eagle nests and study of their migration patterns via the satellite tracking, providing valuable insights into population dynamics and migratory behaviors. In the years 2021 and 2022, we accomplished an extensive search for Golden Eagle eyries across 13 diverse counties in Bayan-Ulgii province, including Altai, Altantsugts, Bayannuur, Bayan-Ulgii, Bugat, Deluun, Erdeneburen, Nogoonnuur, Sagsai, Tolbo, Tsagaannuur, Tsengel, and Ulaankhus. This collaborative effort in partnership with local communities and herders allowed us to identify and document a total of 75 Golden Eagle nests, with 49 being active during this two-year period. To deepen our understanding of these majestic birds, a satellite tracking program was started in September 2019 during the Ulaankhus Eagle Festival. Through GPS tagging, we monitored the migration of five Golden Eagles, previously used in Kazakh falconry and subsequently released. This tracking initiative provided us with valuable data on their movements and behaviors, shedding light on their survival challenges and migration routes. Our research not only contributes to the conservation efforts of Golden Eagles but also enhances our understanding of the interconnectedness of various raptor species within the region, including Bearded Vultures (Gypaetus barbatus), Cinereous Vultures (Aegypius monachus), Black Kites (Milvus migrans), Steppe Eagles (Aquila nipalensis), Peregrine Falcons (Falco peregrinus), and Saker Falcons (Falco cherrug). The study of these species in their natural habitats enriches our understanding of the intricate ecological dynamics at play. By sharing our findings, we aim to foster a deeper appreciation for these iconic birds and promote their conservation in the Bayan-Ulgii province and beyond. Our presentation will highlight the results of our Golden Eagle nest survey and tracking, emphasizing the importance of community involvement in wildlife research and conservation.

Тайваньский чёрный коршун: существует ли подвид formosanus?

In 1920, a distinct Black Kite subspecies, Milvus migrans formosanus, was described on the island of Taiwan and since then it is officially recognized by all major taxonomic lists. However, there are no morphological or genetic studies that would confirm the existence of the Taiwanese kite as a separate, isolated population distinct from the mainland one. We compared 27 specimens from Taiwanese population with all the main Black Kite subspecies of Eurasia and Australia based on a mitochondrial cytochrome B gene fragment. It turned out that representatives of all the main haplogroups common in the mainland M. m. lineatus population currently live in Taiwan, however, 30% of the island population carries a special haplogroup that has not been found on the mainland. Thus, there is no reason to believe that an isolated population of a special subspecies M. m. formosanus may currently live in Taiwan. It is possible that such a population actually existed in the first half of the 20th century, but due to a catastrophic decline due to pesticide poisoning, as well as due to repeated hybridization with newcomers from the mainland population, the Black Kite of Taiwan is a mixed population that has little in common with M. m. formosanus, described more than 100 years ago.

CMS Raptors MOU: New Opportunities for Raptors Conservation in Africa and Eurasia Emerging from the Third Meeting of Signatories

The Convention on Migratory Species’ Memorandum of Understanding on the Conservation of Migratory Birds of Prey in Africa and Eurasia (Raptors MOU) represents a unique international agreement dedicated to the preservation of migratory raptors belonging to the orders Accipitriformes, Falconiformes, and Strigiformes. At the Third Meeting of Signatories to the Raptors MOU (MOS3), held in Dubai from 3 to 6 July 2023, significant progress was made towards advancing commitments for the conservation of these majestic birds. The primary outcomes of MOS3 are summarized below. Revised MOU mandate: An evaluation of the MOU’s implementation conducted in 2020 underscored the need to better align and enhance the clarity of the commitments contained in the MOU’s Text and in its Annexes (one of which being the MOU’s Action Plan). Consequently, several amendments to these documents were made. Notably, the Activities of the MOU’s Action Plan were comprehensively rewritten, with each now being accompanied by clear targets and means of verification. Updated list of species: The MOU now encompasses 94 distinct species of migratory bird of prey. Notably, the Yellow-billed Kite (Milvus aegyptius) is now recognized as a separate entity from the Black Kite (M. migrans). In addition, the MOU’s revision includes the new order Accipitriformes. Revised species categorization: Species listed under the Raptors MOU are categorized into one of three categories based on their extinction risk. At MOS3, individual species’ categories were updated according to the latest IUCN Red List assessment. The update resulted in an increased number of species classified under Category 1 (globally threatened or Near Threatened species) and Category 2 (species considered to have an unfavourable conservation status at a regional level), reflecting a deteriorating conservation status for 13 species. Conversely, only three species saw their conservation status improve and move to a lower category. Expanded list of internationally important sites for raptors: The MOU previously included a “Provisional list of Important Bird Areas that are known to be significant congregatory sites for birds of prey in Africa and Eurasia”. Now named “List of Internationally Important Sites for Migratory Birds of Prey”, the list has been broadened to incorporate sites listed as Important Bird Areas due to their importance for at least one species listed in Annex 1 of the MOU or because are “bottleneck” locations for migrating raptors. Additionally, those sites proposed by Signatories as meeting the same criteria have been included. Furthermore, for States current and former Members of the European Union the list includes sites designated as Special Protection Areas under the European Council’s Birds Directive. This network of important sites now represents the most extensive collective effort for raptor conservation in Africa and Eurasia, with the potential to significantly contribute to their preservation. Renewed membership of the Technical Advisory Group to the Raptors MOU (TAG): The purpose of the TAG is to serve and assist Signatories in the effective implementation of the Raptors MOU. A renewed TAG membership was elected at MOS3, increasing the number of serving women from one to four. First Raptor Conservation Status Assessment Report: Under the coordination of BirdLife International, the TAG has produced an assessment report of the conservation status of the raptor species covered by the MOU. This report paints a disconcerting picture of the rapidly declining conservation status of the 94 listed species, with 54% presenting declining global populations and 34% now facing elevated extinction risk. The most threatened group are Vultures (93% of spp. included in Category 1), followed by Eagles (50%) and Falcons (26%). The rate of extinction of migratory raptor listed in the MOU is outpacing that of all birds and even all raptors in general. The report emphasizes that the principal threats to these birds are habitat loss and degradation, illegal killing and taking, and electrocution and collision with energy infrastructure. Notably, the impact of electrocution and collision may be underestimated, as one-third of satellite-tagged raptors (excluding vultures) fall victim to these hazards. In light of these alarming findings, it is evident that a coordinated, collaborative effort involving researchers, conservationists, governments and other stakeholdersis imperative to mitigate the decline of migratory raptors. The Raptors MOU stands as a crucial technical framework that can facilitate and guide these essential conservation endeavors. The development of International Single Species Action Plans for Black Harrier (Circus maurus), Steppe Eagle (Aquila nipalensis), Beaudouin’s Snake Eagle (Circaetus beaudouini), Pallas’s Fish Eagle (Haliaeetus leucoryphus), Steller’s Sea Eagle (H. pelagicus) and Tawny Eagle (A. rapax) is considered a priority.

Status of raptors in turahalli minor forest, Bangalore, Karnataka, India

Present study was conducted at Turahalli minor forest, Bangalore to understand the status of raptors in forest habitats. Observational investigations of avian studies were carried out using field binoculars and DSLR camera and line transect method was adopted for bird counting. Total fifteen species of raptors belonging to Falconidae, Accipitridae and Strigidae families were recorded during study period i.e. 'March 2019 to Dec 2021'. Black kite and Brahminy kite have highest population and most dominant species in the study site, whereas common kestrel, Besra, Changeable hawk eagle was rarely observed. Field study was conducted in three different seasons summer, winter and rainy. Maximum number of individuals were recorded during summer (171) followed by winter (141) and rainy (50) season respectively. Data were analyzed using Shannon-wiener diversity Index, species diversity (H=1.875), species richness (SR=2.376) and evenness (E=0.4336). In winter species diversity was more (1.976) followed by summer (1.741) and rainy (1.523) season. In terms of distribution status of raptors 79% were resident, 14% winter visitor, 7% partial visitors.

Black kites wintering in Europe: estimated number, subspecies status, and behaviour of a bird wintering on Crete and Turkey

Black kites of the nominal subspecies Milvus migrans migrans breed in Europe and winter regularly in sub-Saharan Africa and the Middle East. As a new phenomenon, black kites with morphological characteristics of the subspecies Milvus migrans lineatus are observed in Europe. Based on observations of black kites in winter 2020/2021 summarized in this paper, based on other recent reports about wintering black kites in Europe and based on juvenile black kite tagged on Crete and tracked for two years, we conclude that hundreds to thousands of black kites are now regularly wintering in south of Europe, and in smaller numbers in other parts of Europe as well as in northern Africa. The growing number of wintering black kites in Europe is apparently caused by members of the population from a hybrid zone between M. m. migrans and M. m. lineatus breeding east of the Urals, i.e. from the area of the European part of Russia. This is consistent with the hypothesis of the spreading of M. m. lineatus and a subsequent hybridization zone between M. m. migrans and M. m. lineatus in a westerly direction from Siberia across continental Europe. Moreover, two black kites found dead on Crete were attributed to M. m. lineatus and M. m. migrans by cytochrome B gene sequence analyses. The juvenile black kite with lineatus features tagged on Crete and telemetrically tracked during the next two years moved to the south-western part of Russia during the next two summers, but did not breed. It spent the following two winters at the same landfill in south-western Turkey. It seems that an adaptation to food sources provided by municipal waste landfills is important for black kites wintering in Europe, the Middle East and Morocco. Highlights • Hundreds to thousands of black kites are now regularly wintering in Europe. • The growing number of wintering black kites is caused by birds from a hybrid zone between Milvus migrans migrans and M. m. lineatus in eastern Europe. • Municipal waste landfills are important as food sources for black kites wintering in Europe.

Second-generation anticoagulant rodenticides in the blood of obligate and facultative European avian scavengers

The widespread use of second-generation anticoagulant rodenticides (SGARs) and their high persistence in animal tissues has led to these compounds becoming ubiquitous in rodent-predator-scavenger food webs. Exposure to SGARs has usually been investigated in wildlife species found dead, and despite growing evidence of the potential risk of secondary poisoning of predators and scavengers, the current worldwide exposure of free-living scavenging birds to SGARs remains scarcely investigated. We present the first active monitoring of blood SGAR concentrations and prevalence in the four European obligate (i.e., vultures) and facultative (red and black kites) avian scavengers in NE Spain. We analysed 261 free-living birds and detected SGARs in 39.1% (n = 102) of individuals. Both SGAR prevalence and concentrations (ΣSGARs) were related to the age and foraging behaviour of the species studied. Black kites showed the highest prevalence (100%), followed by red kites (66.7%), Egyptian (64.2%), bearded (20.9%), griffon (16.9%) and cinereous (6.3%) vultures. Overall, both the prevalence and average ΣSGARs were higher in non-nestlings than nestlings, and in species such as kites and Egyptian vultures foraging in anthropic landscapes (e.g., landfill sites and livestock farms) and exploiting small/medium-sized carrions. Brodifacoum was most prevalent (28.8%), followed by difenacoum (16.1%), flocoumafen (12.3%) and bromadiolone (7.3%). In SGAR-positive birds, the ΣSGAR (mean ± SE) was 7.52 ± 0.95 ng mL−1; the highest level detected being 53.50 ng mL−1. The most abundant diastereomer forms were trans-bromadiolone and flocoumafen, and cis-brodifacoum and difenacoum, showing that lower impact formulations could reduce secondary exposures of non-target species. Our findings suggest that SGARs can bioaccumulate in scavenging birds, showing the potential risk to avian scavenging guilds in Europe and elsewhere. We highlight the need for further studies on the potential adverse effects associated with concentrations of SGARSs in the blood to better interpret active monitoring studies of free-living birds.

Nicotinamide adenine dinucleotide reduced (NADH) is a natural UV filter of certain bird lens

In this work, we for the first time report the identification of UV filters in the bird eye lens. We found that lenses of some raptors (black kite, common buzzard) and waterfowl (birds from Podicipedidae family) contain unusually high levels of reduced nicotinamide adenine dinucleotide (NADH)—a compound with high absorption in the UV-A range with a maximum at 340 nm. The lens metabolome of these birds also features an extremely low [NAD +]/[NADH] ratio. Chemometric analysis demonstrates that the differences between the metabolomic compositions of lenses with low and high NADH abundances should be attributed to the taxonomic features of bird species rather to the influence of the low [NAD +]/[NADH] ratio. We attributed this observation to the low metabolic activity in lens fiber cells, which make up the bulk of the lens tissue. Photochemical measurements show that properties of NADH as a UV filter are as good as that of UV filters in the human lens, including strong absorption in the UV-A spectral region, high photostability under both aerobic and anaerobic conditions, low yields of triplet state, fluorescence, and radicals under irradiation. Lenticular UV filters protect the retina and the lens from photo-induced damages and improve the visual acuity by reducing chromatic aberrations; therefore, the results obtained contribute to our understanding of the extremely high acuity of the raptor vision.

Raptors at risk: Attributes of mortality within an anthropogenic landscape in the Mid-Hills region of Nepal

Wildlife rescue and rehabilitation centers offer important insights regarding the threats and attributes associated with raptor casualties. We utilized a data set on raptors admitted to a single wildlife rescue center (WRC) in the Mid-Hills region of Nepal by applying two approaches. First, we explored the overview of species admitted and the cause of admission at WRC, and modeled the outcome (survival, mortality) of frequently admitted raptor species (FARS) by analyzing the cause of admittance, the season of admittance, and age category through binary logistic regression. Second, we identified the high-risk zone for raptors through an ensemble approach using multiple species distribution modeling algorithms in BIOMOD2. A total of 17 species of raptors with 830 cases of admittance; Black Kite (Milvus migrans) 47%, Barn Owl (Tyto alba) 24%, Eurasian Eagle-Owl (Bubo bubo) 12%, and other species (17%) were recorded at the WRC over the course of five years (2017–2021). Unknown causes (39%) comprised the largest proportion of admittance, followed by illegal captivity (17%), injured by dogs (10%), and injured by humans (10%). Among the three FARS, the mortality rate was highest in the Barn Owl (62%), followed by the Eurasian Eagle-Owl (55%) and the Black Kite (47%). The model with an additive effect of species, cause, and age category was the best fit model to predict the outcome for FARS. Out of the total study area (705 km2), 19% was under high-risk, 41% was under medium-risk, and 40% was under low-risk. Most of the high-risk zones were incorporated within agricultural areas (57%) and built-up areas (31%). The variation in mortality rate among the FARS indicates that species-specific conservation strategies need to be developed to reduce casualty risk. Identified potential anthropogenic threats and their impact on the survivability and mortality of raptors in this study could help to mitigate casualties. Moreover, the high-risk areas associated with raptor casualties in this study need to be prioritized to implement the conservation endeavors for the raptors.

Sustaining Increasing Wintering Raptor Populations in Central Israel: A 38 Years Perspective

Censusing wintering raptors has proved useful in detecting changes in populations. Israel is a well-known bottleneck for soaring birds in the autumn and the spring. Despite the many studies on migratory raptors in Israel, none have undertaken the study of the overwintering raptors consistently over extended periods, such as 1985–2022, a period of 38 years. During the study, conducted in central Israel, we recorded 44,120 individuals from 32 species. The most frequently observed species were Black Kite (Milvus migrans; 59.1%), Common Kestrel (Falco tinnunculus; 18.1%), and Steppe Buzzard (Buteo vulpinus; 6.6%). We found an increase in the total number of individuals, where the mean increase compared to the starting year was 851.6 ± 1071.2%, and the average annual growth was 43.7 ± 158.8%, respectively. A similar pattern was found in the number of species during the study period, where the mean annual increase was 17.1 ± 20.5%, and the average annual growth rate of species richness was 2.2 ± 16.2%. However, an evaluation of the mortality from power lines of two listed species suggests that the wintering raptors are not well protected in the study area. The conservation of these raptors and the possible sustainability of their wintering populations into the future, some of which are on the IUCN Red List, are of great importance, and the authorities should try and understand the human demographics and mesohabitat changes that appear to influence the wintering capabilities of the raptor populations.

Fungal signatures of oral disease reflect environmental degradation in a facultative avian scavenger.

Degradation of natural ecosystems increases the risk of infections in wildlife due to microbiota dysbiosis. However, little is known about its influence on the development of fungal communities in predators and facultative avian scavengers. We evaluated the incidence of oral disease in wild nestling black kites (Milvus migrans) under contrasting environmental degradation conditions, and explored their oral fungal patterns using molecular methods and multivariate analysis. Oral lesions were found in 36.8% of the 38 nestlings examined in an anthropogenically altered habitat (southeastern Madrid, Spain), but in none of the 105 nestlings examined in a well-conserved natural area (Doñana National Park, Spain). In a subsample of 48 black kites, the composition of the oral fungal community differed among symptomatic nestlings from Madrid (SM) and asymptomatic nestlings from Madrid (AM) and Doñana (AD). Opportunistic fungal pathogens (e.g., Fusarium incarnatum-equiseti species complex, Mucor spp., Rhizopus oryzae) were more prevalent in SM and AM than in AD. Hierarchical clustering and principal component analyses revealed that fungal patterns were distinct between both study areas, and that anthropogenic and natural environmental factors had a greater impact on them than oral disease. Fungal signatures associated with anthropogenic and natural stresses harbored some taxa that could be used to flag oral infection (F. incarnatum-equiseti species complex and Alternaria), indicate environmental degradation (Alternaria) or provide protective benefits in degraded environments (Trichoderma, Epicoccum nigrum and Sordaria). Co-occurrence associations between potentially beneficial and pathogenic fungi were typical of AM and AD, hinting at a possible role in host health. This study shows that early-life exposure to highly degraded environments induces a shift towards a higher prevalence of pathogenic species in the oral cavity of black kites, favoring oral disease. Furthermore, our findings suggest potential ecological applications of the monitoring of oral mycobiome as a bioindication of oral disease and environmental degradation.