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Radar is a powerful technology for surveys of avian movements. Validating the accuracy of radar detection is essential when establishing quantitative criteria for tracking bird trajectories and counting bird flocks. This study clarifies the positional and biological factors influencing the probability of detection (POD) and echo size on X-band marine radar. The bird trajectory for validation was obtained by ornithodolite at the same time as the radar scan. Distance was found to have a negative effect on POD and echo size, while elevation angle positively affected POD. Body mass and flock size positively affected POD and echo size. In predicting detection performance, the survey distance required to achieve 50% POD was 750 m or less for Grey-faced Buzzard, the lightest target species, but up to 1800 m for a pair of Bewick's Swan. Our study provides survey and analysis procedures that allow for efficient validation using ornithodolites. Then, we identify the range settings that should be considered for target species and contribute to establishing criteria for quantitative radar bird surveys. [ABSTRACT FROM AUTHOR]

South‐central Alaska features a history of massive volcanic activity. How the Denali volcanic gap (DVG) formed and why the Wrangell volcanoes are clustered remain vigorously debated. Investigating the crustal thermal structure can be crucial for understanding subsurface magmatic activity. We present a high‐resolution broadband Lg‐wave attenuation model to constrain crustal thermal anomalies beneath Alaska. Strong Lg attenuation is observed beneath the volcanoes in south‐central Alaska, indicating thermal anomalies and possible melting in the crust. In contrast, the central Yakutat terrane (YT) and DVG are characterized by weak Lg attenuation, suggesting the existence of a cool crust that prevents hot mantle materials from invading the crust. This cool crust is likely the reason for the DVG. Quarter‐toroidal crustal melting with strong attenuation is revealed around the YT. This curved zone of crustal melting, possibly driven by toroidal mantle flow, weakly connects the Wrangell and Buzzard Creek‐Jumbo Dome magmatic chambers. Plain Language Summary: The Alaskan mainland is located at the western end of the North American plate. This region is adjacent to the Bering Sea to the west and overlies the subducting Pacific Plate to the south. The Yakutat microplate subducts northward below Alaska with a velocity similar to that of the Pacific plate but with a lower angle. Many volcanoes have developed in south‐central Alaska, including those in the Aleutian arc, the Buzzard Creek‐Jumbo Dome, and the Wrangell volcanic field (WVF). However, the origins, storage and transport patterns of the magmas feeding these volcanoes are still unclear and under debate. In this study, we conduct Lg‐wave attenuation tomography on the Alaskan mainland and use the results to investigate the regional crustal thermal structure. The imaging results reveal a cold Yakutat terrane and hot crustal features beneath the volcanoes. The Denali volcanic gap is characterized by weak crustal attenuation, indicating that cool crust may have inhibited volcanic activity. Quarter‐toroidal crustal melting is revealed by a curved belt of strong attenuation. The crustal magmatic chambers may weakly connect the WVF and the Buzzard Creek‐Jumbo Dome volcanoes. Key Points: A high‐resolution broadband Lg‐wave attenuation model is obtained for the Alaskan mainlandStrong Lg‐wave attenuation beneath the volcanoes indicates crustal thermal anomalies and meltingA quarter‐toroidal crustal melting belt weakly connects the magmatic chambers beneath the Buzzard Creek‐Jumbo Dome and Wrangell volcanoes [ABSTRACT FROM AUTHOR]

The avian scavenger raptors guild of Patagonia, the southernmost region of South America (37–56°S), comprises 3 species of obligate scavengers and 7 species of facultative scavengers. Despite the species richness, there is little information about the anthropogenic threats this guild might face. Here, based on 164 h of observations and photographic records across 3 austral winters, we reveal a broad range of lesions (missing legs, digits or talons, fractures, luxations, pododermatitis, necrosis, hyperkeratosis, and beak and ocular lesions) and mortalities among scavenger raptors in Argentine Patagonia at 2 anthropogenic food-rich sites located 1,750 km apart at 38° and 54°S. We photographed 146 individuals with 174 physical lesions and found 61 dead individuals, including one obligate scavenger species (Black Vulture, Coragyps atratus) and 4 facultative scavenger species (Crested Caracara, Caracara plancus; Chimango Caracara, Daptrius chimango; White-throated Caracara, D. albogularis; and Black-chested Buzzard-Eagle, Geranoaetus melanoleucus). Ninety percent of the lesions we recorded on the individuals were located on their hindlimbs. None of the carcasses we found exhibited any apparent lesions. The precise nature and origins of these lesions and mortalities remain uncertain. However, the hindlimb lesions align with the effects of leg-hold traps, while poisoning emerges as the most likely cause of mortality among individuals foraging at these anthropogenic food-rich sites. These findings suggest a notable human-induced threat to the avian scavenger raptors guild in Patagonia. [ABSTRACT FROM AUTHOR]

Biotic homogenization is a process whereby species assemblages become more similar through time. The standard way of identifying the process of biotic homogenization is to look for decreases in spatial beta–diversity. However, using a single assemblage‐level metric to assess homogenization can mask important changes in the occupancy patterns of individual species. Here, we analysed changes in the spatial beta–diversity patterns (i.e. biotic heterogenization or homogenization) of British bird assemblages within 30 km × 30 km regions between two periods (1988–1991 and 2008–2011). We partitioned the change in spatial beta–diversity into extirpation and colonization‐resultant change (i.e. change in spatial beta–diversity within each region resulting from both extirpation and colonization). We used measures of abiotic change in combination with Bayesian modelling to disentangle the drivers of biotic heterogenization and homogenization. We detected both heterogenization and homogenization across the two time periods and three measures of diversity (taxonomic, phylogenetic, and functional). In addition, both extirpation and colonization contributed to the observed changes, with heterogenization mainly driven by extirpation and homogenization by colonization. These assemblage‐level changes were primarily due to shifting occupancy patterns of generalist species. Compared to habitat generalists, habitat specialists had significantly (i) higher average contributions to colonization‐resultant change (indicating heterogenization within a region due to colonization) and (ii) lower average contributions to extirpation‐resultant change (indicating homogenization from extirpation). Generalists showed the opposite pattern. Increased extirpation‐resultant homogenization within regions was associated with increased urban land cover and decreased habitat diversity, precipitation, and temperature. Changes in extirpation‐resultant heterogenization and colonization‐resultant heterogenization were associated with differences in elevation between regions and changes in temperature and land cover. Many of the ‘winners’ (i.e. species that increased in occupancy) were species that had benefitted from conservation action (e.g. buzzard (Buteo buteo)). The ‘losers’ (i.e. those that decreased in occupancy) consisted primarily of previously common species, such as cuckoo (Cuculus canorus). Our results show that focusing purely on changes in spatial beta–diversity over time may obscure important information about how changes in the occupancy patterns of individual species contribute to homogenization and heterogenization. [ABSTRACT FROM AUTHOR]

The article focuses on the excitement of Dolphin and his band, The Buzzards, as they embark on a successful tour with merchandise designed by Dolphin's girlfriend, Cindy. Topics include the band's growing fan base, Cindy's pivotal role in managing merchandise sales, and the camaraderie and thrill of touring as they perform in various cities across the Midwest.

We work out the exact relationship between algebraic modular forms for a two-by-two general unitary group over a definite quaternion algebra, and those arising from genera of positive-definite quinary lattices, relating stabilisers of local lattices with specific open compact subgroups, paramodular at split places, and with Atkin-Lehner operators. Combining this with the recent work of Rösner and Weissauer, proving conjectures of Ibukiyama on Jacquet-Langlands type correspondences (mildly generalised here), provides an effective tool for computing Hecke eigenvalues for Siegel modular forms of degree two and paramodular level. It also enables us to prove examples of congruences of Hecke eigenvalues connecting Siegel modular forms of degrees two and one. These include some of a type conjectured by Harder at level one, supported by computations of Fretwell at higher levels, and a subtly different congruence discovered experimentally by Buzzard and Golyshev. [ABSTRACT FROM AUTHOR]

During spring migration, in several species of birds males tend to reach earlier than females the breeding grounds to occupy the best territories. Because of this competition, in some species males tend to migrate on shorter distances than females to cover shorter flyways in spring. A previous study made in the wintering grounds suggested that this could be the case of the European Honey Buzzard (Pernis apivorus), a migrant raptor breeding in Western Palearctic and wintering south of the Sahara desert. To verify if a differential timing of spring migration between sex classes occurs in this species, a 5-year study was carried out at the Strait of Messina, a bottleneck located along the Central Mediterranean flyway, between 8 April and 31 May 2019–2023. The results showed that, as predicted, the passage of adult males occurs a few days earlier. In particular the median dates of the passage occurred May 2nd and May 8th, for males and females respectively. [ABSTRACT FROM AUTHOR]

Competition within and between species affects community structure and is well documented in raptors. We investigated the spatial distribution of two sympatric raptors in Cyprus, the Bonelli's Eagle (BE) and the Long-legged Buzzard (LLB). Both species are facultative tree/cliff nesters, with overlapping nesting and foraging areas. In 2021, the BE population consisted of 40 pairs with a density of 1,3 pairs/100 km2, and the LLB population of 113 pairs with 2,9 pairs/100 km2. About 80% of BE nesting sites and 43% of LLB nesting sites were situated within the Natura 2000 (N2K) protected areas network while 97% of BE nesting sites and 91% of LLB's were situated within 2.5 km from N2K areas. The spatial distribution was compared between and within species based on Nearest Neighbour Distance (NND) analysis. Average intraspecific NND for BE was 6.158 ± 2.207 m (SD), almost double compared to LLB which was 3.151 ± 1.730 m (SD). The distribution of BE nesting territories showed a regular spacing, indicating a stronger effect of intraspecific competitive interactions, whereas LLB nesting territories did not differ significantly from random. Average interspecific NND for BE was 5.339 ± 3.719 m (SD) and for LLB 5.673 ± 3.931 m (SD). Only the LLB had a regular pattern, suggesting that LLB pairs take into account neighbouring BE active territories when establishing their own, while the opposite is not the case. Therefore, the LLB, which is the smaller of the two raptors, avoids BE nesting sites by placing its nests further than to conspecifics. NNDs in 2021 were lower compared to previous studies in Cyprus, in 2005 for LLB and 2009 for BE, indicating an increase in both species' densities. [ABSTRACT FROM AUTHOR]

Background: Exploring the dynamics of gut microbiome colonisation during early-life stages is important for understanding the potential impact of microbes on host development and fitness. Evidence from model organisms suggests a crucial early-life phase when shifts in gut microbiota can lead to immune dysregulation and reduced host condition. However, our understanding of gut microbiota colonisation in long-lived vertebrates, especially during early development, remains limited. We therefore used a wild population of common buzzard nestlings (Buteo buteo) to investigate connections between the early-life gut microbiota colonisation, environmental and host factors. Results: We targeted both bacterial and eukaryotic microbiota using the 16S and 28S rRNA genes. We sampled the individuals during early developmental stages in a longitudinal design. Our data revealed that age significantly affected microbial diversity and composition. Nest environment was a notable predictor of microbiota composition, with particularly eukaryotic communities differing between habitats occupied by the hosts. Nestling condition and infection with the blood parasite Leucocytozoon predicted microbial community composition. Conclusion: Our findings emphasise the importance of studying microbiome dynamics to capture changes occurring during ontogeny. They highlight the role of microbial communities in reflecting host health and the importance of the nest environment for the developing nestling microbiome. Overall, this study contributes to understanding the complex interplay between microbial communities, host factors, and environmental variables, and sheds light on the ecological processes governing gut microbial colonisation during early-life stages. [ABSTRACT FROM AUTHOR]

Simple Summary: The measurement of stress in wildlife, especially using non-invasive methods, is an important tool when monitoring wild animals taken into human care. However, the methods used to measure stress hormone metabolites from feces must be validated for each species. Eight Common Buzzards habituated to humans were placed into prepared aviaries and their feces were collected over a period of seven days. For biological validation, handling and restraint were used as a stress event. Hormone metabolites were analyzed using three different enzyme immunoassays to find the most suitable one. In addition, a degradation experiment was conducted to find out how long the fecal glucocorticoid metabolites (fGCMs) remained stable in the feces at room temperature. The cortisone enzyme immunoassay detected a distinctive peak of excreted glucocorticoid metabolites in response to the stress event. We found no significant differences between the sexes, but a diurnal variation in the stress hormone metabolites. Immunoreactive metabolite concentrations showed a significant change eight hours after defecation, indicating degradation processes. Our study successfully validated the non-invasive measurement of fGCMs as a stress indicator in the Common Buzzard and could lay the foundation for future studies providing new insights for animal welfare research in this species. For wild animals, being in captivity in wildlife centers can cause considerable stress. Therefore, it is necessary to establish and validate non-invasive tools to measure chronic stress during rehabilitation. Eight Common Buzzards which lived in permanent husbandry were placed individually into prepared aviaries and their feces were collected before, during and after a stress event for biological validation over a period of seven days. The extracted fecal glucocorticoid metabolites (fGCMs) were analyzed with three different enzyme immune assays (EIA) to find the most suitable one. Additionally, we aimed to investigate the stability of fGCM levels after defecation because further metabolization by bacterial enzymes can lead to changed results. The Cortisone-EIA performed best in males and females and showed that the stress event led to an fGCM increase of 629% (557% in females and 702% in males) in relation to basal values. We found no significant differences between the sexes, but observed significant differences between different times of day. FGCM concentration significantly changed after eight hours at room temperature. Our study successfully validated the non-invasive measurement of fGCM as a stress indicator in Common Buzzards and could therefore lay the foundation for future studies providing new insights for animal welfare research in Buzzards. [ABSTRACT FROM AUTHOR]

Simple Summary: Some species of Sarcocystis parasites form cysts in the brains of small mammals. These parasites have been shown in laboratory experiments to be transmitted by Buteo buzzards. However, there is a lack of studies identifying these parasites in natural definitive hosts. In the current investigation, we examined brain tissues of small mammals and small intestines of two buzzard species collected in Lithuania for Sarcocystis spp. Species of Sarcocystis were confirmed using DNA sequence analysis. Of the eleven small mammal species inspected, only bank voles were infected with cysts of Sarcocystis glareoli. The prevalence of this parasite in the brain of vole hosts reached 9.1%. Based on genetic examination, half of the investigated common buzzards were positive for S. glareoli. Furthermore, two Sarcocystis species, including a putative new species, were detected in the small intestines of rough-legged buzzards. Our results indicate that Buteo buzzards play an important role in transmitting rarely studied Sarcocystis parasites forming cysts in the tissues of small mammals. Representatives of the genus Sarcocystis are worldwide distributed apicomplexan parasites characterised by two-host prey-predator relationships. Sarcocystis spp. produce sarcocysts in the muscles and brains of intermediate hosts and develop sporocysts in the intestines of definitive hosts. Two species, Sarcocystis glareoli and Sarcocystis microti, previously assigned to the genus Frenkelia, form cysts in the brains of rodents and are transmitted through the common buzzard (Buteo buteo). In our study, brain samples of 694 small mammals caught in different regions of Lithuania were examined for Sarcocystis spp. Additionally, 10 B. buteo and two rough-legged buzzards (Buteo lagopus) were tested for sporocysts of the analysed parasites. Sarcocystis species were identified based on 28S rRNA sequence comparison. Of the eleven species of small mammals tested, Sarcocystis parasites were observed only in the bank vole (Clethrionomys glareolus). Cysts of S. glareoli were detected in 34 out of 374 C. glareolus (9.1%, 95% CI = 6.4–12.5%). Molecular investigation showed the presence of only S. glareoli in the intestines of 50% of B. buteo. Furthermore, two species, Sarcocystis sp. Rod3 and Sarcocystis sp. Rod4, were confirmed in B. lagopus. Our results demonstrate the need for further studies on Sarcocystis cycling between rodents and birds. [ABSTRACT FROM AUTHOR]

The article focuses on the observation of Grey-faced Buzzards landing on a ship during their spring migration, a behavior not previously documented in this species or other raptors. Topics include the challenges of migrating over water bodies, the ecological and migratory patterns of Grey-faced Buzzards, and the details of the observed behavior and its potential significance for understanding migration strategies.

The geographic distribution of the Long-legged Buzzard (Buteo rufinus) in Europe has expanded during the last decades. The aim of our study is to (1) gather a comprehensive dataset regarding the presence of the Long-legged Buzzard in Romania, including all the available historical (i.e., before the year 2000) and recent observations (i.e., between 2001–2023), to (2) map Long-legged Buzzards' observations, and to (3) show the occurrences of the species according to phenological periods of the year, in the different regions of Romania. Historical occurrence data are available from 1891. Using this data, we mapped the distribution of the Long-legged Buzzards between 1891 and 2000, and found that the species was present during this period in the similar regions of Romania as the ones from where recent observations were undertaken, i.e., between 2001 to 2023. However, after the year 2000 considerably more observations are available, indicating a potential expansion of the species and/or an increased sampling effort. Furthermore, contrary to the previous assumptions, our data revealed that the species is present in recent time in each phenological period of the year, that is, pre-breeding, breeding, post-breeding, wintering, in all regions. Overall, our comprehensive dataset may be the foundation of future works aiming to reveal details about the potential expansion rate, and the temporal and spatial distributions of the species over the last century. [ABSTRACT FROM AUTHOR]

Let p be a prime number. Continuing and extending our previous paper with the same title, we prove explicit rates of overconvergence for modular functions of the form E k ∗ V (E k ∗) where E k ∗ is a classical, normalized Eisenstein series on Γ 0 (p) and V the p-adic Frobenius operator. In particular, we extend our previous paper to the primes 2 and 3. For these primes our main theorem improves somewhat upon earlier results by Emerton, Buzzard and Kilford, and Roe. We include a detailed discussion of those earlier results as seen from our perspective. We also give some improvements to our earlier paper for primes p ≥ 5 . Apart from establishing these improvements, our main purpose here is also to show that all of these results can be obtained by a uniform method, i.e., a method where the main points in the argumentation is the same for all primes. We illustrate the results by some numerical examples. [ABSTRACT FROM AUTHOR]

The recovery of some predator species in recent decades has intensified conflicts between humans and predators. To mitigate these conflicts, knowledge of predator-prey relationships is needed. The aim of this study was to estimate the predation rate of common buzzards Buteo buteo on young brown hares Lepus europaeus and to compare the magnitude of this predation between two areas that differ in the type of agricultural landscape, i.e. the size of crop fields. In the years 2005–2014, the composition of buzzard diet was studied in western Poland by analysing pellets and prey remains of nestlings and adult birds (7971 prey items identified) and estimating the abundance of buzzards (searching for and observing their nests) and hares (spotlight counts) in two adjacent areas (75 km2 in total) with small and large fields. The diet of common buzzards was dominated by common voles Microtus arvalis, and the frequency of hares ranged from 1.1% of prey items in the nestling diet to 0.2% in the diet of post-breeding individuals. The total number of hares consumed by buzzards during the spring-summer season in the whole study area amounted to 2.94 per km2, which is equal to 7.8–15.3% of the young hares born per km2. However, the predation rate estimated based on the nestling food was 2.6 times lower in small fields than in large fields. Thus, this study suggests that reducing buzzard predation on young hares can be achieved by habitat management, i.e. the creation of agricultural landscapes with numerous field boundaries. [ABSTRACT FROM AUTHOR]

Simple Summary: We compared the foraging techniques of Common Buzzards and Rough-legged Buzzards on their wintering grounds in east-central Poland. Both buzzard species spent the most time standing on the ground, less perching on trees and even less perching on fence posts. The difference in the hunting behaviors of the two species is associated with the use of small fence posts around pastures as hunting sites, which were conspicuously avoided by the Rough-legged Buzzards. Snow cover was the only weather factor in both buzzard species that affected foraging behavior and possibly intensified interspecific competition. Birds wintering in the northern Palearctic compensate for substantial energy losses and prepare for a food deficit in winter by adjusting their foraging behavior. Apart from weather conditions, interspecific competition also drives hunting strategies. To describe this phenomenon, we observed the behavior of two sympatrically wintering raptor species: the Common Buzzard and the Rough-legged Buzzard. The study was carried out in east-central Poland during four seasons on a study plot where the densities of both species were high. Interspecific differences were detected in the use of available hunting sites. Rough-legged Buzzards conspicuously avoided using fence posts for scanning the surroundings and spent the most time standing on the ground. Common Buzzards more often used trees for this purpose when the snow cover was thick. Thicker snow cover resulted in fewer attempted attacks on prey in both species and caused Common Buzzards to change their hunting sites less frequently. The study also showed that the more often a bird changed its hunting site, the greater the number of attempted attacks. The outcome is that the ultimate effectiveness of hunting is mediated by the overview of the foraging area from different heights and perspectives, not by the type of hunting site. Snow cover was the most important factor in modifying foraging behavior and possibly intensifying interspecific competition. [ABSTRACT FROM AUTHOR]

I show cases of atypical molt in the primaries of Harris's Hawk (Punihuteo unicinctus harrisi). Molt of the primaries in accipitrid raptors typically proceeds sequentially one feather at a time from the inner primary, PI. to the outer primary, P10. In larger species, not all primaries are replaced annually, resulting in Staffelmauser ('stepwise' or 'relay' molt). From 2002 to 2022.1 captured 545 Harris's Hawks in south Texas, either undergoing or having finished third prebasic molt or older, undergoing the second prebasic molt, or in Basic II plumage. 1 report herein on 6 instances in which 1 or more primaries were skipped or replaced out of order during the annual molt in Harris's Hawk: 5 undergoing the second prebasic molt and 1 undergoing third prebasic molt. I found 1 published case of skipped primaries in Griffon Vultures (Gyps fulvus) and another in a White Stork (Ciconia ciconia). One possible cause of this could be damaged primary follicles. Received II March 2022. Accepted 17 September 2022. Key words: out-of-order primary molt, skipped primary molt. Muestro casos de muda atipica en las primarias del halcon Parabuteo unicinctus harrisi. La muda de las primarias en rapaces accipitridos procede tipicamentc de manera secuencia!. una pluma a la vez a partir de la primaria interna. PI, hacia la primaria externa. PIO. En las especies mas grandes. no todas las primarias son rccmplazadas anualmente. lo que resulta en una Staffelmauser (muda 'por etapas' o 'relevos'). Del 2002 al 2022, capture 545 halcones de Harris en el sur de Texas, ya sea que estaban durante o al final de su tercera muda prcbasica o de mas edad, que esten realizando la segunda muda prcbasica o que esten en el plumaje basico II. Aqui reporto 6 instancias en las que 1 o mas primarias fueron sahadas o reemplazadas en desorden durante la muda anual en halcones de Harris: 5 durante la segunda muda prehasica y I durante la tercera muda prebasica. Encontre 1 repone publicado de primarias saltadas en buitrcs Gyps tubus y otro en cigiienas Ciconia ciconia. Una posiblc causa de esto serian foliculos primarios danados. Palabras clave: muda primaria desordenada. salto de muda primaria., Molt of the primaries in accipitrid raptors begins with the innermost feather (PI; primary molt center) every annual molt cycle. Molt proceeds sequentially in a wave with the next primary, [...]

Counts of galaxy clusters offer a high-precision probe of cosmology, but control of systematic errors will determine the accuracy of this measurement. Using Buzzard simulations, we quantify one such systematic, the triaxiality distribution of clusters identified with the redMaPPer optical cluster finding algorithm, which was used in the Dark Energy Survey Year-1 (DES Y1) cluster cosmology analysis. We test whether redMaPPer selection biases the clusters' shape and orientation and find that it only biases orientation, preferentially selecting clusters with their major axes oriented along the line of sight. Modelling the richness–mass relation as log-linear, we find that the log-richness amplitude ln (A) is boosted from the lowest to highest orientation bin with a significance of 14σ, while the orientation dependence of the richness-mass slope and intrinsic scatter is minimal. We also find that the weak lensing shear-profile ratios of cluster-associated dark haloes in different orientation bins resemble a 'bottleneck' shape that can be quantified with a Cauchy function. We test the correlation of orientation with two other leading systematics in cluster cosmology – miscentering and projection – and find a null correlation. The resulting mass bias predicted from our templates confirms the DES Y1 finding that triaxiality is a leading source of bias in cluster cosmology. However, the richness-dependence of the bias confirms that triaxiality does not fully resolve the tension at low-richness between DES Y1 cluster cosmology and other probes. Our model can be used for quantifying the impact of triaxiality bias on cosmological constraints for upcoming weak lensing surveys of galaxy clusters. [ABSTRACT FROM AUTHOR]

The study of a nest of Long-legged Buzzard Buteo rufinus was carried out using a trail camera and is one piece of a completely unknown jigsaw puzzle of diet and nesting behaviour in Romania. With a hatching success of 75%, we identified 3 hatched chicks from the 4 eggs. During the 10 days of monitoring, 34 preys brought to the nest were identified, with a peak of activity between 11:00--17:00 and a preference for the European Ground Squirrel Spermophilus citellus (61.76%). This was followed by the Domestic Pigeon Columba livia f. domestica and the Common Wood Pigeon C. palumbus (5.88%), and amphibians were represented by the European Green Toad Bufotes viridis (2.94%). There were 10 unidentified prey species (29.41%). We identified the presence of plastic and textile fibres in the nest and the risk of chick suffocation. We also improved our understanding of interspecific interactions and our observations highlighted the mutualism between the three species in the nest: Spanish Sparrow, House Sparrow and LLB. The removal of solitary trees from the agricultural landscape is a major threat in south-western Romania, affecting the breeding population of the LLB, which, as in our case, nests on this type of support. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Let p ≥ 5 be a prime, and let f be a cuspidal eigenform of weight at least 2 and level coprime to p of finite slope α. Let ρ ̄ f denote the mod p Galois representation associated with f and ω the mod p cyclotomic character. Under an assumption on the weight of f , we prove that there exists a cuspidal eigenform g of weight at least 2 and level coprime to p of slope α + 1 such that ρ ̄ f ⊗ ω ≃ ρ ̄ g , up to semisimplification. The proof uses Hida–Coleman families and the theta operator acting on overconvergent forms. The structure of the reductions of the local Galois representations associated to cusp forms with slopes in the interval [ 0 , 1) were determined by Deligne, Buzzard and Gee and for slopes in [ 1 , 2) by Bhattacharya, Ganguli, Ghate, Rai and Rozensztajn. We show that these reductions, in spite of their somewhat complicated behavior, are compatible with the displayed equation above. Moreover, the displayed equation above allows us to predict the shape of the reductions of a class of Galois representations attached to eigenforms of slope larger than 2. Finally, the methods of this paper allow us to obtain upper bounds on the radii of certain Coleman families. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine the structure of the spleen in the long‐legged buzzard (Buteo rufinus) by histologically and the distribution of the catalase in the spleen by immunohistochemically. The tissue materials were taken from three healthy long‐legged buzzards provided by permission of the General Directorate of Nature Protection and National Parks (Ankara, Turkey). The long‐legged buzzard spleen is surrounded by smooth muscle cells and fibrous connective tissue. In addition, trabecular structures are not found in the capsule. The separation of white and red pulp areas could not be precisely determined. Plasma cells were detected especially around the lymphoid follicles and lymphatic follicles and Schweigger‐Seidel cells were formed by reticulum strands. Alcian blue positive reaction was determined in Schweigger‐Seidel cells and endothelial cells of the long‐legged buzzard spleen. The intense cytoplasmic catalase immunoreactivity was observed in the Schweigger‐Seidel cells and nuclear in some red pulp cells of the long‐legged buzzard spleen. Consequently, determination of the histological structure and catalase immunoreactivity of the spleen on the long‐legged buzzard by this study could be support for the future researches. [ABSTRACT FROM AUTHOR]

Retrospective comparison of predictive models that describe competing hypotheses regarding system function can shed light on regulatory mechanisms within the framework of adaptive resource management. We applied this approach to a 28‐year study of red grouse (Lagopus lagopus scotica) in Scotland, with the aims of reducing uncertainty regarding important drivers of grouse population dynamics, and of evaluating the efficacy of using seasonal versus annual model assessments. We developed three sets of models that predicted pre‐breeding and post‐breeding grouse density, matching the timing of grouse counts on the ground. We updated conditions and management through time in the spirit of a real‐time, adaptive management program and used a Bayesian model weight updating process to compare model predictions with empirical grouse densities. The first two model sets involved single annual updates from either pre‐breeding or post‐breeding counts; the third set was updated twice a year. Each model set comprised seven models representing increasingly complex hypotheses regarding potentially important drivers of grouse: the baseline model included weather and parasite effects on productivity, shooting losses and density‐dependent overwinter survival; subsequent models incorporated the effect of habitat gain/loss (HAB), control of non‐protected predators (NPP) and predation by protected hen harriers (Circus cyaneus, HH) and buzzards (Buteo buteo, BZ). The weight of evidence was consistent across model sets, settling within 10 years on the harrier (NPP + HH), buzzard (NPP + HH + BZ) and buzzard + habitat (NPP + HH + BZ + HAB) models, and downgrading the baseline + habitat, non‐protected predator, and non‐protected predator + habitat models. By the end of the study only the buzzard and buzzard + habitat models retained substantial weights, emphasizing the dynamical complexity of the system. Habitat inclusion failed to improve model predictions, implying that over the period of this study habitat quantity was unimportant in determining grouse abundance. Comparing annually and biannually assessed model sets, the main difference was in the baseline model, whose weight increased or remained stable when assessed annually, but collapsed when assessed biannually. Our adaptive modeling approach is suitable for many ecological situations in which a complex interplay of factors makes experimental manipulation difficult. [ABSTRACT FROM AUTHOR]

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Interspecific competition occurs when two sympatric species utilize the same limited supply of a basic resource, such as food; the degree of diet overlap is an essential metric for examining potential competition between the species. The Long-legged Buzzard (Buteo rufinus) is a relative newcomer to the island of Cyprus, where it is sympatric with the larger Bonelli's Eagle (Aquila fasciata), a potential competitor for both food and space (nesting territories). We studied the diet of the Long-legged Buzzard in the 2005, 2006, and 2018 nesting seasons through analysis of pellets and prey remains collected at 38 sites. The most abundant prey class was mammals (68.8% frequency, 58.9% biomass), followed by reptiles (16.8% frequency, 36.3% biomass), and birds (4.3% frequency, 4.6% biomass). The most numerous prey species were black rats (Rattus rattus), starred agamas (Stellagama stelio), house mice (Mus musculus), and large whip snakes (Dolichophis jugularis), but in terms of biomass, the most important prey items were black rats, large whip snakes, long-eared hedgehogs (Hemiechinus auritus dorotheae), and starred agamas. We compared the diet of the Long-legged Buzzard to that of the Bonelli's Eagle, whose diet was dominated by birds (62.1% frequency, 76.1% biomass) and to a lesser degree by mammals (29.5% frequency, 21.9% biomass). The mean prey biomass for the Long-legged Buzzard was estimated as 167 g, compared to 350 g for the Bonelli's Eagle; this difference reflected the almost two-fold difference in mass between females of the two species. Diet overlap measured with Pianka's index was <0.5, suggesting an intermediate niche overlap mainly due to utilization of an abundant prey resource, such as the black rat. Niche breadth for the Long-legged Buzzard measured using Levins' index ranged from 0.485 in 2005 to 0.081 in 2018. This decrease in niche breadth over time in a generalist species can occur when there is a superabundance of a particular prey. The mean Levins' index for the Bonelli's Eagle was also low, 0.271 (1999–2001). Based on the diet comparison, we concluded that there was no evidence for interspecific competition in terms of food. La competencia interespecífica ocurre cuando dos especies simpátricas utilizan el mismo suministro limitado de un recurso básico, como por ejemplo la comida; el grado de solapamiento de la dieta es una métrica esencial para examinar la competencia potencial entre las especies. Buteo rufinus es una especie relativamente nueva en la isla de Chipre, donde se presenta en simpatría con Aquila fasciata, de mayor tamaño, un competidor potencial tanto por comida como por espacio (territorios de nidificación). Estudiamos la dieta de B. rufinus en las temporadas de cría de 2005, 2006 y 2018 mediante el análisis de egagrópilas y restos de presas recolectados en 38 sitios. Las presas más abundantes fueron los mamíferos (68,8% de frecuencia, 58,9% de biomasa), seguido de los reptiles (16,8% de frecuencia, 36,3% de biomasa) y las aves (4,3% de frecuencia, 4,6% de biomasa). Las especies de presa más numerosas fueron Rattus rattus, Stellagama stelio, Mus musculus y Dolichophis jugularis, si bien en términos de biomasa las presas más importantes fueron R. rattus, D. jugularis, Hemiechinus auritus dorotheae y S. stelio. Comparamos la dieta de B. rufinus con la de A. fasciata, cuya dieta estaba dominada por aves (62,1% de frecuencia, 76,1% de biomasa) y en menor medida por mamíferos (29,5% de frecuencia, 21,9% de biomasa). La biomasa de la presa promedio para B. rufinus se estimó en 167 g, en comparación con 350 g para A. fasciata; esta disparidad reflejó la diferencia de masa de casi el doble entre las hembras de las dos especies. El solapamiento de dieta medido con el índice de Pianka fue <0,5, lo que sugiere un solapamiento de nicho intermedio debido principalmente a la utilización de un recurso de presa abundante como R. rattus. La amplitud de nicho para B. rufinus, medido con el índice de Levins, fluctuó entre 0,485 en 2005 y 0,081 en 2018. Esta disminución en la amplitud de nicho a lo largo del tiempo en una especie generalista puede ocurrir cuando hay una sobreabundancia de una presa en particular. El índice de Levins medio para A. fasciata también fue bajo, 0,271 (1999–2001). Basados en la comparación de la dieta, concluimos que no hubo evidencia de competencia interespecífica en términos de alimentación. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

In the present study, lead, zinc and copper concentrations in the feathers of Common kestrel (Falco tinnunculus), Eurasian magpie (Pica pica), Common buzzard (Buteo buteo), Crested lark (Galerida cristata), Eurasian hoopoe (Upupa epops), Little owl (Athene noctua), Long-eared owl (Asio otus), Eurasian eagle-owl (Bubo bubo) and Long-legged buzzard (Buteo rufinus) from Sabzevar and Neghab, Khorasan Razavi of Iran were measured. Almost all of the specimens were obtained from birds that had collided with vehicles or were unable to fly. There were no significant differences in metal concentrations between adult and juvenile, diurnal and nocturnal raptors and species with different diets. Elemental concentrations were lower than toxicity threshold values, so exposure to these elements does not appear to pose a health risk to the studied species. It should be noted that this study was the first study of metals in Galerida cristata, Asio otus and Buteo rufinus. [ABSTRACT FROM AUTHOR]

Even though the mechanical behavior of granular soil–rubber mixtures has attracted significant attention and promising applications in geotechnical engineering, less attention has been paid to the influence of creep and long-term response of these composites. The present study examined the compression behavior of two types of sands mixed with recycled granulated rubber with emphasis on the influence of rubber percentage and sand grain type, providing in this way some new insights with emphasis on creep influences. One natural material is composed of Leighton Buzzard quartz sand of noncrushable grains, and the second material is composed of completely decomposed granite of crushable grains (note that the terms crushable and noncrushable refer to the range of maximum overburden pressures applied in the study that ranged from 0.3 to 6.7 MPa). The influence of creep on the compression behavior of the samples was associated with the location (or not) of the pure sand and their mixtures on the normal compression line (NCL) when creep deformations were evaluated. In specific, the rate of creep deformation was found to be independent of the stress level as long as the sample had reached its NCL during compression. Even though for LBS–rubber, there was a clear decrease of the stiffness of the mixtures expressed with the constrained modulus, this was not the case for the CDG–rubber mixtures, and within the scatter of the data, the ratio of creep index to compression index fell in a relatively narrow range (0.005–0.05), suggesting that the creep deformations could be predicted based on conventional oedometer tests with short-term measurements of the applied normal stress. [ABSTRACT FROM AUTHOR]

Simple Summary: Many wild animals, and particularly birds, are commonly infected and can suffer health consequences by blood parasites related to Plasmodium, the causative agents of malaria in humans. Atovaquone–proguanil (Malarone®, GlaxoSmithKline) is one of the most popular drugs for the treatment of malaria infections in humans and is commonly used for the treatment of birds in captivity. Our aim was to test the potential effects of Malarone® within one week of treatment on the growth rate, body condition, and blood chemistry of common buzzard nestlings, a widely distributed Eurasian bird of prey. We found no evidence of detrimental effects of a single dose in common buzzard nestlings with an average dosage of 11 mg/kg, compared with the 7 mg/kg recommended daily dosage in humans. Although Malarone® is commonly used in wildlife rehabilitation centres, and our results do not indicate acute toxicity, further studies are needed to determine the half-life and potential long-term effects of Malarone® treatment in birds. Differences in drug tolerability among vertebrate groups and species can create substantial challenges for wildlife and ex situ conservation programmes. Knowledge of tolerance in the use of new drugs is, therefore, important to avoid severe toxicity in species, which are both commonly admitted in veterinary clinics and are of conservation concern. Antimalarial drugs have been developed for use in human medicine, but treatment with different agents has also long been used in avian medicine, as haemosporidian infections play a major role in many avian species. This study investigates the effects of the application of atovaquone–proguanil (Malarone®, GlaxoSmithKline) in common buzzards (Buteo buteo). The potential effects of treatment on body condition, growth rate, and chemical blood parameters of nestlings were assessed. All individuals survived the treatment, and no effects on body condition, growth rate, and chemical blood parameters were observed. Our results suggest the tolerability of Malarone® in common buzzards at a single dose of on average 11 mg/kg body weight. For its safe use, we recommend further studies to determine pharmacokinetics in different avian species as well as to assess the effects of repeated treatment. [ABSTRACT FROM AUTHOR]

Vulture and raptor populations have declined across West Africa during recent decades due to numerous and widespread anthropogenic threats. To estimate encounter rates of vultures and raptors in northern Nigeria, we conducted a total of 248 km driven transects on 195 km and 53 km of paved and unpaved roads, respectively. We also conducted walked surveys beneath 79 km of power transmission lines to search for dead vultures and raptors; and visited 12 abattoirs, 11 slaughterhouses, and 12 dumpsites to assess the occurrence of vultures and raptors. All fieldwork was done between October and December 2018. Overall, 357 individuals of 23 species were detected, most of which were recorded at low encounter rates. Only one Hooded Vulture Necrosyrtes monachus was recorded across all surveys, and no other vulture species were seen. Yellow-billed Kite Milvus aegyptius, Grasshopper Buzzard Butastur rufipennis, and Black-winged Kite Elanus caeruleus had the highest encounter rates of 0.351, 0.262, and 0.189 individuals km-1, respectively. In contrast, the largest raptor species, Booted Eagle Hieraaetus pennatus, Short-toed Snake Eagle Circaetus gallicus, Beaudouin's Snake-eagle, and Bateleur Terathopius ecaudatus had the lowest encounter rate of 0.004 individuals km-1 (one individual each). No dead vultures or raptors were found during the walked surveys beneath power lines. Although historical data about vulture and raptor distribution and abundance in northern Nigeria are limited, our results show an apparent absence of vultures from the wider landscape and a low density of raptors. Support among local stakeholders for the conservation of vultures and raptors should be encouraged through wider dissemination of information about the importance of these birds, as well as stronger deterrents again illegal killing and trade. [ABSTRACT FROM AUTHOR]

Releasing gamebirds in large numbers for sport shooting may directly or indirectly influence the abundance, distribution and population dynamics of native wildlife. The abundances of generalist predators have been positively associated with the abundance of gamebirds. These relationships have implications for prey populations, with the potential for indirect impacts of gamebird releases on wider biodiversity. To understand the basis of these associations, we investigated variation in territory size, prey provisioning to chicks, and breeding success of common buzzards Buteo buteo, and associations with variation in the abundances of free‐roaming gamebirds, primarily pheasants Phasianus colchicus, and of rabbits Oryctolagus cuniculus and field voles Microtus agrestis, as important prey for buzzards. The relative abundance of gamebirds, but not those of rabbits or voles, was weakly but positively correlated with our index of buzzard territory size. Gamebirds were rarely brought to the nest. Rabbits and voles, and not gamebirds, were provisioned to chicks in proportion to their relative abundance. The number of buzzard chicks increased with provisioning rates of rabbits, in terms of both provisioning frequency and biomass, but not with provisioning rates for gamebirds or voles. Associations between the abundances of buzzards and gamebirds may not be a consequence of the greater availability of gamebirds as prey during the buzzard breeding season. Instead, the association may arise either from habitat or predator management leading to higher densities of alternative prey (in this instance, rabbits), or from greater availability of gamebirds as prey or carrion during the autumn and winter shooting season. The interactions between gamebird releases and associated practices of predator control and shooting itself require better understanding to more effectively intervene in any one aspect of this complex social‐ecological system. [ABSTRACT FROM AUTHOR]

The productivity of raptors is affected by different factors such as habitat, food supply, disturbance, weather conditions, and competition. Of the studied breeding parameters, success rate and breeding success significantly decreased over the years, while fledgling success and breeding density showed no trend. This study shed light on the main factors influencing the breeding success of a medium-sized raptor expanding in Europe from Asia. Modeling the factors determining the breeding success, we found that grassland availability, mean temperature during fledgling period and rainfall during nestling period influenced Long-legged buzzard reproduction (ΔAIC = 0.00, wi = 0.42, p = 0.03). The second significant model was described by weather factors excluding presence of grasslands (ΔAIC = 1.03, wi = 0.25, p = 0.05). Examining the explanatory factors, only presence of grassland in the territories demonstrated some effect on buzzard productivity. The assumption that other factors such as human disturbance, Souslik density, habitat diversity, and presence of competitors shaped buzzard's productivity did not find support in this study. This study supports the prediction of the future of Long-legged buzzard as it explored the effects of habitat and weather on its reproduction in the southern part of its distribution range. The conditions of a large-scale habitat alteration on one hand and, on the other hand, global climate change, manifested in increased rainfall during spring in Europe, draw an uncertain future for this species. Therefore, restoration of grasslands and proper habitat management, ensuring sufficient and diverse prey, is crucial for conservation of the Long-legged buzzard. [ABSTRACT FROM AUTHOR]

A free ranging, fledged common buzzard (Buteo buteo) was found with severe feather damage and left periorbital swelling. Clinical examination revealed a 3.0 × 2.5 × 1.5 cm left medial subconjunctival mass. The abnormal tissue extended over most of the left cornea, severely impairing the bird's vision in that eye. Additionally, the left globe was displaced in a temporal direction. Computed tomography revealed the origin of the mass to be retrobulbar tissue. An ultrasound examination of the mass found cystic areas, and a sanguineous fluid was aspirated. Cytological examination of the aspirated fluid revealed numerous erythrocytes and a few round cells with oval nuclei, single large nucleoli, and abundant foamy cytoplasm. After a poor prognosis for rehabilitation to the wild, the bird was humanely euthanatized. A postmortem examination of the bird confirmed the retrobulbar mass with extension around the bulbus. Histological examination of the mass was consistent with an invasive adenocarcinoma, likely arising from the lacrimal glands. Neoplasia in the orbit has occasionally been described in Psittaciformes, but only rarely in birds of prey such as Accipitriformes. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) in wild birds is a major emerging disease, and a cause of increased mortality during outbreaks. The Common buzzard (Buteo buteo) has a considerable chance of acquiring the infection and therefore may function as bio-sentinel for the presence of virus in wildlife. This study aimed to determine the virus distribution and associated pathological changes in the tissues of Common buzzards that died with HPAI H5 virus infection during the 2020–2021 epizootic. Eleven freshly dead, HPAI H5 virus-positive Common buzzards were necropsied. Based on RT-PCR, all birds were systemically infected with HPAI H5N8 virus, as viral RNA was detected in cloacal and pharyngeal swabs and in all 10 selected tissues of the birds, with mean Ct values per tissue ranging from 22 for heart to 32 for jejunum. Based on histology and immunohistochemistry, the most common virus-associated pathological changes were necrotizing encephalitis (9/11 birds) and necrotizing myocarditis (7/11 birds). The proventriculus of two birds showed virus-associated necrosis, indicating tropism of this virus for the digestive tract. Our advice is to collect at least a miniset of samples including brain, heart, liver, and spleen, as these tissues were positive both by RT-PCR and for virus-antigen-associated lesions. [ABSTRACT FROM AUTHOR]

Oriental honey buzzards (OHBs, Pernis ptilorhynchus) are one of migratory raptor from Japan to Indonesia which is widely recognized as indicator species reflecting the conditions of their habitat. Since 2003, OHBs have been satellitetracked in their wintering grounds in Indonesia. Less information available on wintering areas in the west Java, which hampers the OHB conservation efforts. This paper proposes a new approach for predicting the probability models of the wintering habitat distribution of OHBs with the presence data derived from satellite tracking using logistic regression analysis coupled with RAMAS GIS. This spatial model was locally constructed from the data concerning Talaga Bodas and its surrounding areas and extrapolated for the entire West Java region. The best predicted probability model successfully characterized the distribution of the OHB wintering habitat using slope (25-40%), elevation (0-300 m and >1,000 m), and land cover (forest, paddy field, and water body). The extrapolation model generated potential areas of the wintering habitat distribution covering an area of 3013.13 km2 (8.11% of West Java). These areas were predominantly located outside the protected areas (94.04%). The modeling approach proposed herein may be used to study other migratory species that are tracked using satellite or other navigation technologies. [ABSTRACT FROM AUTHOR]

The increase in the number of Common Buzzards (Buteo buteo) in the Náchod district, Hradec Králové region, in the 1970s and 80s resulted in a noticeable expansion of breeding pairs into the non-forest environment of floodplains of the lower reaches of the Úpa and Metuje rivers, characterized by little forest cover but a rich representation of woody species in non-forest formations, a high proportion of meadows and perennial fodder crops and a minimal proportion of maize and rapeseed. Nests were searched there in March and April before the trees were leaved out, and then their occupancy by the Common Buzzard was verified as necessary. In the year 1990, 53 breeding pairs/100 km² were found there. After 1990, however, more than 40% of the meadows were gradually plowed up in this area, and at the same time, the share of crops unsuitable for Common Voles, the main food source of buzzards, increased several times. Despite the overall decrease in the number of Common Buzzards in the Náchod district by 10– 20% and the permanent decrease in the biodiversity of the agricultural landscape, a density of 56 breeding pairs/100 km² was found in the monitored river floodplains in 2021. Even after unfavorable changes in farmland, river floodplains remain the most suitable environment for Common Buzzards in the Náchod district, thanks to the preservation of a suitable combination of habitat and food conditions. [ABSTRACT FROM AUTHOR]

The results of long-term monitoring of the long-legged buzzard, which nests in artificial tree–shrub communities of the clay semidesert of the Trans-Volga region, are presented. Observations, which started in the 1980s and were carried out in the Pallas district of the Volgograd oblast (Russia) and in the West Kazakhstan oblast (Republic of Kazakhstan), show that the lack of natural objects suitable for nest building made this bird dependent on human activity. The forest belts created in the 1950s–1970s dramatically expanded the potential nesting area of the long-legged buzzard and brought it out of local habitats like lake basins and spiraea gullies into the zonal plain. Here, around transportation routes and in the environs of settlements in the areas especially strongly developed by man, first a stable and then an oversized population of this bird was formed by the beginning of the 21st century. Since the 2010s there has been a decrease in the numbers of nesting birds, the reason for which being a drop in the numbers of ground-squirrels and the development of a tall-grass cover, thus making it difficult for birds to find prey. The degradation of artificial plantations deprived of care still renders little effect on the numbers of nesting pairs. Birds stubbornly maintain the preferred distance between the nests of 1.5–2 km. A decrease in this distance is noted sporadically, indicating both a shortage of nesting places and a high food capacity of the territory. [ABSTRACT FROM AUTHOR]

Aristotle in his anatomical observations is marking the beginning of functional anatomy followed by Georges Cuvier that formulate the low of the correlation of parts. According with this we can expect that the digestive system structures tend to be similar between species that consume approximately the same type of food. In this study we chose to evaluate macroscopic the digestive system of two different zoophytophagous species, with similar body size but different life behavior and feeding strategies: White Stork (Ciconia ciconia) and Common Buzzard (Buteo buteo). Data were collected after the dissection of 10 carcass (5 White Stork and 5 Common Buzzard). The digestive tract and its structures were measured and weighed. In common buzzard the beak is strong and short adapted for the laceration of the prey. In white stork the beak is long, strong, straight adapted to capture prey like a harpoon. In both species, the esophagus is located on the right side of the neck, the length is different, proportional to the neck. In common buzzard the crop is present and absent in white storks. The cuticle or koilin layer is highlighted in white stork compared to common buzzard. In common buzzard, the small intestine is reduced in size, without marked transition between the duodenum and the ileum. The white storks have a long small intestine with many loops, with no transition between the segments. In both species, the cecum is reduced in size and has a vestigial appearance; the colon is reduced in size, and extends from the level of the ileo-colic junction to the cloaca. The digestive system is adapted to a strictly carnivorous diet and the differences identified between the anatomical structures of the digestive tract of the two species are correlated with the differences of their feeding behavior. [ABSTRACT FROM AUTHOR]

To determine large scales habitat suitability for focal species, habitat models derived from one region are often extrapolated to others. However, extrapolation can be inappropriate due to regional variation of habitat selection. Accounting for the ecological mechanisms causing such variation is necessary to resolve this problem. We focused on grey-faced buzzards in agricultural landscapes of Japan, which show geographically different habitat selection. To determine whether this variation is caused by the difference in climatic conditions at geographical scales or the difference in agricultural practices at smaller regional scales, we surveyed distributions of buzzards and their major prey (frogs/orthopterans) in regions differing in rice-transplanting schedules within the same climatic zone. We found that buzzards preferred paddy-forest landscapes in the early transplanting regions, but grassland-forest landscapes in the late transplanting regions. Frogs were more abundant in the early transplanting regions due to flooded paddies, while the abundance of orthopterans did not differ. The regional variation in habitat selection of buzzards may be due to different prey availabilities caused by different agricultural schedules. We propose that habitat suitability assessments of organisms inhabiting agricultural landscapes should consider differences in production systems at regional scales and such regional partitioning is effective for accurate assessments. [ABSTRACT FROM AUTHOR]

Raptor cognition has received limited research attention, despite the importance of comparative investigations for reconstructing the evolution of complex cognition. Field studies provide essential ecological context for cognition in the natural habitat, although this approach is often challenging due to extensive procedures involved in cognitive testing. One predisposition suggested to contribute to problem-solving behaviour is the response to novel stimuli. In this pilot study, a novel object test was conducted on an outdoor feeding platform to assess the neotic responses of a single wild free-ranging Common Buzzard (Buteo buteo), a generalist/opportunist diurnal predator species. Additionally, data on its daily activity were collected. As predicted, the subject expressed low neophobia and some exploratory behaviours. Interestingly, it repeatedly arrived on the platform in low light conditions. This study highlights the influence of foraging ecology on cognitive predispositions and offers a field method for research on raptor cognition. [ABSTRACT FROM AUTHOR]

We describe a new species of a large buzzard (Accipitridae), Buteo dondasi sp. nov. from the late Pliocene of Buenos Aires Province, Argentina represented by an incomplete left hind limb, including a distal fragment of tibiotarsus, tarsometatarsus, fragment of os metatarsale I, and toes I and II. The new taxon exhibits characteristics of the crown group Accipitridae and the shape of the tarsometarsus allows its assignment to the genus Buteo. The new species represents the very first record of a representative of a non-scavenging diurnal bird of prey for the Chapadmalalan and one of the largest accipitrids (~ 2.3 kg) known for Argentina. [ABSTRACT FROM AUTHOR]

Background: The rufous-winged buzzard (Butastur liventer) belongs to the order Accipitriformes, which is monomorphic, resulting in the difficulty to identify the gender. However, sex determination is important for predicting the sex ratio of this buzzard in nature in order to avoid its extinction. Aim: We aimed to develop a primer set that is able to sex the rufous-winged buzzard through polymerase chain reaction (PCR) amplification and compare the efficacy of the two sets of primers by using PCR technique. Methods: In the following, sensitivity refers to the smallest DNA concentration that allowed us to accurately sex a bird and specificity refers to the ability to clearly distinguish the sex based on the visual appearance of the bands. Blood samples were collected from captive buzzards. The DNA was extracted from them and was diluted to 50, 25, 10, 5, 2.5, 1.67, and 1 ng/μl. Two sets of primers, including P2/NP/MP and 2550F/2718R, were used to amplify the chromo-helicase DNA binding (CHD) gene of known gender buzzards using the PCR process to determine gender and to compare their sensitivity. To measure specificity, both primers were used to amplify CHD gene fragment of other unknown gender birds. Results: The lowest concentration of the DNA template where P2/NP/MP could amplify DNA fragments was 1 ng/μl, and this set of primers could identify the gender of all birds correctly, giving 100% specificity. On the other hand, the 2550F/2718R could amplify the DNA fragments from 5 ng/μl, and it had only 78% specificity. Conclusion: The P2/NP/MP primer set was able to correctly identify the gender of rufous-winged buzzard through PCR amplification with high specificity and sensitivity. [ABSTRACT FROM AUTHOR]

In NGI-type simple shear apparatus, including recently developed NGI-type bi-directional simple shear apparatus, the complete stress state is unknown which limited the interpretation of test results. This study compares the stress state of NGI-type simple shear test obtained by two methods, the stress state determined by an empirical method using test data, and stress state determined by measured values in a corresponding DEM test. Results showed that (1) stress state obtained by the two methods shows good agreement, especially at simple initial stress conditions. (2) due to the underestimation of constant k, minor principle stress and horizontal stress interpreted by the empirical method are higher than that in DEM test, and noncoaxiality interpreted by the empirical method are lower than that in DEM test. It is recommended that before determining the stress state of NGI-type bi-directional drained simple shear tests, it is needed to perform a test and corresponding DEM test under simple stress condition. The empirical equations for horizontal stress, especially the constant k should be validated and corrected for the tested soil before interpreting the stress state. [ABSTRACT FROM AUTHOR]