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To develop an ultrasound (US)-guided ventral approach to the brachial plexus (BP) and evaluate nerve anatomy and staining in barred owl cadavers. Prospective, cadaveric study. Eleven adult male and female barred owl cadavers with a body mass of 0.43–0.98 kg. Eleven frozen cadavers were thawed for 48 hours, weighed and assigned a body condition score. Ten cadavers were placed in dorsal recumbency with wings abducted. US-guided visualization of the BP was achieved by placing a 13-6 MHz linear probe over the ventral aspect of the scapulohumeral joint, parallel to the sternum. A 22 gauge, 50 mm insulated needle was advanced in-plane in a caudal-to-cranial direction. In each owl, injection targeting one BP was performed with 0.4 mL kg–1 of a 1:1 0.5% ropivacaine and 1% methylene blue solution. Dissection was performed 15 minutes postinjection. Nerve staining was deemed successful if ≥ 1 cm of circumferential staining was achieved. The eleventh owl cadaver was injected with a 1:1 solution of 1% methylene blue and 74% ioversol contrast into both wings, and computed tomography (CT) was performed just before and 15 minutes after injection. The BP was clearly identified ultrasonographically in cadavers weighing > 0.5 kg. An injectate volume of 0.4 mL kg–1 provided complete staining of the BP branches in all cadavers. CT scan revealed no contrast within the coelomic cavity. The US-guided BP injection using a ventral approach was easily performed in barred owl cadavers weighing > 0.5 kg. The injection of 0.4 mL kg–1 of a ropivacaine–dye solution resulted in complete staining of the BP branches in all wings, suggesting that this technique could provide analgesia for structures distal to the scapulohumeral joint. Clinical studies are necessary to confirm the safety and efficacy of this technique in barred owls and other bird species. [ABSTRACT FROM AUTHOR]

Background: Tauopathies, including Alzheimer's disease, are characterized by the pathological aggregation of tau protein, which is strongly linked to dysregulation of the autophagy-lysosomal degradation pathway. However, therapeutic strategies targeting this pathway remain limited. Methods: We used both in vitro and in vivo models to investigate the role of Raptor in tau pathology. Knockdown of Raptor was performed to assess its impact on mTORC1 activation, autophagy, and tau accumulation. The relationship between USP9X and Raptor was also examined. Pharmacological inhibition of USP9X with WP1130 was employed to further confirm the involvement of the USP9X-Raptor-mTORC1 axis in tau degradation. Results: Elevated Raptor levels in the hippocampus of P301S mice led to hyperactivation of mTORC1, impairing autophagy flux. Knockdown of Raptor effectively suppressed mTORC1 activation, promoted autophagy, and mitigated the accumulation of tau and its phosphorylated isoforms. This reduction in tau pathology was accompanied by decreased neuronal loss in the hippocampus, amelioration of synaptic damage, and improvement in cognitive function. The increased Raptor protein observed in the hippocampus of P301S mice was likely attributable to elevated USP9X content, which enhanced Raptor deubiquitination and protected it from proteasomal degradation. Pharmacological inhibition of USP9X with WP1130 in vitro effectively suppressed Raptor, promoted autophagy, and accelerated the degradation of tau and phosphorylated tau. Conclusions: Our findings highlight Raptor and USP9X as promising molecular targets for therapeutic intervention in tauopathies. Targeting the USP9X-Raptor-mTORC1 axis may provide a novel strategy for promoting autophagy and mitigating tau pathology in Alzheimer's disease and other tauopathies. [ABSTRACT FROM AUTHOR]

The Grey Goshawk is an endangered raptor occurring at low densities throughout its Tasmanian range. Nesting ecology and conservation requirements of the species are poorly understood. Thus, knowledge of nest site selection and breeding habitat preferences is needed to inform conservation management strategies. Here, we investigate nest site selection in a modified anthropogenic landscape in south-east Tasmania, Australia based on 75 active nest sites. Our logistic regression models show that nest site selection is influenced by a range of variables at the landscape, nest stand and nest site level, which likely relate to territoriality, food availability and forest structure. We also used environmental and disturbance-related variables to deliver a management-specific model, which indicated distance to track, dwelling and drainage lines were significant predictors of nest site selection. Our results can be used to improve conservation management and planning strategies. [ABSTRACT FROM AUTHOR]

Feeding morphology permits animals to adapt to changing environments and is often under strong selection. We evaluated if bill shape varies according to differences in dietary prey taken across geographical ranges (North America, Central America, South America, and Caribbean islands) in a ubiquitous, New World raptor species, the American kestrel (Falco sparverius). Specifically, we predicted that bills in geographies where kestrels consumed a larger proportion of vertebrates would be shorter and wider, with a larger tomial tooth. We reviewed the literature on kestrel diets across their range and quantified potential differences in bill shape using geometric morphometric methods for 245 museum specimens. The literature review revealed that most prey consumed by kestrels in North, South, and Central America were invertebrates (51.6–69.1%), whereas Caribbean kestrels consumed mostly vertebrates (61.4%), most of which were reptiles (77.3%). Morphometric analyses agreed with these findings; bill shape differed for island versus mainland kestrels but not among mainland regions. Bill shape on islands reflected a more robust bill with a larger tomial tooth, but had a longer hook, which we suggest is adaptive for consumption of lizard prey, more available on islands due to reduced competition with other raptors compared to mainland regions. [ABSTRACT FROM AUTHOR]

Apex scavengers can perform an important ecosystem service by rapidly removing carrion, in turn regulating nutrient cycling linked to carcass decomposition. Yet, our understanding of the biotic and abiotic factors that influence rates of apex scavenging and their behaviour around carrion remains limited, in part because of the absence of replicated studies across different bioregions, habitats and seasons. Here, we examine the use of carrion by one of Australia's apex scavengers, the wedge‐tailed eagle Aquila audax, and uncover the extent and consequences of their social interactions at carrion. We applied a standardised design to monitor 120 kangaroo (Family: Macropodidae) carcasses using camera traps across contrasting bioregions (desert, forest and alpine), habitats (open and closed canopy) and seasons (warm and cool). We predicted that wedge‐tailed eagles would discover carcasses quicker in open habitats, and that intrinsic carrion value (ICV), or the desirability of carrion, would be related to dietary stress as a function of productivity and season (i.e. we expected to see increased carcass use by eagles in the less productive desert bioregion and in cooler seasons). Across all bioregions, we found that wedge‐tailed eagles discovered carcasses in open habitats 2.7 times faster than in closed habitats and 5.3 times faster in cool seasons compared with warm seasons. Scavenging was more likely to occur in open environments and was more frequent in cool seasons and in the desert bioregion. ICV largely governed social interactions; there were more aggressive encounters between wedge‐tailed eagles during cool seasons and in the desert bioregion. Our results highlight how bioregional, habitat, and seasonal variation can drive scavenging rates and social interactions between conspecific apex scavengers. Further studies considering both carrion use and corresponding behavioural interactions will enhance our understanding of how carrion contributes to shaping interactions between and within species groups as well as scavenger communities more broadly. [ABSTRACT FROM AUTHOR]

Evaluating population responses to management is a crucial component of successful conservation programs. Models predicting population growth under different management scenarios can provide key insights into the efficacy of specific management actions both in reversing population decline and in maintaining recovered populations. Bald eagle (Haliaeetus leucocephalus) conservation in the United States has seen many successes over the last 50 years, yet the extent to which the bald eagle population has recovered in Arizona, an important population within the Southwest region, remains an area of debate. Estimates of the species' population trend and an evaluation of ongoing nest‐level management practices are needed to inform management decisions. We developed a Bayesian integrated population model (IPM) and population viability analysis (PVA) using a 36‐year dataset to assess Arizona bald eagle population dynamics and their underlying demographic rates under current and possible future management practices. We estimated that the population grew from 77 females in 1993 to 180 females in 2022, an average yearly increase of 3%. Breeding sites that had trained personnel (i.e., nestwatchers) stationed at active nests to mitigate human disturbance had a 28% higher reproductive output than nests without this protection. Uncertainty around population trends was high, but scenarios that continued the nestwatcher program were less likely to predict abundance declines than scenarios without nestwatchers. Here, the IPM‐PVA framework provides a useful tool both for estimating the effectiveness of past management actions and for exploring the management needs of a delisted population, highlighting that continued management action may be necessary to maintain population viability even after meeting certain recovery criteria. [ABSTRACT FROM AUTHOR]

One of the conservation measures of the globally near-threatened cinereous vulture is restoring populations via translocations, with some vultures originating from breeding centers. These centers need to have reproductive success, and securing good welfare levels should be a priority due to the negative implications a compromised welfare has on reproduction. Thus, assessing welfare in breeding centers is essential. Remote methods should be preferred, such as behavior analysis and use of space using camera systems. The study’s first objective was to develop an activity budget that could be used as a baseline for detecting behavior irregularities. The second was to determine if behavior analysis and use of space could detect potential welfare issues in a breeding center. The study developed an activity budget that could be used as a standard for behavior analysis for the captive population. Behavior irregularities were detected, and the potential need to improve the enclosure and its surroundings were noticed. Altogether, the proposed methodology and results will contribute to the detection of possible welfare issues in breeding centers and, consequently, improve reproductive success and species’ conservation. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions The high proportion of plumage polymorphism in raptor species presents exciting research potential. Unfortunately, fundamental knowledge gaps remain that limit our ability to fully understand the development and role of plumage polymorphism in this group and extend those insights to vertebrates as a whole. We report data that fills one such knowledge gap in the red‐tailed hawk (Buteo jamaicensis) that will enable investigations to uncover factors that influence the biogeography of plumage polymorphism in the species and raptors more generally.North America.Buteo jamaicensis (red‐tailed hawk).We captured and outfitted four dark and 22 light morphs with GPS/GSM satellite transmitters during the non‐breeding season in the Great Lakes region of North America to assess their breeding provenance and behaviours. We calculated 95% AKDE nesting home ranges during an 80‐day period meant to capture the incubation and brood‐rearing periods and compared home ranges by age and sex to contextualise movements.Our results indicate that dark types nest in eastern Canada and belong to the same breeding population as the light individuals tagged in our study, extending the known distribution of plumage polymorphism in the species approximately 1500 km eastward into eastern Canada.This revised distribution of plumage polymorphism is a critical first step for understanding the biogeography of plumage polymorphism and assessing drivers of within‐population trait diversity in this species, and predatory vertebrates more generally. [ABSTRACT FROM AUTHOR]

An approximately 26‐year‐old, suspected female, red‐tailed hawk (Buteo jamaicensis) was presented with a history of chronic ocular changes of the left eye likely secondary to blunt trauma resulting in blindness and phthisis bulbi. Ophthalmic evaluation of OS revealed a large intraocular mass, 3+ aqueous flare indicating anterior uveitis, and severely decreased intraocular pressure measuring 5 mmHg. Ocular ultrasound revealed an abnormal, spherical shaped and hyperechoic lens, as well as hyperechoic material or a mass lesion in the posterior segment. An enucleation procedure was performed, and histopathology of the eye revealed no signs of neoplasia but instead intraocular osseous metaplasia with bone marrow and adipose tissue replacing the lens. Similar mass lesions were found in the retina and choroid. Multiple fractures in the scleral ossicle and cartilage correlated the intraocular lesions with a blunt traumatic event. A bioresorbable disk of porcine small intestine submucosa (BioSIS Vetrix®) was incorporated to relieve tension during closure. The graft sloughed during healing process, revealing a healed wound underneath. The BioSIS was not incorporated into the wound as designed but may have facilitated healing. This is the first report of intraocular osseous metaplasia in a raptor and the use of BioSIS Vetrix® with enucleation in an avian species. [ABSTRACT FROM AUTHOR]

Satellite tracking allows for novel investigations into golden eagle home range characteristics. Understanding home range characteristics is important for conservation and for assessing the potential impact of landscape changes from forest planting, wind farms, etc. Small sample sizes, inconsistent definitions and methods restricted several previous studies. Our study involved 69 resident tagged eagles with over one year of data across five Scottish regions. Home range size was estimated from 95% isopleth contours extracted from Utilisation Distributions. Above a small threshold, estimated range size was not affected by the number of records but at least one year of data is required, largely because of the breeding and non-breeding seasonal differences. There were no significant range size differences between birds tagged as range holders and those previously tagged as nestlings. Across four regions, with considerable intra-regional variation, planar 95% isopleths did not differ (medians, km2): Argyll 58.9, Northwest Highlands 61.7, Northeast Highlands 89.3, South of Scotland 91.9. Ranges in the isolated Outer Hebrides region were exceptionally small, at 24.0 km2. Estimated range area was usually reduced to 70–80% of the planar area when restricted to usable habitat, as estimated by the Golden Eagle Topography (GET) model. Applying measures of known unsuitable habitat (closed-canopy commercial forest and wind turbines) further reduced usable open land. Loss of otherwise suitable habitat was substantially due to commercial forest. Larger ranges had larger extents of suitable habitat (according to GET), with no apparent optimum of preferred GET habitat. Range size was not different across a year between the sexes. Breeding ranges were smaller, and females' breeding ranges were much smaller than those of males, but larger than males' ranges in the non-breeding season. Breeding attempt duration was probably also influential. Our study provides novel insights into golden eagle home range characteristics and can guide further research and practical applications. [ABSTRACT FROM AUTHOR]

Understanding how human activities affect wildlife is fundamental for global biodiversity conservation. Ongoing land use change and human‐induced climate change, compel species to adapt their behaviour in response to shifts in their natural environments. Such responses include changes to a species' diet or trophic ecology, with implications for the wider ecosystem. This is particularly the case for predatory species or those that occupy high positions within trophic webs, such as raptors. Between 2002 and 2019, we observed 1578 feeding events of the globally near threatened and understudied, Red‐necked Falcon (Falco chicquera) in Bangladesh. We explored the effects of mean monthly temperature, precipitation, temperature differences, and urban land cover on (a) mean prey weights and (b) dietary composition of 15 falcon pairs. Falcons hunted smaller prey items during months with increased temperatures and precipitation, and in more urban areas. However, during months with increased temperature differences, falcons tended to prey on larger prey items. Being specialist aerial hunters, these dietary patterns were largely driven by the probabilities of bats and birds in the diet. Falcons were more likely to prey on bats during warmer and wetter months. Furthermore, urban pairs tended to prey on bats, whereas more rural pairs tended to prey on birds. Mean monthly temperature difference, i.e., a proxy for climate change, was better at explaining the probability of bats in the falcon diet than mean monthly temperature alone. Anthropogenic dietary shifts can have deleterious effects on species with declining populations or those of conservation concern. The effects of urbanisation and human‐induced climate change are expected to continue into the foreseeable future. Therefore, our findings represent a cornerstone in our understanding of how falcons respond to an increasingly human‐dominated world. [ABSTRACT FROM AUTHOR]

Understanding a species' distribution is vital for making sound conservation and management decisions. Secretive behaviors and complicated seasonal movement patterns have made range delimitation surprisingly elusive for some North American birds, including the Northern Saw-whet Owl (Aegolius acadicus). Despite being among the most common of North American forest owls, only the species' breeding range is well demarcated. This has resulted in the species historically being considered a "northern" bird, with eastern migratory and nonbreeding ranges extending only as far south as central Missouri and eastern Tennessee. Recent banding efforts have shown that saw-whet owls are fall migrants much farther south. We extend this work by investigating stopover duration and nonbreeding habitat selection during 2 winters at the edge of the species' southern distribution in the Ozark Highlands of northwest Arkansas. We used radio telemetry to track 27 owls, with 17 individuals detected at least once post-release (n = 54 surveys and 131 total detections). Length of stay in the study area was most influenced by year—birds remained an average of 3.6 weeks longer during an irruption year—and our data suggest that the species uses the Ozark Highlands for both nonbreeding residency and brief stopover periods. During the 2 year study, 37% of marked owls were winter residents, 26% remained in the area temporarily, and 37% were not redetected. Winter habitat preferences of saw-whet owls in the southeast are consistent with what is known about the species in its more northernly range, with birds selecting conifers on south-facing slopes in areas with an open understory. Overall, our results suggest that saw-whet owls are not rare fall migrants and winter residents in Arkansas as was previously assumed, and more generally, are likely underappreciated winter predators in southern pine ecosystems. [ABSTRACT FROM AUTHOR]

The American Kestrel (Falco sparverius) is a small raptor that may be attracted to agroecosystems during both breeding and wintering seasons. In North America, American Kestrels from northern areas may migrate southward and overwinter in southern territories, co-occurring with resident kestrels in agroecosystems of Baja California, Mexico. We captured 56 adults during autumn and winter (2018–2019 and 2019–2020) in the southern part of the peninsula, and we evaluated the prevalence of ectoparasites on these kestrels. We found ectoparasites on 23.2% of individuals: 14.2% had lice, 1.7% cimicid bugs, and 7.1% hippoboscids flies. Lice included Degeeriella carruthi, Colpocephalum subzerafae, and Laemobothrion sp. Cimicid bugs found on one male were identified as Hesperocimex sp., a cimicid often recorded on birds that nest in cavities of the giant cardón cactus (Pachycereus pringlei). The prevalent louse fly was identified as the potentially pathogenic Icosta americana. All the parasites we recorded were the first records on American Kestrels in Mexico. [ABSTRACT FROM AUTHOR]

Background Mammalian target of rapamycin (mTOR) inhibitors suppress adrenal cortical carcinoma cell proliferation and cortisol production; the relationship between mTOR and aldosterone production has not been examined. Methods HAC15 cells were incubated with an mTOR activator and several inhibitors including AZD8055 (AZD) in the presence and absence of angiotensin II (AngII). The expression of rapamycin-sensitive adapter protein of mTOR (Raptor) and rapamycin-insensitive companion of mTOR (Rictor), adaptor proteins of mTOR complex 1 and 2, respectively, were studied in the HAC15 cells and deleted by CRISPR/gRNA. Results The mTOR inhibitors decreased aldosterone induced by AngII. Inhibition of mTOR by AZD significantly suppressed AngII-induced aldosterone and cortisol formation in a dose-dependent manner, whereas the mTOR activator MHY had no effect. AZD did not alter forskolin-induced aldosterone production showing that it is specific to the AngII signaling pathway. AngII-mediated ERK and mTOR activation were suppressed by AZD, along with a concomitant dose-dependent reduction of AngII-induced steroidogenic enzymes including steroidogenic acute regulatory protein, 3β-hydroxysteroid dehydrogenase-type 2, CYP17A1, and aldosterone synthase protein. Furthermore, mTOR components ribosomal protein S6 kinase (P70S6K) and protein kinase B phosphorylation levels were decreased by AZD. As mTOR exerts its main effects by forming complexes with adaptor proteins Raptor and Rictor, the roles of these individual complexes were studied. We found an increase in the phosphorylation of Raptor and Rictor by AngII and that their CRISPR/gRNA-mediated knockdown significantly attenuated AngII-induced aldosterone and cortisol production. Conclusion mTOR signaling has a critical role in transducing the AngII signal initiating aldosterone and cortisol synthesis in HAC15 cells and that inhibition of mTOR could be a therapeutic option for conditions associated with excessive renin–angiotensin system-mediated steroid synthesis. [ABSTRACT FROM AUTHOR]

Abstract Background Tauopathies, including Alzheimer’s disease, are characterized by the pathological aggregation of tau protein, which is strongly linked to dysregulation of the autophagy-lysosomal degradation pathway. However, therapeutic strategies targeting this pathway remain limited. Methods We used both in vitro and in vivo models to investigate the role of Raptor in tau pathology. Knockdown of Raptor was performed to assess its impact on mTORC1 activation, autophagy, and tau accumulation. The relationship between USP9X and Raptor was also examined. Pharmacological inhibition of USP9X with WP1130 was employed to further confirm the involvement of the USP9X-Raptor-mTORC1 axis in tau degradation. Results Elevated Raptor levels in the hippocampus of P301S mice led to hyperactivation of mTORC1, impairing autophagy flux. Knockdown of Raptor effectively suppressed mTORC1 activation, promoted autophagy, and mitigated the accumulation of tau and its phosphorylated isoforms. This reduction in tau pathology was accompanied by decreased neuronal loss in the hippocampus, amelioration of synaptic damage, and improvement in cognitive function. The increased Raptor protein observed in the hippocampus of P301S mice was likely attributable to elevated USP9X content, which enhanced Raptor deubiquitination and protected it from proteasomal degradation. Pharmacological inhibition of USP9X with WP1130 in vitro effectively suppressed Raptor, promoted autophagy, and accelerated the degradation of tau and phosphorylated tau. Conclusions Our findings highlight Raptor and USP9X as promising molecular targets for therapeutic intervention in tauopathies. Targeting the USP9X-Raptor-mTORC1 axis may provide a novel strategy for promoting autophagy and mitigating tau pathology in Alzheimer’s disease and other tauopathies. Graphical Abstract

Members of the genus Scaphanocephalus mature in accipitrids, particularly osprey, Pandion haliaetus, with metacercaria causing Black Spot Syndrome in reef fishes. In most of the world, only the type species, Scaphanocephalus expansus (Creplin, 1842) has been reported. Recent molecular studies in the Western Atlantic, Mediterranean and Persian Gulf reveal multiple species of Scaphanocephalus, but have relied on 28S rDNA, mainly from metacercariae, which limits both morphological identification and resolution of closely related species. Here we combine nuclear rDNA with mitochondrial sequences from adult worms collected in osprey across North America and the Caribbean to describe species and elucidate life cycles in Scaphanocephalus. A new species described herein can be distinguished from S. expansus based on overall body shape and size. Phylogenetic analysis of the whole mitochondrial genome of Scaphanocephalus indicates a close relationship with Cryptocotyle. We conclude that at least 3 species of Scaphanocephalus are present in the Americas and 2 others are in the Old World. Specimens in the Americas have similar or identical 28S to those in the Mediterranean and Persian Gulf, but amphi-Atlantic species are unlikely in light of divergence in cytochrome c oxidase I and the lack of amphi-Atlantic avian and fish hosts. Our results provide insight into the geographic distribution and taxonomy of a little-studied trematode recently linked to an emerging pathology in ecologically important reef fishes.

Migratory connectivity describes the linkage between breeding and nonbreeding sites, having major ecological implications in birds: 1 season influence the success of an individual or a population in the following season. Most studies on migratory connectivity have used large-scale approaches, often considering regional populations, but fine-scale studies are also necessary to understand colony connectivity. The lesser kestrel Falco naumanni , an insectivorous migratory raptor which form colonies during the breeding period, was considered to have strong connectivity based on regional populations. However, no small-scale studies on migratory connectivity have been conducted. Therefore, we GPS (Global Positioning System)-tracked 40 adult lesser kestrels from 15 different Spanish breeding colonies, estimating the overlap index between home ranges and the distance between their centroids. It was found that lesser kestrels from the same breeding colony placed their nonbreeding areas at 347 ± 281 km (mean ± standard deviation) away from each other (range = 23–990), and their home ranges overlapped by 38.4 ± 23.6%. No differences between intra-colony and inter-colony metrics were found, which suggests that lesser kestrels from the same breeding cluster do not overwinter together, but they spread out and mixed independently of the colony belonging throughout the nonbreeding range of the species. Ultimately, this study highlights the importance of performing connectivity studies using fine-scale approaches. [ABSTRACT FROM AUTHOR]

Aims Proper arteriogenesis after tissue ischaemia is necessary to rebuild stable blood circulation; nevertheless, this process is impaired in type 2 diabetes mellitus (T2DM). Raptor is a scaffold protein and a component of mammalian target of rapamycin complex 1 (mTORC1). However, the role of the endothelial Raptor in arteriogenesis under the conditions of T2DM remains unknown. This study investigated the role of endothelial Raptor in ischaemia-induced arteriogenesis during T2DM. Methods and results Although endothelial mTORC1 is hyperactive in T2DM, we observed a marked reduction in the expression of endothelial Raptor in two mouse models and in human vessels. Inducible endothelial-specific Raptor knockout severely exacerbated impaired hindlimb perfusion and arteriogenesis after hindlimb ischaemic injury in 12-week high-fat diet fed mice. Additionally, we found that Raptor deficiency dampened vascular endothelial growth factor receptor 2 (VEGFR2) signalling in endothelial cells (ECs) and inhibited VEGF-induced cell migration and tube formation in a PTP1B-dependent manner. Furthermore, mass spectrometry analysis indicated that Raptor interacts with neuropilin 1 (NRP1), the co-receptor of VEGFR2, and mediates VEGFR2 trafficking by facilitating the interaction between NRP1 and Synectin. Finally, we found that EC-specific overexpression of the Raptor mutant (loss of mTOR binding) reversed impaired hindlimb perfusion and arteriogenesis induced by endothelial Raptor knockout in high-fat diet fed mice. Conclusion Collectively, our study demonstrated the crucial role of endothelial Raptor in promoting ischaemia-induced arteriogenesis in T2DM by mediating VEGFR2 signalling. Thus, endothelial Raptor is a novel therapeutic target for promoting arteriogenesis and ameliorating perfusion in T2DM. [ABSTRACT FROM AUTHOR]

At the top of many ecosystems, raptors, also known as birds of prey, hold major influence. They shape their surroundings through their powerful hunting skills and complex interactions with their environment. This study investigates the beak morphology of four prominent raptor species, Golden eagle (Aquila chrysaetos), Common buzzard (Buteo buteo), Peregrine falcon (Falco peregrinus) and Common kestrel (Falco tinnunculus), found in Türkiye. By employing geometric morphometric methods, we investigate shape variations in the beaks of these species to unravel the adaptive significance of their cranial structures. This analysis reveals distinct beak morphologies among the studied raptors, reflecting adaptations to their feeding habits, hunting techniques and ecological niches. The results from Principal component analysis and Canonical variate analysis demonstrate significant differences in beak morphology between the Falconiformes and Accipitriformes clades, as well as among all three groups. The overall mean beak shapes of Golden Eagles are quite similar to Common Buzzards, with both species having longer beaks. In contrast, Falcons exhibit a distinctly different beak morphology, characterized by wider and shorter beaks. Changes in beak shape can lead to changes depending on the skull. It is thought that skull shape variations among predator families may have an impact on beak shape. These findings highlight the importance of integrating morphometric analyses with ecological insights to enhance our understanding of the evolutionary processes shaping raptor beak morphology. [ABSTRACT FROM AUTHOR]

Objective: The mechanistic target of rapamycin (mTOR) pathway has been implicated in promoting epileptogenesis in animal models of acquired epilepsy, such as posttraumatic epilepsy (PTE) following traumatic brain injury (TBI). However, the specific anatomical regions and neuronal populations mediating mTOR's role in epileptogenesis are not well defined. In this study, we tested the hypothesis that mTOR activation in dentate gyrus granule cells promotes neuronal death, mossy fiber sprouting, and PTE in the controlled cortical impact (CCI) model of TBI. Methods: An adeno‐associated virus (AAV)‐Cre viral vector was injected into the hippocampus of Rptorflox/flox (regulatory‐associated protein of mTOR) mutant mice to inhibit mTOR activation in dentate gyrus granule cells. Four weeks after AAV‐Cre or AAV‐vehicle injection, mice underwent CCI injury and were subsequently assessed for mTOR pathway activation by Western blotting, neuronal death, and mossy fiber sprouting by immunopathological analysis, and posttraumatic seizures by video‐electroencephalographic monitoring. Results: AAV‐Cre injection primarily affected the dentate gyrus and inhibited hippocampal mTOR activation following CCI injury. AAV‐Cre‐injected mice had reduced neuronal death in dentate gyrus detected by Fluoro‐Jade B staining and decreased mossy fiber sprouting by ZnT3 immunostaining. Finally, AAV‐Cre‐injected mice exhibited a decrease in incidence of PTE. Significance: mTOR pathway activation in dentate gyrus granule cells may at least partly mediate pathological abnormalities and epileptogenesis in models of TBI and PTE. Targeted modulation of mTOR activity in this hippocampal network may represent a focused therapeutic approach for antiepileptogenesis and prevention of PTE. [ABSTRACT FROM AUTHOR]

This article explores the nesting behavior of the Chimango Caracara, a medium-sized raptor, in urban areas of Argentina. While urban environments can provide resources for birds, they also pose risks such as pollution and collisions. The study documents four recorded nests in major cities, highlighting the adaptability of the Chimango Caracara's nesting habits. This is the first case of successful nesting on a human structure within a highly populated city. The article suggests that further research is needed on the presence of chimango pairs nesting in urban areas and the occurrence of colonial nesting in cities. [Extracted from the article]

Acoustic communication, such as bird song, is vital in animal ecology, facilitating reproduction, feeding, defense, and more. Variation in bird song may result from adaptation to environmental features such as anthropogenic noise. The vocal repertoire of raptors is essentially unstudied, particularly in urban environments. The aim of this work was to describe and quantify the acoustic repertoire of Chimango Caracaras (Milvago chimango) in rural and urban areas in La Pampa Province, Argentina. I recorded 26 1-min sound samples at each of four breeding colonies (one rural and three urban) during the austral reproductive season of 2021–2022. I recorded 241 vocalizations corresponding to nine clearly distinct call types. Two types of calls made up 50.6% and 19.5% of the vocalizations and seven others made up <10.0% each. Three call types had trills (fast repetitive notes). Average percentage of call types differed significantly between the two habitats (P < 0.01), with more trills produced in rural habitats. Average calling rate was 6.6 ± 5.1 calls/min at rural colonies and 10.7 ± 10.7 at urban colonies. The number of different call types produced was 2.1 ± 1.6 types/min at rural colonies and 2.7 ± 1.8 at urban colonies. The greater calling rate of Chimango Caracaras in urban areas may represent an attempt to improve signal effectiveness among the anthropogenic acoustic clutter. La comunicación acústica, como el canto de las aves, es vital en la ecología animal, al facilitar la reproducción, alimentación, defensa y otras actividades. La variación en el canto de las aves puede deberse a la adaptación a características ambientales como el ruido antropogénico. El repertorio vocal de las rapaces ha sido poco estudiado, especialmente en entornos urbanos. El objetivo de este trabajo fue describir y cuantificar el repertorio acústico de Milvago chimango en áreas rurales y urbanas en la provincia de La Pampa, Argentina. Registré 26 muestras de sonido de 1 minuto de duración cada una provenientes de cuatro colonias reproductivas (una rural y tres urbanas) durante la temporada reproductora austral de 2021–2022. Registré 241 vocalizaciones correspondientes a nueve tipos de llamadas claramente distintas. Dos tipos de llamadas representaron el 50.6% y el 19.5% de las vocalizaciones y otras siete representaron <10.0% cada una. Tres tipos de llamadas tuvieron trinos (notas rápidas y repetitivas). Los porcentajes de tipos de llamadas difirieron significativamente entre los dos hábitats (P<0.01), con más trinos producidos en hábitats rurales. La tasa de llamadas fue de 6.6 ± 5.1 llamadas/minuto en colonias rurales y 10.7 ± 10.7 en colonias urbanas. El número de tipos de llamadas diferentes producidas fue de 2.1 ± 1.6 tipos/minuto en colonias rurales y 2.7 ± 1.8 en colonias urbanas. La mayor tasa de llamadas de M. chimango en áreas urbanas puede representar un intento de mejorar la efectividad de la señal ante la distorsión acústica antropogénica. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Abstract Understanding how human activities affect wildlife is fundamental for global biodiversity conservation. Ongoing land use change and human‐induced climate change, compel species to adapt their behaviour in response to shifts in their natural environments. Such responses include changes to a species' diet or trophic ecology, with implications for the wider ecosystem. This is particularly the case for predatory species or those that occupy high positions within trophic webs, such as raptors. Between 2002 and 2019, we observed 1578 feeding events of the globally near threatened and understudied, Red‐necked Falcon (Falco chicquera) in Bangladesh. We explored the effects of mean monthly temperature, precipitation, temperature differences, and urban land cover on (a) mean prey weights and (b) dietary composition of 15 falcon pairs. Falcons hunted smaller prey items during months with increased temperatures and precipitation, and in more urban areas. However, during months with increased temperature differences, falcons tended to prey on larger prey items. Being specialist aerial hunters, these dietary patterns were largely driven by the probabilities of bats and birds in the diet. Falcons were more likely to prey on bats during warmer and wetter months. Furthermore, urban pairs tended to prey on bats, whereas more rural pairs tended to prey on birds. Mean monthly temperature difference, i.e., a proxy for climate change, was better at explaining the probability of bats in the falcon diet than mean monthly temperature alone. Anthropogenic dietary shifts can have deleterious effects on species with declining populations or those of conservation concern. The effects of urbanisation and human‐induced climate change are expected to continue into the foreseeable future. Therefore, our findings represent a cornerstone in our understanding of how falcons respond to an increasingly human‐dominated world.

Raptors can change the shape and area of their wings to an exceptional degree in a fast and efficient manner, surpassing other birds, insects, or bats. Some researchers have focused on the functional properties of muscle skeletons, mechanics, and flapping robot design. However, the wing motion of the birds of prey has not been measured quantitatively, and synthetic bionic wings with morphing abilities similar to raptors are far from reality. Therefore, in the current study, a 3D suspension system for holding bird carcasses was designed and fabricated to fasten the wings of Falco Peregrinus with a series of morphing postures. Subsequently, the wing skeleton of the falcon was scanned during extending motions using the computed tomography (CT) approach to obtain three consecutive poses. Subsequently, the skeleton was reconstructed to identify the contribution of the forelimb bones to the extending/folding motions. Inspired by these findings, we propose a simple mechanical model with four bones to form a wing-morphing mechanism using the proposed pose optimisation method. Finally, a bionic wing mechanism was implemented to imitate the motion of the falcon wing—divided into inner and outer wings with folding and twisting motions. The results show that the proposed four-bar mechanism can track bone motion paths with high fidelity.

BACKGROUND: The mTOR (mechanistic target of rapamycin) is an essential regulator of fundamental biological processes. mTOR forms 2 distinct complexes, mTORC1 (mTOR complex 1) when it binds with RAPTOR (Regulatory-associated Protein of mTOR) and mTORC2 (mTOR complex 2) when it associates with RICTOR (Rapamycin-insesitive companion of mTOR). Due to the previous link between the mTOR pathway, aldosterone, and blood pressure (BP), we anticipated that variants in the mTOR complex might be associated with salt-sensitive BP. METHODS: BP and other parameters were assessed after a one-week liberal Na+ (200 mmol/d) and a one-week restricted Na+ (10 mmol/d) diet in 608 White subjects from the Hypertensive Pathotype cohort, single-nucleotide variants in MTOR , RPTOR , and RICTOR genes were obtained for candidate genes analyses. RESULTS: The analysis revealed a significant association between a single nucleotide variants within the RPTOR gene and BP. Individuals carrying the RPTOR rs9901846 homozygous risk allele (AA) and heterozygous risk allele (GA) exhibited a 5 mm Hg increase in systolic BP on a liberal diet compared with nonrisk allele individuals (GG), but only in women. This single nucleotide variants effect was more pronounced on the restricted diet and present in both sexes, with AA carriers having a 9 mm Hg increase and GA carriers having a 5 mm Hg increase in systolic BP compared with GG. Interestingly, there were no significant associations between MTOR or RICTOR gene variants and BP. CONCLUSIONS: The RPTOR gene variation is associated with elevated BP in White participants, regardless of salt intake, specifically in females. [ABSTRACT FROM AUTHOR]

Ataxin‐2 (Atx2) is a polyglutamine (polyQ) protein, in which abnormal expansion of the polyQ tract can trigger protein aggregation and consequently cause spinocerebellar ataxia type 2 (SCA2), but the mechanism underlying how Atx2 aggregation leads to proteinopathy remains elusive. Here, we investigate the molecular mechanism and cellular consequences of Atx2 aggregation by molecular cell biology approaches. We have revealed that either normal or polyQ‐expanded Atx2 can sequester Raptor, a component of mammalian target of rapamycin complex 1 (mTORC1), into aggregates based on their specific interaction. Further research indicates that the polyQ tract and the N‐terminal region (residues 1–784) of Atx2 are responsible for the specific sequestration. Moreover, this sequestration leads to suppression of the mTORC1 activity as represented by down‐regulation of phosphorylated P70S6K, which can be reversed by overexpression of Raptor. As mTORC1 is a key regulator of autophagy, Atx2 aggregation and sequestration also induces autophagy by upregulating LC3‐II and reducing phosphorylated ULK1 levels. This study proposes that Atx2 sequesters Raptor into aggregates, thereby impairing cellular mTORC1 signaling and inducing autophagy, and will be beneficial for a better understanding of the pathogenesis of SCA2 and other polyQ diseases. [ABSTRACT FROM AUTHOR]

Purpose: Blunt bowel and/or mesenteric injury requiring surgery presents a diagnostic challenge. Although computed tomography (CT) imaging is standard following blunt trauma, findings can be nonspecific. Most studies have focused on the diagnostic value of CT findings in identifying significant bowel and/or mesenteric injury (sBMI). Some studies have described scoring systems to assist with diagnosis. Little attention, has been given to radiologist interpretation of CT scans. This study compared the discriminative ability of scoring systems (BIPS and RAPTOR) with radiologist interpretation in identifying sBMI. Methods: We conducted a retrospective chart review of trauma patients with suspected sBMI. CT images were reviewed in a blinded fashion to calculate BIPS and RAPTOR scores. Sensitivity and specificity were compared between BIPS, RAPTOR, and the admission CT report with respect to identifying sBMI. Results: One hundred sixty-two patients were identified, 72 (44%) underwent laparotomy and 43 (26.5%) had sBMI. Sensitivity and specificity were: BIPS 49% and 87%, AUC 0.75 (0.67–0.81), P < 0.001; RAPTOR 46% and 82%, AUC 0.72 (0.64–0.79), P < 0.001; radiologist impression 81% and 71%, AUC 0.82(0.75–0.87), P < 0.001. The discriminative ability of the radiologist impression was higher than RAPTOR (P = 0.04) but not BIPS (P = 0.13). There was not a difference between RAPTOR vs. BIPS (P = 0.55). Conclusion: Radiologist interpretation of the admission CT scan was discriminative of sBMI. Although surgical vigilance, including evaluation of the CT images and patient, remains fundamental to early diagnosis, the radiologist's impression of the CT scan can be used in clinical practice to simplify the approach to patients with abdominal trauma. [ABSTRACT FROM AUTHOR]

GPS satellite tracking allows novel investigations of how golden eagles Aquila chrysaetos use the landscape at several scales and at different life history stages, including research on geographical barriers which may prevent or limit range expansion or create population/sub-population isolation. If there are significant barriers to golden eagle movements, there could be demographic and genetic consequences. Genetic studies have led investigations on the identification of sub-species, populations, and sub-populations but should be conjoined with demographic studies and dispersal movements to understand fully such designations and their geographic delimitation. Scottish eagles are genetically differentiated from continental European birds, with thousands of years of separation creating a distinct population, though without sub-species assignation. They present unique research opportunities to examine barriers to movements illustrated by satellite tracking under Scotland's highly variable geography. We primarily examined two features, using more than seven million dispersal records from satellite tags fitted to 152 nestlings. The first was the presence of unsuitable terrestrial habitat. We found few movements across a region of largely unsuitable lowland habitat between upland regions substantially generated by geological features over 70 km apart (Highland Boundary Fault and Southern Uplands Fault). This was expected from the Golden Eagle Topography model, and presumed isolation was the premise for an ongoing reinforcement project in the south of Scotland, translocating eagles from the north (South Scotland Golden Eagle Project: SSGEP). Second was that larger expanses of water can be a barrier. We found that, for a northwestern archipelago (Outer Hebrides), isolated by ≥24 km of sea (and with prior assignation of genetical and historical separation), there were no tagged bird movements with the Inner Hebrides and/or the Highlands mainland (the main sub-population), confirming their characterisation as a second sub-population. Results on the willingness of eagles to cross open sea or sea lochs (fjords) elsewhere in Scotland were consistent on distance. While apparently weaker than the Outer Hebrides in terms of separation, the designation of a third sub-population in the south of Scotland seems appropriate. Our results validate the SSGEP, as we also observed no movement of birds across closer sea crossings from abundant Highland sources to the Southern Uplands. Based on telemetric results, we also identified where any re-colonisation of England, due to the SSGEP, is most likely to occur. We emphasise, nevertheless, that our study's records during dispersal will be greater than the natal dispersal distances (NDDs), when birds settle to breed after dispersal, and NDDs are the better shorter arbiter for connectivity. [ABSTRACT FROM AUTHOR]

The arrival‐time hypothesis of partial seasonal migration proposes that over‐winter residence is driven by reproductive benefits of early presence on the breeding grounds. Thus, it predicts increased occurrence of residence at reproductive age. In contrast, the body size hypothesis proposes age‐independent benefits of residence for large individuals, who should exhibit greater winter tolerance. Despite different expectations in age patterns for the two hypotheses in long‐lived partially migrant species, there is little empirical work investigating the ontogeny of migratory phenotypic expression, that is the expression of residence or migration.We investigated the influence of age, sex and body size on migratory phenotype throughout ontogeny (from first year to early adulthood) in a long‐lived partially migrant species, the red kite Milvus milvus. We GPS‐tracked 311 individuals tagged as juveniles and 70 individuals tagged as adults over multiple years, yielding 881 observed annual cycles. From this data, we estimated age‐dependent probabilities of the transition to residence and of survival in migrants and residents using a Bayesian multistate capture‐recapture model, as well as the probability of resuming migration once resident. We then calculated the resulting proportion of residents per age class.In both sexes, almost all juveniles migrated in their first winter, after which the probability of becoming resident gradually increased with age class to approximately 0.3 in adults (>3 calendar years). A size effect in third calendar year females suggests that large females adopt residence earlier in life than small females. The transition from residence back to migration only occurred with a probability of 0.15 across all resident individuals. In addition, survival was notably reduced in adult male migrants compared to adult male residents. These results are largely consistent with the arrival‐time and body size hypotheses, simultaneously.Our results reveal a plastic, yet primarily directional within‐individual change in migratory phenotype towards more residence with increasing age, varying between sexes and between individuals of different size. This study highlights that different individual characteristics can jointly shape the ontogeny of migratory behaviour and result in complex within‐population patterns and persistence of migratory phenotypes. [ABSTRACT FROM AUTHOR]

The mineralocorticoid receptor (MR) is a transcription factor for genes mediating diverse, cell-specific functions, including trophic effects as well as promoting fluid/electrolyte homeostasis. It was reported that in intercalated cells, phosphorylation of the MR at serine 843 (S843) by Unc-51–like kinase (ULK1) inhibits MR activation and that phosphorylation of ULK1 by mechanistic target of rapamycin (mTOR) inactivates ULK1, and thereby prevents MR inactivation. We extended these findings with studies in M1 mouse cortical collecting duct cells stably expressing the rat MR and a reporter gene. Pharmacological inhibition of ULK1 dose-dependently increased ligand-induced MR transactivation, while ULK1 activation had no effect. Pharmacological inhibition of mTOR and CRISPR/gRNA gene knockdown of rapamycin-sensitive adapter protein of mTOR (Raptor) or rapamycin-insensitive companion of mTOR (Rictor) decreased phosphorylated ULK1 and ligand-induced activation of the MR reporter gene, as well as transcription of endogenous MR-target genes. As predicted, ULK1 inhibition had no effect on aldosterone-mediated transcription in M1 cells with the mutated MR-S843A (alanine cannot be phosphorylated). In contrast, mTOR inhibition dose-dependently decreased transcription in the MR-S843A cells, though not as completely as in cells with the wild-type MR-S843. mTOR, Raptor, and Rictor coprecipitated with the MR and addition of aldosterone increased their phosphorylated, active state. These results suggest that mTOR significantly regulates MR activity in at least 2 ways: by suppressing MR inactivation by ULK1, and by a yet ill-defined mechanism that involves direct association with MR. They also provide new insights into the diverse functions of ULK1 and mTOR, 2 key enzymes that monitor the cell's energy status. [ABSTRACT FROM AUTHOR]

Caterpillars of Tineidae moths mainly feed on keratin sources and require moisture and warm temperature for emergence. The presence of Tineidae moth caterpillars, pupae, and adults in regurgitated pellets of harriers, diurnal migratory raptors wintering in India, suggests a potential dietary association and highlights the importance of considering associated organisms in raptor diet estimation studies. The caterpillars preferred rodent hairs present in the pellets over feather and arthropod remains. This is the first record of Tineidae moths on the pellets of harriers. [ABSTRACT FROM AUTHOR]

Constructing nests costs birds time and energy and may influence breeding success and productivity. The precise nature and extent of these costs is understudied, particularly among raptor species. We used linear and generalized linear mixed models to examine the time and reproductive costs of nest construction to Bald Eagles (Haliaeetus leucocephalus) in New Jersey, USA, from 2009 to 2021. To differentiate nest construction costs from the influence of experience, we separately analyzed the breeding performance and phenology of new pairs constructing nests, established pairs constructing nests, and established pairs reusing nests. We also considered the influence of weather, year, and ecoregion. New territorial pairs building nests were generally less successful and productive than established pairs building or reusing nests. However, these trends were largely attributable to a greater egg-laying rate among established pairs. Nest building pairs, new and established, were generally delayed in egg laying, hatching, and nestling fledging compared to established pairs reusing nests; new pairs were notably more delayed than established pairs building nests. Territorial pairs in the Atlantic Coastal Pine Barrens were less successful and productive than pairs in other ecoregions. Higher precipitation around the egg laying period was predictive of lower nest success and productivity rates but did not appear to affect phenology. Higher temperatures around this period also lowered these rates, with the further effect of advancing phenology. In New Jersey, climate change appears to be advancing breeding phenology and could constrain productivity by century's end, though we anticipate that density dependence will regulate and lower Bald Eagle breeding performance prior to this period. Breeding success and productivity rates, as well as the effects of year in our models, indicate that New Jersey's breeding Bald Eagle population is still healthy and growing. Overall, our results indicate that nest construction imposes minor temporal costs on Bald Eagles but does not meaningfully affect their breeding success or productivity, which may help inform management of Bald Eagle nests and populations. La construcción de nidos tiene un costo de tiempo y energía para las aves, y puede influir en el éxito reproductivo y la productividad. La naturaleza precisa y el alcance de estos costos están insuficientemente estudiados, especialmente entre las especies de aves rapaces. Utilizamos modelos lineales y modelos lineales mixtos generalizados para examinar los costos temporales y reproductivos de la construcción de nidos para Haliaeetus leucocephalus en Nueva Jersey, EEUU, desde 2009 hasta 2021. Para diferenciar los costos de construcción de nidos de la influencia de la experiencia en su construcción, analizamos por separado el resultado de la reproducción y la fenología en parejas nuevas que construían nidos, en parejas establecidas que construían nidos y en parejas establecidas que reutilizaban nidos. También consideramos la influencia del clima, el año y la ecorregión. Las parejas reproductoras nuevas que construían nidos fueron generalmente menos exitosas y productivas que las parejas establecidas que construían o reutilizaban nidos. Sin embargo, estas tendencias se debieron en gran medida a una mayor tasa de puesta de huevos entre las parejas establecidas. Las parejas nuevas y establecidas que construían nidos generalmente se retrasaron en la puesta de huevos, la eclosión y el emplumamiento de los volantones en comparación con las parejas establecidas que reutilizaban nidos; las parejas nuevas tuvieron un retraso notablemente mayor que las parejas establecidas que construían nidos. Las parejas reproductoras en los Bosques Costeros de Pino del Atlántico fueron menos exitosas y productivas que las parejas en otras ecorregiones. Una mayor precipitación alrededor del período de puesta de huevos predijo tasas de éxito y de productividad de los nidos más bajas, pero no pareció afectar la fenología. Temperaturas más altas alrededor de este período también redujeron estas tasas, con el efecto adicional de adelantar la fenología. En Nueva Jersey, el cambio climático parece estar adelantando la fenología de reproducción y podría limitar la productividad para finales del siglo, aunque anticipamos que la denso-dependencia regulará y disminuirá el resultado de la reproducción de H. leucocephalus antes de este período. En nuestros modelos, las tasas de éxito reproductivo y de productividad, así como los efectos del año, indican que la población reproductora de H. leucocephalus de Nueva Jersey sigue siendo saludable y está creciendo. En general, nuestros resultados indican que la construcción de nidos impone costos temporales menores a H. leucocephalus, pero no afecta significativamente su éxito reproductivo o productividad, lo que podría ayudar a la gestión de los nidos y de las poblaciones de esta especie. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Abstract Background Natal dispersal, the distance between site of birth and site of first breeding, has a fundamental role in population dynamics and species’ responses to environmental changes. Population density is considered a key driver of natal dispersal. However, few studies have been able to examine densities at both the natal and the settlement site, which is critical for understanding the role of density in dispersal. Additionally, the role of density on natal dispersal remains poorly understood in long-lived and slowly reproducing species, due to their prolonged dispersal periods and often elusive nature. We studied the natal dispersal of the white-tailed eagle (Haliaeetus albicilla) in response to local breeder densities. We investigated the effects of the number of active territories around the natal site on (a) natal dispersal distance and (b) the difference between natal and settlement site breeder density. We were interested in whether eagles showed tendencies of conspecific attraction (positive density-dependence) or intraspecific competition (negative density-dependence) and how this related to settlement site breeder density. Methods We used a combination of long-term visual and genotypic identification to match individuals from their breeding site to their natal nest. We identified natal dispersal events for 355 individuals hatched between 1984 and 2015 in the Baltic Sea coast and Arctic areas of Finland. Of those, 251 were identified by their genotype. Results Individuals born in high-density areas dispersed shorter distances than those born in low-density areas, but settled at lower density breeding sites in comparison to their natal site. Eagles born in low natal area densities dispersed farther but settled in higher density breeding sites compared to their natal site. Conclusions We show that eagles might be attracted by conspecifics (positive density-dependence) to identify high-quality habitats or find mates, but do not settle in the most densely populated areas. This indicates that natal dispersal is affected by an interplay of conspecific attraction and intraspecific competition, which has implications for population dynamics of white-tailed eagles, but also other top predators. Furthermore, our study demonstrates the value of long-term collection of both nestling and (non-invasive) adult DNA samples, and thereafter using genotype matching to identify individuals in long-lived and elusive species.

Background: Natal dispersal, the distance between site of birth and site of first breeding, has a fundamental role in population dynamics and species' responses to environmental changes. Population density is considered a key driver of natal dispersal. However, few studies have been able to examine densities at both the natal and the settlement site, which is critical for understanding the role of density in dispersal. Additionally, the role of density on natal dispersal remains poorly understood in long-lived and slowly reproducing species, due to their prolonged dispersal periods and often elusive nature. We studied the natal dispersal of the white-tailed eagle (Haliaeetus albicilla) in response to local breeder densities. We investigated the effects of the number of active territories around the natal site on (a) natal dispersal distance and (b) the difference between natal and settlement site breeder density. We were interested in whether eagles showed tendencies of conspecific attraction (positive density-dependence) or intraspecific competition (negative density-dependence) and how this related to settlement site breeder density. Methods: We used a combination of long-term visual and genotypic identification to match individuals from their breeding site to their natal nest. We identified natal dispersal events for 355 individuals hatched between 1984 and 2015 in the Baltic Sea coast and Arctic areas of Finland. Of those, 251 were identified by their genotype. Results: Individuals born in high-density areas dispersed shorter distances than those born in low-density areas, but settled at lower density breeding sites in comparison to their natal site. Eagles born in low natal area densities dispersed farther but settled in higher density breeding sites compared to their natal site. Conclusions: We show that eagles might be attracted by conspecifics (positive density-dependence) to identify high-quality habitats or find mates, but do not settle in the most densely populated areas. This indicates that natal dispersal is affected by an interplay of conspecific attraction and intraspecific competition, which has implications for population dynamics of white-tailed eagles, but also other top predators. Furthermore, our study demonstrates the value of long-term collection of both nestling and (non-invasive) adult DNA samples, and thereafter using genotype matching to identify individuals in long-lived and elusive species. [ABSTRACT FROM AUTHOR]

Early‐life experiences can drive subsequent variation in social behaviours, but how differences among individuals emerge remains unknown. We combined experimental manipulations with GPS‐tracking to investigate the pathways through which developmental conditions affect social network position during the early dispersal of wild red kites (Milvus milvus). Across 211 juveniles from 140 broods, last‐hatched chicks—the least competitive—had the fewest number of peer encounters after fledging. However, when food supplemented, they had more encounters than all others. Using 4425 bird‐days of GPS data, we revealed that this was driven by differential responses to competition, with less competitive individuals naturally spreading out into marginal areas, and clustering in central foraging areas when food supplemented. Our results suggest that early‐life adversities can cause significant natal legacies on individual behaviour beyond independence, with potentially far‐reaching consequences on the social and spatial structure of animal populations. [ABSTRACT FROM AUTHOR]

Wind power is commonly used to reduce greenhouse gas emissions but often has negative effects on biodiversity. In this study, I investigated the effects of wind farm and power line construction on the territory status of the Eurasian goshawk Accipiter gentilis, whether fledglings were produced or not, and the number of fledglings. Included were 55 goshawk territories investigated before and after the construction period. I found that the territory status declined significantly in the influence area within 3 km from the disturbance compared to the control area more than 7 km away. Interestingly, the decline in territory status was similar in the distance categories 0–1 km, 1–2 km, and 2–3 km, while there was nearly no change in territory status in the control area, thus indicating that the influence area from this kind of disturbance was minimum 3 km from the nest. The number of breeding pairs declined significantly during the construction period only in the influence area. Possible reasons might be higher mortality caused by collisions with power lines, desertion, avoidance of the areas with noise and disturbance from the constructions, and possible indirect effects caused by reductions in prey species. I found no effects of the construction on the number of fledglings. [ABSTRACT FROM AUTHOR]

Despite advancements through satellite telemetry, knowledge of the behaviour and ecology of large raptors during natal dispersal is still poor, even though this transience phase is important in understanding the population dynamics and conservation of these keystone species. After this phase, which can take several years, the subsequent rapid transitional event on first territory settlement is less studied. It apparently occurs earlier without competition from existing territory occupants. The time of year when young large raptors settle on a territory has rarely been addressed empirically. Our study of seasonal timing of first settlement used data from 46 golden eagles GPS-tagged as nestlings in Scotland which were tracked to their first territory settlement, as adjudged by a robust algorithmic method. We show that when young golden eagles occupied their first territory, their settlements were uncommon in summer and most common in late winter/spring, but also occurred in autumn into early winter. The significant seasonal pattern was consistent, regardless of the probable prior occupancy status (vacant/occupied) of the settled territory (respectively, the likely absence or presence of defending territorial birds). This showed that seasonal territory settlement was unlikely to be related to any response from territory occupants. It infers further that seasonality in first territory settlement was underpinned by innate behaviours in dispersing eagles. Seasonal distribution of settlement dates was significantly different between sexes, with males more likely to settle in autumn, predominantly in prior vacant territories. We speculate on potential causative drivers behind our results and conclude that more research is clearly needed in this field of study. [ABSTRACT FROM AUTHOR]

The hierarchical model of provisioning posits that parents employ a strategic, sequential use of three provisioning tactics as offspring demand increases (e.g. due to increasing brood size and age). Namely, increasing delivery rate (reducing intervals between provisioning visits), expanding provisioned diet breadth, and adopting variance-sensitive provisioning. We evaluated this model in an Arctic breeding population of Peregrine falcons (Falco peregrinus tundrius) by analyzing changes in inter-visit-intervals (IVIs) and residual variance in IVIs across 7 study years. Data were collected using motion-sensitive nest camera images and analyzed using Bayesian mixed effect models. We found strong support for a decrease in IVIs (i.e. increase in delivery rates) between provisioning visits and an increase in residual variance in IVIs with increasing nestling age, consistent with the notion that peregrines shift to variance-prone provisioning strategies with increasing nestling demand. However, support for predictions made based on the hierarchical model of tactics for coping with increased brood demand was equivocal as we did not find evidence in support of expected covariances between random effects (i.e. between IVI to an average sized brood (intercept), change in IVI with brood demand (slope) or variance in IVI). Overall, our study provides important biological insights into how parents cope with increased brood demand. [ABSTRACT FROM AUTHOR]

Understanding drivers underlying birds' responses to operational wind turbines is essential for robust wind farm proposal assessments, especially for large raptors with life history traits engendering sensitivity to impacts from two potential adverse effects: fatality through collision with rotating turbine blades and functional habitat loss through avoidance of turbines. The balance between these two potential effects represents opposing extremes on a continuum and is influenced by several factors. Collisions have an obvious impact on survival, but the impacts of avoidance may be more insidious and potentially more significant for a population. It is reasonable to conclude that collisions are less likely when blades are motionless. Consequently, turbine shutdown systems (TSSs, "shutdown on demand" or "curtailment"), instigated as raptors approach operational turbines, may provide mitigation against collisions. By contrast, if avoidance is most likely, this could be independent of blade motion, and TSSs/curtailment would provide no mitigation against habitat loss. For birds tending to wariness of turbines, therefore, it is important to understand if it is conditional on blade motion. Scottish golden eagles show a strong propensity to avoid (be wary of) turbines, subject largely to the suitability of habitat at and surrounding turbine locations. A previous Scottish study found that approach distances to turbines by non-territorial eagles were unaffected by blade motion but were closer at higher wind speed. Here, we analyse movement data from a GPS-tagged territorial eagle and non-territorial eagles responding to the motion status (and wind speed) of turbines at another Scottish wind farm. Eagles' approach distances to turbines were only weakly affected by blade motion but were closer at higher wind speed. We again found that habitat suitability in and around turbine locations was strongly influential on eagles' approach distance to turbines. Our confirmation that blade motion had little effect on Scottish golden eagles' wariness of turbines suggests that for eagles that are prone to avoid turbines, their wariness is a response to turbines per se, and not blades' movement. In our study system, and others where avoidance is the predominant response, curtailment of turbines' operation on birds' close approaches, or making turbine blades more obvious, should, therefore, have little material influence on functional habitat loss impacts. If true, this has important implications for wind farm designs and any proposed mitigation. [ABSTRACT FROM AUTHOR]

Food supply stands out as one of the most critical drivers of population demographics by limiting reproductive rates. In this study, we assessed fluctuations in diet composition and monitored various reproductive parameters over a nine-year period in a Golden Eagle population in an Eastern European peatland. The identification of 2439 prey specimens from 84 species revealed that the studied eagles primarily preyed upon birds (constituting 78.3% of prey numbers and 67.2% of prey biomass) and less on mammals (21.6% and 32.8%, respectively). Grouse emerged as the most important prey group (31% and 27%), followed by waterfowl (17%) and hares (8% and 14%). The most significant prey species, both in terms of numbers and weight, were the Black Grouse, Mountain Hare, Common Crane, and Capercaillie. The share of the Black Grouse decreased, while those of the White-fronted Goose, Roe Deer, and hares increased. The food niche, as measured by the Levins' index, was broad (6.6), and it expanded during the study. On average, 58.3% of Golden Eagle pairs initiated breeding annually, with 69.1% successfully completing it, and 0.41 young per occupied territory were produced annually; there was pronounced interannual variation in reproductive performance. These fluctuations were associated with the shares of White-fronted Goose, Capercaillie, Mountain Hare and Roe Deer in the diet, suggesting that these species may be gaining increasing importance for the Golden Eagle, particularly following the decline of the Black Grouse. [ABSTRACT FROM AUTHOR]

Natal dispersal distance (NDD) is critical in understanding and defining populations and their conservation. It is defined as the linear distance between the natal location and first reproductive ('effective NDD') or potential reproductive ('gross NDD') location. It is a measure of gene flow and the functional connectivity across generations between individuals breeding in the same or different geographies. NDD is difficult to record in large raptors. GPS‐satellite telemetry has facilitated its recording. Previous Scottish studies showed that gross and effective NDD were apparently equivalent, and an algorithm based on telemetric data could identify the territory settlement timing and location of birds originally tagged as nestlings. We analysed natal dispersal data from 39 Golden Eagles GPS‐tagged in Scotland to estimate NDD. Raw median estimates were 29.8 km for males (n = 22) and 58.6 km for females (n = 17), 38.1 km averaged across sexes. Males had significantly shorter NDD, as theoretically predicted. Our NDD estimates were shorter but not grossly dissimilar to those from the USA, where sex differences in NDD had not been confirmed. Respective sample sizes may underly the latter contrast in confirmation. We also showed that in the absence of data from sexed birds, NDD estimates can be different. Natal dispersal duration was not related to NDD, suggesting that time to prospect a territory opportunity was not associated with the selected territory's distance from the natal site. The previous status of the subsequent settled territory (occupied or vacant) was also not related to NDD. We conclude that sex differences in NDD are important in application to population demography and conservation. Although we found no support for two other potential drivers of NDD (natal dispersal duration and previous territory status), identifying additional influences on NDD is in its infancy in large raptors and deserves more study. [ABSTRACT FROM AUTHOR]

Like humans, chimpanzees (Pan troglodytes) are well known for their vertebrate and invertebrate hunting, but they rarely scavenge. In contrast, while hunting and meat consumption became increasingly important during the evolution of the genus Homo, scavenging meat and marrow from carcasses of large mammals was also likely to be an important component of their subsistence strategies. Here, we describe a confrontational scavenging interaction between an adult male chimpanzee from the Issa Valley and a crowned eagle (Stephanoaetus coronatus), which resulted in the chimpanzee capturing and consuming the carcass of a juvenile bushbuck (Tragelaphus scriptus). We describe the interaction and contextualize this with previous scavenging observations from chimpanzees. [ABSTRACT FROM AUTHOR]

In the midst of the sixth mass extinction, limited resources are forcing conservationists to prioritize which species and places will receive conservation action. Evolutionary distinctiveness measures the isolation of a species on its phylogenetic tree. Combining a species' evolutionary distinctiveness with its globally endangered status creates an EDGE score. We use EDGE scores to prioritize the places and species that should be managed to conserve bird evolutionary history. We analyzed all birds in all countries and important bird areas. We examined parrots, raptors, and seabirds in depth because these groups are especially threatened and relatively speciose. The three focal groups had greater median threatened evolutionary history than other taxa, making them important for conserving bird evolutionary history. Australia, Brazil, Indonesia, Madagascar, New Zealand, and the Philippines were especially critical countries for bird conservation because they had the most threatened evolutionary history for endemic birds and are important for parrots, raptors, and seabirds. Increased enforcement of international agreements for the conservation of parrots, raptors, and seabirds is needed because these agreements protect hundreds of millions of years of threatened bird evolutionary history. Decisive action is required to conserve the evolutionary history of birds into the Anthropocene. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a common malignant tumor with high mortality. Human phenylalanine tRNA synthetase (PheRS) comprises two α catalytic subunits encoded by the FARSA gene and two β regulatory subunits encoded by the FARSB gene. FARSB is a potential oncogene, but no experimental data show the relationship between FARSB and HCC progression. We found that the high expression of FARSB in liver cancer is closely related to patients' low survival and poor prognosis. In liver cancer cells, the mRNA and protein expression levels of FARSB are increased and promote cell proliferation and migration. Mechanistically, FARSB activates the mTOR complex 1 (mTORC1) signaling pathway by binding to the component Raptor of the mTORC1 complex to play a role in promoting cancer. In addition, we found that FARSB can inhibit erastin-induced ferroptosis by regulating the mTOR signaling pathway, which may be another mechanism by which FARSB promotes HCC progression. In summary, FARSB promotes HCC progression and is associated with the poor prognosis of patients. FARSB is expected to be a biomarker for early screening and treatment of HCC. [ABSTRACT FROM AUTHOR]

The range-wide recovery of Bald Eagles (Haliaeetus leucocephalus) is one of the great North American conservation successes, with the Bald Eagle population in Florida contributing substantially to this recovery. Florida has one of the densest concentrations of nesting Bald Eagles in the lower 48 states and sustained a population monitoring program that spanned 45 yr. We used nest monitoring data from 1972–2017 to quantify changes in the size, extent, and productivity of the breeding Bald Eagle population in Florida. We documented an increase in the number of occupied Bald Eagle territories from 88 in 1973 to an estimated 1565 in 2017, with nests recorded in 64 of Florida's 67 counties by the end of the monitoring efforts. Mean annual growth rate in the number of occupied eagle territories in Florida was 5.5 ± 1.1% (SE). High reproductive rates, exemplified by a mean productivity of 1.13 ± 0.02 fledglings per occupied nest, a mean brood size of 1.54 ± 0.01 fledglings per successful nest, and the production of nearly 40,000 fledglings over a 45-yr period, translated into substantial gains for the state and southeastern US Bald Eagle population. Eagles have established a large, spatially expansive, and productive breeding population in Florida, one that exceeded the conservation objectives established when the species was state-delisted in 2008. These data provided key insights into the breeding ecology, recovery, and long-term stability of Bald Eagles in Florida. Given the predicted increase in the human population and landscape modification anticipated in the coming years, the conservation of the eagle population within Florida will require adaptive management strategies. [ABSTRACT FROM AUTHOR]

Abstract Background mTORC1 (mechanistic target of rapamycin complex 1) is associated with lymphoma progression. Oncogenic RRAGC (Rag guanosine triphosphatase C) mutations identified in patients with follicular lymphoma facilitate the interaction between Raptor (regulatory protein associated with mTOR) and Rag GTPase. It promotes the activation of mTORC1 and accelerates lymphomagenesis. Cardamonin inhibits mTORC1 by decreasing the protein level of Raptor. In the present study, we investigated the inhibitory effect and possible mechanism of action of cardamonin in RRAGC-mutant lymphoma. This could provide a precise targeted therapy for lymphoma with RRAGC mutations. Methods Cell viability was measured using a cell counting kit-8 (CCK-8) assay. Protein expression and phosphorylation levels were determined using western blotting. The interactions of mTOR and Raptor with RagC were determined by co-immunoprecipitation. Cells overexpressing RagC wild-type (RagCWT) and RagC Thr90Asn (RagCT90N) were generated by lentiviral infection. Raptor knockdown was performed by lentivirus-mediated shRNA transduction. The in vivo anti-tumour effect of cardamonin was assessed in a xenograft model. Results Cardamonin disrupted mTOR complex interactions by decreasing Raptor protein levels. RagCT90N overexpression via lentiviral infection increased cell proliferation and mTORC1 activation. The viability and tumour growth rate of RagCT90N-mutant cells were more sensitive to cardamonin treatment than those of normal and RagCWT cells. Cardamonin also exhibited a stronger inhibitory effect on the phosphorylation of mTOR and p70 S6 kinase 1 in RagCT90N-mutant cells. Raptor knockdown abolishes the inhibitory effects of cardamonin on mTOR. An in vivo xenograft model demonstrated that the RagCT90N-mutant showed significantly higher sensitivity to cardamonin treatment. Conclusions Cardamonin exerts selective therapeutic effects on RagCT90N-mutant cells. Cardamonin can serve as a drug for individualised therapy for follicular lymphoma with RRAGC mutations.

Satellite tracking allows for novel investigations into golden eagle home range characteristics. Understanding home range characteristics is important for conservation and for assessing the potential impact of landscape changes from forest planting, wind farms, etc. Small sample sizes, inconsistent definitions and methods restricted several previous studies. Our study involved 69 resident tagged eagles with over one year of data across five Scottish regions. Home range size was estimated from 95% isopleth contours extracted from Utilisation Distributions. Above a small threshold, estimated range size was not affected by the number of records but at least one year of data is required, largely because of the breeding and non-breeding seasonal differences. There were no significant range size differences between birds tagged as range holders and those previously tagged as nestlings. Across four regions, with considerable intra-regional variation, planar 95% isopleths did not differ (medians, km2): Argyll 58.9, Northwest Highlands 61.7, Northeast Highlands 89.3, South of Scotland 91.9. Ranges in the isolated Outer Hebrides region were exceptionally small, at 24.0 km2. Estimated range area was usually reduced to 70–80% of the planar area when restricted to usable habitat, as estimated by the Golden Eagle Topography (GET) model. Applying measures of known unsuitable habitat (closed-canopy commercial forest and wind turbines) further reduced usable open land. Loss of otherwise suitable habitat was substantially due to commercial forest. Larger ranges had larger extents of suitable habitat (according to GET), with no apparent optimum of preferred GET habitat. Range size was not different across a year between the sexes. Breeding ranges were smaller, and females’ breeding ranges were much smaller than those of males, but larger than males’ ranges in the non-breeding season. Breeding attempt duration was probably also influential. Our study provides novel insights into golden eagle home range characteristics and can guide further research and practical applications.