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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]

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]

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 less likely to occur in open environments, 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]

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]

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]

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. [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]

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]

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]

Hypothalamic mTORC1 signaling is involved in nutrient sensing. Neurons that express the agouti-related protein (AgRP) are activated by food restriction and integrate interoceptive and exteroceptive signals to control food intake, energy expenditure, and other metabolic responses. To determine whether mTORC1 signaling in AgRP neurons is necessary for regulating energy and glucose homeostasis, especially in situations of negative energy balance, mice carrying ablation of the Raptor gene exclusively in AgRP-expressing cells were generated. AgRPΔRaptor mice showed no differences in body weight, fat mass, food intake, or energy expenditure; however, a slight improvement in glucose homeostasis was observed compared to the control group. When subjected to 5 days of food restriction (40% basal intake), AgRPΔRaptor female mice lost less lean body mass and showed a blunted reduction in energy expenditure, whereas AgRPΔRaptor male mice maintained a higher energy expenditure compared to control mice during the food restriction and 5 days of refeeding period. AgRPΔRaptor female mice did not exhibit the food restriction-induced increase in serum corticosterone levels. Finally, although hypothalamic fasting- or refeeding-induced Fos expression showed no differences between the groups, AgRPΔRaptor mice displayed increased hyperphagia during refeeding. Thus, some metabolic and neuroendocrine responses to food restriction are disturbed in AgRPΔRaptor mice. [ABSTRACT FROM AUTHOR]

Outdoor recreation has increased in recent decades, with an intensification after the COVID‐19 lockdown. Previous studies have shown that disturbances from this activity may affect species behaviour and fitness, but its effect on ecological processes has been overlooked. Here, we test the impact of outdoor recreation on terrestrial vertebrate scavenger assemblage and scavenging patterns in El Hondo Natural Park, a Mediterranean wetland located in south‐eastern Spain. We placed 185 carcasses monitored with camera traps between February 2020 and May 2021 in two areas: 'public access area', where visitors can freely access and carry out outdoor recreation, and 'restricted area', where visitors are not allowed. Our results showed that outdoor recreation altered the scavenger assemblage composition, especially affecting large species such as raptors. Non‐native species scavenged almost four times more often on carcasses in public access areas than in the restricted areas, showing that human activities promote the presence of non‐native species. Furthermore, vertebrates completely consumed 68.2% of the carcasses in the restricted area, decreasing to 46.7% in the public access area. In the restricted area, consumption time was shorter (111.8 vs. 157.5 h) and consumed biomass by vertebrate scavengers was larger (73.9 vs. 52.2%) than in public access area, evidencing that outdoor recreation also affects scavenging processes. Our study shows that outdoor recreation profoundly alters not only the scavenger assemblage but also key ecological processes such as carrion removal. This highlights the urgency of regulating tourism and maintaining restricted areas to preserve biodiversity and ecological processes, especially in highly anthropized landscapes. [ABSTRACT FROM AUTHOR]

The migratory behaviour of Ospreys (Pandion haliaetus) has been well studied using satellite telemetry, but studies on their behaviour in the breeding area are scarce. We caught and fitted 17 adult Ospreys with solar-powered GPS-enhanced satellite transmitters in northeast Germany and tracked them for up to 7 years. There was a high variation in home range size depending on sex, nesting site and breeding success. The home ranges of successfully breeding males (median 33.4 km2, 95% kernel density estimations) were significantly larger than those of females (median 4.6 km2) and varied in extent and shape between individuals. Some females made long excursions and sometimes spent the night at great distances to their nests after the juveniles had fledged but they also returned to the nesting area before they left for migration. The males' home range areas were consistent during the breeding period. The proportion of water surfaces on the home range areas of males ranged between 9.6 and 29%. The overnight roosts were found in distances up to 7.83 km (median 980 m) for successfully breeding males and up to 105 km (median 568 m) for successfully breeding females. The correlation between overnight roost-nest distance and the corresponding home range area was significant for females but not for males. The overlap in the home ranges of individual males that occupied the same nests in different years varied between 37.3 and 54.7% of the mutual home ranges. Males partly included the same waterbodies in their home ranges, but they also visited different lakes. In the incubation and nestling phases, females are closely bound to the nest, whereas their mates can range over vast areas. [ABSTRACT FROM AUTHOR]

A 21‐year‐old, suspected female captive ferruginous hawk (Buteo regalis) was followed for 3 years due to an iridial mass of the left eye (OS) that progressively increased in size. Enucleation of OS was eventually recommended due to the iridial mass taking up approximately 75% of the anterior chamber, and the bird seemed less active. A complete physical examination, complete blood cell count, biochemistry, and survey radiographs were performed pre‐surgery with no findings indicating metastasis. A subconjunctival enucleation was performed and the globe was submitted for histopathology through the Comparative Ocular Pathology Lab of Wisconsin. The histopathologic evaluation determined the mass to be consistent with an iris melanocytoma, which has not been previously reported in this species. The patient recovered well from surgery and has remained comfortable and active for 117 days post‐surgery. This case report aimed to review the current available information on avian ocular neoplasms as well as describe the clinical presentation, medical management and surgical procedure, and long‐term follow‐up for this patient to enhance clinical understanding of the behavior of iris melanocytic tumors in avian species. [ABSTRACT FROM AUTHOR]

Vocalization in birds serves an important role in territory establishment and mate attraction as well as maintaining conspecific interactions and providing signals pertaining to food or threat. In Malaysia, most raptor behavioral studies on vocalization have been carried out on nocturnal raptors. Such studies have often been limited by the difficulty of accessing habitats where forest species reside and by raptors' elusive behaviors. We assessed the vocalization and vocal activity patterns of a common diurnal raptor, the Changeable Hawk-Eagle (Nisaetus cirrhatus), in an isolated lowland forest reserve, the Ayer Hitam Forest Reserve in Selangor, Malaysia, in mid-April 2021. Automated bioacoustics recorders were placed for 5 d in four different sites to passively collect the hawk-eagles' vocalizations. We recorded 480 hr of calls over the 5 d and the Changeable Hawk-Eagle uttered at least seven call types, with peak and longer call events at midday (1100 H and 1200 H, respectively). Calls were heard from 30 min before sunrise (0600 H) until shortly after sunset (1900 H). Call type 1 was by far the most common call type (2738 calls over 5 d) and was uttered throughout the day, possibly during flight and when perched. Other call types were uttered from late morning (1000 H) with exception of call type 3, which was uttered earlier (0900 H). Our findings may help provide improved raptor survey methods as well as fill the knowledge gap for diurnal raptor vocalizations in Malaysia. La vocalización en las aves cumple un papel importante en el establecimiento del territorio, en la atracción de la pareja, en el mantenimiento de interacciones conespecíficas y en la emisión de señales relacionadas con comida o amenaza. En Malasia, la mayoría de los estudios de comportamiento de rapaces sobre vocalización se han llevado a cabo en rapaces nocturnas. Dichos estudios a menudo se han visto limitados por la dificultad de acceder a los hábitats donde residen las especies de bosque y por los comportamientos esquivos de las aves rapaces. Evaluamos la vocalización y los patrones de actividad vocal de una rapaz diurna común, Nisaetus cirrhatus, en una reserva forestal aislada de tierras bajas, la Reserva Forestal Ayer Hitam en Selangor, Malasia, a mediados de abril de 2021. Se colocaron grabadores bioacústicos automatizados durante cinco días en cuatro sitios diferentes para recolectar pasivamente las vocalizaciones de N. cirrhatus. Registramos 480 horas de llamadas durante los cinco días y N. cirrhatus emitió al menos siete tipos de llamadas, con un pico de llamadas y llamadas más largas al mediodía (1100 H y 1200 H, respectivamente). Las llamadas se escucharon desde 30 minutos antes del amanecer (0600 H) hasta poco después del atardecer (1900 H). El tipo 1 de llamada fue por mucho el más común (2738 llamadas durante cinco días) y se emitió durante todo el día, posiblemente durante el vuelo y cuando estaba posado. Otros tipos de llamadas se emitieron desde última hora de la mañana (1000 H), con excepción del tipo 3 de llamada, que se emitió antes (0900 H). Nuestros hallazgos pueden ayudar a proporcionar mejores métodos de estudio de aves rapaces, así como llenar el vacío de conocimiento sobre las vocalizaciones diurnas de aves rapaces en Malasia. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Background: In the context of rapid development of wind energy infrastructure, information on the flight height of birds is vital to assess their collision risk with wind turbines. GPS tags potentially represent a powerful tool to collect flight height data, yet GPS positions are associated with substantial vertical error. Here, we assessed to what extent high-frequency GPS tracking with fix intervals of 2–3 s (GPS remaining turned on between fixes), or barometric altimetry using air pressure loggers integrated in GPS tags, improved the accuracy of height data compared to standard low-frequency GPS tracking (fix interval ≥ 5 min; GPS turned off between fixes). Results: Using data from 10 GPS tag models from three manufacturers in a field setting (194 tags deployed on free-living raptors), we estimated vertical accuracy based on periods when the birds were stationary on the ground (true height above ground was approximately zero), and the difference between GPS and barometric height in flight. In GPS height data, vertical accuracy was mainly driven by noise (little bias), while in barometric data, it was mostly affected by bias (little noise). In high-frequency GPS data, vertical accuracy was improved compared to low-frequency data in each tag model (mean absolute error (AE) reduced by 72% on average; range of mean AE 2–7 vs. 7–30 m). In barometric data, vertical accuracy did not differ between high- and low-frequency modes, with a bias of − 15 to − 5 m and mean AE of 7–15 m in stationary positions. However, the median difference between GPS and barometric data was smaller in flight positions than in stationary positions, suggesting that the bias in barometric height data was smaller in flight. Finally, simulations showed that the remaining vertical error in barometric and high-frequency GPS data had little effect on flight height distributions and the proportion of positions within the collision risk height range, as opposed to the extensive noise found in low-frequency GPS data in some tag models. Conclusions: Barometric altimetry may provide more accurate height data than standard low-frequency GPS tracking, but it involves the risk of a systematic error. Currently, high-frequency GPS tracking provides highest vertical accuracy and may thus substantially advance the study of wind turbine collision risk in birds. [ABSTRACT FROM AUTHOR]

Research on potentially adverse effects of wind farms is an expanding field of study and often focuses on large raptors, such as golden eagles, largely because of their life history traits and extensive habitat requirements. These features render them sensitive to either fatality (collision with turbine blades) or functional habitat loss (avoidance through wariness of turbines). Simplistically, avoidance is antagonistic to collision; although, the two processes are not necessarily mutually exclusive in risk. A bird that does not enter a wind farm or avoids flying close to turbines cannot collide with a blade and be killed. In the USA, collision fatality is implicated as the typical adverse effect. In Scotland, avoidance of functional habitat loss appears more likely, but this depends in part on the habitat suitability of turbine locations. Previous Scottish studies have largely concentrated on the responses of GPS-tagged non-territorial golden eagles during dispersal. Several arguments predict that territorial eagles may have lower avoidance (be less wary) of turbines than non-territorial birds. Hence, we contrasted the responses of GPS-tagged non-territorial (intruding) and territorial eagles to the same turbines at 11 operational Scottish wind farms. We show that territorial eagles rarely approached turbines, but, as in previous Scottish studies of non-territorial birds, the spatial extent of avoidance depended on the habitat suitability of both turbine locations and their wider surroundings. Unexpectedly, we found that territorial eagles were apparently as wary as intruding non-territorial conspecifics of the same turbines. Our results show that regardless of age or territorial status, Scottish golden eagles largely avoided wind turbine locations, but this avoidance was conditional, in part, on where those turbines were located. Responses to turbines were also strongly dependent on birds' identities and different wind farms. We speculate on how widespread our findings of avoidance of turbines by golden eagles are elsewhere in Europe, where there appear to be no published studies showing the level of collision fatalities documented in the USA. [ABSTRACT FROM AUTHOR]

The mechanistic target of rapamycin (mTOR) kinase is a central regulator of cell growth and metabolism. It is the catalytic subunit of two distinct large protein complexes, mTOR complex 1 (mTORC1) and mTORC2. mTOR activity is subjected to tight regulation in response to external nutrition and growth factor stimulation. As an important mechanism of signaling transduction, the 'second messenger' cyclic nucleotides including cAMP and cGMP and their associated cyclic nucleotide-dependent kinases, including protein kinase A (PKA) and protein kinase G (PKG), play essential roles in mediating the intracellular action of a variety of hormones and neurotransmitters. They have also emerged as important regulators of mTOR signaling in various physiological and disease conditions. However, the mechanism by which cAMP and cGMP regulate mTOR activity is not completely understood. In this review, we will summarize the earlier work establishing the ability of cAMP to dampen mTORC1 activation in response to insulin and growth factors and then discuss our recent findings demonstrating the regulation of mTOR signaling by the PKA- and PKG-dependent signaling pathways. This signaling framework represents a new non-canonical regulation of mTOR activity that is independent of AKT and could be a novel mechanism underpinning the action of a variety of G protein-coupled receptors that are linked to the mTOR signaling network. We will further review the implications of these signaling events in the context of cardiometabolic disease, such as obesity, non-alcoholic fatty liver disease, and cardiac remodeling. The metabolic and cardiac phenotypes of mouse models with targeted deletion of Raptor and Rictor, the two essential components for mTORC1 and mTORC2, will be summarized and discussed. [ABSTRACT FROM AUTHOR]

Bird assemblages can be found in archeological sites throughout the Pleistocene. Taphonomy studies are key to understanding how such assemblages were formed. These assemblages can be generated by various agents, including human groups, animals, and natural death. In this paper, we analyzed the avifaunal assemblage from level TE9d at the Sima del Elefante site, where corvid (Corvidae) remains are the most abundant taxa, as reported in previous studies from that deposit. The remains of smaller birds (Charadriiformes, Rallidae) and large raptors (Aquila cf. heliaca/adalberti, Haliaeetus albicilla) have also been documented. Our taphonomic analysis shows that birds of prey were the main accumulators of bird remains at the site. The presence of modifications such as beak/talon marks and different degrees of digestion reinforce the idea that both diurnal and nocturnal raptors were involved. Nevertheless, we cannot rule out the accumulation by natural death of those species that could have nested in the rocky walls of the cave. The absence of evidence of anthropogenic activity on the bird remains from level TE9d therefore indicates that hominins were not involved in this accumulation. These results can be considered a new contribution to the discussion on the origin of avifaunal accumulations in Pleistocene archeological contexts. [ABSTRACT FROM AUTHOR]

Gut microbiota are increasingly recognized as important drivers of host health and fitness across vertebrate taxa. Given that gut microbial composition is directly influenced by the environment, gut microbiota may also serve as an eco‐physiological mechanism connecting host ecology, such as diet, and physiology. Although gut microbiota have been well‐studied in mammalian systems, little is known about how gut microbial diversity and composition impact morphological and physiological development in wild birds. Here, we characterized both diet and gut microbial diversity of free‐living American kestrel Falco sparverius nestlings throughout development to test whether gut microbial diversity predicts host morphological and physiological traits in either contemporary or time‐lagged manners. Gut microbial alpha diversity on day 21 of nestling development was positively correlated with diet alpha diversity representative of the majority of nestling development (days 5–20). Gut microbial alpha diversity early in development was negatively correlated with body mass in both contemporary and time‐lagged manners. Gut microbial alpha diversity early in development was positively correlated with blood glucose later in development. As nestlings experience rapid growth demands in preparation to fledge, these time‐lagged associations may indicate that gut microbial diversity at early critical developmental windows may determine the future trajectory of morphological and physiological traits underlying metabolism that ultimately impact fitness. [ABSTRACT FROM AUTHOR]

The post‐fledging dependence period (PFDP), which extends from a fledgling's first flight out of the nest to its departure from the parents' territory, is crucial in the lifecycle of birds. During this period, juveniles develop their flight and foraging skills to become fully independent. Despite the importance of this life stage in basic bird ecology and conservation, it remains largely overlooked – notably its link with the acquisition of flight skills. In this study, we modeled the variation in seven proxies describing flight skills of 84 GPS‐tracked golden eagle juveniles in France between 2016 and 2020. Juveniles had a long but highly variable PFDP, averaging 177.9 (± 62.2) days after departure from the nest. This period is divided into two phases: a first phase of rapid increase in flight skills over the first 60 days after departure from the nest, followed by a plateau in which flight skills no longer develop until independence. These results suggest that the full development of flight skills is not a constraining factor during the PFDP and that it is advantageous for juveniles to choose to remain in their natal territory. We posit that parents' tolerance of fledged juveniles is a type of parental care that may maximize their own fitness by improving the survival of their descendants. In future studies, it may be of interest to investigate the factors that may explain the high variability in the duration of this stage between individuals within the same population. [ABSTRACT FROM AUTHOR]

Natal dispersal of large raptors is poorly understood, despite being a crucial transitional life-cycle phase affecting gene flow and population dynamics. A research-gap rarely examined concerns how young dispersing raptors strategize movements towards first settlement on a prospective breeding territory. First territory settlement is a critical decision for a lifetime and can take several years. With such importance, large raptors should theoretically devote considerable effort to acquire accurate information during prospection. Nevertheless, when discovery of territorial opportunities may be difficult, but easier in vacant territories, we posit two extremes in strategizing prospection behaviours: (1) "Quick, grab it when available with limited reconnaissance," as opposed to (2) "Slow, waiting game with frequent reconnaissance". We analysed pre-settlement data from 37 GPS-tagged nestling golden eagles, later recorded as having settled on their first territory. The number of eagles' unique daily visits to their later settled territories was a measure of prospection intensity. We documented substantial variation in prior visits, between less than 10 to several hundred. Analyses considered several potential predictors. We expected a positive association between number of prospecting visits and natal dispersal duration, since with more time to gather information there should be more visits. We also expected fewer prospecting visits in prior vacant territories. Neither of these expectations were supported. There was a non-significant tendency for more prospection visits by males. Our study provides novel information on a seldom-studied behaviour in a large raptor. It illustrates substantial variation in prospecting behaviour, but expectations of potential drivers behind this variation were not confirmed, urging further study. [ABSTRACT FROM AUTHOR]

Anthropogenic stressors can favor the occurrence of noninfectious disease that can be worsened by the impact of opportunistic pathogens, making the epizootiology of environmental diseases difficult to unravel. The incidence and impact of oral lesions in nestlings of a facultative scavenger species, the black kite Milvus migrans, were examined over seven breeding seasons in the highly degraded environment close to Madrid, Spain. We found an overall prevalence of 31% of nestlings with oral lesions, with no clear spatial pattern in nests with affected and unaffected individuals. The occurrence and number of oral lesions were negatively associated with nestling body condition and brood size. Broods, where all siblings had oral lesions, were smaller than those where some or all siblings were apparently healthy, suggesting that oral disease could be causing nestling mortality and, consequently, brood size reduction. In turn, nestling body condition was negatively affected by lesion occurrence, brood size, and laying date. Although these relationships were bidirectional, piecewise structural equation modeling analyses showed a greater negative effect of body condition on lesion occurrence than vice versa, indicating that nestlings in poorer body condition were more likely to develop oral lesions (which could contribute to aggravate their state of deterioration) than those in better condition. Nestlings from small broods were also more likely to have oral disease (directly or indirectly through their lower body condition) than nestlings from large broods. Nestlings that hatched last in the broods showed greater development stress than those that hatched first. Anthropogenic stressors could trigger poor body condition, and contribute to microbiota dysbiosis-related diseases. Although further research is needed to determine the consequences for the long-term fitness of individuals, actions should be taken to mitigate adverse conditions that may favor the appearance of environmental diseases associated with peri-urban areas, given their rapid expansion over natural areas. [ABSTRACT FROM AUTHOR]

Costs and benefits of brain lateralization may depend on environmental conditions. Growing evidence indicates that the development of brain functional asymmetries is adaptively shaped by the environmental conditions experienced during early life. Food availability early in life could act as a proxy of the environmental conditions encountered during adulthood, but its potential modulatory effect on lateralization has received little attention. We increased food supply from egg laying to early nestling rearing in a wild population of lesser kestrels Falco naumanni , a sexually dimorphic raptor, and quantified the lateralization of preening behavior (head turning direction). As more lateralized individuals may perform better in highly competitive contexts, we expected that extra food provisioning, by reducing the level of intra-brood competition for food, would reduce the strength of lateralization. We found that extra food provisioning improved nestling growth, but it did not significantly affect the strength or direction of nestling lateralization. In addition, maternal body condition did not explain variation in nestling lateralization. Independently of extra food provisioning, the direction of lateralization differed between the sexes, with female nestlings turning more often toward their right. Our findings indicate that early food availability does not modulate behavioral lateralization in a motor task, suggesting limited phenotypic plasticity in this trait. [ABSTRACT FROM AUTHOR]

Conservation translocations (e.g., restocking, reintroductions) represent efficient tools to prevent the extinction or favouring the return of previously extirpated populations into the wild. Evaluating demographic parameters of translocated populations is a key issue to assess and monitor their conservation status and to provide evidences useful to implement management actions aimed at long-term conservation results. We report first data on survival estimates and related mortality causes for a reintroduced population of Eurasian griffon vultures (Gyps fulvus) in the central-southern Apennine, Italy, from satellite telemetry data. Twenty vultures have been fitted with solar-powered Global Positioning System (GPS) tags in Pollino National Park (PNP, southern Italy, N = 9) and Monte Velino Reserve (MVR, central Italy, N = 11). Survival has been estimated on a total amount of 173,568 GPS fixes from December 2016 to October 2020 (1415 days) using the Fleming-Harrington estimator. Five, out of 20 vultures, died by poisoning (40%), collision with wind turbines (20%) and of unknown causes (40%). Two birds dispersed from MVR to France (though they later came back) and one from PNP to Croatia. Estimated survival rate across the whole study period was 0.709 (±0.11, SE; 0.523--0.961, 95% CI), and annual survival rate was 0.915 (±0.06, SE; 0.846--0.990, 95% CI). No significant differences in survival rates have been detected according to sex or age. As mortality in our study was mainly human-caused, we urge relevant institutions and agencies to strengthen and effectively establish anti-poison strategies, as well as implementing mitigation and prevention measures for the existing and planned wind farms. The establishment of a long-term viable population in the central-southern Apennines will depend upon both lower levels of human-caused mortality and habitat preservation. [ABSTRACT FROM AUTHOR]

Background: A high prevalence of parasites may result from life-long persistence of infection or from high reinfection rates. We have studied blood parasites in a breeding population of the accipitrid raptor, Eurasian sparrowhawk (Accipiter nisus), to determine parasite diversity and turnover. Methods: During this 7-year study, 210 adult Eurasian sparrowhawks breeding in the city of Prague were checked for parasites using several diagnostic methods. Results: In both female and male raptors, parasites of the genus Leucocytozoon were the most prevalent (92% and 85%, respectively) followed in decreasing order of prevalence by those of genus Trypanosoma (74% and 68%, respectively) and genus Haemoproteus (46% and 16%, respectively). The prevalence of all parasites increased with age in both sexes, with the females at each respective age having the higher prevalence. There was a positive association between Haemoproteus and Leucocytozoon infections. Persistence at the individual level was higher than incidence for Trypanosoma and Haemoproteus. In the case of Leucocytozoon and Trypanosoma, most individuals probably become infected in their first year of life or even before dispersal from the nest. The detected parasites belonged to Trypanosoma avium sensu stricto, Leucocytozoon sp. (haplotypes ACNI1 and ACNI3) and Leucocytozoon mathisi (haplotype ACNI4) and two new lineages of the Haemoproteus elani complex (ACCNIS6 and ACCNIS7). Detailed analysis of parasite lineages in individuals that were repeatedly sampled revealed lineage turnover that would otherwise remain hidden. Phylogenetic analysis revealed that the detected Haemoproteus belongs to a phylogenetically distant group whose taxonomic position requires further analysis. Conclusions: All three genera of blood parasites persist in infected individuals, thus enabling sustainability of vector transmission cycles. Prevalence increases with age; however, there is a high turnover of Leucocytozoon lineages. No clear evidence of parasite-induced mortality was found, and most of the individuals were infected early in life, particularly in the case of Leucocytozoon. [ABSTRACT FROM AUTHOR]

Stable isotope mixing models (SIMMs) are widely used for characterizing wild animal diets. Such models rely upon using accurate trophic discrimination factors (TDFs) to account for the digestion, incorporation, and assimilation of food. Existing methods to calculate TDFs rely on controlled feeding trials that are time‐consuming, often impractical for the study taxon, and may not reflect natural variability of TDFs present in wild populations.We present TDFCAM as an alternative approach to estimating TDFs in wild populations, by using high‐precision diet estimates from a secondary methodological source—in this case nest cameras—in lieu of controlled feeding trials, and provide a framework for how and when it should be applied.In this study, we evaluate the TDFCAM approach in three datasets gathered on wild raptor nestlings (gyrfalcons Falco rusticolus; peregrine falcons Falco perigrinus; common buzzards Buteo buteo) comprising contemporaneous δ13C & δ15N stable isotope data and high‐quality nest camera dietary data. We formulate Bayesian SIMMs (BSIMMs) incorporating TDFs from TDFCAM and analyze their agreement with nest camera data, comparing model performance with those based on other relevant TDFs. Additionally, we perform sensitivity analyses to characterize TDFCAM variability, and identify ecological and physiological factors contributing to that variability in wild populations.Across species and tissue types, BSIMMs incorporating a TDFCAM outperformed any other TDF tested, producing reliable population‐level estimates of diet composition. We demonstrate that applying this approach even with a relatively low sample size (n < 10 individuals) produced more accurate estimates of trophic discrimination than a controlled feeding study conducted on the same species. Between‐individual variability in TDFCAM estimates for ∆13C & ∆15 N increased with analytical imprecision in the source dietary data (nest cameras) but was also explained by natural variables in the study population (e.g., nestling nutritional/growth status and dietary composition).TDFCAM is an effective method of estimating trophic discrimination in wild animal populations. Here, we use nest cameras as source dietary data, but this approach is applicable to any high‐accuracy method of measuring diet, so long as diet can be monitored over an interval contemporaneous with a tissue's isotopic turnover rate. [ABSTRACT FROM AUTHOR]

Gray-bellied Hawk, Accipiter poliogaster (Temmink, 1824), is a rare forest dwelling raptor in South America. This hawk migrates from Paraguay and northern Argentina (Misiones) in the south to the equator for the winter. In Costa Rica this species has occasionally been recorded from a few localities. We present here a new record from a disturbed area in the northern lowlands of the country. Accipiter poliogaster may be a rare vagrant or an occasional visitor in Costa Rica, or it may be expanding its range northward into the country due to increases in disturbed land caused by humans. [ABSTRACT FROM AUTHOR]

Largely due to the small number of individuals in captivity, birds of prey remain an understudied, but promising group for animal cognition research. Variations on the classic string-pulling task have been applied across species to evaluate abilities such as associative learning, means-end understanding, and insight problem solving. Previous research has examined only a few species of raptor on the task such as the Harris's hawk (Parabuteo unicinctus), great grey owl (Strix nebulosa), and turkey vulture (Cathartes aura). Here, we explored how 1-3 individuals from each of seven raptor species (turkey vulture; barn owl, Tyto alba; western screech owl, Megascops kennicottii; eastern screech owl, M. asio; red-tailed hawk, Buteo jamaicensis; Swainson's hawk, B. swainsoni; and Harris's hawk) responded to a standardized vertical apparatus. Our goal was to replicate, diversify, and extend the literature by documenting how these different species approached the same problem. Two strings were tied around a perch, one of which was baited. Birds underwent multiple 60-min trials. At least one bird from four of the seven species retrieved the food reward. Three individuals retrieved the food consistently across trials, including the first recorded solving by a western screech owl. Birds displayed diverse apparatus-directed behaviors and solving methods which supported our predictions regarding sociality and predation method. We frame our findings as a roadmap for future researchers studying physical problem-solving by raptors. [ABSTRACT FROM AUTHOR]

Skeletal muscle weakness has been associated with different pathological conditions, including sarcopenia and muscular dystrophy, and is accompanied by altered mammalian target of rapamycin (mTOR) signalling. We wanted to elucidate the functional role of mTOR in muscle contractility. Most loss‐of‐function studies for mTOR signalling have used the drug rapamycin to inhibit some of the signalling downstream of mTOR. However, given that rapamycin does not inhibit all mTOR signalling completely, we generated a double knockout for mTOR and for the scaffold protein of mTORC1, raptor, in skeletal muscle. We found that double knockout in mice results in a more severe phenotype compared with deletion of raptor or mTOR alone. Indeed, these animals display muscle weakness, increased fibre denervation and a slower muscle relaxation following tetanic stimulation. This is accompanied by a shift towards slow‐twitch fibres and changes in the expression levels of calcium‐related genes, such as Serca1 and Casq1. Double knockout mice show a decrease in calcium decay kinetics after tetanus in vivo, suggestive of a reduced calcium reuptake. In addition, RNA sequencing analysis revealed that many downregulated genes, such as Tcap and Fhod3, are linked to sarcomere organization. These results suggest a key role for mTOR signalling in maintaining proper fibre relaxation in skeletal muscle. Key points: Skeletal muscle wasting and weakness have been associated with different pathological conditions, including sarcopenia and muscular dystrophy, and are accompanied by altered mammalian target of rapamycin (mTOR) signalling.Mammalian target of rapamycin plays a crucial role in the maintenance of muscle mass and functionality.We found that the loss of both mTOR and raptor results in contractile abnormalities, with severe muscle weakness and delayed relaxation following tetanic stimulation.These results are associated with alterations in the expression of genes involved in sarcomere organization and calcium handling and with an impairment in calcium reuptake after contraction.Taken together, these results provide a mechanistic insight into the role of mTOR in muscle contractility. [ABSTRACT FROM AUTHOR]

Light and noise often act as pollutants, but can also be used as tools for managing wildlife (e.g., sensory deterrents). Given that raptors are among the most threatened groups of birds, we expected there to be a moderate amount of applied research on their sensory ecology. We searched Web of Science and Google Scholar to quantify and classify the research that has been conducted on the applied sensory ecology of raptors. Of 32 studies assessing the effects of sensory pollution on raptors, we found that 10 studies examined effects of light pollution and 24 studies examined effects of noise pollution. Most of the studies regarding sensory pollution were of owls (21 studies). The United States was the site of the most noise pollution studies (seven studies) whereas Spain and Poland (two studies each) were sites of the most studies of light pollution. We found only seven studies that directly collected data regarding sensory deterrents. With so few studies examining applied aspects of the sensory ecology of raptors, we argue that effects of sensory pollution are poorly understood and the efficacy of sensory deterrents is largely unknown. Light and noise pollution are spreading across much of the globe. Applied research on the sensory ecology of raptors must be made a priority if wildlife managers are to conserve this imperiled group of birds. La luz y el ruido a menudo actúan como contaminantes, pero también se pueden usar como herramientas para manejar la fauna salvaje (e.g., disuasores sensoriales). Dado que las rapaces se encuentran entre los grupos de aves más amenazados, esperábamos que hubiera una cantidad moderada de investigación aplicada sobre su ecología sensorial. Realizamos búsquedas en Web of Science y Google Académico para cuantificar y clasificar la investigación que se ha realizado sobre la ecología sensorial aplicada de las rapaces. De 32 estudios que evaluaron los efectos de la contaminación sensorial en las rapaces, encontramos que 10 estudios examinaron los efectos de la contaminación lumínica y 24 estudios examinaron los efectos de la contaminación sonora. La mayoría de los estudios sobre contaminación sensorial fueron de búhos (21 estudios). Estados Unidos fue el sitio con la mayor cantidad de estudios de contaminación sonora (siete estudios), mientras que España y Polonia (dos estudios cada uno) fueron los países con la mayor cantidad de estudios de contaminación lumínica. Solo encontramos siete estudios que tomaron datos directamente con respecto a los disuasores sensoriales. Con tan pocos estudios que examinan los aspectos aplicados de la ecología sensorial de las rapaces, argumentamos que los efectos de la contaminación sensorial son poco conocidos y que se desconoce en gran medida la eficacia de los disuasores sensoriales. La contaminación lumínica y sonora se está extendiendo por gran parte del mundo. La investigación aplicada sobre la ecología sensorial de las rapaces debe ser una prioridad si los gestores de fauna silvestre quieren conservar este grupo de aves en peligro. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

Divergent life histories by sex are common within species of birds; thus, the ability to accurately determine sex is essential in many studies of avian ecology and can possibly lead to more effective conservation strategies. However, sex determination can be difficult in species not displaying dimorphic plumage, including most raptors, and size dimorphism has limited use during observations but is promising for determining sex of raptors in hand. The Broad-winged Hawk (Buteo platypterus), known for its long-distance migrations between North and South America, has yet to be examined for morphometric variation across its wide range. We analyzed body mass, wing chord, and tail length data for 119 adult Broad-winged Hawks captured in eastern North America during the breeding seasons from 1974 to 2020. We found that adult female Broad-winged Hawks were larger than adult males overall. Hawks from Wisconsin were larger than hawks from Pennsylvania and Maryland, and hawks from Ontario were larger than those from other populations, suggesting geographic variation in size. Using linear discriminant analysis, we showed that it was possible to determine sex of adults with 99% accuracy in Wisconsin populations using only body mass as a predictor, and 100% accuracy in Pennsylvania and Maryland populations using body mass, wing chord, and tail length as predictors. Morphometric measurements combined with discriminant function analysis proved useful in discerning sex of breeding-season Broad-winged Hawks, and results of this study can guide researchers working in similar regions. We encourage researchers to collect body measurements for this species and other monomorphic raptors to further inform sex determination. Las historias de vida divergentes según el sexo son comunes en aves, por lo que la capacidad de determinar con precisión el sexo es esencial en muchos estudios de ecología aviar y posiblemente puede conducir a estrategias de conservación más efectivas. Sin embargo, la determinación del sexo puede ser difícil en especies que no muestran dimorfismo de plumaje, incluida la mayoría de las aves rapaces, y el dimorfismo de tamaño tiene un uso limitado durante las observaciones, pero es prometedor para determinar el sexo de las aves rapaces en la mano. Buteo platypterus, conocido por sus migraciones de larga distancia entre América del Norte y América del Sur, aún debe ser estudiado para determinar la variación morfométrica a lo largo de su amplia área de distribución. Analizamos los datos de masa corporal, cuerda alar y longitud de la cola de 119 individuos de B. platypterus capturados en el este de América del Norte durante las temporadas reproductivas de 1974 a 2020. Encontramos que, en general, las hembras adultas de B. platypterus eran más grandes que los machos adultos. Los individuos de Wisconsin eran más grandes que los de Pensilvania y Maryland, y los individuos de Ontario eran más grandes que los de otras poblaciones, lo que sugiere una variación geográfica en tamaño. Usando un análisis discriminante lineal, mostramos que era posible determinar el sexo de los adultos con un 99% de precisión en las poblaciones de Wisconsin usando solo la masa corporal como predictor, y con un 100% de precisión en las poblaciones de Pensilvania y Maryland usando la masa corporal, la cuerda alar y la longitud de la cola como predictores. Las mediciones morfométricas combinadas con análisis de función discriminante demostraron ser útiles para discernir el sexo de B. platypterus en la temporada reproductiva, y los resultados de este estudio pueden guiar a los investigadores que trabajan en regiones similares. Alentamos a los investigadores a recopilar medidas corporales de esta especie y de otras rapaces monomórficas para avanzar en la determinación del sexo. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

The Red Kite has come to the forefront of general consciousness in recent decades. A major contributing factor has been repeated collisions of these raptors with wind turbines and the important role they play in the approval process for new turbines. Efforts to improve their protection sometime encounter challenges due to limited knowledge about some life history aspects, e.g., their flight altitude and flight activity. We investigated these parameters from 2012 to 2018 in an approximately 1000-km2 study area in the vicinity of Weimar (Federal State of Thuringia, Federal Republic of Germany) in 29 breeding birds (19 males and 10 females) equipped with GPS loggers. In addition to more than 11 million GPS data records, accelerometer data from the loggers were evaluated. The start of morning activities correlated with sunrise. Most frequently, Red Kites initiated their first hunting flights immediately at sunrise; males started hunting at 9 min and females started hunting at 12 min after sunrise (medians). The Red Kites mostly foraged and hunted their prey during flight. The proportion of time spent flying during their activity phase was highest during midday hours, reaching 30–80% in males depending on the phase of the breeding season. For males, the time spent flying was approximately two and a half times that for females. The birds sporadically reached flight altitudes of up to 1600 m above ground in the breeding area, while they maintained lower altitudes between 5 and 60 m more frequently and predominantly while foraging (56% of location fixes). Higher altitudes were occupied much less frequently than lower altitudes and were often used to travel relatively long distances in an energy-saving manner. The end of activity was well before sunset, at 87 min prior to sunset for males and 154 min prior to sunset (medians) for females. [ABSTRACT FROM AUTHOR]

Bearded Vultures deliberately stain their feathers with iron oxides from ferruginous springs (FS) to acquire orange colouration. This uncommon behaviour is believed to play an important role in the relationship between individuals, so FS may constitute a strategic resource for the species. In the French Central-Western Pyrenees, we surveyed and mapped FS, checked those used by Bearded Vultures and characterised their habitat variables and geological features. We also evaluated FS availability in Bearded Vultures’ home ranges and their conservation status. FS occurred in relatively large number (more than three hundred) in the study area, spatially distributed in a very heterogeneous way. Sedimentary or metamorphic rocks dating from the Palaeozoic Era (–541 to –252 million years ago) hold majority of them, with schists being the predominant rock type (62.1%). FS were near absent from limestone massifs of the North-Pyrenean zone and from granite formations of the axial zone. We found evidences of use by Bearded Vultures in a limited number of sites (n = 27 out of 339 localised FS). These colouring sites were characterised by steep slopes, intense coloured iron oxide deposits and a location usually close to the forest edge. Availability of colouring sites for breeding Bearded Vultures (n = 32 pairs or trios in the study area) was high enough: we localised a mean of 36.9 available FS and 2.6 used FS in a 15 km-radius around the usual breeding site of each pair/trio. The mean distance between a breeding site and the nearest known colouring site was 8.8 ± 0.86 km, a minor flight distance for this species. The conservation status of the used FS seems generally satisfactory, although one site disappeared due to drought and three others were damaged by domestic livestock trampling or wild ungulates. The vicinity of cables or fences, i.e. potential mortality factors, also concerns three of the used FS. We recommend to consider these colouring sites as key resources for the species and to protect them from any damage. [ABSTRACT FROM AUTHOR]

Somatostatin-expressing interneurons (SOM-INs) are a major subpopulation of GABAergic cells in CA1 hippocampus that receive excitation from pyramidal cells (PCs) and provide feedback control of synaptic inputs onto PC dendrites. Excitatory synapses from PCs onto SOM-INs (PC-SOM synapses) exhibit long-term potentiation (LTP) mediated by type 1a metabotropic glutamate receptors (mGluR1a). LTP at PC-SOM synapses translates in lasting regulation of metaplasticity of entorhinal and CA3 synaptic inputs on PCs and contributes to hippocampus-dependent learning. A persistent form of PC-SOM synapse LTP lasting hours is prevented by blockers of transcription and translation, and a more transient form of PC-SOM synapse LTP lasting tens of minutes requires mTORC1-signaling, suggesting an involvement of protein synthesis. However, the role of protein synthesis in these forms of plasticity has not been directly demonstrated. Here we use the SUrface SEnsing of Translation (SUnSET) assay of protein synthesis to directly show that the induction protocols for both forms of LTP at PC-SOM synapses stimulate protein synthesis in SOM-INs. Moreover, protein synthesis stimulated by persistent LTP induction was prevented in mice with a SOM-IN conditional knock-out of Raptor, an essential component of mTORC1, indicating a critical role of mTORC1 in the control of translation in PC-SOM synapse plasticity. Moreover, protein synthesis induced by both forms of LTP may share common mechanisms as transient LTP induction occluded further stimulation of protein synthesis by persistent LTP induction. Our findings highlight a crucial role of protein synthesis and its control by mTORC1 in SOM-INs that is important for hippocampus-dependent memory function. [ABSTRACT FROM AUTHOR]