Active European warzone impacts raptor migration.

Human conflicts can have impacts on wildlife, from direct mortality and environmental damage to the displacement of people, changing institutional dynamics and altering economies.1,2,3 Extreme anthropogenic disturbances related to conflict may act as a barrier to migrating birds and increase the energetic costs of migration.4 On February 24th, 2022, the Russian Federation invaded Ukraine, with targeted attacks on Kyiv and the eastern regions.5 By March 3rd, when the first of 19 tagged Greater Spotted Eagles entered Ukraine on migration, the conflict had spread to most major cities, including parts of western Ukraine.6 We quantified how conflict impacted the migratory behavior of this species using GPS tracks and conflict data from the Armed Conflict Location and Event Data (ACLED) project7,8 in a quasi-experimental before-after control-impact design, accounting for meteorological conditions. Migrating eagles were exposed to conflict events along their migration through Ukraine and exhibited different behavior compared with previous years, using fewer stopover sites and making large route deviations. This delayed their arrival to the breeding grounds and likely increased the energetic cost of migration, with sublethal fitness effects. Our findings provide a rare window into how human conflicts affect animal behavior and highlight the potential impacts of exposure to conflict events or other extreme anthropogenic disturbances on wildlife.

Bill shape variation in selected species in birds of prey.

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.

Implications of human-wildlife conflict on the diet of an endangered avian top predator in the northern Andes.

Conflicts between rural people and the Endangered Black-and-chestnut Eagle (Spizaetus isidori) are a prominent conservation concern in the northern Andes, as at least 60 eagles were poached between 2000 and 2022 in response to poultry predation. Here, we conducted direct observations to analyze the Black-and-chestnut Eagle diet and evaluated how forest cover affects the feeding habits of the species during nestling-rearing periods in 16 nests located in different human-transformed Andean landscapes of Ecuador and Colombia. We analyzed 853 prey items (46 species) delivered to nestlings. We used Generalized Linear Models to test whether the percent forest cover calculated within varying buffer distances around each nest and linear distances from the nest to the nearest settlement and pasture areas were predictors of diet diversity and biomass contribution of prey. Forest cover was not a factor that affected the consumption of poultry; however, the eagle regularly preyed on chickens (Gallus gallus) (i.e., domestic Galliformes) which were consumed by 15 of the 16 eagle pairs, with biomass contributions (14.57% ± 10.55) representing 0.6-37% of the total prey consumed. The Black-and-chestnut Eagle is an adaptable generalist able to switch from mammalian carnivores to guans (i.e., wild Galliformes) in human-dominated landscapes, and eagles nesting in sites with low forest cover had a less diverse diet than those in areas with more intact forests. Management actions for the conservation of this avian top predator require studies on the eagle's diet in areas where human persecution is suspected or documented, but also maintaining forest cover for the wild prey of the species, development of socio-economic and psychological assessments on the drivers behind human-eagle conflicts, and the strengthening of technical capacities of rural communities, such as appropriate poultry management.

Resource availability and diet in Harpy Eagle breeding territories on the Xingu River, Brazilian Amazon / Disponibilidade e consumo de presas por harpia no entorno de territórios de nidificação no rio Xingu, Amazônia Oriental Brasileira

Abstract In the Tapajos-Xingu interfluve, one of the largest birds of prey, the Harpy Eagle, is under intense anthropogenic pressure due to historical and recent reductions in forest cover. We studied prey availability and use by Harpy Eagle on six breeding territories on the low- and mid-Xingu River, between 2013 and 2015. We evaluated food resource availability using the environmental-surveys database from two methods: terrestrial surveys (RAPELD method) and fauna rescue/flushing before vegetation suppression for the Belo Monte Hydroelectric Complex construction. Harpy Eagle diet was identified by prey remains sampled around six nest trees. Eighteen species of mammals, birds and reptiles comprised the prey items. Most prey species were sloths, primates and porcupines, which have arboreal habits and are found in forested areas, but two species, hoatzin and iguana, are usually associated with riverine habitats. The proportion of prey from each species predated on the nest best studied was different from estimated availability (χ2 = 54.23; df = 16; p < 0.001), however there was a positive correlation (rs = 0.7; p < 0.01) between prey species consumed and abundance available, where the predation was more on species more abundant. Continuous monitoring of the Harpy Eagle diet at these nests could evidence changes in the assemblage of prey species available for Harpy Eagles, due to changes in the seasonal flood pulse of the Xingu River to be caused by the operation of the hydroelectric dam, and changes in habitat features by forest reduction around breeding territories. We believe that it is important to consider the protection of remnants of forested areas in the landscape matrix surrounding the breeding territories to maintain the food resource availability and allow all pairs to successfully reproduce.

Resumo O interflúvio Tapajós-Xingu, um dos centros de endemismo da Amazônia, onde habita uma das mais poderosas aves de rapina, a harpia, é também alvo de intensa pressão antrópica com reduções históricas da cobertura florestal. Analisamos a disponibilidade de vertebrados e o consumo de presas por harpia em seis territórios de reprodução no Rio Xingu, entre 2013 e 2015. A disponibilidade de recursos alimentares foi baseada nos dados de amostragens por dois métodos: levantamentos terrestres pelo método RAPELD e resgate/afugentamento da fauna antes da supressão da vegetação para construção de infra-estrutura para o Complexo Hidrelétrico Belo Monte. As espécies de presas consumidas pela harpia foram identificadas a partir de vestígios coletados em seis ninhos. Dezoito espécies de mamíferos, aves e répteis compuseram a dieta no baixo e médio Rio Xingu, com maior proporção de preguiças, macacos e porcos-espinhos, incluindo duas espécies (Opisthocomus hoazin e Iguana iguana) associadas aos hábitats criados por rios. A proporção de indivíduos das espécies predadas no ninho com maior número de coletas foi diferente da disponibilidade (χ2 = 54,23; gl = 16; p < 0,001), no entanto, existe correlação positiva (rs = 0,7; p < 0,01) entre o consumo de presas e a abundância disponível, com a predação maior sobre espécies mais abundantes. A riqueza de presas indica que as florestas remanescentes na região foram fonte eficiente de recursos alimentares para a reprodução e manutenção da harpia. O monitoramento da dieta da harpia nos ninhos pode apresentar alterações relacionadas às mudanças no pulso sazonal de inundação do Xingu, provocadas pelo futuro funcionamento da usina hidrelétrica e à redução da floresta no entorno dos ninhos localizados no Reservatório Xingu e Intermediário. É importante considerar a proteção dos remanescentes florestais no entorno dos territórios de nidificação para garantir a disponibilidade de presas e a reprodução efetiva dos casais de harpia na região.

Resource availability and diet in Harpy Eagle breeding territories on the Xingu River, Brazilian Amazon / Disponibilidade e consumo de presas por harpia no entorno de territórios de nidificação no rio Xingu, Amazônia Oriental Brasileira

In the Tapajos-Xingu interfluve, one of the largest birds of prey, the Harpy Eagle, is under intense anthropogenic pressure due to historical and recent reductions in forest cover. We studied prey availability and use by Harpy Eagle on six breeding territories on the low- and mid-Xingu River, between 2013 and 2015. We evaluated food resource availability using the environmental-surveys database from two methods: terrestrial surveys (RAPELD method) and fauna rescue/flushing before vegetation suppression for the Belo Monte Hydroelectric Complex construction. Harpy Eagle diet was identified by prey remains sampled around six nest trees. Eighteen species of mammals, birds and reptiles comprised the prey items. Most prey species were sloths, primates and porcupines, which have arboreal habits and are found in forested areas, but two species, hoatzin and iguana, are usually associated with riverine habitats. The proportion of prey from each species predated on the nest best studied was different from estimated availability (χ2 = 54.23; df = 16; p < 0.001), however there was a positive correlation (rs = 0.7; p < 0.01) between prey species consumed and abundance available, where the predation was more on species more abundant. Continuous monitoring of the Harpy Eagle diet at these nests could evidence changes in the assemblage of prey species available for Harpy Eagles, due to changes in the seasonal flood pulse of the Xingu River to be caused by the operation of the hydroelectric dam, and changes in habitat features by forest reduction around breeding territories. We believe that it is important to consider the protection of remnants of forested areas in the landscape matrix surrounding the breeding territories to maintain the food resource availability and allow all pairs to successfully reproduce.

RO interflúvio Tapajós-Xingu, um dos centros de endemismo da Amazônia, onde habita uma das mais poderosas aves de rapina, a harpia, é também alvo de intensa pressão antrópica com reduções históricas da cobertura florestal. Analisamos a disponibilidade de vertebrados e o consumo de presas por harpia em seis territórios de reprodução no Rio Xingu, entre 2013 e 2015. A disponibilidade de recursos alimentares foi baseada nos dados de amostragens por dois métodos: levantamentos terrestres pelo método RAPELD e resgate/afugentamento da fauna antes da supressão da vegetação para construção de infra-estrutura para o Complexo Hidrelétrico Belo Monte. As espécies de presas consumidas pela harpia foram identificadas a partir de vestígios coletados em seis ninhos. Dezoito espécies de mamíferos, aves e répteis compuseram a dieta no baixo e médio Rio Xingu, com maior proporção de preguiças, macacos e porcos-espinhos, incluindo duas espécies (Opisthocomus hoazin e Iguana iguana) associadas aos hábitats criados por rios. A proporção de indivíduos das espécies predadas no ninho com maior número de coletas foi diferente da disponibilidade (χ2 = 54,23; gl = 16; p < 0,001), no entanto, existe correlação positiva (rs = 0,7; p < 0,01) entre o consumo de presas e a abundância disponível, com a predação maior sobre espécies mais abundantes. A riqueza de presas indica que as florestas remanescentes na região foram fonte eficiente de recursos alimentares para a reprodução e manutenção da harpia. O monitoramento da dieta da harpia nos ninhos pode apresentar alterações relacionadas às mudanças no pulso sazonal de inundação do Xingu, provocadas pelo futuro funcionamento da usina hidrelétrica e à redução da floresta no entorno dos ninhos localizados no Reservatório Xingu e Intermediário. É importante considerar a proteção dos remanescentes florestais no entorno dos territórios de nidificação para garantir a disponibilidade de presas e a reprodução efetiva dos casais de harpia na região.

Abundance of Harpy and Crested Eagles from a reservoir-impact area in the Low- and Mid-Xingu River / Abundância de Gavião-real e Gavião-real falso numa área sob impacto de reservatório no Baixo e Médio rio Xingu

Abstract In the Brazilian Amazon, two monospecific genera, the Harpy Eagle and Crested Eagle have low densities and are classified by IUCN as Near Threatened due to habitat loss, deforestation, habitat degradation and hunting. In this study, we evaluate occurrence of these large raptors using the environmental surveys database from Belo Monte Hydroelectric Power Plant. Integrating the dataset from two methods, we plotted a distribution map along the Xingu River, including records over a 276-km stretch of river. Terrestrial surveys (RAPELD method) were more efficient for detecting large raptors than standardized aquatic surveys, although the latter were complementary in areas without modules. About 53% of the records were obtained during activities of wildlife rescue/flushing, vegetation suppression or in transit. Between 2012 and 2014, four Harpy Eagles were removed from the wild; two shooting victims, one injured by collision with power lines and one hit by a vehicle. Also, seven nests were mapped. The mean distance between Harpy Eagle records was 15 km along the river channel, with a mean of 20 km between nests near the channel, which allowed us to estimate 20 possible pairs using the alluvial forest, riverine forest and forest fragments. Territories of another ten pairs will probably be affected by inundation of the Volta Grande channel, which is far from the main river. The average distance between Crested Eagle records was 16 km along the river channel. The only nest found was 1.3 km away from a Harpy Eagle nest. The remnant forests are under threat of being replaced by cattle pastures, so we recommend that permanently protected riparian vegetation borders (APP) be guaranteed, and that forest fragments within 5 km of the river be conserved to maintain eagle populations.

Resumo Na Amazônia brasileira dois gêneros mono-específicos, Harpia e Morphnus, caracterizam-se por baixa densidade e estão classificados pelo IUCN como Quase Ameaçados, porém ocorrem sobre grande parte do território nacional, suas principais ameaças são a fragmentação florestal, a degradação de hábitat e a caça. Neste estudo avaliamos a abundância destas duas grandes aves de rapina utilizando a base de dados dos programas ambientais da UHE Belo Monte, integrando-se dois métodos para construir um mapa de distribuição ao longo de 245 km do rio Xingu. Os levantamentos terrestres pelo método RAPELD mostraram-se mais eficientes para os registros de grandes águias quando comparado aos esforços padronizados aquáticos, entretanto estes foram complementares na ausência de módulos. Cinquenta e tres por cento foram registros ocasionais durante a supressão da vegetação, afugentamento ou deslocamento. Entre 2012-2014 quatro harpias foram removidas da natureza, dois indivíduos alvo de disparos, uma por colisão com rede elétrica, e outra por atropelamento. Sete ninhos mapeados, a distância média entre os registros de harpia na calha e margens do rio foi de 15 km, 20 km distância média entre ninhos, o que permitiu estimar um total de 20 casais utilizando as florestas aluviais em uma distancia de 270 km, incluindo matas ciliares e os fragmentos fora da margem do rio. Estimamos que territórios de outros 10 casais usando a Volta Grande longe do rio principal também serão afetados pela inundação. A distância média entre os registros de Morphnus foi 16 km ao longo do rio, o único ninho mapeado estava distante 1.3 km do ninho de Harpia. Estes fragmentos florestais estão sendo substituídos por pastagens, ressaltando-se a importância da manutenção das áreas de preservação permanentes (APP) e a proteção destes fragmentos em diversos formatos de áreas de proteção, para diminuir a degradação dos mesmos e garantir a manutenção das populações destes grandes predadores na região do rio Xingu.

Abundance of Harpy and Crested Eagles from a reservoir-impact area in the Low- and Mid-Xingu River / Abundância de Gavião-real e Gavião-real falso numa área sob impacto de reservatório no Baixo e Médio rio Xingu

In the Brazilian Amazon, two monospecific genera, the Harpy Eagle and Crested Eagle have low densities and are classified by IUCN as Near Threatened due to habitat loss, deforestation, habitat degradation and hunting. In this study, we evaluate occurrence of these large raptors using the environmental surveys database from Belo Monte Hydroelectric Power Plant. Integrating the dataset from two methods, we plotted a distribution map along the Xingu River, including records over a 276-km stretch of river. Terrestrial surveys (RAPELD method) were more efficient for detecting large raptors than standardized aquatic surveys, although the latter were complementary in areas without modules. About 53% of the records were obtained during activities of wildlife rescue/flushing, vegetation suppression or in transit. Between 2012 and 2014, four Harpy Eagles were removed from the wild; two shooting victims, one injured by collision with power lines and one hit by a vehicle. Also, seven nests were mapped. The mean distance between Harpy Eagle records was 15 km along the river channel, with a mean of 20 km between nests near the channel, which allowed us to estimate 20 possible pairs using the alluvial forest, riverine forest and forest fragments. Territories of another ten pairs will probably be affected by inundation of the Volta Grande channel, which is far from the main river. The average distance between Crested Eagle records was 16 km along the river channel. The only nest found was 1.3 km away from a Harpy Eagle nest. The remnant forests are under threat of being replaced by cattle pastures, so we recommend that permanently protected riparian vegetation borders (APP) be guaranteed, and that forest fragments within 5 km of the river be conserved to maintain eagle populations.

Na Amazônia brasileira dois gêneros mono-específicos, Harpia e Morphnus, caracterizam-se por baixa densidade e estão classificados pelo IUCN como Quase Ameaçados, porém ocorrem sobre grande parte do território nacional, suas principais ameaças são a fragmentação florestal, a degradação de hábitat e a caça. Neste estudo avaliamos a abundância destas duas grandes aves de rapina utilizando a base de dados dos programas ambientais da UHE Belo Monte, integrando-se dois métodos para construir um mapa de distribuição ao longo de 245 km do rio Xingu. Os levantamentos terrestres pelo método RAPELD mostraram-se mais eficientes para os registros de grandes águias quando comparado aos esforços padronizados aquáticos, entretanto estes foram complementares na ausência de módulos. Cinquenta e tres por cento foram registros ocasionais durante a supressão da vegetação, afugentamento ou deslocamento. Entre 2012-2014 quatro harpias foram removidas da natureza, dois indivíduos alvo de disparos, uma por colisão com rede elétrica, e outra por atropelamento. Sete ninhos mapeados, a distância média entre os registros de harpia na calha e margens do rio foi de 15 km, 20 km distância média entre ninhos, o que permitiu estimar um total de 20 casais utilizando as florestas aluviais em uma distancia de 270 km, incluindo matas ciliares e os fragmentos fora da margem do rio. Estimamos que territórios de outros 10 casais usando a Volta Grande longe do rio principal também serão afetados pela inundação. A distância média entre os registros de Morphnus foi 16 km ao longo do rio, o único ninho mapeado estava distante 1.3 km do ninho de Harpia. Estes fragmentos florestais estão sendo substituídos por pastagens, ressaltando-se a importância da manutenção das áreas de preservação permanentes (APP) e a proteção destes fragmentos em diversos formatos de áreas de proteção, para diminuir a degradação dos mesmos e garantir a manutenção das populações destes grandes predadores na região do rio Xingu.