Eagle Nests Research Articles

A non‐invasive genetic approach for estimating the apparent survival rate of a long‐lived territorial raptor: a case study on the Golden Eagle Aquila chrysaetos

For long‐lived species, adult survival is the parameter that theoretically has the strongest impact on population dynamics; this makes its estimate crucial for conservation management. The use of non‐invasive genetic approaches coupled with capture–recapture methods is being used increasingly to estimate adult survival. Despite being regularly employed in mammals, it has been little‐used in birds and notably in long‐lived territorial species. This study aimed to determine if feathers obtained from eagle nests could be used to estimate the adult apparent survival rate and the costs associated with such an approach. Feather samples (n = 180) were collected in nests (n = 78) and directly from individual Golden Eagles (n = 36) Aquila chrysaetos in France and were genotyped using 17 microsatellite markers. The genotyping error rates obtained were low, with 3% amplification failures, 3.1% dropouts and 1.7% false alleles. The genetic variability of the markers was high, with a probability of identity between siblings of 6.8 × 10−6, allowing reliable individual identification. Of the feathers collected in nests, 90% were from breeding females; this allowed apparent survival to be estimated for adult females at a reasonable cost. The genotyping of three feathers collected from a nest ensured individual identification of the breeding female with near certainty. Our simulations showed that monitoring of at least 20 pairs over 5 years, or 10 pairs over 10 years is necessary to detect a 10% absolute decrease in adult apparent survival. Estimating the adult survival rate of long‐lived birds using feathers collected in nests is possible. A substantial budget, albeit one that is likely to be lower than that for a common capture–recapture survey, would be needed to obtain precise survival estimates.

Nesting Bald Eagle Population Numbers, Density, Territorial Resources, and Relationship to Human Development in Northern Colorado’s Front Range

To better understand the population of the Bald Eagle (Haliaeetus leucocephalus) nesting along northern Colorado’s Front Range, from 2016 to 2022 we studied 86 occupied nests within an area of 20,586 km2. From 2017 to 2020, 279 juveniles fledged from 237 nesting attempts in a smaller, main nest-study area with 68 nests. The nests’ success over these four years ranged from 52 to 70%, and their productivity varied from 1.1 to 1.3. The average nearest-nest distances for three discrete areas in the Front Range (5.03 to 7.26 km) are at least 2.8 to 4.0 times greater than these distances in four nesting populations in wetter regions but shorter than distances observed between nests in drier Arizona. In our study area the coverage of buildings within 400 m of Bald Eagle nests is relatively low by comparison to the coverage around randomly selected points, averaging 1344 m2; for 63% of the nests this coverage was less than 800 m2. We classified the 86 nest territories into eight categories that describe the dominant resource habitat and predicts the eagles’ reliance on Black-tailed Prairie Dogs (Cynomys ludovicianus) versus fish as prey. Predation on fish was predicted to be dominant at 51% (n = 44) of the nests, predation on prairie dogs at 32% (n = 28).

Nest Construction Costs Bald Eagles Time But not Breeding Success or Productivity

ABSTRACT 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.

Taphonomy of harpy eagle predation on primates and other mammals.

The goal of this study is to provide a taphonomic analysis of bone fragments found in harpy eagle nests in the Brazilian Amazonia, utilizing the largest sample of prey remains collected to date. Harpy eagle kill samples were collected from nine nests, between June 2016 and December 2020 in Mato Grosso, Brazil. We identified the specimens, calculated the number of identified specimens (NISP) and minimum number of individuals (MNI). These metrics were used to estimate bone survivability and fragmentation. A total of 1661 specimens (NISP) were collected, representing a minimum number of 234 individuals (MNI). We identified at least nine species of primates, which represent 63.8% of the individuals in the kill sample. Harpy eagles preyed mostly on the medium-sized capuchin and bearded saki monkeys (28.2% of the MNI), and two-toed sloths (17.7% of the MNI). The large woolly monkeys also represented a significant portion of the sample (11.5% of the MNI). Three distinct patterns of bone survivability were found, one characterizing two-toed sloths, another characterizing medium-sized monkeys, and a third typical of woolly monkeys. We conclude that harpy eagle predation leaves an identifiable signature on the prey with a bone survivability pattern specific to each taxon. The intertaxon variations observed in the taphonomic signatures of harpy eagle kills should be taken into account when evaluating the potential influence of these raptors as accumulators of bone material in both paleontological and neontological assemblages.

A mineral listening: digital soundscapes of geological time

Composed between 2020 and 2022 by Guillaume Malaret, Érodé is a musical piece created from field recordings at Eagles Nest, a tidal island in Australia’s Bunurong National Marine Park. Based on an interview with Guillaume Malaret, this article addresses several issues concerning digital representations, renderings, and ecologies of geological, hydrological, and sonic spaces, as well as the cultural geographies of landscape, embodiment, and affect. We explore the potentials of sonic composition and geophonic recordings for mediating bodily connections with difficult-to-imagine processes, such as environmental change over deep time. Our dialogue throughout this article contributes to emerging themes in digital ecological research by focusing on the materialities of digitization, digitally mediated creative practices in sonic geography, and the importance of different affective registers for comprehending environmental transformation.

The White-Tailed Eagle, the Apex Predator, Adjusts Diet towards Larger Prey in Suboptimal Territories

The White-tailed eagle, an apex predator, is currently recovering its populations across Europe and has already reached high numbers in many countries. This led to the saturation of eagles in optimal habitats and their encroachment on suboptimal ones. We aimed to compare the diet of White-tailed eagles in optimal and suboptimal conditions in northeastern Poland to investigate how population development affected prey composition, which is expected to be lacking in suboptimal eagle territories. We have monitored eagle nests with trail cameras to investigate their diet objectively and precisely. In order to compare territories of different quality, we have conducted modeling of habitat suitability using data on nest locations prior to their saturation. Using recorded photos of the prey, we measured their size and estimated their weight to check if the size and biomass of the prey are comparable between optimal and suboptimal territories. We found that eagles in the latter conditions were not limited by prey biomass but turned to alternative prey and brought larger prey. The alternative prey were large birds such as White storks and Common cranes, but also chicks of other avian predators that were robbed from their nests. Most probably, eagles cope with a lack of optimal prey by ranging farther and exploring non-optimal foraging habitats. We conclude that the diet flexibility of White-tailed eagle enables him to still increase its numbers despite already high densities. Our study also shows that this species might possibly impact the White stork population, as seen in the case of the Black stork and some seabird species.

Predation of turtles by bald eagles (Haliaeetus leucocephalus) in the Southeastern United States

Understanding complete ecological roles of species requires insight into various predator-prey relationships. Bald eagles (Haliaeetus leucocephalus) have been documented to consume a variety of species, including turtles. The ground beneath eight bald eagle nests located in Alabama and Tennessee were searched during the 2016, 2017, and 2018 nesting seasons for discarded turtle remains. Six turtle genera were documented, but the most abundant turtle genera observed were Graptemys and Sternotherus. Most remains were juveniles or adult males; however, the Sternotherus remains could have been adult males or females. The distance of the eagle nest to the nearest major waterway appeared to influence whether Graptemys or Sternotherus was the major turtle prey observed. The presence of different contaminants in these turtle species should be examined to determine if they potentially contribute to biomagnification in bald eagles.

Trypanosomatids in Bloodsucking Diptera Insects (Ceratopogonidae and Simuliidae) Wild-Caught at Raptor Bird Nests in Temperate Forests

Trypanosomatids are a huge group of vertebrate, invertebrate and plant parasites that can cause severe illnesses in hosts. Although avian trypanosomes are widely spread throughout the world, information about their transmission and vector–host relationships is still scarce. This study aimed to investigate Trypanosoma prevalence in bloodsucking Diptera collected at tree-nesting raptor birds’ nests. Insects were collected in temperate forests of Eastern-Central Europe, in Lithuania, using UV light traps hung near common buzzard (Buteo buteo) and lesser spotted eagle (Clanga pomarina) nests at about 15 m height above the ground. A total of 1248 Culicoides (Ceratopogonidae) females and 3 blackflies (Simuliidae) were collected and tested for the presence of trypanosomatids using PCR-based methods. The blood of 85 nestlings, belonging to three different species (Buteo buteo, Clanga pomarina and Haliaeetus albicilla) was collected and tested using the same methods. We found that 11.1% of the investigated insects (one Simulium female and Culicoides biting midges belonging to five species) were infected with Trypanosoma parasites (Trypanosoma sp., T. bennetti group, T. avium) and monoxenous trypanosomatids (Crithidia sp., Obscuromonas sp.). Only one common buzzard nestling was found to be infected with Trypanosoma avium. The phylogenetic relationships of detected parasites were determined. Our findings supplement information on the ornithophilic behavior of Culicoides females, potential vector species of avian Trypanosoma, and produce some new information on the detection of monoxenous trypanosomatids (Crithidia sp. and Obscuromonas sp.) in Culicoides.

Changes in Bald Eagle Nesting Distribution and Nest-Site Selection in Kentucky during 1986–2019

Kentucky's breeding Haliaeetus leucocephalus (Bald Eagle) population began recovering in 1986, with a single nest, and has since expanded from the state's western portion to the central and eastern regions. We used aerial survey data to describe the spatiotemporal distribution of Bald Eagle nests in Kentucky, to examine changes in nest-site selection relative to natural and anthropogenic features, and to create a nesting-habitat suitability model. Our results highlight increased nesting near developed areas in recent years. Although nests in these areas productively contribute to populations, we note some considerations of increased risks associated with nesting in developed areas. We also provide predictions of available nesting areas and data to direct the future monitoring and management of Bald Eagles in Kentucky.

Modeling current and future habitat suitability of an iconic bird to inform restoration planning in southeastern Louisiana, U.S.A.

Louisiana is facing a land loss crisis with 5,000 km2 lost since the 1930s, and another 10,000 km2 may disappear over the next 50 years. In response, the state developed a Comprehensive Master Plan for a Sustainable Coast, which includes predictions for how wildlife species respond to futures with or without restoration action. However, the 2017 Master Plan did not include a bird species representative of brackish or freshwater wetland habitats. Our objective therefore was to evaluate the potential for the Bald Eagle (Haliaeetus leucocephalus) to serve as an indicator of freshwater wetland health, and to develop a model to predict Bald Eagle responses to land cover change 20 and 50 years into the future, with or without restoration action. Using nest location data collected by the Louisiana Department of Wildlife and Fisheries from the Barataria Basin, we modeled the relationship between Bald Eagle nest occurrence and land cover using boosted regression trees. Model performance was strong, explaining 54.4 ± 0.1% of the deviance in nest occurrence, and showed that Bald Eagle nests were more common in areas with greater fresh forested wetland, freshwater marsh, and flotant marsh land cover. Future suitability for nesting Bald Eagles was higher in 20 and 50 years with restoration action compared to without, although suitability in both years was lower than contemporary suitability, regardless of restoration action. Our model suggests that comprehensive restoration action is needed, including the implementation of Mississippi River diversions, to sustain high densities of nesting Bald Eagles in coastal Louisiana.

Bald eagle mortality and nest failure due to clade 2.3.4.4 highly pathogenic H5N1 influenza a virus

The bald eagle (Haliaeetus leucocephalus) is a culturally and ecologically vital species in North America that embodies conservation success but continues to face threats that include emerging pathogens. The introduction of A/goose/Guangdong/1/1996 lineage highly pathogenic (HP) clade 2.3.4.4b H5N1 influenza A virus (IAV) in North America in late 2021 resulted in high rates of mortality among bald eagles. Here we show an alarming rate of bald eagle nest failure and mortality attributed to HP IAV. We documented fatal, systemic HP IAV infection in breeding adult and nestling bald eagles along the southeastern U.S. coast. Concurrently, annual bald eagle nest surveys in Georgia and Florida revealed a precipitous drop in success in coastal counties compared with previous years, portending negative impacts on population recruitment. As an apex predator and efficient scavenger, it is likely that bald eagles become infected through consumption of infected waterfowl. These results and similar reports of raptor mortality in Europe, Asia, and Africa, indicate a clear threat to raptor health. The possible long-term persistence of HP H5N1 IAV in North America poses an impending threat to bald eagle populations not only related to direct mortality but also decreased recruitment and warrants continued efforts to understand these potential impacts.

Гнездовые группировки орлов на ключевой орнитологической территории «Чинк Донызтау» в 2022 году

Гнездовые группировки орлов на ключевой орнитологической территории «Чинк Донызтау» в 2022 году

Некоторые особенности гнездования орлов на территории ГНПП «Буйратау», Казахстан

Republican state institution “State National Park “Buiratau” (hereinafter referred as SNNP “Buiratau”) was created on March 11, 2011, in Ereymentau district of the Akmola region and the Osakarovsky district of the Karaganda region. Based on the analysis of literary sources and our observations, it can be assumed that about 227 bird species from 18 orders, including 19 species from the bids of prey (Minakov et al., 2019) can be encountered here. Since the Park formation, we began to mark raptor nests on its territory. Since 2022, together with the Biodiversity Research and Conservation Center (BRCC), we have been monitoring nest occupancy for three eagle species known to us: Golden Eagle (Aquila chrysaetos), Eastern Imperial Eagle (Aquila heliaca), Steppe Eagle (Aquila nipalensis). 31 eagle nests are known on the territory of Buiratau State National Park and its protective zone, of them 14 belonging to Eastern Imperial Eagle, 8 – to Golden Eagle, and 9 – to Steppe Eagle. For the period of 2022–2023, the number of identified inhabited nests (belonging to nesting pairs, used for nesting in a given year) changed slightly. For Eastern Imperial Eagle, it increased from 6 to 7, for Golden Eagle it increased from 1 to 3, for Steppe Eagle it remained the same, 3 breeding pairs. Encounters were recorded during eagle nests monitoring, indicating unusual, in our opinion, timelines of nesting for Golden Eagle and Eastern Imperial Eagle. For example, on May 26, 2023, we discovered a clutch of three Golden Eagle eggs in a nest on a cliff face on a 6 m high rock. The number of eggs in a clutch indicated that it was not a repeated one. Literary sources indicate that in Northern and Central Kazakhstan Golden Eagle starts laying eggs in the early April (Bragin, 1987). According to A.I. Marakshin, Golden Eagle nest with one egg was found near Zerenda on April 24 (Korelov, 1962). Thus, the Golden Eagle nest with a clutch located on May 26, 2023, can be considered late. It is unknown what could have caused the delay in the onset of reproduction of this Golden Eagle pair. On June 1 of the same year, one month old nestlings were observed in another Golden Eagle nest built on a birch tree.

Культ орла в мифологии хангаласцев

Культ орла в мифологии хангаласцев

Орёл-могильник на юго-востоке Казахстана в 2022–2023 годах: распространение, численность, угрозы

Орёл-могильник на юго-востоке Казахстана в 2022–2023 годах: распространение, численность, угрозы

Первый опыт использования фотоловушки при изучении гнездовой биологии и экологии змееяда в Национальном парке Алтын Эмель в 2023 году

A Short-Toed Eagle (STE, Circaetus gallicus) nest was observed over the reproductive period of 2023 in Altyn-Emel National Park located in the south-east of Kazakhstan (Zhetysus oblast of the Republic of Kazakhstan). The nest location was on the right bank of the Ile River in arid terrain of clay conglomerate, 12–15 km east of the dry lowland massif of Ulken Kalkan (Ile Forestry section “Zhagalybai”) near the “Kosbastau” area. The nest was built on a live Turanga poplar (Populus diversifolia) about 5 m high on one of two dried branching trunks in the apex of the tree at a height of 3.7 m. Judging by the massiveness of the nest, this was not the first year that this pair of Short-Toed Eagles nested here. A nest of Saxaul Sparrow (Passer ammodendri) was located 50 m away on another turanga tree in a hollow formed by the fall of a dry branch (fully-feathered nestlings observed May 8). At least one pair of Indian Sparrows (Passer indicus) was nesting in the mass of the STE nest. One egg was observed in the STE nest on May 8, which represents a complete clutch, characteristic of the species. On the same day a camera trap (Digital Trail Camera HH-662, 16mp) with a combined trigger mode (3 images and 20-second video with a 20 min delay interval) was installed on a dry turanga poplar 1.7–2.0 m from the nest. Over the next three months, from 8 May to 10 August of this year, the incubating pair, and subsequently the hatched nestlings, were observed, until the nestlings fledged, though regularly returned to the nest from 10–15 August. To note, these were fragmentary, rather than constant observations by the camera trap due to the fact that the installed flash drive was periodically completely filled up and the charge of AA alkaline batteries ran out multiple times. Both individuals of the pair tolerated the close proximity of the camera trap almost immediately, and the camera trap recorded the pair taking turns at egg incubation as early as May 10. They sometimes changed turns in the early morning hours, almost immediately after sunrise. During egg incubation, one of the adults brought a freshly broken 70 cm twig of Elaeagnus (Elaeagnus oxycarpa) with leaves and ripening fruit to the nest when taking over incubation from its partner. On June 26, a nestlings covered in white down was observed in the nest. It also had pin feather stubs and opening pin feathers (pin feathers that are open by one-quarter to one-third) of flight feathers and contour feathers and back plumage that had already begun to open. It also had pins among the downy plumage on the head. When checked on July 19, the nest box contained an almost fully feathered nestlings, with growing remex and rectrix feathers. At times it actively flapped its fully opened wings while bouncing in the nest, evidently preparing to fledge. Both adults fed the nestlings on various species of snakes, including the Arrow Snake (Psammophis lineolatus) observed on July 3 and 14, Sand Boa (Eryx tataricus) observed on July 12, and Rat Snake (Elaphe dione) observed on July 7 and 15. Notably, the nestlings used its beak to pull the snakes out of the throat and esophagus of the parents, who had at that point swallowed the snake by half or even completely (July 3, 6, 7, 12, 15), at the same time the nestlings, helping itself, sometimes grasped the pulled snake with one of its paws (July 7). The recorded frequency and abundance of snake prey items may indirectly indicate a relatively high occurrence and abundance of snakes on the territory of the national park in its coastal part and quite a rich prey base of these reptiles in contrast to the neighboring geographical area in the Southern Pribalkhashie, where Hedgehogs (Erinaceus auritus) prevailed as prey items at the stage of feeding the fledged chick. Among the prey items of STEs recorded by camera trap (photos and video) in Altyn-Emel in 2023, hedgehogs were not recorded. Notably, on July 9, the nestlings began to pull sharply the end of tail from the beak of the adult, practically in the same way as in cases with snakes brought by parents, and the adult then regurgitated a nearly completely swallowed adult male steppe agama (Trapelus sanguinolentus). The authors are grateful to Alisher Kanapiy and Kanat Ospankul for their assistance with the field research, installation and periodic checking of the camera trap.

Крупные хищные птицы в заповеднике «Нургуш», Кировская область, Россия

Крупные хищные птицы в заповеднике «Нургуш», Кировская область, Россия

Орлы в государственном национальном природном парке «Бурабай»

From August 20 to September 17, 2022 and in the spring of 2023, the authors conducted ornithological research in the State National Natural Park “Burabay”. In the course of the research, information was obtained on encounters with eagles in the territory of the park. Imperial Eagles (Aquila heliaca) were observed throughout the area on a daily basis. A total of 44 observations were recorded during the research period, some of which were definitely migrants rather than local breeding birds. Only four out of 44 individuals observed were this year's birds. To the northeast of Big Chebachee Lake on 14/09/2022, adult birds were feeding a nestling, indicating the presence of a breeding territory of eagles here. In April 2023, a nest with two eggs was found. A large eagle nest, presumably of the Golden Eagle (Aquila chrysaetos), was found in the forest north of Zhukey Lake in the 40th district on September 6, 2022. The nest was located on an old pine tree and was approximately 1.5 m in diameter. Bone remains of prey and feathers of various birds of prey (e.g. Buzzards Buteo buteo) were found under the nest. Shortly afterwards, an eagle, identified by us as this year's Golden Eagle, wasseen in the vicinity of the nest, and on 13/09/2022 an adult bird was observed between the lakes Maloye Chebacheeand Bolshoye Chebachee, north of Lake Maibalyk. An adult Greater Spotted Eagle (Aquila [Clanga] clanga) was observed near the Kairaktin Forest District on 26/08/2022. The bird was carrying food in its beak to a juvenile bird calling from the forest (Becker/ebird.org; Wassink, 2023). This is the first case of breeding of the Greater Spotted Eagle in the State National Natural Park «Burabay». Another juvenile bird, uncertainly identified as the Great Spotted Eagle, was seen a few hours later about 12 km south of the previous encounter site. The Steppe Eagle (Aquila nipalensis) was observed twice, once on 25/08/2022 in Saule aul and once on 05/09/2022 over Ulkensor Lake. Steppe eagles are likely to be migrants or nomads within the Park after the breeding season, but do not breed in the Park. The Booted Eagle (Hieraaetus pennatus) was observed four times, on August 22 and 23 in the territory of Barmashinskoye Forestry, and on September 8 and 15, 2022 in the vicinity of Borovskoye Forestry, with birds of both light and dark morphs (Becker/ebird.org). In addition, on 21/07/2021, the Booted Eagle was recorded by a trap camera set up in the forest between Burabay and Sarybulak (Wassink, 2023). The nearest known breeding territory is located approximately 430 km to the southeast in Bayanaul National Park (Reznichenko, 2012; 2020). Proposed measures for the conservation of the considered bird species on the territory of the State National Natural Park «Burabay»: – introduce a ban on any logging within a radius of 1.5 km from eagle breeding territories; – sanitation cutting, with mandatory reforestation of native tree species, only after nestlings have learned to fly; – limit the presence of livestock and people within 500 m of eagle nests during the breeding season; – during the incubation period and before fledglings take wing, inspectors should conduct daily rounds of the breeding areas (within 500 meters of the nests) to prevent possible violations by park visitors; – restrict watering of livestock on the banks of water bodies near eagles' nests.

Первые шаги в сохранении степного орла в центральной части Костанайской области с использованием искусственных гнездовий (Республика Казахстан)

The Steppe Eagle (Aquila nipalensis) nests across a great swath of Kostanay Oblast. The greatest number and density of nesting pairs is concentrated in to the south. Northernmost nesting points are located in Kamysty, Auliekol and Naurzum districts, located centrally in the oblast. In July 2023 Naurzum Community Environmental Organization initiated a project jointly with Naurzum State Nature Reserve and with the financial support of the Global Greengrants Fund to install nesting platforms for Steppe Eagles. The project area covers the districts of Nauru and southern Auliekol. Naurzum State Nature Reserve is also located here and has great importance for biodiversity conservation in the region. There are 10–12 Steppe Eagle nesting sites located directly within the reserve and its buffer zone, and another 8–10 sites on adjacent territories. Among the threats facing Steppe Eagles, fire is the biggest issue, often burning large areas. Another challenge is periodic decline in food supply, generally resulting from mainly epizootic disease in the Little Ground Squirrel (Spermophilus pygmaeus). To a lesser extent, the Destruction of nests by predators and domestic animals, as well as bird-hazardous power lines also have negative impacts, albeit to lesser extents. 34 nesting platforms will be installed in the reserve’s buffer zone and adjacent areas as part of the project. Installation sites include both active nesting sites for birds and prospective areas to attract new pairs.

Питание беркута на средней Лене, Якутия, Россия

Presented data on the Golden Eagle (Aquila chrysaetos) diet is based on the analysis of 291 pellets and 233 food remains found in or under nests and perches. Data was also obtained based on visual information. Small rodents were identified by teeth structure, birds – by femur and humerus sizes. If possible, species was determined by mammal hairs and bird feathers found in pellets or food remains. Information on the Golden Eagle diet was obtained between 2006 and 2023 in three administrative areas of Yakutia (Khangalassky and Namsky districts, administrative area of the city of Yakutsk) located in the basin of the middle reaches of Lena (Middle Lena). The study area has a wide and complexly terraced valley, 70% of which is covered by taiga with combination of coniferous (larch, spruce, pine) and small-leaved (willow, birch) forests, meadows, and agricultural land. The Middle Lena is characterized by an extremely continental climate and a short summer: average temperature in January is -43.2°, in June – +18,0°, frostfree period lasts 95 days. Previously Golden Eagle nested throughout the taiga of Yakutia, and until the early 1960s was a common species in the Middle Lena (Vorobiev, 1963). Since the 1970s–1980s a sharp decrease in its abundance was recorded, and since the 1990s it has become extremely rare (Solomonov, Larionov, 1976; Borisov, 1987; Isaev et al., 2020). According to our observations, since the beginning of the 2000s there was a gradual increase in the number of Golden Eagle and the emergence of breeding territories in areas where Golden Eagles were absent for a long-time during breeding period. Today, 33 Golden Eagle nests are known in the Middle Lena, breeding occurred in 11 of them. The Golden Eagle arrival is usually observed from the second decade of March to the first decade of April. Golden Eagle lays eggs in April, nestlings hatch in May and depart from nests in September–October. Research by Yu.V. Labutin (1992) shows that in the 1970s–1980s, the main food source for Golden Eagle in Central Yakutia was Mountain Hare (89%); according to G.P. Larionov et al., 1991, in the 1980s–1990s this species accounted for 37.7% of prey. It should be noted that in the beginning-middle of the 20th century, Mountain Hare was one of the most common species in Central Yakutia, and in years of its peak abundance – massive commercial species, as almost 850,000 hare skins were harvested then. A steady downward trend in the number of species has begun from the 1970s, the population size has decreased, mainly due to the anthropogenic factor (Solomonov, 1975). Since 2000s, hare hunting has ceased due to its low numbers in the region. Accounting that has been carried out in Central Yakutia in 2008–2018 showed that the number of species is very low – 0.2–0.3 individuals/10 km of the route (Sedalishchev, Odnokurtsev, 2022). As shown by the recent data, 11 mammal and 29 bird species are found in the Golden Eagle diet in Central Yakutia, and Long-Tailed Ground Squirrel has become its main prey. The predominance of Ground Squirrels in the diet suggests that, due to an increase in hare abundance, Golden Eagle switched to species with higher population density. The diet of Golden Eagle changes depending on the season. The greatest prey variety is observed in spring; eagles feed on young Roe Deer, Ground Squirrels, less often – hare, sable, etc. There are also reports of Golden Eagles attacking exhausted adult Roe Deer in early spring. It is worth noting that, judging by the survey data, Golden Eagles were often observed near fallen horses. While horse hairs were found in only one of the examined pellets, it confirmed Golden Eagle feeding on horse meat. From the beginning of June, Golden Eagle switch to its main prey, the Long-Tailed Ground Squirrel, occasionally feeding on small mammals and passerine birds. Interestingly, insects are sometimes found in pellets collected in Golden Eagle nests.