First Breeding Attempt of Golden Eagle (Aquila chrysaetos L.) in Lithuania

We newly found a collection of the Poaceae specimens deposited at the Herbarium of Vilnius University (WI), collected by Povilas Snarskis mainly from eastern Lithuania in 1943–1960. The collection consisted of 67 herbarium sheets representing 28 species, including endangered species Glyceria lithuanica. The collection provided new data on abnormal growth forms of common Lithuanian grasses and the distribution of rare and endangered Poaceae species in eastern and southern Lithuania. The discovered Glyceria lithuanica specimen is the oldest of all known records of the species in Lithuania.

Lead exposure from ingestion of bullet fragments is a serious environmental hazard to eagles. We determined blood lead levels (BLL) in 178 golden eagles (Aquila chrysaetos) captured during fall migration along a major North American flyway. These eagles spent the breeding season distributed over a large range and are the best currently available representation of free flying golden eagles on the continent. We found 58 % of these eagles containing increased BLL > 0.1 mg/L; 10 % were clinically lead poisoned with BLL > 0.6 mg/L; and 4 % were lethally exposed with BLL > 1.2 mg/L. No statistical difference in BLL existed between golden and bald eagles (Haliaeetus leucocephalus). Golden eagles captured on carrion had higher BLL than those captured using live bait suggesting differences in feeding habits among individuals. Median BLL increased with age class. We propose a conceptual model for the long-term increase in BLL after ingestion of lead particles. The mean blood mercury level in golden eagles was 0.023 mg/L. We evaluate a field test for BLL that is based on anodic stripping voltammetry. This cost-effective and immediate method correlated well with results from inductively coupled plasma-mass spectrometry, although results needed to be corrected for each calibration of the test kit.

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

Capsule The breeding season diets of White-tailed Eagles and Golden Eagles in western Scotland were different, and there was no evidence of competition between the two species. Aim To test the hypothesis that the reintroduced White-tailed Eagles will have an adverse effect on Golden Eagles through competition for food. Methods Collections of prey remains at nests and regurgitated pellets during the breeding season were analysed. Temporal change in Golden Eagle territory occupancy and breeding productivity where the influence of White-tailed Eagles should be most evident was also examined. Results Diet breadth was similar between species but diet composition was significantly different, with White-tailed Eagles taking more sheep and aquatic or coastal food items, whereas Golden Eagles took more gamebirds (Galliformes), lagomorphs and other terrestrial prey. Diet overlap comparisons, between species-pairs that nested close together or far apart, rejected a hypothesis that there was competition for food, but partially supported an alternative hypothesis that diet overlap indicated abundant shared food. There was no indication that White-tailed Eagles have had any long-term effect on the breeding productivity or abundance of territorial Golden Eagles. Conclusions There is no evidence that reintroduced White-tailed Eagles are having an adverse effect on Golden Eagles through competition.

Breeding territory of the Golden Eagle (Aquila chrysaetos) in the Berd river valley. Photo by O. Andreyenkov. Гнездовой участок беркута (Aquila chrysaetos) на р. Бердь. Фото О. Андреенкова. Берд өз. аңғарындағы бүркіттің (Aquila chrysaetos) ұя салу телімі. О. Андреенкованың фотосы.

PDF HTML阅读 XML下载 导出引用 引用提醒 基于动物适宜栖息地的北京市自然保护地保护成效评估 DOI: 10.5846/stxb202109022475 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31872240）；国家林业和草原局项目（2021080323-1）；北京绿色生态空间保护空缺分析项目（2021XJL02） Assess the conservation effectiveness of the natural protected areas in Beijing based on the suitable habitat of wild animals Author: Affiliation: Fund Project: The National Natural Science Foundation of China (General Program, Key Program, Major Research Plan) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:栖息地是野生动物赖以生存的基础，明晰物种的适宜栖息地分布是切实加强野生动物保护、提高生物多样性保护成效的重要基础。北京市野生动植物资源丰富，也建立了一系列自然保护地以加强对野生动物的保护。当前亟需系统评估北京市现有自然保护地体系对野生动物适宜栖息地的保护成效，为未来北京市野生动物保护管理和自然保护地体系整合工作优化提供科学指导。研究选取了北京地区6个较为典型的野生动物为主要研究对象，包括黑鹳（Ciconia nigra）、褐马鸡（Crossoption mantchuricum）、大鸨（Otis tarda）、鸳鸯（Aix galericulata）、金雕（Aquila chrysaetos）和斑羚（Naemorhedus griseus），利用MaxEnt模型和ArcGIS的空间分析功能分析其适宜栖息地的分布；将自然保护地与适宜栖息地相叠加，识别其适宜栖息地的分布热点和保护空缺，进而评估了北京市现有自然保护地体系的保护成效。研究结果表明，6个研究物种在现有的自然保护地体系中均得到了不同程度的保护，其中褐马鸡的受保护率最高（92.82%），鸳鸯的受保护率最低（13.66%）。各类自然保护地的物种热点区覆盖率不同，风景名胜区类型覆盖率最高（14.74%）。6个物种适宜栖息地的热点区域总面积为280.01km2，保护空缺占热点区域总面积的49.45%，其中密云区、门头沟区和房山区的保护空缺面积最大。基于现有自然保护地体系对野生动物适宜栖息地的保护效率以及存在的空缺，建议因地制宜，采取扩大或合并现有自然保护地、增设新的自然保护地或营造微生境等方式来提升自然保护地的整体保护效率。研究结果可为北京市自然保护地的整合优化提供重要依据，为野生动物重要栖息地的识别与划定提供可行方案，并为加强野生动物的保护管理提供科学指导。 Abstract:Habitats are essential for the survival of wild animals, and clarifying the distribution of a species' suitable habitat can be helpful to strengthen wildlife conservation and to increase the conservation effectiveness for biodiversity. As the capital of China, Beijing holds abundant wild animals and the government has established different types of natural protected areas to provide the refuge for the wildlife. Nowadays, it is urgent to assess the effectiveness of these natural protected areas on the protection of habitats of the wild animals, which will provide scientific guidance to wildlife conservation management and integration of natural protected areas in Beijing. Based on the relative importance and the availability of the distribution data, we selected 6 typical wild animals in Beijing, i.e., Black stork (Ciconia nigra), Brown eared-pheasant (Crossoption mantchuricum), Great bustard (Otis tarda), Mandarin duck (Aix galericulata), Golden eagle (Aquila chrysaetos) and Chinese goral (Naemorhedus griseus), and collected the distribution data of these species through field investigations, open databases and literature. We then analyzed the suitable habitats using the MaxEnt model and spatial analysis function of ArcGIS. We also identified the hotspots and GAPs (GAP analysis) of these species' suitable habitats in Beijing. The results indicated that the natural protected areas covered various proportions of these animals' suitable habitats with a range from 13.66% (Mandarin duck) to 92.82% (Brown-eared pheasant). The total area of the suitable habitat hotspots was 280.01 km2, and mainly distributed in Miyun District, Yanqing District, Mentougou District and Fangshan District. However, the coverage of species hotspots differed among different natural protected areas, with it being highest in scenic spots (14.74%). The GAPs were responsible for 49.45% of the hotspots and mainly distributed in Miyun District, Mentougou District, Fangshan District, and the border of Miyun, Huairou and Yanqing. In particular, Miyun District, Mentougou District and Fangshan District held the largest areas of GAPs. Based on the distribution of the suitable habitats and the protection gaps, it is suggested to take suitable measures to improve the conservation effectiveness of the natural protected areas according to the local circumstances, and adopt different protection strategies for different protection objects, including expanding or merging some natural protected areas, establishing new natural protected areas, and creating micro-habitats. Our study provides feasible solutions for the identification and delineation of important wildlife habitats in Beijing, provides some scientific guidelines for the wildlife management and integration and optimization of the natural protected area system. 参考文献 相似文献 引证文献

ABSTRACTRecent national interest in golden eagle (Aquila chrysaetos) conservation and wind energy development prompted us to investigate golden eagle home range and resource use in the Columbia Plateau Ecoregion (CPE) in Washington and Oregon. From 2004 to 2013, we deployed satellite transmitters on adult eagles (n = 17) and monitored their movements for up to 7 years. We used the Brownian bridge movement model (BBMM) to estimate range characteristics from global position system (GPS) fixes and flight paths of 10 eagles, and modeled resource selection probability functions (RSPFs). Multi‐year home ranges of resident eagles were large (99% volume contour; , SD = 370.2 km2) but were one‐third the size (, SD = 94.6 km2) and contained half as many contours when defined by 95% isopleths. Annual ranges accounted for 66% of multi‐year range size. During the breeding season (16 Jan–15 Aug), eagles occupied ranges that were less fragmented, about half as large, and largely contained within ranges they used outside the breeding season ( overlap = 82.5%, SD = 19.0). Eagles selected upper slopes, rugged terrain, and ridge tops that appear to reflect underlying influences of prey, deflective wind currents, and proximity to nests. Fix distribution predicted by our resource selection model and that of 4 eagles monitored independently in the CPE were highly correlated (rs = 0.992). Our findings suggest conservative landscape management strategies addressing development in lower‐elevation montane and shrub‐steppe/grassland ecosystems can best define golden eagle ranges using exclusive 12.8‐km buffers around nests. Less conservative strategies based on 9.6‐km buffers must include identification and management of upper slopes, ridge‐tops, and areas of varied terrain defined by predictive models or GPS telemetry. For both strategies, high, year‐round intensity of eagle flight and perch use within 50% volume contours (average 3.2 km from nests) due to nest centricity may dramatically increase the probability of eagle conflict with wind turbines in core areas as evidenced by eagle turbine strikes that studies have documented within and beyond this zone. © 2014 The Wildlife Society.

Rapid loss of native shrubs and expansion of invasive annuals like cheatgrass (Bromus tectorum) have extensively altered shrub-steppe systems. Vegetation changes can have bottom-up effects on trophic interactions and ecosystem dynamics. Predators, like Golden Eagles (Aquila chrysaetos) that forage on shrub-reliant prey, may increase their territory size to cope with degraded habitat or abandon historically occupied territories. We used a multi-season occupancy model that accounted for imperfect detection to investigate the associations between landscape cover (i.e., shrub and annual herbaceous), fire history, neighbor density, and territory occupancy of 36 Golden Eagle nesting territories in the Morley Nelson Snake River Birds of Prey National Conservation Area (NCA), Idaho, USA from 1986–2022. The probability of Golden Eagle occupancy decreased 23 % from 0.82 in 1986 to 0.59 in 2022. Further, once territories became vacant, they tended to remain vacant, suggesting that the territories were no longer suitable for eagles or no new eagles were recruiting into the population. Territory occupancy was negatively associated with annual herbaceous cover (β: -0.86, 95% CI: -1.53 to -0.24) and tended to be positively associated with shrub cover (β: 0.63, 95% CI: -0.11 to 1.39) and time since last burn (β: 0.25, 95% CI: -0.28 to 0.83). Territories that were farther from other occupied territories had a higher probability of occupancy than territories with closer neighbors (β: -3.56, 95% CI: -4.22 to -2.92), likely because as habitat degraded, eagles compensated by expanding their territories into nearby vacant territories. The probability of detection was high at 0.90 but improved in surveys conducted earlier in the day and later in the breeding season. Together, these results show that landscape change and habitat degradation have bottom-up effects on Golden Eagle behavior and territory occupancy, resulting in an overall decrease in the local carrying capacity for eagles. Understanding associations between environmental change and territory occupancy has important implications for predicting population persistence and eagle adaptability to changing landscapes.

During a five‐year period, 1975–1979, a total of 2881 prey individuals of 65 prey species were collected at 162 golden eagle nests from northern Sweden and from the island of Gotland. In northern Sweden birds are taken in higher numbers than mammals but calculated as weight the two categories are of equal importance, The main prey during the breeding season are capercaillie, black grouse, willow grouse, ptarmigan, mountain hare and reindeer fawns which together form 91% of the total food biomass. The capercaillie and the black grouse are taken more in the southern part of the coniferous region than in the northern. In contrast, in northern areas, reindeer fawns are more preyed upon than in the South, Ptarmigan and willow grouse are the most commonly captured prey species in mountain areas. The total number of reindeer fawns taken (dead and/or alive) by the Swedish golden eagle population during one summer is estimated at 600 individuals. On Gotland the golden eagles take mammals more often than in its northern distribution area. Rabbit and hedgehog arc the most important species.

Capsule Home-range of resident pairs of Golden Eagle was usually smaller during a successful breeding season than during winter and during an unsuccessful breeding season. Aims To examine how Golden Eagles use space around their nests with respect to season and breeding status, and to compare home-range-use between a high and a low density region. Methods Nine adults in six mainland Argyll ranges were radiotracked between 1991 and 1996. On the island of Mull visual observations of range-use were obtained for five ranges between 1994 and 1998. Results Overall, Mull ranges were smaller than the Argyll ranges, reflecting the much higher range density on Mull. In both regions there were significant differences between ranging distances with season and breeding status. In general, ranging distances were smallest during breeding seasons when young were fledged. Conclusions Studies of range-use in Golden Eagles must be conducted across a 12-month period, as a minimum.

Wind and other energy development are expanding rapidly and on an unprecedented scale within the range of the Golden Eagle (Aquila chrysaetos) while other anthropogenic-related changes, wildfires, invasive plants, drought, and climate change are altering or destroying native habitats occupied by Golden Eagles. However, the potential effects of these factors on North American Golden Eagle populations are largely unknown and the most recent evidence indicates that the population in the western United States is declining slightly. Impediments to evaluating the potential effects of energy development projects on wintering Golden Eagles include issues of scale and a paucity of available information about eagle winter use areas and ecology. We applied a predictive model of eagle winter distribution developed for Idaho and Montana, to Idaho, Utah, Nevada and eastern Oregon to help identify potential wintering areas and identify risks that occur in those areas. The model identifies ~40% of the four state study area as potentially suitable eagle winter habitat and provides a basis for spatial assessment of possible risk factors to eagles wintering there. We used eBird and Christmas Bird Count citizen science datasets for an independent evaluation of the accuracy of our predictive distribution model. The model was robust, accurately predicting the presence of wintering Golden Eagles significantly more often than expected. We used digital environmental datasets (layers) of potential risk factors, in conjunction with model predicted eagle distribution, to better understand and estimate the extent of risks to the wintering eagle population in the study area. These layers represent available data for some of the factors previously identified as risks in the landscape to wintering Golden Eagles. The majority of predicted eagle wintering areas occurred where there was little habitat fragmentation (<10%). All predicted winter areas contained at least one potential risk factor (e.g., potential for energy development); 39.4% of predicted winter areas contained at least two known risk factors. The greatest number of risks often occurred where the human footprint was highest and where eagles were less likely to occur during winter. Our results can be used to help prioritize field surveys for identifying important Golden Eagle winter areas in the western United States and determine potential locations where energy development is least likely to have negative effects on wintering eagles. Survey efforts can be allocated in consideration of management and conservation objectives based on predicted habitat suitability and risk factors. For example, surveys for areas of high suitability and low risk can identify places to focus management for conservation of eagle winter areas. Further, sites proposed for wind energy development could be reviewed initially based on model predicted eagle wintering areas and then surveyed to determine if permitting for development is appropriate.

Recently, there has been an increase in concern for Golden Eagle populations in the western United States, stemming from a marked decrease in the number of migrants and an increase in future threats from a variety of factors including, but not limited to, energy development. Part of an effective conservation strategy for Golden Eagles involves understanding basic requirements of the eagles during both the breeding and nonbreeding seasons. We used PTT and GPS/PTT transmitter data from 14 adult, migratory Golden Eagles captured near the Rocky Mountain Front in Montana to determine the location and size of winter ranges and habitat use and selection within chosen winter ranges. We found large variability in location and size of winter ranges in the western United States. Eagles showed high fidelity to core wintering areas but plasticity in annual range sizes. Adult, migrant Golden Eagles used habitat types associated with perches and primary prey species. Golden Eagles chose areas within winter rang...

The Golden Eagle (Aquila chrysaetos) has one of the largest distributions of all eagles. The subspecies Aquila chrysaetos homeyeri occurs in the Republic of Armenia, country in the South Caucasus region, where it is recognized as a year-round resident and included in the Red Book of Animals of The Republic of Armenia as a “Vulnerable” (VU D1) species. However, in Armenia the state of the species population and abundance has been studied extremely poorly, which makes it difficult to organize its effective conservation without trustworthy data. There is only fragmentary, scattered information about the finds of nest sites or only about the locations where individuals were observed. In the 1990’s, in the South Caucasus, at least 75–100 breeding pairs were known, nevertheless, there is no exact data on Golden Eagles in Armenia. Various estimations were done for the species in the early 2000’s, varying between 20–80 breeding pairs. According to the Red Book of Animals of RA, published in 2010, the population of the Golden Eagle consists of 34–38 breeding pairs. Additionally, during our recent sporadic field studies of raptor species we did not observe nesting activities in many previously known Golden Eagle breeding territories. Hence, in order to understand the status and to clarify all the uncertainties, in 2023 we began targeted research on the Golden Eagle breeding population in the Republic of Armenia. During the short period, lasting from early March to mid-July, we managed to study most of suitable breeding habitats in Ararat, Vayots dzor, and Lori regions, and parts of Tavush, Kotayq, Shirak, and Aragatsotn regions (seven out of ten regions of RA). Following our study design, we checked known literature data in the field and reported breeding territories, as well as suitable habitats derived from preliminary GIS modelling. In the field we used 20–60×60 spotting scopes, 10×42 binoculars, and drone. According to preliminary results, during the first year of studies, only four confirmed active nests were located, of which three pairs had successful breeding (three nestlings fledged in the beginning of July), and one nest probably failed. Additionally, one nest was found renovated with green branches, however, birds were not seen in the nest (one adult bird was observed few kilometers away from the breeding territory). Two nests were located in Vayots dzor region, one in Ararat region, and one in Lori region. In addition, 19 non-occupied nests were found, mainly at a large distance from found active nests. Eleven non-occupied nests were found in Vayots dzor region, three in Lori region, two in Kotayk region, two in Ararat region, and finally one in Shirak region. Almost all abandoned nests were located in areas with various extent of anthropogenic activity (roads, pastures, settlements, etc.). The ongoing project is carried out in the framework of the project “Birds of prey research and conservation” of the branch of German Nature Protection Union (NABU) in the Republic of Armenia.

Supplementary food resources (e.g., subsidies) associated with agriculture can benefit wildlife species, increasing predictability and availability of food. Avian scavengers including raptors often utilize subsidies associated with both recreational hunting and pest shooting on agricultural lands. However, these subsidies can contain lead (Pb) fragments if they are culled with Pb‐based ammunition, potentially leading to Pb poisoning and physiological impairment in wildlife. Nesting Golden Eagles (Aquila chrysaetos) commonly forage in agricultural lands during the breeding season, and therefore, both adults and their nestlings are susceptible to Pb exposure from scavenging shot wildlife. We assessed drivers of Pb exposure in 258 nestling Golden Eagles (401 total blood samples), along with physiological and growth responses, in agricultural lands across four western states in the United States. We also evaluated the birds’ Pb stable isotope signatures to inform exposure sources. Twenty‐six percent of Golden Eagle nestlings contained Pb concentrations associated with subclinical poisoning for sensitive species (0.03–0.2 μg/g ww), 4% had Pb concentrations that exceeded subclinical poisoning benchmarks (0.2–0.5 μg/g ww), and &lt;1% exceeded either concentrations associated with clinical poisoning (0.5–1.0 μg/g ww) and or those deemed to cause severe clinical poisoning (&gt;1.0 μg/g ww). Lead concentrations were highest in nestlings with close proximity to fields that potentially provided subsidies and declined exponentially as distance to subsidies increased. However, close proximity to agriculture, and presumably subsidies, positively influenced nestling growth rates. Across the range of Pb exposure, nestlings experienced a 67% reduction in delta‐aminolevulinic acid dehydratase (δ‐ALAD) activity, suggesting nestlings may have been anemic or experiencing cellular damage. Isotopic ratios of 206Pb/207Pb increased non‐linearly with increasing blood Pb in Golden Eagle nestlings, and 45% of the birds were consistent with those of ammunition. However, above 0.10 μg/g ww, the proportion associated with ammunition increased to 89% of the nestlings. An improved understanding of how these positive (growth) and negative (physiology) effects associated with proximity to subsidies interact would be beneficial to managers when considering management scenarios and potentially evaluating any measures taken to reduce Pb exposure across the landscape.

Golden Eagles are resident in Greece and known to feed mainly on tortoises when breeding. However, information on alternative prey is scarce, especially during the tortoise brumation, that roughly coincides with the eagles’ non-breeding season. We analyzed 827 prey items collected from 12 territories over five territory years and 84 records of eagles hunting or feeding behavior. Tortoises dominated the breeding season diet (71% of prey categories on average) and over half of all hunting/feeding observations. While no spatial structure was evident, habitat variables such as forest canopy cover were important associates in golden eagle diet seasonally. A significant seasonal pattern emerged in diet diversity, using a subset of six territories with at least 10 samples per season. Eagles shifted from a narrow, reptile- based breeding season diet dominated by tortoises to a broader non-breeding season diet, that included more carrion, mammals and birds. Breeding season specialization on ectothermic prey is a trait usually associated with migratory raptors in the Western Palearctic. The observed dietary diversity expansion accompanied by residency in the absence of ectothermic prey, highlights the adaptability of the golden eagle, a generalist predator. Tortoise populations in Greece are of conservation concern and land use changes as well as climate change, such as development and land abandonment may increase the prevalence of catastrophic megafires, exacerbating the threats to the golden eagle’s main prey when breeding. We discuss this and other diet related conservation implications for the species in northern Greece.