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Roughly one-third of all eagle species are considered to be threatened or endangered, but the ecology of most eagles remains poorly understood. While the pronounced territoriality of breeding adults facilitates behavioral studies, the demography of non-breeding individuals (pre-adults and non-territorial floaters) is almost completely unknown. Traditionally, limited data on pre-adult and floater movement come from wing-tagging and/or telemetry studies. As an alternative to these methods we used genetic analyses of non-invasively collected feathers to investigate the population biology of non-breeding eastern imperial eagles (Aquila heliaca) in Kazakhstan. Microsatellite profiles of shed feathers indicate that eastern imperial eagles roost communally with other raptors. Furthermore, roosts are large and dynamic: 287 non-breeding eastern imperial eagles were detected in our sample, and a mark-recapture analysis estimated the total number to be 308 ± 8. The natal origins of these individuals were investigated by comparing their microsatellite profiles to those available for >90% of the eastern imperial eagle chicks hatched at the study site over the six previous breeding seasons. Only 4% of the individuals genetically matched a chick, suggesting that the reserve may serve as a critical refugium for pre-adults and itinerant floaters. Feathers have long been recognized as a suitable source of DNA, but few studies have used wide-scale, non-invasive collections of feathers (>1,000 samples) to investigate fundamental aspects of avian biology. Our research demonstrates that non-invasive genetic analyses of feathers can be used to evaluate population size, natal philopatry, and local movements of birds that are difficult to study using traditional means.

Behavior of young birds can have important consequences for population dynamics. We investigated the autumnal post-fledging movements of 3 White-tailed Sea Eagles (Haliaeetus albicilla) hatched in Kazakhstan. All 3 eagles traveled south, flying on average 25–108 km/d. Movement was nonrandom, with eagles generally traveling near mosaics of forest, open areas, and water, and rarely using areas with little vegetation. As the first study of movements of White-tailed Sea Eagles in arid Central Asia, this study provides insight into potential limiting factors and how these birds interact with their environment during long-distance movements.

We evaluated factors that permit species coexistence in an exceptional assemblage of similar raptor species at the Naurzum Zapovednik (a national nature reserve) in north-central Kazakhstan. White-tailed Sea-Eagle (Haliaeetus albicilla), Imperial Eagle (Aquila heliaca), Golden Eagle (A. chrysaetos), and Steppe Eagle (A. nipalensis) all breed at the Zapovednik. Steppe Eagle use of nesting resources was distinct from that of tree-nesting species. We evaluated differences in nest tree and nest habitat characteristics, nest dimensions and positions, and nest spacing among the three forest-dwelling eagle species to distinguish between the effects of inter- and intraspecific resource limitations on species coexistence. Although the different species bred in similar habitat and sometimes reused other species' nests, the dimensions, positions and locations of their nests often differed. These differences did not appear to result from interspecific competition. Nest spacing trends were also species specific; Imperial Eagles generally nested farther from other eagle nests than did Golden Eagles and White-tailed Sea-Eagles. Intraspecific variation in habitat, physical characteristics, and spacing patterns of Imperial Eagle nests was extensive throughout the nature reserve. Although interspecific partitioning of nesting habitat may allow coexistence of ground-nesting Steppe Eagles, interspecific competition did not appear to be a primary determinant of the use of nest habitat, space, or nests by tree-nesting species. Rather, interspecific effects appeared secondary to intraspecific effects in determining coexistence of tree-nesting eagles at this site. Coexistencia en una Asamblea Multiespecífica de Águilas en Asia Central Resumen. Evaluamos los factores que permiten la coexistencia de varias especies de aves rapaces similares en Naurzum Zapovednik, una reserva natural nacional, en la región norcentral de Kazakhstan. Las águilas Haliaeetus albicilla, Aquila heliaca, A. chrysaetos y A. nipalensis se reproducen en Zapovednik. El uso de los recursos de nidificación por A. nipalensis fue diferente al de las otras especies, las cuales nidifican en árboles. Evaluamos las diferencias en los árboles y características de los hábitats de nidificación y las dimensiones, posición y distribución de los nidos entre las tres especies de águilas que habitan ambientes boscosos, para distinguir entre los efectos de limitación por recursos a nivel interespecífico e intraespecífico sobre la coexistencia de estas especies. A pesar de que las diferentes especies se reprodujeron en hábitats similares y a veces reutilizaron los nidos de otras especies, las dimensiones, posiciones y localizaciones de sus nidos difirieron a menudo. Estas diferencias no parecen ser un resultado de competencia interespecífica. Las tendencias de la distribución en el espacio de los nidos también fueron especie-específicas; Las águilas de la especie A. heliaca nidificaron generalmente más alejadas de nidos de las otras especies que las águilas H. albicilla y A. chrysaetos. La variación intraespecífica en el hábitat, características físicas y patrones de distribución de A. heliaca fue considerable a través de la reserva natural. A pesar de que la partición interespecífica del hábitat de nidificación podría permitir la coexistencia de la especie A. nipalensis (la cual nidifica sobre el suelo), la competencia interespecífica no pareció ser importante en determinar el uso del hábitat de nidificación, de los nidos o su distribución para las especies de águilas que nidifican en árboles. En cambio, los efectos interespecíficos parecieron ser secundarios con relación a los efectos intraespecífcos en determinar la coexistencia de las águilas que nidifican en árboles en este sitio.

We evaluated the relationship between spatial variability in prey and food habits of eastern imperial eagles Aquila heliaca at a 90,000 ha national nature reserve in north-central Kazakhstan. Eagle diet varied greatly within the population and the spatial structure of eagle diet within the population varied according to the scale of measurement. Patterns in dietary response were inconsistent with expectations if either ontogenetic imprinting or competition determined diet choice, but they met expectations if functional response determined diet. Eagles nesting near a high-density prey resource used that resource almost exclusively. In contrast, in locations with no single high-density prey species, eagles' diet was more diverse. Our results demonstrate that spatial structuring of diet of vertebrate predators can provide important insight into the mechanisms that drive dietary decisions.

Behavior of young birds can have important consequences for population dynamics. We investigated the autumnal post-fledging movements of 3 White-tailed Sea Eagles (Haliaeetus albicilla) hatched in Kazakhstan. All 3 eagles traveled south, flying on average 25-108 km/d. Movement was nonrandom, with eagles generally traveling near mosaics of forest, open areas, and water, and rarely using areas with little vegetation. As the first study of movements of White-tailed Sea Eagles in arid Central Asia, this study provides insight into potential limiting factors and how these birds interact with their environment during long-distance movements. Received 7 April 2017. Accepted 30 August 2017. Key words: habitat associations, hatch-year birds, Kazakhstan, long-distance movements, telemetry. El comportamiento de las aves jovenes puede tener consecuencias importantes en dinamicas poblacionalcs. Investigamos los movimientos posemancipaci[eth]n otonal de tres aguilas Haliaeetus albicilla que eclosionaron en Kazajistan. Todas las aguilas volaron hacia el sur, volando entre 25-108 km/d. Estos movimientos fueron no-aleatorios, en los que las aguilas generalmente viajaban cerca de mosaicos dc bosque, areas abiertas y agua, y raramente usando areas con poca vegetation. Como primer estudio de los movimientos de estas aguilas en la arida region central de Asia, este estudio provee ideas en los posibles factores limitantes y como estas aves interactuan con su ambiente durante movimientos dc larga distancia. Palabras clave: asociaciones de habitat, aves del primer ano, Kazajistan, movimientos de larga distancia, telemetria.

Backpack radio-tags can be used to monitor survival of raptors for several years after fledging, but may reduce survival if a poor fit results from subjective judgments. We present an attachment method that can use bird measurements to predict harness sizes. Relationships between body mass of Saker Falcons and harness size predicted the size for smaller falcon species. Harnesses were fitted when birds had reached full size in the nest, which required age estimation at a previous visit to predict a fledging date. Equations based on wing length provided objective aging of nestlings. A pump-pressured water gun aided capture of young falcons and toggle-loops restrained the feet during marking. Saker Falcons with radio-tags and others marked only with leg bands and implanted transponders had the same recapture rate (7%) in autumn, indicating similar survival. This retrap rate should be adequate to estimate harvest rates and population sizes for Saker Falcons.

We evaluated factors that permit species coexistence in an exceptional assemblage of similar raptor species at the Naurzum Zapovednik (a national nature reserve) in north-central Kazakhstan. White-tailed Sea-Eagle (Haliaeetus albicilla), Imperial Eagle (Aquila heliaca), Golden Eagle (A. chrysaetos), and Steppe Eagle (A. nipalensis) all breed at the Zapovednik. Steppe Eagle use of nesting resources was distinct from that of tree-nesting species. We evaluated differences in nest tree and nest habitat characteristics, nest dimensions and positions, and nest spacing among the three forest-dwelling eagle species to distinguish between the effects of inter- and intraspecific resource limitations on species coexistence. Although the different species bred in similar habitat and sometimes reused other species' nests, the dimensions, positions and locations of their nests often differed. These differences did not appear to result from interspecific competition. Nest spacing trends were also species specific; Imperial Eagles generally nested farther from other eagle nests than did Golden Eagles and White-tailed Sea-Eagles. Intraspecific variation in habitat, physical characteristics, and spacing patterns of Imperial Eagle nests was extensive throughout the nature reserve. Although interspecific partitioning of nesting habitat may allow coexistence of ground-nesting Steppe Eagles, interspecific competition did not appear to be a primary determinant of the use of nest habitat, space, or nests by tree-nesting species. Rather, interspecific effects appeared secondary to intraspecific effects in determining coexistence of tree-nesting eagles at this site. Coexistencia en una Asamblea Multiespecífica de Águilas en Asia Central Resumen. Evaluamos los factores que permiten la coexistencia de varias especies de aves rapaces similares en Naurzum Zapovednik, una reserva natural nacional, en la región norcentral de Kazakhstan. Las águilas Haliaeetus albicilla, Aquila heliaca, A. chrysaetos y A. nipalensis se reproducen en Zapovednik. El uso de los recursos de nidificación por A. nipalensis fue diferente al de las otras especies, las cuales nidifican en árboles. Evaluamos las diferencias en los árboles y características de los hábitats de nidificación y las dimensiones, posición y distribución de los nidos entre las tres especies de águilas que habitan ambientes boscosos, para distinguir entre los efectos de limitación por recursos a nivel interespecífico e intraespecífico sobre la coexistencia de estas especies. A pesar de que las diferentes especies se reprodujeron en hábitats similares y a veces reutilizaron los nidos de otras especies, las dimensiones, posiciones y localizaciones de sus nidos difirieron a menudo. Estas diferencias no parecen ser un resultado de competencia interespecífica. Las tendencias de la distribución en el espacio de los nidos también fueron especie-específicas; Las águilas de la especie A. heliaca nidificaron generalmente más alejadas de nidos de las otras especies que las águilas H. albicilla y A. chrysaetos. La variación intraespecífica en el hábitat, características físicas y patrones de distribución de A. heliaca fue considerable a través de la reserva natural. A pesar de que la partición interespecífica del hábitat de nidificación podría permitir la coexistencia de la especie A. nipalensis (la cual nidifica sobre el suelo), la competencia interespecífica no pareció ser importante en determinar el uso del hábitat de nidificación, de los nidos o su distribución para las especies de águilas que nidifican en árboles. En cambio, los efectos interespecíficos parecieron ser secundarios con relación a los efectos intraespecífcos en determinar la coexistencia de las águilas que nidifican en árboles en este sitio.

Historically Russia and Great Britain squared off here fighting their ''great game'' of imperial conquest; more recently it has been a launch pad of global terrorism and the epicenter of the US government's ''war on terror.'' Because the region is so important for so many reasons, and because, during Soviet times, it was largely inaccessible to westerners, there is a growing interest in the area, its culture and its natural history. Central Asia is also rich in its avifauna and, until now, depauperate in bird guides. Because of its geographic enormity, the variety of its landscapes and the difficulties (for foreigners) of accessing Russian-language literature, it is no mean feat to assemble authoritative information on central Asian flora and fauna.

Backpack radio-tags can be used to monitor survival of raptors for several years after fledging, but may reduce survival if a poor fit results from subjective judgments. We present an attachment method that can use bird measurements to predict harness sizes. Relationships between body mass of Saker Falcons and harness size predicted the size for smaller falcon species. Harnesses were fitted when birds had reached full size in the nest, which required age estimation at a previous visit to predict a fledging date. Equations based on wing length provided objective aging of nestlings. A pump-pressured water gun aided capture of young falcons and toggle-loops restrained the feet during marking. Saker Falcons with radio-tags and others marked only with leg bands and implanted transponders had the same recapture rate (7%) in autumn, indicating similar survival. This retrap rate should be adequate to estimate harvest rates and population sizes for Saker Falcons.

This is the first study of cataract incidence in a cohort of Mayak Production Association workers first employed at one of the main facilities in 1948-1982 and followed up till the end of 2008 (22,377 workers). Principal advantages of the study are the large size of the cohort, long-term follow-up and sufficient statistical power, available results of annual eye examinations over the entire follow-up period and detailed information on non-radiation confounders. Individual measured doses from external γ-rays and neutrons used in the analyses were provided by the Mayak Worker Dosimetry System 2008 (MWDS-2008). Relative risk (RR) and excess relative risk (ERR) per unit dose (Gy) were calculated based on maximum likelihood using the AMFIT module of the EPICURE software. The RR of cataract incidence was found to be the highest in workers exposed at doses above 2.0 Gy. A significant linear association of cataract incidence with cumulative dose from external γ-rays was found with ERR/Gy equal to 0.28 (95% confidence intervals: 0.20, 0.37). The results obtained varied slightly with inclusion of additional adjustments for non-radiation factors (smoking index, hypertension, glaucoma and body mass index). Adjusting for the dose from neutrons gave a considerable increase in ERR/Gy for cataract incidence.