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Cliff‐nesting raptors present considerable challenges for population estimation due to their sparse distribution across remote landscapes and the multiple occupancy states (e.g., unoccupied, occupancy without breeding, breeding occupancy) through which we observe their nesting territory dynamics. To increase the efficiency and spatial inference of surveys, we developed 2 versions of a multi‐state, time‐removal model: 1 for long‐term monitoring studies and the other for population inventories or single‐season surveys in which there is no prior knowledge of nest locations. We focused our development of these methods in the context of a combined aerial and ground‐based survey approach, which permits efficient surveying at landscape scales. The approach, however, is also applicable to designs restricted to ground surveys. For long‐term monitoring of species with alternative nests, we formulated a version of the model that accounts for state uncertainty at the territory level caused by a failure to observe all nests within a territory. Simulations based on the long‐term monitoring model indicated adequate (near nominal) coverage and low relative bias (<0.05) for nearly all parameters. In the simulation study for the inventory model, population size estimates showed negligible bias for a survey duration of 90 minutes. We applied our approach to a long‐term study of golden eagles (Aquila chrysaetos) in Alaska and demonstrated that the maximum effort spent on any nesting territory could be reduced by up to almost 90% of that recommended by standard protocols. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. To increase the efficiency and spatial inference of surveys of cliff‐nesting raptors, we developed 2 versions of a multi‐state, time‐removal model: 1 for long‐term monitoring studies and the other for population inventories. We focused our development of these methods in the context of a combined aerial and ground‐based survey approach and demonstrated that the maximum effort spent on any nesting territory could be reduced by up to almost 90% of that recommended by standard protocols. [ABSTRACT FROM AUTHOR]

Abstract: One of the central goals of the field of population ecology is to identify the drivers of population dynamics, particularly in the context of predator–prey relationships. Understanding the relative role of top‐down versus bottom‐up drivers is of particular interest in understanding ecosystem dynamics. Our goal was to explore predator–prey relationships in a boreal ecosystem in interior Alaska through the use of multispecies long‐term monitoring data. We used 29 years of field data and a dynamic multistate site occupancy modeling approach to explore the trophic relationships between an apex predator, the golden eagle, and cyclic populations of the two primary prey species available to eagles early in the breeding season, snowshoe hare and willow ptarmigan. We found that golden eagle reproductive success was reliant on prey numbers, but also responded prior to changes in the phase of the snowshoe hare population cycle and failed to respond to variation in hare cycle amplitude. There was no lagged response to ptarmigan populations, and ptarmigan populations recovered quickly from the low phase. Together, these results suggested that eagle reproduction is largely driven by bottom‐up processes, with little evidence of top‐down control of either ptarmigan or hare populations. Although the relationship between golden eagle reproductive success and prey abundance had been previously established, here we established prey populations are likely driving eagle dynamics through bottom‐up processes. The key to this insight was our focus on golden eagle reproductive parameters rather than overall abundance. Although our inference is limited to the golden eagle–hare–ptarmigan relationships we studied, our results suggest caution in interpreting predator–prey abundance patterns among other species as strong evidence for top‐down control. [ABSTRACT FROM AUTHOR]

Migratory Golden Eagles ( Aquila chrysaetos) from Alaska winter across a vast region of western North America, much of which is undergoing rapid change from a diversity of indirect and direct human activities. To address recent conservation concerns, we are studying the year-round movements of migratory Golden Eagles from interior and northern Alaska to identify and evaluate potential risks to their survival. We are also developing new survey techniques to estimate population size and trends. As part of our ongoing studies, we observed migrating Golden Eagles in spring and autumn 2014 during field investigations to locate Golden Eagle capture sites in eastern interior Alaska, and in spring 2015 during capture activities. We observed large numbers of Golden Eagles in both spring and autumn, suggesting that the Mentasta Mountains are an important migration corridor for this species. Further, our observations, including 1364 migrating Golden Eagles in October 2014, suggested that the Alaska Golden Eagle population is much larger than is reflected in the only currently available statewide population estimate of 2400 eagles. In combination with historical and contemporary tracking studies, our observations in the Mentasta Mountains provide important new information about Golden Eagle migration in Alaska and stimulate interest in answering fundamental questions about using counts of migrating Golden Eagles to estimate, and detect change in, the population size of Alaska's migratory Golden Eagles. Our observations also provide new information about Rough-legged Hawk migration in Alaska. Los ejemplares migratorios de Aquila chrysaetos provenientes de Alaska invernan a lo largo de una amplia región del oeste de América del Norte, gran parte de la cual está siendo sometida a un cambio rápido ocasionado por una diversidad de actividades humanas directas e indirectas. Para abordar preocupaciones de conservación recientes, estamos estudiando, a lo largo del año, los movimientos de ejemplares migratorios de A. chrysaetos provenientes del interior continental y del norte de Alaska para identificar y evaluar riesgos potenciales para su supervivencia. También estamos desarrollando nuevas técnicas de muestreo para estimar el tamaño y las tendencias poblacionales. Como parte de nuestros estudios en curso, observamos ejemplares migratorios de A. chrysaetos en primavera y otoño de 2014 durante investigaciones de campo para ubicar lugares de captura en el este continental de Alaska, y en primavera de 2015 durante las actividades de captura. Observamos gran número de ejemplares de A. chrysaetos tanto en primavera como en otoño, lo que sugiere que las montañas Mentasta son un importante corredor migratorio para esta especie. Además, nuestras observaciones, que contabilizaron 1364 ejemplares migratorios de A. chrysaetos, sugieren que la población de esta especie en Alaska es mucho mayor que la documentada en la única estimación poblacional estatal disponible de 2400 águilas. En combinación con estudios de seguimiento históricos y contemporáneos, nuestras observaciones en las Montañas Mentasta proporcionan información nueva e importante sobre la migración de esta especie de águila en Alaska y despiertan interés en dar respuesta a preguntas fundamentales acerca del uso de conteos de ejemplares migratorios de A. chrysaetos para estimar y detectar cambios en el tamaño poblacional de esta especie. Nuestras observaciones también proporcionan nueva información acerca de la migración de Buteo lagopus en Alaska. [Traducción del equipo editorial] [ABSTRACT FROM AUTHOR]

The article presents the result of monitoring conducted on nests built by Golden eagle, Aquila chrysaetos, at Denali National Park and Preserve in Alaska. The observation includes territory occupancy and breeding activities of the eagle, rate of nesting success and production. The types of tree and plant branches used, the estimated age of the nests and the relations of egg with the nest are also monitored.

Abstract: A primary objective of ecological monitoring programs typically includes the efficient detection of population trends. Passerines as a group are important ecological indicators and are often included in such programs to provide information on multiple species with a single survey technique. However, commonly used field and analytical approaches may not provide appropriate inference or sensitivity due to assumption violations and differences in the proportion of the population exposed to sampling. Recent methodological developments utilizing repeated point counts and an N-mixture modeling approach for analysis may produce more consistent and interpretable estimates applicable to the superpopulation of individuals using a site during the breeding season. These estimates should be more useful for monitoring because they are not conditioned on presence or availability as are most single-visit approaches. We used repeated count data collected in Denali National Park and Preserve, Alaska (Denali) between 1995 and 2009 from 12 common passerine species to assess variation in presence and availability throughout the season, estimate trends in superpopulation abundance, and provide recommendations for the design of future monitoring programs. We found that variation in detection due to presence and availability was large and differed among species. After accounting for these sources of variation, we estimated abundance of Wilson’s warblers (Wilsonia pusilla) had declined by approximately 48% and fox sparrow (Passerella iliaca) abundance had increased by approximately 250% over 15years. Combined, our results suggest that if trend estimation is a priority, passerine monitoring programs should formally address all components of the detection process, including the probabilities of presence and availability. [Copyright &y& Elsevier]

This article presents a study which compared the sources of mortality and wintering ranges of Golden Eagles from Denali National Park in Alaska. For the study researchers utilized banding and satellite telemetry data on the movements and survival of migratory birds. They discovered that electrocution, shooting and starvation are the most common causes of death of migratory eagles. They also discovered that the locations of banded eagles encountered in winter ranged from southern Alberta to north-central Mexico.

Abstract: The recent development of multistate site occupancy models offers great opportunities to frame and solve decision problems for conservation that can be viewed in terms of site occupancy. These models have several characteristics (e.g., they account for detectability) that make them particularly well suited for addressing management and conservation problems. We applied multistate site occupancy models to evaluate hypotheses related to the conservation and management of Golden Eagles (Aquila chrysaetos) in Denali National Park, Alaska, and provided estimates of transition probabilities among three occupancy states for nesting areas (occupied with successful reproduction, occupied with unsuccessful reproduction, and unoccupied). Our estimation models included the effect of potential recreational activities (hikers) and environmental covariates such as a snowshoe hare (Lepus americanus) index on transition probabilities among the three occupancy states. Based on the most parsimonious model, support for the hypothesis of an effect of potential human disturbance on site occupancy dynamics was equivocal. There was some evidence that potential human disturbance negatively affected local colonization of territories, but there was no evidence of an effect on reproductive performance parameters. In addition, models that assume a positive relationship between the hare index and successful reproduction were well supported by the data. The statistical approach that we used is particularly useful to parameterize management models that can then be used to make optimal decisions related to the management of Golden Eagles in Denali. Although in our case we were particularly interested in managing recreational activities, we believe that such models should be useful to for a broad class of management and conservation problems. [Copyright &y& Elsevier]

The article provides information on the characteristics, features and behavior of raptors. Most often, raptors travel thousands of long distances right from the very moment they leave their natal places until the time they enter breeding population. Meanwhile, the author emphasizes that the movement of raptors can be too dependent on the factors that influence their survival. In addition, the natal origins of juvenile Glrfalcons are unknown yet they are mostly observed during their breeding range.

The article discusses the results of a study on the year-round movements of two cohorts of juvenile Golden Eagles from Denali National Park and Preserve in Alaska. The study found that the eagles exhibited little fidelity to their autumn migration paths as they migrated northwest in spring through western Canada and into Alaska. Cumulative tracking distances were high during spring migration reaching a peak of 284 filometer (km) a day in 1998 and 330 km a day in 2000.

The postfledging dependence period is not well documented for many species of raptors, including Golden Eagles (Aquila chrysaetos). From 1997 to 1999, we used satellite telemetry to estimate the length of the postfledging dependence period, and the finite survival rate of fledglings during that period, for migratory Golden Eagles in Denali National Park and Preserve, Alaska. Length of the postfledging dependence period averaged 50.1 days and ranged from 39 to 63 days. The postfledging dependence period was longer for Golden Eagles that hatched earlier, but hatching date did not influence the date they departed their natal area. Average date of departure from the natal area was 25 September. The departure period spanned a 17-day period from 15 September to 5 October, and coincided with a series of environmental changes including decreases in day length, temperature, and prey diversity. Probability of survival during the postfledging dependence period was 0.98 (95% IC = 0.94 to 1.00). [ABSTRACT FROM AUTHOR]

The conservation of golden eagles (Aquila chrysaetos) requires a thorough understanding of their demographic parameters. Productivity, commonly measured as the number of nestlings or fledglings per pair, is the parameter reported by most studies of nesting golden eagles and is often used as a measure of their population status. Survival may be an equally or more important parameter to measure; however, survival rates of golden eagles are not well documented. We used satellite telemetry to estimate the probability of first-year survival for migratory golden eagles raised in Denali National Park and Preserve, Alaska, USA. We calculated the probability of first-year survival using program MARK. Based on the best approximating model, monthly survival probability was 0.88 ± 0.04 (mean ± SE) during the autumn migration and early winter period for golden eagles marked in 1997 and 0. 78 ± 0.05 during the same period for golden eagles marked in 1999. Monthly survival during the remaining 3 periods (i.e., late winter, spring migration, summer) was 0.94 ± 0.03 for both cohorts. Survival during the entire 11- month period was 0.34 ± 0. 10 for the 1997 cohort and 0. 19 ± 0.07 for the 1999 cohort. Causes of mortality included starvation, electrocution, and poaching. Our results indicate that low first-year survival may limit recruitment and we recommend that golden eagle monitoring programs include survival estimates. [ABSTRACT FROM AUTHOR]

A recent summary of raptor migration count data concluded that the status of Golden Eagles (Aquila chrysaetos) in western North America warranted concern (Hoffman and Smith 2003). Our analysis of these data did not lead us to the same conclusion. We have three specific concerns. First, the regional characterizations of eagle migration in Hoffman and Smith (2003) are based on a very small sample of sites. Therefore, we recommend that these characterizations be considered as hypothetical in nature. Second, we suggest that the population cycles and patterns of age-specific population change described by Hoffman and Smith (2003) are neither as general nor as clear-cut as they indicated. Finally, although the authors expressed concern about the status of Golden Eagles based upon both their findings and data from other sources, we did not find compelling evidence for population declines in our inspection of those same data. [ABSTRACT FROM AUTHOR]

Presents information on a study which described the reproductive characteristics of Golden Eagles breeding in Denali National Park, Alaska during an entire snowshoe hare cycle, 1988-1997. Methodology; Results and discussion.

Participatory research approaches hold potential to better understand society through valuing lived experience. Formula feeding babies is routinely stigmatised in the UK, despite inadequate support to facilitate breastfeeding. Our community science project investigated the safety of powdered infant formula preparation in the home through the completion of an at-home experiment and a research diary with closed and open questions (n = 151). To add validity to the interpretation of open text data in research diaries, a community analysis group of five formula-feeding mothers was established. The community analysts undertook inductive thematic analysis through a series of analysis group meetings focused around data extracts, contributed to the study's empirical outputs and this methodological output, meeting 23 times over a nine-month period. Detailed notes were taken during meetings and the methodological elements of these were thematically analysed with the community analysts to produce this article, with extracts from the academic researchers' field notes added where relevant. The overarching themes, presenting both positive experiences and areas for improvement, focused on: (i) clarity of expectations and the impact this had on community analysts' confidence, (ii) the stigmatising topic area and how this was managed by the facilitators, and (iii) feeling valued, in relation to honoraria, inclusion in outputs and community analysts coming to recognise their own expertise. Furthermore, the community analysts co-produced recommendations for including community analysts in future research. It provides guidance on how this can be appropriately costed for and supported by funding bodies and research teams, as well as providing guidance on recruitment and chairing meetings. We hope that this article can provide valuable input into how to involve the community more inclusively as research partners in qualitative analysis related to stigmatised topics. [ABSTRACT FROM AUTHOR]

Climatic factors act on populations at multiple timescales leading to the separation of long-term climate and shorter-term weather effects. We used passerine counts from 1995 to 2019 in subarctic Alaska (Denali National Park, USA) to assess the impacts of the prior breeding season's weather on breeding season abundance and the impacts of climate measured through shifts in elevational distribution. Weather and climate appear to have had opposing effects on the abundance of some shrub-associated species as evidenced by a positive response to nesting phase temperature over a 1-year lag and a negative response to warming-induced shifts in shrub-dominated habitats over the long term. The latter response was indicated by declines in abundance which occurred in some part through portions of these populations shifting upslope of our fixed sampling frame. Overall, the abundance of species was related to one or more of the lagged effects of weather and the effects of weather alone drove nearly twofold variation in annual abundance in most species. The effect of nesting phase temperature was a strong positive predictor at both community and individual species levels, whereas arrival phase temperature had weak support at both levels. The effects of total precipitation during the nesting phase and snowmelt timing shared mixed support at community and species levels, but generally indicated higher abundance following seasons that were drier and had earlier snowmelt. Together, our findings of opposing effects of climatic variables at different timescales have implications for understanding the mechanisms of population and distributional change in passerines in the subarctic. [ABSTRACT FROM AUTHOR]

Inferences about the mechanisms of distributional change are often made from simple assessments of variation in the geographical positions of populations. However, direct assessments of species' responses to local habitat change may be necessary for proper understanding of the drivers of distributional dynamics.Amplified climate warming is inducing cascading impacts in boreal‐tundra regions including the expansion of conifers and deciduous shrubs (shrubs). In Denali National Park (Denali), Alaska, passerine birds are exhibiting rapid upslope shifts in distribution but the relative roles of conifer and shrub (woody vegetation) expansion in driving these shifts are unknown. Without directly assessing passerine‐vegetation dynamics, the assumption has been that the observed upslope shifts are indicative of shrub‐adapted passerines tracking the upslope expansion of shrubs. Here, we jointly investigate the processes of conifer and shrub expansion and their relationship to changes in passerine abundance in Denali.We used a remotely sensed vegetation cover timeseries (1985–2020) to assess the topographic and edaphic correlates of conifer and shrub expansion. We then assessed the impacts of changes in shrub and conifer cover on the relative abundance of 12 passerine species (1995–2020).Shrub and conifer colonization rates were highest at intermediate elevations near treeline. However, forest‐ and shrub‐adapted passerines differed in terms of the location in which their response was concentrated relative to treeline. The population growth rates of forest‐adapted passerines exhibited stronger effects of woody vegetation expansion at sites that were initially above treeline (IAT). In contrast, the population growth rates of shrub‐adapted passerines exhibited the negative effects of conifer expansion together with the positive effects of shrub expansion at initially below treeline sites. However, they showed a weak response to woody vegetation expansion at sites that were IAT.Below treeline conifer infilling appears to be pushing the elevational distributions of shrub‐adapted passerines upslope rather than these species following the pull of modest shrub expansion above treeline, as previously assumed.Overall, our findings illustrate the need for explicitly accommodating heterogeneity in habitat change at small spatial scales to properly view the distributional response, particularly when habitat change is concentrated at ecotones. [ABSTRACT FROM AUTHOR]

Clearly defined terms are essential for reporting and understanding research findings, and inconsistent terminology can complicate efforts to compare findings from different studies. In this article, we reiterate and clarify recommended terms for describing Golden Eagle ( Aquila chrysaetos) territory occupancy and reproduction. Several authors have provided recommendations for reporting data on raptor reproduction, but our literature review showed that authors continue to use different, often ambiguous and undefined, terms. The inconsistent use of terminology by researchers has been continued and expanded by lawmakers, regulators, and managers, perpetuating confusion. We recommend that authors clearly define and reference all terminology that they use, and we caution against use of the term 'active' to describe a nest or nesting territory, because it is tainted with a history of inconsistent use. We provide a glossary of recommended terms for Golden Eagles and other large, long-lived raptors. [ABSTRACT FROM AUTHOR]

The article features Merlins (Falco columbarius) taking dead or injured prey in Denali, Alaska. It notes that Merlins prey mostly on small birds, insects, and small mammals through various hunting techniques. It adds that there are reports of Merlins taking injured prey such as the observed scavenging road-killed snowshoe hare (Lepus americanus) in Denali. It states that snowshoe hare are used as live prey and carrion by several species of avian and terrestrial predators and scavengers.

A letter to the editor is presented discussing an examination of the stomach contents of a northern pike.

The Arctic Warbler (Phylloscopus borealis) is a cryptically plumed songbird with an uncommon Nearctic–Paleotropical migratory strategy. Using light‐level geolocators, we provide the first documentation of the migratory routes and wintering locations of two territorial adult male Arctic Warblers from Denali National Park and Preserve, Alaska. After accounting for position estimation uncertainties and biases, we found that both individuals departed their breeding grounds in early September, stopped over in southeastern Russia and China during autumn migration, then wintered in the Philippines and the island of Palau. Our documentation of Arctic Warbler wintering on Palau suggests that additional study is needed to document their wintering range. Our study provides hitherto unknown information on stopover and wintering locations for Arctic Warblers and indicates that this species may migrate further overwater than previously thought. [ABSTRACT FROM AUTHOR]

Perturbation analysis is a powerful tool to study population and community dynamics. This article describes expressions for sensitivity metrics reflecting changes in equilibrium occupancy resulting from small changes in the vital rates of patch occupancy dynamics (i.e., probabilities of local patch colonization and extinction). We illustrate our approach with a case study of occupancy dynamics of Golden Eagle (Aquila chtysaetos) nesting territories. Examination of the hypothesis of system equilibrium suggests that the system satisfies equilibrium conditions. Estimates of vital rates obtained using patch occupancy models are used to estimate equilibrium patch occupancy of eagles. We then compute estimates of sensitivity metrics and discuss their implications for eagle population ecology and management. Finally, we discuss the intuition underlying our sensitivity metrics and then provide examples of ecological questions that can be addressed using perturbation analyses. For instance, the sensitivity metrics lead to predictions about the relative importance of local colonization and local extinction probabilities in influencing equilibrium occupancy for rare and common species. [ABSTRACT FROM AUTHOR]

The peregrine falcon (Falco peregrinus) and the gyrfalcon (Falco rusticolus) are top avian predators of Arctic ecosystems. Although existing monitoring efforts are well established for both species, collaboration of activities among Arctic scientists actively involved in research of large falcons in the Nearctic and Palearctic has been poorly coordinated. Here we provide the first overview of Arctic falcon monitoring sites, present trends for long-term occupancy and productivity, and summarize information describing abundance, distribution, phenology, and health of the two species. We summarize data for 24 falcon monitoring sites across the Arctic, and identify gaps in coverage for eastern Russia, the Arctic Archipelago of Canada, and East Greenland. Our results indicate that peregrine falcon and gyrfalcon populations are generally stable, and assuming that these patterns hold beyond the temporal and spatial extents of the monitoring sites, it is reasonable to suggest that breeding populations at broader scales are similarly stable. We have highlighted several challenges that preclude direct comparisons of Focal Ecosystem Components (FEC) attributes among monitoring sites, and we acknowledge that methodological problems cannot be corrected retrospectively, but could be accounted for in future monitoring. Despite these drawbacks, ample opportunity exists to establish a coordinated monitoring program for Arctic-nesting raptor species that supports CBMP goals. [ABSTRACT FROM AUTHOR]

Rock ptarmigan (Lagopus muta) and willow ptarmigan (L. lagopus) are Arctic birds with a circumpolar distribution but there is limited knowledge about their status and trends across their circumpolar distribution. Here, we compiled information from 90 ptarmigan study sites from 7 Arctic countries, where almost half of the sites are still monitored. Rock ptarmigan showed an overall negative trend on Iceland and Greenland, while Svalbard and Newfoundland had positive trends, and no significant trends in Alaska. For willow ptarmigan, there was a negative trend in mid-Sweden and eastern Russia, while northern Fennoscandia, North America and Newfoundland had no significant trends. Both species displayed some periods with population cycles (short 3–6 years and long 9–12 years), but cyclicity changed through time for both species. We propose that simple, cost-efficient systematic surveys that capture the main feature of ptarmigan population dynamics can form the basis for citizen science efforts in order to fill knowledge gaps for the many regions that lack systematic ptarmigan monitoring programs. [ABSTRACT FROM AUTHOR]

For migrating animals, realized migration routes and timing emerge from hundreds or thousands of movement decisions made along migration routes. Local weather conditions along migration routes continually influence these decisions, and even relatively small changes in en route weather may cumulatively result in major shifts in migration patterns. Here, we analysed satellite tracking data to score a discrete navigation decision by a large migratory bird as it navigated a high-latitude, 5000m elevation mountain range to understand how those navigational decisions changed under different weather conditions. We showed that wind conditions in particular areas along the migration pathway drove a navigational decision to reroute a migration; conditions encountered predictably resulted in migrants routing either north or south of the mountain range. With abiotic conditions continuing to change globally, simple decisions, such as the one described here, might additively emerge into new, very different migration routes. [ABSTRACT FROM AUTHOR]

Vertebrate populations throughout the circumpolar north often exhibit cyclic dynamics, and predation is generally considered to be a primary driver of these cycles in a variety of herbivore species. However, weather and climate play a role in entraining cycles over broad landscapes and may alter cyclic dynamics, although the mechanism by which these processes operate is uncertain. Experimental and observational work has suggested that weather influences primary productivity over multi-year time periods, suggesting a pathway through which weather and climate may influence cyclic herbivore dynamics. Using long-term monitoring data, we investigated the relationships among multi-year weather conditions, measures of primary productivity, and the abundance of two cyclic herbivore species: snowshoe hare and northern red-backed vole. We found that precipitation (rain and snow) and growing season temperatures were strongly associated with variation in primary productivity over multi-year time horizons. In turn, fourfold variation in the amplitude of both the hare and vole cycles observed in our study area corresponded to long-term changes in primary productivity. The congruence of our results for these two species suggests a general mechanism by which weather and climate might influence cyclic herbivore population dynamics. Our findings also suggested that the association between climate warming and the disappearance of cycles might be initiated by changes in primary productivity. This work provides an explanation for observed influences of weather and climate on primary productivity and population cycles and will help our collective understanding of how future climate warming may influence these ecological phenomena in the future. [ABSTRACT FROM AUTHOR]

Conserving wide-ranging animals requires knowledge about their year-round movements and resource use. Golden Eagles ( Aquila chrysaetos) exhibit a wide range of movement patterns across North America. We combined tracking data from 571 Golden Eagles from multiple independent satellite-telemetry projects from North America to provide a comprehensive look at the magnitude and extent of these movements on a continental scale. We compared patterns of use relative to four alternative administrative and ecological mapping systems, namely Bird Conservation Regions (BCRs), U.S. administrative migratory bird flyways, Migratory Bird Joint Ventures, and Landscape Conservation Cooperatives. Our analyses suggested that eagles initially captured in eastern North America used space differently than those captured in western North America. Other groups of eagles that exhibited distinct patterns in space use included long-distance migrants from northern latitudes, and southwestern and Californian desert residents. There were also several groupings of eagles in the Intermountain West. Using this collaborative approach, we have identified large-scale movement patterns that may not have been possible with individual studies. These results will support landscape-scale conservation measures for Golden Eagles across North America. [ABSTRACT FROM AUTHOR]

It is generally the case that a significant degree of uncertainty exists concerning the behavior of ecological systems. Adaptive management has been developed to address such structural uncertainty, while recognizing that decisions must be made without full knowledge of how a system behaves. This paradigm attempts to use new information that develops during the course of management to learn how the system works. To date, however, adaptive management has used a very limited information set to characterize the learning that is possible. This paper uses an extension of the Partial Observable Markov Decision Process (POMDP) framework to expand the information set used to update belief in competing models. This feature can potentially increase the speed of learning through adaptive management, and lead to better management in the future. We apply this framework to a case study wherein interest lies in managing recreational restrictions around golden eagle (Aquila chrysaetos) nesting sites. The ultimate management objective is to maintain an abundant eagle population in Denali National Park while minimizing the regulatory burden on park visitors. In order to capture this objective, we developed a utility function that trades off expected breeding success with hiker access. Our work is relevant to the management of human activities in protected areas, but more generally demonstrates some of the benefits of POMDP in the context of adaptive management. [ABSTRACT FROM AUTHOR]

Snowshoe hares ( Lepus americanus Erxleben, 1777) fluctuate in 9-10 year cycles throughout much of their North American range. Regional synchrony has been assumed to be the rule for these cycles, so that hare populations in virtually all of northwestern North America have been assumed to be in phase. We gathered qualitative and quantitative data on hare numbers and fur returns of Canada lynx ( Lynx canadensis Kerr, 1792) in the boreal forest regions of Alaska, Yukon, Northwest Territories, and northern British Columbia to describe synchrony in the time window of 1970-2012. Broad-scale synchrony in lynx fur returns was strong from 1970 to about 1995 but then seemed to break down in different parts of this region. Hare populations at 20 sites in Alaska, the Yukon, and Northwest Territories showed peak populations that lagged by 1-4 years during the 1990s and 2000s cycles. The simplest hypothesis to explain these patterns of asynchrony in hare cycles is the movement of predators from British Columbia north into the Yukon and then east into the Northwest Territories and west into Alaska. A traveling wave of these cycles is clearly seen in the lynx fur returns from western Canada and Alaska from 1970 to 2009. One consequence of a failure of synchrony is that hare predators like Canada lynx and Great-horned Owls ( Bubo virginianus (Gmelin, 1788)) can move from one adjacent area to the next within this region and survive long enough to prolong low densities in hare populations that have declined earlier. [ABSTRACT FROM AUTHOR]

Unintended effects of recreational activities in protected areas are of growing concern. We used an adaptive-management framework to develop guidelines for optimally managing hiking activities to maintain desired levels of territory occupancy and reproductive success of Golden Eagles (Aquila chrysaetos) in Denali National Park (Alaska, U.S.A.). The management decision was to restrict human access (hikers) to particular nesting territories to reduce disturbance. The management objective was to minimize restrictions on hikers while maintaining reproductive performance of eagles above some specified level. We based our decision analysis on predictive models of site occupancy of eagles developed using a combination of expert opinion and data collected from 93 eagle territories over 20 years. The best predictive model showed that restricting human access to eagle territories had little effect on occupancy dynamics. However, when considering important sources of uncertainty in the models, including environmental stochasticity, imperfect detection of hares on which eagles prey, and model uncertainty, restricting access of territories to hikers improved eagle reproduction substantially. An adaptive management framework such as ours may help reduce uncertainty of the effects of hiking activities on Golden Eagles. [ABSTRACT FROM AUTHOR]

The article offers information on the understanding of these seasonal movements continues to rapidly increase with the advancement of tracking technology across North America and the Atlantic Ocean. Topics discussed include information on the migration of Blackpolls from central and western breeding populations; discussions on the longitude estimates due to extensive overlap with the autumnal equinox; and the the extent to which migratory songbirds adapt their cross-continent.