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Copyright of Eurasian Journal of Veterinary Sciences is the property of Eurasian Journal of Veterinary Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The arctic tern Sterna paradisaea completes the longest known annual return migration on Earth, traveling between breeding sites in the northern arctic and temperate regions and survival/molt areas in the Antarctic pack‐ice zone. Salomonsen (1967, Biologiske Meddelelser, Copenhagen Danske Videnskabernes Selskab, 24, 1) put forward a hypothetical comprehensive interpretation of this global migration pattern, suggesting food distribution, wind patterns, sea ice distribution, and molt habits as key ecological and evolutionary determinants. We used light‐level geolocators to record 12 annual journeys by eight individuals of arctic terns breeding in the Baltic Sea. Migration cycles were evaluated in light of Salomonsen's hypotheses and compared with results from geolocator studies of arctic tern populations from Greenland, Netherlands, and Alaska. The Baltic terns completed a 50,000 km annual migration circuit, exploiting ocean regions of high productivity in the North Atlantic, Benguela Current, and the Indian Ocean between southern Africa and Australia (sometimes including the Tasman Sea). They arrived about 1 November in the Antarctic zone at far easterly longitudes (in one case even at the Ross Sea) subsequently moving westward across 120–220 degrees of longitude toward the Weddell Sea region. They departed from here in mid‐March on a fast spring migration up the Atlantic Ocean. The geolocator data revealed unexpected segregation in time and space between tern populations in the same flyway. Terns from the Baltic and Netherlands traveled earlier and to significantly more easterly longitudes in the Indian Ocean and Antarctic zone than terns from Greenland. We suggest an adaptive explanation for this pattern. The global migration system of the arctic tern offers an extraordinary possibility to understand adaptive values and constraints in complex pelagic life cycles, as determined by environmental conditions (marine productivity, wind patterns, low‐pressure trajectories, pack‐ice distribution), inherent factors (flight performance, molt, flocking), and effects of predation/piracy and competition. [ABSTRACT FROM AUTHOR]

Korea is located within the East Asian-Australian flyway of wild migratory birds during the fall and winter seasons. Consequently, the likelihood of introduction of numerous subtypes and pathotypes of the Avian influenza (AI) virus to Korea has been thought to be very high. In the current study, we surveyed wild bird feces for the presence of AI virus that had been introduced to Korea between September 2017 and February 2018. To identify and characterize the AI virus, we employed commonly used methods, namely, virus isolation (VI) via egg inoculation, real-time reverse transcription-polymerase chain reaction (rRT-PCR), conventional RT-PCR (cRT-PCR) and a newly developed next generation sequencing (NGS) approach. In this study, 124 out of 11,145 fresh samples of wild migratory birds tested were rRT-PCR positive; only 52.0% of VI positive samples were determined as positive by rRT-PCR from fecal supernatant. Fifty AI virus specimens were isolated from fresh fecal samples and typed. The cRT-PCR subtyping results mostly coincided with the NGS results, although NGS detected the presence of 11 HA genes and four NA genes that were not detected by cRTPCR. NGS analysis confirmed that 12% of the identified viruses were mixed-subtypes which were not detected by cRT-PCR. Prevention of the occurrence of AI virus requires a workflow for rapid and accurate virus detection and verification. However, conventional methods of detection have some limitations. Therefore, different methods should be combined for optimal surveillance, and further studies are needed in aspect of the introduction and application of new methods such as NGS. [ABSTRACT FROM AUTHOR]

Window collisions pose a serious risk to birds, second only to domestic/feral cats. We sought to quantify the impacts of this threat at Radford University, a campus situated within a rural landscape and along a major migratory route (New River). We searched for evidence of bird-window collisions (BWCs) at 15 buildings in 2018 and 2019. In nearly 1,000 hours of surveys we discovered 51 birds (23 species) thought to result from BWCs. Increased window area tracked with a greater number of mortalities/building. Building height and surrounding vegetation metrics were not significantly related to BWCs. Species' residency status did not significantly influence mortality events. Compared to BWC surveys nationwide, our number of mortalities was low, especially relative to our substantial surveying effort. Although this finding might suggest that Radford University buildings are not a significant source of mortality for birds, we recognize that (1) a priori surveying biases likely underestimated actual mortalities, and that (2) Radford University's architectural changes in the last several years are increasing the likelihood of BWCs in the future. We suggest that Radford University explore window decals on current windows and incorporate "bird-friendly" glass on aspects that comprise large proportions of glass. Both of these steps contribute to Radford University's goal of increasing the number of LEED-certified buildings on campus. [ABSTRACT FROM AUTHOR]

Stopover periods in between migratory flights determine the speed of migration and as such may affect birds' fitness. The decision to leave a stopover site is affected by, for example, energy stores and weather conditions. We investigated whether immunological state influences autumn stopover departure decisions in Northern Wheatear (Oenanthe oenanthe), a nocturnal long-distance migrant. We measured three parameters of constitutive immune function: microbial killing capacity, haptoglobin, and total immunoglobulins. None of them explained variation in departure probability, minimum stopover duration, or departure time within the night. Thus, we did not find an effect of the birds' immunological state on stopover departure decisions. [ABSTRACT FROM AUTHOR]

Genetically related highly pathogenic avian influenza viruses (HPAIVs) of H5N6 subtype caused outbreaks simultaneously in East Asia and Europe—geographically distinct regions—during winter 2017–2018. This situation prompted us to consider whether the application of phylogeographic analysis to a particular gene segment of AIVs could provide clues for understanding how AIV had been disseminated across the continent. Here, the N6 NA genes of influenza viruses isolated across the world were subjected to phylogeographic analysis to illustrate the inter- and intracontinental dissemination of AIVs. Those isolated in East Asia during winter and in Mongolia/Siberia during summer were comingled within particular clades of the phylogeographic tree. For AIVs in one clade, their dissemination in eastern Eurasia extended from Yakutia, Russia, in the north to East Asia in the south. AIVs in western Asia, Europe, and Mongolia were also comingled within other clades, indicating that Mongolia/Siberia plays an important role in the dissemination of AIVs across the Eurasian continent. Mongolia/Siberia may therefore have played a role in the simultaneous outbreaks of H5N6 HPAIVs in Europe and East Asia during the winter of 2017–2018. In addition to the long-distance intracontinental disseminations described above, intercontinental disseminations of AIVs between Eurasia and Africa and between Eurasia and North America were also observed. Integrating these results and known migration flyways suggested that the migration of wild birds and the overlap of flyways, such as that observed in Mongolia/Siberia and along the Alaskan Peninsula, contributed to the long-distance intra- and intercontinental dissemination of AIVs. These findings highlight the importance of understanding the movement of migratory birds and the dynamics of AIVs in breeding areas—especially where several migration flyways overlap—in forecasting outbreaks caused by HPAIVs. [ABSTRACT FROM AUTHOR]

Previous research on transnational migration and information and communication technologies (ICTs) demonstrated how ICTs shape transnational social relationships. What remains less explored is how ICTs shape spatial dimensions of such relationships. Also, international educational migrants constitute a substantial part of transnational migration flow, yet their everyday lives are not well studied. Building upon material semiotic scholarship, we examine how ICTs shape socio-spatial dimensions of transnational relationships in the lives of educational migrants, and the impacts that such relationships have on their everyday lives. This research is based on the empirical exploration of 21 in-depth interviews with educational migrants who came from Central Asian and African countries to the Netherlands. We show that spatial relationships, such as co-presence and distance, are not naturally 'given' but are instead enacted in heterogeneous communication practices of educational migrants, and these relationships produce both enabling and constraining effects on their everyday lives. [ABSTRACT FROM AUTHOR]

• We performed a Before-After Control-Impact analysis (BACI) to assess the efficiency of a bat overpass. • An acoustic flight path reconstruction approach was used to quantify bat crossings. • We detected a significant increase of bat crossings between the two periods at the treatment site. • An overpass correctly placed could efficiently restore bat habitat connectivity. Roads have a multitude of negative effects on wildlife, including their prominent role in habitat fragmentation. Habitat fragmentation particularly affects bats during their nightly movements between roosts and foraging areas. Bat overpasses are among the proposed improvements intended to reduce the fragmentation impact of roads, but they have rarely been tested. In this study, we performed a Before-After Control-Impact analysis (BACI) to assess the efficiency of one bat overpass on the number of bat crossings, by using an acoustic flight path reconstruction (AFPR) approach. We obtained 888 bat crossings of five taxa. Our results showed that the number of bat crossings increased significantly after the installation of the bat overpass. Finally, we demonstrated that an overpass correctly placed with respect to a narrow commuting route (a twenty-meter-wide hedgerow) could efficiently restore bat habitat connectivity. [ABSTRACT FROM AUTHOR]

To better understand the ecological implications of global climate change for species that display geographically and seasonally dynamic life‐history strategies, we need to determine where and when novel climates are projected to first emerge. Here, we use a multivariate approach to estimate time of emergence (ToE) of novel climates based on three climate variables (precipitation, minimum and maximum temperature) at a weekly temporal resolution within the Western Hemisphere over a 280‐yr period (2021–2300) under a high emissions scenario (RCP8.5). We intersect ToE estimates with weekly estimates of relative abundance for 77 passerine bird species that migrate between temperate breeding grounds in North America and southern tropical and subtropical wintering grounds using observations from the eBird citizen‐science database. During the non‐breeding season, migrants that winter within the tropics are projected to encounter novel climates during the second half of this century. Migrants that winter in the subtropics are projected to encounter novel climates during the first half of the next century. During the beginning of the breeding season, migrants on their temperate breeding grounds are projected to encounter novel climates during the first half of the next century. During the end of the breeding season, migrants are projected to encounter novel climates during the second half of this century. Thus, novel climates will first emerge ca 40–50 yr earlier during the second half of the breeding season. These results emphasize the large seasonal and spatial variation in the formation of novel climates, and the pronounced challenges migratory birds are likely to encounter during this century, especially on their tropical wintering grounds and during the transition from breeding to migration. When assessing the ecological implications of climate change, our findings emphasize the value of applying a full annual cycle perspective using standardized metrics that promote comparisons across space and time. [ABSTRACT FROM AUTHOR]

King Rails (Rallus elegans) are a secretive marshbird often separated for management purposes into resident and migratory populations. The objective of this research was to gain a better understanding of where Midwest King Rails migrate and winter. Satellite transmitters were placed on nine King Rails captured in Ohio (USA). Autumn migration data was available for four individuals and spring migration data for two individuals. Autumn migration was completed in ≤ 5 days. During autumn migration, three individuals migrated from Ohio to the Gulf Coast, and one individual migrated from Pennsylvania to the southern Atlantic coast. Spring migration lasted longer and had more stopovers than autumn migration. During spring, one individual migrated from Louisiana to Indiana, and one individual migrated from Georgia to Louisiana, indicating likely immigration and emigration between coastal resident and Midwest King Rail populations. Departure dates from the breeding range varied from 30 August to 20 October and spring arrival date to the Upper Midwest was 20 April. All four of the individuals monitored were exposed to potential harvest while on the wintering range. We recommend continued satellite marking of the migratory population across their breeding range to improve understanding of the annual lifecycle of King Rail. [ABSTRACT FROM AUTHOR]

Conventional monitoring tools are seldom effective for studying the ecology of rare and elusive mammals. In the present study, we use automated ultrasound detectors to provide information about seasonal activity of the greater noctule bat (Nyctalus lasiopterus), the largest and one of least known European bats. We selected localities within Central Europe with diverse geomorphological contexts, including rivers of different sizes and mountain passes. The study demonstrates the capability of the automatic recording approach to achieve bioacoustic discrimination of this species, but also pointed to the persistent need of integrating results from automatic classification software applications with the feedback from manual approaches. The high throughput capacity of the assay proved to be efficient, and the regular occurrence of the species was identified at two localities. These locations are associated with two known and intensely used migratory corridors of winged animals going through Vltava River valley and Červenohorské Saddle in Jeseníky mountains, as illustrated also by the activity patterns of other migratory species. Together with the occurrence of spring and autumn peaks in activity, these findings are in concordance with the plesiomorphic condition in pipistrelloid bats, showing also migratory behavior, and represent further indirect evidence of migration of the greater noctule. This pattern could be facilitated by the trophic niche of the species, involving predation of migrating songbirds. Differences in phenology of migratory species observed at particular sites likely mirror position of the locality in relation to migration flyways, seasonal and geographic variation in prey availability and energy demands etc. Further application of bioacoustic monitoring and other tools is necessary to obtain detailed information about the range and movement ecology of the species in higher latitudes. [ABSTRACT FROM AUTHOR]

Identifying the processes that determine avian migratory strategies in different environmental contexts is imperative to understanding the constraints to survival and reproduction faced by migratory birds across the planet.We compared the spring migration strategies of Fork‐tailed Flycatchers (Tyrannus s. savana) that breed at south‐temperate latitudes (i.e., austral migrants) vs. tropical latitudes (i.e., intratropical migrants) in South America. We hypothesized that austral migrant flycatchers are more time‐selected than intratropical migrants during spring migration. As such, we predicted that austral migrants, which migrate further than intratropical migrants, will migrate at a faster rate and that the rate of migration for austral migrants will be positively correlated with the onset of spring migration.We attached light‐level geolocators to Fork‐tailed Flycatchers at two tropical breeding sites in Brazil and at two south‐temperate breeding sites in Argentina and tracked their movements until the following breeding season.Of 286 geolocators that were deployed, 37 were recovered ~1 year later, of which 28 provided useable data. Rate of spring migration did not differ significantly between the two groups, and only at one site was there a significantly positive relationship between date of initiation of spring migration and arrival date.This represents the first comparison of individual migratory strategies among conspecific passerines breeding at tropical vs. temperate latitudes and suggests that austral migrant Fork‐tailed Flycatchers in South America are not more time‐selected on spring migration than intratropical migrant conspecifics. Low sample sizes could have diminished our power to detect differences (e.g., between sexes), such that further research into the mechanisms underpinning migratory strategies in this poorly understood system is necessary. [ABSTRACT FROM AUTHOR]

Highlights • An archipelagic landscape ecological network (ALEN) was established at dual spatial scales. • The ALEN consisted of four types of elements: nodes, routes, sources, and corridors. • Methods of Euclidean distance and Least cost distance were integrated to establish the ALEN. • ALEN in Miaodao Archipelago realized full connectivity across archipelago and island scales. • Optimization measures based on the landscape structure of the ALEN were proposed. Abstract An archipelagic landscape ecological network (ALEN) is important for optimizing the bird migration route and providing reference for island biodiversity maintenance. The ALEN with full connectivity at dual spatial scales was established in this study. Ecological nodes and routes at archipelago scale, as well as ecological sources and corridors at island scale, were identified to constitute the ALEN based on the habitat suitability and integrating the approaches of Euclidean distance and Least cost distance. Then, the landscape structures of the ALEN were analyzed and the optimization measures were proposed to improve the habitat quality and network connectivity. Miaodao Archipelago, an important and typical archipelago in North China, was selected as the study area. Results indicated that the ALEN was composed of 32 nodes and 81 routes at archipelago scale, and 42 sources and 76 corridors at island scale. At archipelago scale, the ecological efficiency of the ALEN was determined by the landscape resistance and position of different islands, and the landscape structure optimization should focus on the islands that involved the indispensable routes. At island scale, the number and spatial distribution of the sources, as well as the landscape structure of the corridors, contributed the most to the ecological efficiency. More ecological sources with uniform distribution should be added, and the corridor width of 50 m was practical to implement the ALEN. The ALEN realized the full connectivity, that is, the bird species could flow (flight or walk) all over the nodes and sources along the routes and corridors across the dual spatial scales, and the balance of efficiency and cost was achieved. The ALEN could be widely applied in different archipelagos with distinct ecological functions and external disturbances. [ABSTRACT FROM AUTHOR]

Nocturnal avian migration flyways remain an elusive concept, as we have largely lacked methods to map their full extent. We used the network of European weather radars to investigate nocturnal bird movements at the scale of the European flyway. We mapped the main migration directions and showed the intensity of movement across part of Europe by extracting biological information from 70 weather radar stations from northern Scandinavia to Portugal, during the autumn migration season of 2016. On average, over the 20 nights and all sites, 389 birds passed per 1 km transect per hour. The night with highest migration intensity showed an average of 1621 birds km–1 h–1 passing the radar stations, but there was considerable geographical and temporal variation in migration intensity. The highest intensity of migration was seen in central France. The overall migration directions showed strong southwest components. Migration dynamics were strongly related to synoptic wind conditions. A wind‐related mass migration event occurred immediately after a change in wind conditions, but quickly diminished even when supporting winds continued to prevail. This first continental‐scale study using the European network of weather radars demonstrates the wealth of information available and its potential for investigating large‐scale bird movements, with consequences for ecosystem function, nutrient transfer, human and livestock health, and civil and military aviation. [ABSTRACT FROM AUTHOR]

Copyright of Avian Diseases is the property of American Association of Avian Pathologists, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Biogeography, systematics and taxonomy are complementary scientific disciplines. To understand a species’ origin, migration routes, distribution and evolutionary history, it is first necessary to establish its taxonomic boundaries. Here, we use an integrative approach that takes advantage of complementary disciplines to resolve an intriguing scientific question. Populations of an unknown moss found in the Canary Islands (Tenerife Island) resembled two different Californian endemic species: Orthotrichum shevockii and O. kellmanii. To determine whether this moss belongs to either of these species and, if so, to explain its presence on this distant oceanic island, we combined the evaluation of morphological qualitative characters, statistical morphometric analyses of quantitative traits, and molecular phylogenetic inferences. Our results suggest that the two Californian mosses are conspecific, and that the Canarian populations belong to this putative species, with only one taxon thus involved. Orthotrichum shevockii (the priority name) is therefore recognized as a morphologically variable species that exhibits a transcontinental disjunction between western North America and the Canary Islands. Within its distribution range, the area of occupancy is limited, a notable feature among bryophytes at the intraspecific level. To explain this disjunction, divergence time and ancestral area estimation analyses are carried out and further support the hypothesis of a long-distance dispersal event from California to Tenerife Island. [ABSTRACT FROM AUTHOR]

Black vultures (Coragyps atratus) have been increasing in density and expanding their range in the eastern United States since at least the 1960s. In many areas, their densities have increased to the level where they are causing damage to property and livestock and the number of requests for allowable take permits has increased throughout these areas. The United States Fish and Wildlife Service (USFWS) requires updated information to help inform the number of take permits that could reduce conflicts while meeting obligations under the Migratory Bird Treaty Act. We expanded analyses used to estimate allowable take in Virginia to cover the range of black vultures in the eastern United States. We used the prescribed take level approach, which integrates demographic rates, population size estimates, and management objectives into an estimate of allowable take. We provide estimates of allowable take at 4 different scales: individual states, Bird Conservation Regions, USFWS administrative regions, and flyways. Our updated population time series provides evidence of rapidly increasing black vulture populations in many regions of the eastern United States, with an overall population estimate of approximately 4.26 million in 2015 in the Atlantic and Mississippi Flyways. Estimated allowable take ranged from a few hundred individuals per year in states at the northern end of the species range to approximately 287,000/year over the entire eastern United States. The USFWS has no legal mandate regarding the spatial scale at which take should be managed and we found little biological evidence of subpopulation structure for black vultures in the eastern United States. We suggest that allowable take for the species be implemented at a scale that meets stakeholder objectives (e.g., reducing conflict, and ensuring that black vultures are not extirpated from local areas) and is efficient for administrative and monitoring purposes. Published 2018. This article is a U.S. Government work and is in the public domain in the USA. We estimated allowable lethal take of black vultures at different spatial scales throughout the eastern portion of the United States. Population size of this species has been increasing rapidly and sustainable allowable take ranged from a few hundred individuals in states along the northern portion of their range to approximately 287,000 individuals range‐wide in the eastern United States. [ABSTRACT FROM AUTHOR]

This article, or artist's inquiry, was written in concert with the exhibition Instinct Extinct: The Great Pacific Flyway. Beginning with introductions to bird migration, the concept of global flyways and the history of conservation, the text considers the poetics of art-making relative to academic research. Areas of artistic exploration include a map depicting California's changing waterscape, video portraits of people of the flyway and assemblages of invented and found avian artifacts. The article concludes with a review of current environmental conditions affecting migratory birds and some reflective passages. [ABSTRACT FROM AUTHOR]

Seasonal bird (Aves) migration between breeding and wintering areas, often located on different continents, can facilitate the spreading of tick species (Acari: Ixodida) and of tick-borne pathogens. The aim of the study was to analyse the occurrence of ticks dispersed by birds migrating along the Polish Baltic coast during spring and autumn migration. Field research was conducted at the bird ringing station in Wicie, located on the middle of the Polish Baltic coast, in 2011 and 2012 during spring and autumn migration. A total of 2657 birds from 45 species was examined. The most common species inspected were European robin (Erithacus rubecula) (63.3%), song thrush (Turdus philomelos) (5.13%), and goldcrest (Regulus regulus) (4.5%). Overall, 3129 ticks belonging to six species were collected: Ixodes ricinus (1650 larvae, 1390 nymphs and 1 male), Ixodes frontalis (20 larvae, 20 nymphs), Ixodes arboricola (35 larvae), Dermacentor reticulatus (1 larva), and Haemaphysalis punctata (1 nymph). Ten larvae and one nymph could only be identified to the genus level Ixodes. Ticks were located on various parts of the head: on the corner of the beak (75.0%), near the eyes (14.6%), on the chin (4.4%), near the ears (4.4%), on the neck (1.1%), and in the beak (0.5%). The overall tick prevalence was 40.5%. The highest prevalence was for bird species feeding on the ground, covering a medium distance to wintering grounds and migrating at night. Statistically significant differences between the number of ticks and the sex of the host species were detected in blackbirds: males carried more parasites than females, both, during spring and autumn migration. The fact that I. ricinus and other ticks parasitize birds migrating through Poland extends the possibility of the spread of tick-borne diseases. [ABSTRACT FROM AUTHOR]

Bird ringing was established more than a century ago to gather information on bird movements. Since then, ornithologists have systematically collected huge databases of records of birds ringed and subsequently re-encountered, but, to date, there have been few quantitative attempts to identify migratory routes from ringing data. Here, we develop a novel, quantitative method for describing migration routes using ringing data and we applied it to a dataset of 72,827 ring recoveries of the Barn Swallow (Hirundo rustica) through western and central Europe from the EURING and SAFRING databanks spanning 1908-2011. We considered movements of 332 individuals during spring migration and 1509 during autumn migration. The results indicate that, in spring, Barn Swallows enter western Europe through Gibraltar or by crossing the Mediterranean Sea through the Balearic Islands, Sardinia, and the Italian peninsula. They then spread over a wide front. In northern France, Belgium and the Netherlands routes diverge, pointing toward either the British Isles or Denmark and Scandinavia. Autumn migration routes are similar to those in spring. The general migration pattern that emerged from the analyses was consistent with previous descriptions of migratory movements of this well-known species. However, this analysis also revealed some previously undocumented migration patterns. For instance, in spring, some migrants moved from the Balearic Islands to Corsica and Italy, thus making a rather long eastward crossing of the Mediterranean Sea. In autumn, some migrants moved from the Balkan Peninsula westwards toward Italy. Analyses restricted to recoveries within the same spring or the same autumn and to birds found dead showed similar patterns. Our procedure was, therefore, able to identify migration patterns over a large geographical area, and may be extended to those species for which large datasets of ring recoveries or sight-resight data are available. [ABSTRACT FROM AUTHOR]

The flexibility for migrant land birds to be able to travel long distances rapidly without stopovers, and thus to cross wide inhospitable areas such as deserts and oceans, is likely to be a major determinant of their survival during migration. We measured variation in flight distance, speed and duration of major stopovers (more than 2 days), using geolocator tracks of 35 Whinchats Saxicola rubetra that migrated successfully from central Nigeria to Eastern Europe in spring, and examined how these measures changed, or depended on age, when crossing the barriers of the Sahara or the Mediterranean Sea. In all, 31% of Whinchats crossed at least the Sahara and the Mediterranean before a major stopover and 17% travelled over 4751 km on average without any major stopovers. Flight distance and speed during, and duration of major stopovers after, crossing the Mediterranean Sea were indistinguishable from migration over Continental Europe. Speed during a migration leg was lowest crossing Continental Europe and fastest, with longer duration major stopovers afterwards, when crossing the Sahara, but there was much individual variation, and start date of migration was also a good predictor of stopover duration. As the distance travelled during a leg increased, so major stopover duration afterwards increased (1 day for every 1000 km), but the speed of travel during the leg had no effect. There were no differences in any migration characteristics with age, other than an earlier start date for adult birds. The results suggest that adaptive shortening or even dropping of daily stopovers may occur often, allowing rapid, long‐distance migration at the cost of major stopovers afterwards, but such behaviour is not restricted to or always found when crossing barriers, even for birds on their first spring migration. The results may highlight the importance of stopover sites rather than barrier width as the likely key component to successful migration. Individual variation in spring migration may indicate that small passerine migrants like Whinchats may be resilient to future changes in the extent of barriers they encounter, although this may not be true of first autumn migrations or if stopover sites are lost. [ABSTRACT FROM AUTHOR]

The article reviews the exhibitions "Parrot Architecture" at the Dallas Contemporary, fromApril 16 to August 21, 2022 and "Flight Paths and Floor Plans" at Talley Dunn Gallery, from May 14 to June 25, 2022, in Dallas, Texas, exploring the concept of inter-species communication within art.

Many migratory goose populations have thrived over the past decades and their reliance on agricultural resources has often led to conflicts. Control and management measures are sought after but since migratory geese use several sites in their annual cycle, local management actions should consider their potential effects further down the flyway.We used a behaviour‐based migration model to illustrate the consequences of management actions involving hunting, derogation shooting and scaring at single or multiple locations along the flyway, considering various mechanisms of how geese might perceive shooting/hunting. Furthermore, as a proxy for the agricultural damage caused, we calculated the per capita biomass consumption between scenarios—both over time and cumulatively.We found that hunting, shooting and scaring can result in a suite of direct and indirect consequences on migration and foraging behaviour. Most importantly, hunting/shooting on a particular site had implications not only for the behaviour at the actual site but also for behaviour at, and use of, other sites. Furthermore, the specific consequences of shooting/hunting could be counter‐intuitive, that is, aggravate rather than alleviate agricultural damage, depending on where along the migration route changes had taken place and the mechanisms through which hunting/shooting was assumed to affect geese.Synthesis and applications. Management plans are being discussed or implemented for several migratory goose populations and often include shooting, hunting or scaring at one or multiple locations. Using a behaviour‐based model, we assessed the consequences of such local management measures and found that they can indeed lead to a reduction of agricultural conflicts locally but may also aggravate the conflict or shift it to other sites along the flyway. Thus, we recommend the use of these models to scrutinize the efficiency of specific management measures and to assist in identifying an international management regime that minimizes conflicts on a flyway level while still maintaining migratory populations. Management plans are being discussed or implemented for several migratory goose populations and often include shooting, hunting or scaring at one or multiple locations. Using a behaviour‐based model, we assessed the consequences of such local management measures and found that they can indeed lead to a reduction of agricultural conflicts locally but may also aggravate the conflict or shift it to other sites along the flyway. Thus, we recommend the use of these models to scrutinize the efficiency of specific management measures and to assist in identifying an international management regime that minimizes conflicts on a flyway level while still maintaining migratory populations. [ABSTRACT FROM AUTHOR]

We used light-level-based geolocation to study the spatio-temporal behaviour of Siberian Rubythroats Calliope calliope breeding in the Amur region of the Russian Far East. Three retrieved devices revealed long-distance migrations, with southwestward movement from Amur through Northeast China in autumn, with the tracked individuals reaching their wintering grounds in southern China and Indochina without major detours and apparently on a route slightly further west than that of the return migration in spring. A single stopover occurred in two of the three birds in both spring and autumn in China. Migration was faster in spring compared to autumn. The birds spent most of their time in seasonal habitats on their temperate breeding sites, and in less seasonal habitats on their tropical wintering grounds. Departure from and arrival at their breeding site coincided with decreasing and increasing vegetation greenness, respectively. This is the first study presenting year-round tracking data for a songbird migrating from mainland Eurasia to Southeast Asia along the East Asian flyway. [ABSTRACT FROM AUTHOR]

Seasonal variation in migratory routes seems to be a common trait among many Afro-Palearctic migrants, but there are only few examples of species or populations which shift between entirely different flyways in autumn and spring. To identify non-breeding regions and seasonal differences in migration strategies we tracked Barn Swallows (Hirundo rustica) from a Baltic breeding population by light-level geolocators. Using novel analytical tools, we provide the first full annual tracks for European swallows. The main non-breeding residency sites of the tracked individuals were located in Southern Africa and all birds followed a distinct counterclockwise loop migration pattern shifting from the central Afro-Palearctic flyway in autumn to the eastern Afro-Palearctic flyway in spring. Despite the elongated detour through the Arabian Peninsula and the Caucasus Mountains, spring migration was faster than autumn migration in all of the tracked males and one out of two females, implying favorable conditions en route that allow for more efficient and faster traveling. [ABSTRACT FROM AUTHOR]

Changes in demographic rates underpin changes in population size, and understanding demographic rates can greatly aid the design and development of strategies to maintain populations in the face of environmental changes. However, acquiring estimates of demographic parameters at relevant spatial scales is difficult. Measures of annual survival rates can be particularly challenging to obtain because large‐scale, long‐term tracking of individuals is difficult and the resulting data contain many inherent biases. In recent years, advances in both tracking and analytical techniques have meant that, for some taxonomic groups, sufficient numbers of survival estimates are available to allow variation within and among species to be explored. Here we review published estimates of annual adult survival rates in shorebird species across the globe, and construct models to explore the phylogenetic, geographical, seasonal and sex‐based variation in survival rates. Models of 295 survival estimates from 56 species show that survival rates calculated from recoveries of dead individuals or from return rates of marked individuals are significantly lower than estimates from mark–recapture models. Survival rates also vary across flyways, largely as a consequence of differences in the genera that have been studied and the analytical methods used, with published estimates from the Americas and from smaller shorebirds (Actitis, Calidris and Charadrius spp.) tending to be underestimated. By incorporating the analytical method used to generate each estimate within a mixed model framework, we provide method‐corrected species‐specific and genus‐specific adult annual survival estimates for 52 species of 15 genera. [ABSTRACT FROM AUTHOR]

We used ringed-recoveries to assess: 1) the connectivity (movements of individuals) between the three putative flyways (north-west Europe, central Europe, south-west Asia) of common pochards in the Western Palearctic, 2) possible spatio-temporal variations in the distribution of the species, and, 3) temporal evolution in spring and autumn migration dates. Based on winter counts of common pochards in the north-west European flyway, we distinguished three periods in the analyses (1960-1990, 1991-2000 and 2001-2016), which correspond to successive periods of population increase, peak and decline, respectively. Whatever the season (wintering or breeding) and period of ringing, large probabilities of ring-recoveries outside the flyway of origin (ringing) were recorded, suggesting a high connectivity between the three putative flyways. There was a significant trend towards an earlier departure from the wintering area, and an eastward shift of spring recoveries over periods. In contrast, neither autumn/winter recovery locations, nor departure dates from the breeding area in Latvia and Russia changed over periods. The latter results do not support the hypothesis that shortstopping (i.e. a reduction of fall migration distances/delaying of departure dates from the breeding area) could explain the observed decline of wintering common pochards in the north-west European flyway. Indirect recoveries support that large proportions of individuals wintering in western Europe may originate from the south-west Asia flyway and more particularly from a region in Siberia located in the Ob river catchment area. Considering trends in numbers for the three flyways together confirmed the "vulnerable" IUCN status of common pochard in the Western Palearctic as a whole, with a 35% decline over the last decade. The important connectivity between the northwest, central European and southwest Asian flyways call for considering such conservation problems at a much broader scale than the regional flyway. [ABSTRACT FROM AUTHOR]

Until recently, the migration route and wintering areas of Red-necked Phalaropes Phalaropus lobatus breeding in Scotland was a matter of speculation, since no foreign ringing recoveries existed for this population. In 2013, a male fitted with a geolocator the previous year was retrapped on its breeding grounds in Shetland. Data from the tag revealed that the bird had followed a westerly migration route, crossing the Atlantic to North America and travelling south to winter in the Pacific Ocean off the coast of South America - the first recorded instance of a European breeding bird wintering in the Pacific. From just one individual it could not be established whether this migration route was exceptional or representative of the wider Scottish population. Here we report the tracking of two further males that followed a closely similar route. We infer that the transatlantic migration and Pacific wintering grounds of Red-necked Phalaropes breeding in Shetland is more likely to be the rule than the exception, although tracking of females is required to clarify whether they follow a similar route. [ABSTRACT FROM AUTHOR]

Abstract: When and where to move is a fundamental decision to migratory birds, and the fitness‐related costs and benefits of migratory choices make them subject to strong selective forces. Site use and migration routes are outcomes of opportunities in the surrounding landscape, and the optimal migration strategy may be conservative or explorative depending on the variability in the environment occupied by the species. This study applies 25 years of resighting data to examine development in winter migration strategy of pink‐footed geese divided among Denmark, the Netherlands and Belgium, and analyse potential drivers of strategy change as well as individuals’ likelihood to break with migratory tradition. Contrary with the general notion that geese are highly traditional in their winter site use, our results reveal that winter migration strategy is highly dynamic in this species, with an average annual probability of changing strategy of 54%. Strategy was not related to hunting pressure or winter temperature, but could be partly explained by a tracking of food resources in a landscape of rapid land use changes. The probability of individuals changing strategy from year to year varied considerably between birds, and was partly related to sex and age, with young males being the most likely to change. The annual probability of changing wintering strategy increased substantially from ≈40% to ≈60% during the study period, indicating an increasingly explorative behaviour. Our findings demonstrate that individual winter strategies are very flexible and able to change over time, suggesting that phenotypic plasticity and cultural transmission are important drivers of strategy choice in this species. Growing benefits from exploratory behaviours, including the ability to track rapid land use changes, may ultimately result in increased resilience to global change. [ABSTRACT FROM AUTHOR]

Open landfills seem to be playing an increasing role as target feeding areas for several species, not only in their breeding areas or during the winter, but also during the migration period. Evaluating the extent to which landfill sites are used by migrants is crucial to understanding their role in driving stopover decisions during migration, and in the potential health risks linked to feeding on refuse. The aim of this study was to evaluate the role of two open landfills located just before (France) and after (Spain) the East‐Atlantic flyway enters Iberia through the western Pyrenees as potentially important stopover sites for the White Stork populations moving along this route. Overall, we detected that these sites were used by storks that had been ringed from many western European breeding populations, mainly during the migration period, but also in winter. The mean distance between the stork breeding/ringing origin and the landfill sites increased from summer to winter, suggesting that storks breeding further away pass through Iberia later in the season, reflecting population‐specific timing of migration. During the autumn migration period (August–September), the first encountered landfill in France was estimated to be used by c. 1200 storks, and the other in Spain by 4000 storks. Our study hence contributes to a better understanding of the current and potentially hazardous role played by landfill sites in White Stork ecology, which is essential in order to provide management recommendations, and to evaluate the consequences of proposed open landfill closures in Europe. [ABSTRACT FROM AUTHOR]

The article discusses the challenges and opportunities of conserving migratory birds in the East Asian-Australian Flyway (EAAF) which stretches from Russian tundra to New Zealand coasts. Topics include some of the threats facing migratory birds in EAAF such as hunting, the strategic directions in which EAAF research should focus and the importance of increased participation and commitment of EAAF countries to intergovernmental treaties or bilateral agreements in migratory bird conservation.

The Upland Goose (Chloephaga picta picta) is a migratory species of South America, which breeds from September to April in Patagonia (Argentina and Chile) and winters from May to September in the southern Pampas (Argentina). Despite some protection in both countries, this species is still persecuted and large numbers are killed by unregulated hunting. Therefore, precise knowledge of their migratory routes is vital to ensure protection of necessary resources and sites throughout the year. We deployed five miniaturised satellite transmitters on adult Upland Geese to gather data about breeding, wintering and stopover sites all along their migratory routes. We aimed to identify important areas in the wintering and breeding grounds through kernel density analyses, and to match these sites along the migration routes with protected areas. Tracked birds exhibited different migration routes and reached different breeding grounds. Two individuals travelled from their wintering grounds in Buenos Aires province to their presumed breeding areas in southern Patagonia. However, we also found different stopover sites from another bird in northern Patagonia, from the ones postulated before, and evidence that some Upland Geese are not large-scale migrants. Our results highlight a considerable amount of plasticity in Upland Geese migratory behaviour. This study represents an essential first step towards identifying important stopover sites along the Upland Geese flyways and it also highlights the lack of protected habitats along most of their migration routes. [ABSTRACT FROM AUTHOR]

Beta-diversity, the measurement of community changes along gradients, is an important component of diversity, and is needed to understand how local communities are assembled from a regional pool. Although they have rarely been quantified, seasonal changes in species composition have important management implications, as they can hamper the representativeness of snapshot community studies. The present study thus maps bird seasonal changes in species composition (beta-diversity) across the contiguous USA, using weekly data from the eBird project. Besides management implications, this map also provides insights into the mechanisms driving seasonal beta-diversity, namely that it is mostly related to the annual temperature range and the size of the species pool. [ABSTRACT FROM AUTHOR]

Defining and identifying changes to seasonal ranges of migratory species is required for effective conservation. Historic sightings of migrating whooping cranes (Grus americana) have served as sole source of information to define a migration corridor in the Great Plains of North America (i.e., Canadian Prairies and United States Great Plains) for this endangered species. We updated this effort using past opportunistic sightings from 1942–2016 (n = 5,055) and more recent (2010–2016) location data from 58 telemetered birds (n = 4,423) to delineate migration corridors that included 50%, 75%, and 95% core areas. All migration corridors were well defined and relatively compact, with the 95% core corridor averaging 294 km wide, although it varied approximately ±40% in width from 170 km in central Texas to 407 km at the international border of the United States and Canada. Based on historic sightings and telemetry locations, we detected easterly movements in locations over time, primarily due to locations west of the median shifting east. This shift occurred from northern Oklahoma to central Saskatchewan at an average rate of 1.2 km/year (0.3–2.8 km/year). Associated with this directional shift was a decrease in distance of locations from the median in the same region averaging -0.7 km/year (-0.3–-1.3 km/year), suggesting a modest narrowing of the migration corridor. Changes in the corridor over the past 8 decades suggest that agencies and organizations interested in recovery of this species may need to modify where conservation and recovery actions occur. Whooping cranes showed apparent plasticity in their migratory behavior, which likely has been necessary for persistence of a wetland-dependent species migrating through the drought-prone Great Plains. Behavioral flexibility will be useful for whooping cranes to continue recovery in a future of uncertain climate and land use changes throughout their annual range. [ABSTRACT FROM AUTHOR]

How does agility evolve? This question is challenging because natural movement has many degrees of freedom and can be influenced by multiple traits. We used computer vision to record thousands of translations, rotations, and turns from more than 200 hummingbirds from 25 species, revealing that distinct performance metrics are correlated and that species diverge in their maneuvering style. Our analysis demonstrates that the enhanced maneuverability of larger species is explained by their proportionately greater muscle capacity and lower wing loading. Fast acceleration maneuvers evolve by recruiting changes in muscle capacity, whereas fast rotations and sharp turns evolve by recruiting changes in wing morphology. Both species and individuals use turns that play to their strengths. These results demonstrate how both skill and biomechanical traits shape maneuvering behavior. [ABSTRACT FROM AUTHOR]

The seasonal phenology of latitudinal movements is one of the key life-history traits of migratory birds. We used quantile regression to examine long-term changes in the timing of spring and autumn migration in 5 species of migratory passerine birds captured at a banding station in northern California, USA, over a 22 yr period from 1987 to 2008. Our 5 study species included 3 short-distance migrants, Pacific-slope Flycatcher [Empidonax difficilis), Orange-crowned Warbler [Oreothlypis celata), and Wilson's Warbler [Cardellina pusilla); and 2 long-distance migrants, Swainson's Thrush [Catharus ustulatus) and Yellow Warbler [Setophaga petechia). Median timing of migration advanced in spring for 2 of the 5 species (--2.5 days decade-1) but was delayed during autumn migration for 3 of the species (+2.9 days decade-1). The duration of the migration period also became compressed in some species but more protracted in others. We tested whether annual variation in migration timing was related to 3 indices of regional climatic conditions: the Pacific-North American index, multivariate El Niño-Southern Oscillation index, and North Atlantic Oscillation index. Climate indices explained relatively little of the variation in migration timing (r² < 0.35), but advances in spring migration and delays in autumn migration were associated with warm, wet conditions during positive phases of the climate indices. The strongest effects of climatic conditions on migration timing were found among short-distance migrants, with the largest changes in timing due to variation in the El Niño-Southern Oscillation and Pacific-North American indices. Linkages between the timing of movements and climatic conditions indicate that passerine birds on the Pacific coast exhibit phenotypic plasticity in their migration timing, but future studies based on experimental methods are needed to test alternative ecological mechanisms. [ABSTRACT FROM AUTHOR]

Migratory birds move through multiple habitats and encounter a diverse suite of parasites. This raises concern overmigrants' role in transporting infectious disease between breeding andwintering grounds, and along migratory flyways. Trade-offs between flight and immune defenses could interfere with infected individuals' migratory timing and success, potentially affecting infection dynamics. However, experimental evidence that parasitic infection affects migratory preparation or timing remains scant. We hypothesized that birds encountering hematozoan parasites shortly before migration incur physical costs (reduced body condition) and behavioral costs (delayed migration), due to the infection itself and/or to the demands of mounting an immune response. We experimentally inoculated song sparrows (Melospiza melodia) with Plasmodium shortly before fall migration. We monitored infection and body composition for 2 weeks after inoculation, and used radiotelemetry to track timing of migratory departure for another 7 weeks after release. Inoculated individuals that resisted infection had lower lean mass 12 days post exposure, relative to controls and infected individuals. This suggests trade-offs between body composition and immune defenses that might reduce migration success of resistant individuals. Despite group differences in body composition prior to release, we did not detect significant differences in timing of migration departure several weeks later. Thus, malarial infection did not appear to incur detectable costs to body composition or to migratory timing, at least when exposure occurs several weeks before migration. This study is novel considering not only the costs of infection, but also the costs of resisting infection, in an experimental context. [ABSTRACT FROM AUTHOR]

Advancement in timing of important life history events for birds due to climate change presents conservation and monitoring challenges. Song and other vocal activity are strong indicators of avian phenology because they correspond to territorial defense and mate attraction during the breeding season. We combined data from 2 projects using point counts and automated sound recorders to survey passerines during the breeding season in northern California, USA (553 sites, 2009-2011). We used multi-species occupancy modeling to estimate how detection probability based on vocalizations varied over the course of the breeding season. We estimated dates of peak vocal activity, which we reasoned were indicative of reproductive phenology. We demonstrated a strong unimodal relationship between vocal activity and survey date for 8 focal species for which average detectability peaked on June 21 (90% CI: June 19-June 22). Although we found no difference in peak dates of average detectability for migrants vs. residents, the variability of this estimate was lowest for Neotropical migrants compared to residents and elevational migrants. This finding supports previous research suggesting that long-distance migrants may be less flexible in adapting their phenology and more vulnerable to climate change. For an 80% power standard, we found that repeating our level of survey effort on an annual basis would allow detection of an advancement of average peak vocal activity by as small as 2.2 days over 10 yr for the focal species. We could detect smaller average shifts of 0.8 day decade-1 for this group or 1.6 days decade-1 for all passerines over 20 yr. Monitoring vocal phenology of birds through occupancy modeling of survey data from the breeding season is an efficient approach to assessing climate change impacts because species occupancies and measures of communitylevel diversity can be simultaneously estimated. [ABSTRACT FROM AUTHOR]

In the present study, we analyzed 173 spectrograms of acoustic signals of Redwings Turdus iliacus. These were issued during diurnal and nocturnalmigratory flight and also during feeding, when resting and before take-off at daytime stopovers.During nocturnal and diurnal migration flights and daytime stopovers, Redwings use a single type of signal, a long tsii. It is classified as a species-specific attraction call. In flight Redwings emit shorter calls than during daytime stopovers.We did not find confirmation of the hypothesis that during nocturnalmigration in the absence of visual contact with each other, due to lowlight levels andmuch looser flocks in the course of daytimemigration,Redwingsemit longer signals with wider frequency spectrum than in the daytime. [ABSTRACT FROM AUTHOR]