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An editorial is presented on the nature of environmental values which are invariably drawn back to such descriptions and it seems reasonable to suggest, and there is some special link between concrete experience of nature and environmental values, and articles in this volume explore various aspects of that link. It expresses view that focus on restricted sets of features, such as those that prompt responses to pictures, are liable to miss important aspects of favored experience of nature.

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]

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]

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]

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]

Background: Predicting the consequences of continuing anthropogenic changes in the environment for migratory behaviours such as phenology remains a major challenge. Predictions remain particularly difficult, because our knowledge is based on studies from single-snapshot observations at specific stopover sites along birds' migration routes. However, a general understanding on how birds react to prevailing environmental conditions, e.g. their 'phenotypic reaction norm', throughout the annual cycle and along their entire migration routes is required to fully understand how migratory birds respond to rapid environmental change. Results: Here, we provide direct evidence that northern wheatears (Oenanthe oenanthe) from a breeding population in Alaska adjusted their probability to resume migration as well as the distance covered per night, i.e. travel speed, to large-scale environmental conditions experienced along their 15,000 km migratory route on both northwards and southwards migrations. These adjustments were found to be flexible in space and time. At the beginning of autumn migration, northern wheatears showed high departure probabilities and high travel speeds at low surface air temperatures, while far away from Alaska both traits decreased with increasing air temperatures. In spring, northern wheatears increasingly exploited flow assistance with season, which is likely a behavioural adjustment to speed up migration by increasing the distance travelled per night. Furthermore, the variation in total stopover duration but not in travel speed had a significant effect on the total speed of migration, indicating the prime importance of total stopover duration in the overall phenology of bird migration. Conclusion: Northern wheatears from Alaska provide evidence that the phenotypic reaction norm to a set of environmental conditions cannot be generalized to universal and persistent behavioural reaction pattern across entire migratory pathways. This highlights the importance of full annual-cycle studies on migratory birds to better understand their response to the environment. Understanding the mechanisms behind phenotypic plasticity during migration is particularly important in the assessment of whether birds can keep pace with the potentially increasing phenological mismatches observed on the breeding grounds. [ABSTRACT FROM AUTHOR]

The East Asian-Australian Flyway spans from north Asia to Australia and is the world's richest birds' flyway because it involves > 40% of global migratory bird species. However, information is lacking on individual migratory routes and non-breeding grounds for small land birds using this flyway. Here, we present the first migration tracks of the songbird Stejneger's stonechat Saxicola stejnegeri from this part of the world using light-level geolocators. This species depends on grasslands during the entire annual cycle and was captured and equipped with tracking devices in Hokkaido, northern Japan. All individuals traveled through southern Primorye or eastern Heilongjiang (Russia/China) before flying southward via central China toward their major non-breeding grounds in southeast Asia (China, Laos, Cambodia, Thailand, and Vietnam). Individual stonechats spent 42-70 d en route during their autumn migration. Both the major non-breeding grounds and the stopover sites are likely to pose challenges to the persistence of this species, because these habitats are currently degraded and will likely be lost in the near future due to intensified agriculture and the establishment of permanent croplands. Moreover, the areas used by Stejneger's stonechat during migration largely overlapped with illegal trapping areas in northeastern China. [ABSTRACT FROM AUTHOR]

We studied the temporal-spatial distribution of Common Terns Sterna hirundo along the East Atlantic Flyway. In 2009 and 2010 experienced adults from a colony on the German North Sea coast were tagged with geolocators recording light intensity and saltwater contact. Main objectives were the inter-individual temporal-spatial variation of migration routes and wintering areas, wintering site fidelity, and time spent at sea across the annual cycle. Geolocators had no effects on various traits of breeders, but their reproductive output suffered from egg breakage. This can be avoided by artificially incubating the eggs. Twelve routes of nine individuals were tracked. Transponder readings at the breeding site showed that birds left the colony 4 weeks before starting autumn migration. In spring and autumn, Common Terns stopped over around the Canary Islands. Main wintering distribution was the upwelling seas alongside the West African coast and similar between years, but different among individuals. Three females wintered further north and more offshore than six males. Pair mates wintered at different locations. Spring migration was longer (56 ± 8 days) than autumn migration (37 ± 17 days). During both migration and wintering the terns spent more time on salt water than during breeding and post-breeding. In most individuals saltwater contact was higher during the day than at night, reduced at sunrise and sunset likely due to foraging, and peaked about noon possibly related to resting or thermoregulation. Detailed ecological and behavioral studies of common terns during wintering are needed to clarify the results based on geolocators. [ABSTRACT FROM AUTHOR]

Migratory birds use both geomagnetic and celestial cues to select and maintain their seasonally appropriate migratory direction. The integration of the different compass cues is still poorly understood. Previous cue-conflict experiments suggested that Pied Flycatchers Ficedula hypoleuca did not recalibrate their magnetic compass against the polarization pattern at twilight, but the available evidence is problematic given the high variability of birds' directional preferences. We performed a new set of cue-conflict experiments where (1) we modified the protocol in order to try to reduce scatter of data and (2) we integrated the results of two experimental approaches, i.e. orientation cages and releases of radio-tagged birds. Pied Flycatchers were tested in Emlen funnels without access to celestial cues before and after being exposed to conflicting visual and geomagnetic information. After the second test, birds were equipped with radio-transmitters and followed until the vanishing of the radio signal. Contrary to previous experiments, our data showed a general dominance of celestial cues: polarized light sun-related pattern in captive birds tested without access to stars and stellar dominance in free-flying birds released under a starry sky at night-time. These results underline the importance of experimental protocols when testing ways in which birds integrate their compass systems. [ABSTRACT FROM AUTHOR]

Encounters of Thalasseus maximus (Royal Terns) (n = 1387) banded as chicks in South Carolina were used to expand our knowledge regarding winter and migration sites of immature and mature birds, to identify causes of mortality, and to examine natal-site fidelity. Ages of encountered terns ranged from zero (less than one year old) to 27 years old. Mortality was highest in the first year of life. The majority of the encounters (64%, n = 879) were in Florida. Banded birds were also observed outside the US as far west as the Gulf coast of Mexico, east to Guyana, and south to Peru. Royal Terns appear to delay their first migration from winter grounds to breeding sites until the fourth summer. The vast majority of encounters (92%, n = 1275) were due to mortalities; the remaining 8% (n = 112) were of live terns encountered by resighting or capturing. In total, 35% (n = 485) of live or dead encounters were directly attributed to human activities, including entanglement in fishing gear (recorded as late as 1991) and shooting (recorded as late as 1980). [ABSTRACT FROM AUTHOR]

The article discusses the results of a review of observational and tracking data on the migration routes of Long-tailed Skuas in the spring season around and across Great Britain. A summary of the record overland movements of this bird species in spring 2013 including in Scotland, Iceland and North Atlantic is presented. The influence of conserve energy and response to weather conditions on the overland movements of birds are discussed. Record of east-coast sightings are provided.

Avian influenza virus (AIV) in wild birds has been of increasing interest over the last decade due to the emergence of AIVs that cause significant disease and mortality in both poultry and humans. While research clearly demonstrates that AIVs can move across the Pacific or Atlantic Ocean, there has been no data to support the mechanism of how this occurs. In spring and autumn of 2010 and autumn of 2011 we obtained cloacal swab samples from 1078 waterfowl, gulls, and shorebirds of various species in southwest and west Iceland and tested them for AIV. From these, we isolated and fully sequenced the genomes of 29 AIVs from wild caught gulls (Charadriiformes) and waterfowl (Anseriformes) in Iceland. We detected viruses that were entirely (8 of 8 genomic segments) of American lineage, viruses that were entirely of Eurasian lineage, and viruses with mixed American-Eurasian lineage. Prior to this work only 2 AIVs had been reported from wild birds in Iceland and only the sequence from one segment was available in GenBank. This is the first report of finding AIVs of entirely American lineage and Eurasian lineage, as well as reassortant viruses, together in the same geographic location. Our study demonstrates the importance of the North Atlantic as a corridor for the movement of AIVs between Europe and North America. [ABSTRACT FROM AUTHOR]

The article examines the accepted records of the arrival routes and occurrence of North American landbirds in Great Britain from 1958 to 2012. Records of bird migration were compared with Azores and Iceland, wherein 95 per cent of birds arrived in autumn while 31 per cent arrived in spring. Red-eyed Vireo was the bird species that visited most the country.

The migration rate of Nearctic-Neotropic songbirds is expected to be influenced by whether the route is around or across migration barriers such as the Gulf of Mexico. To examine factors that influence fall migration strategies, we used light-level geolocators to track the journeys of 91 Purple Martins (Progne subis) originating from breeding colonies across the eastern range of the species. We expected individuals that crossed the Gulf of Mexico to have slower migration rates, and more stopover days in Central America to refuel after the crossing, than birds that took routes around the gulf. Owing to expected variability in conditions experienced by individuals en route, we anticipated that departure date would be a poor predictor of arrival date within and among populations. Despite widely separated breeding origins, one-way journeys of >7,000 km, and high variability in departure dates and routes, individuals showed a strikingly similar fall migration strategy. Fall migration featured a rapid (450 km day-1) initial migration covering ≧2,000 km. followed by prolonged stopovers and a slower rate of travel before the birds continued to South America. Contrary to predictions, route explained little of the variation in the overall migration rate or the rate to Central America. Stopover duration in Central America was unrelated to whether birds crossed or circumnavigated the Gulf of Mexico. As expected, breeding location (primarily longitude) was the strongest predictor of the routes that birds took at this barrier. Within-breeding-region departure date alone predicted much of the variation in arrival date at the first winter roost, but route was not a significant factor. Our results reveal a consistent range-wide pattern in fall migration strategy, with route and migration timing predicting little of the variation in rate or stopover duration. [ABSTRACT FROM AUTHOR]

The article presents a study which reports on the status of the Baltic/Wadden Sea flyway Eider population, based on trends in breeding and wintering numbers throughout the region, with details on the changes in the sex ratio and proportion of young Eiders. It indicates a decline on the total numbers of breeding pairs and population nest on the flyway scale for the given monitoring period in 1991 to 2000 in Finland and Sweden. The authors believe that flyway population will experience further declines and recommend some population drivers to improve flyway-level monitoring and management of Eiders.

Stopover studies have concentrated so far mostly on mechanisms regulating the temporal organisation on the day-to-day level. Taking advantage of the small and isolated island of Helgoland in the North Sea, we investigated the stopover and departure behaviour of a nocturnal migrant by using radio telemetry. Special attention was paid particularly to nocturnal behaviour, their departure times within the night, and departure directions. Here, we show that Northern Wheatears, Oenanthe oenanthe, performed regularly nocturnal exploratory flights on nights before and on departure night, which might be a common behaviour of nocturnal migrants to evaluate meteorological conditions aloft prior to departure. We proposed that migrants being prepared for an endurance flight would depart early in the night within a short time window, whereas individuals departing with low fuel load would be less prone to take off early. Our data, however, could not support this hypothesis. In respect of the migratory direction, there was a significant correlation between departure direction and departure fuel load. Northern Wheatears with high departure fuel loads headed more towards the north than lean migrants, which departed mostly towards the nearest coastline, i.e. east to south. Thus, birds with high fuel loads showed their seasonally appropriate migratory direction irrespective of the ecological barrier ahead, whereas lean birds avoided this direction. To our knowledge, this is the first study that investigates the relationship of fuel load and departure direction in a free-flying songbird. [ABSTRACT FROM AUTHOR]

The article presents a study on the broad scale movements of juvenile songbirds prior to migration. The study used radio telemetry and the topographical characteristics of the study sites to assess four hypothesis including the beginning of migration, habitat optimization, and the selection of breeding territory. The result showed that the movement of Yellow-rumped Warbler (Dendroica coronata) was directed toward down river valleys while Balckpoll Warbler (D. striata) moved toward the southeast.

The article discusses a study conducted by the researchers Kira Delmore and Darren Irwin from the University of British Columbia, Vancouver, Canada to examine how hybrid young migratory songbirds display mixed-up migratory routes in response to varied set of genetic directions, much to their own detriment, published in the scientific journal "Ecology Letters." The study indicates a role of migration in speciation and provides evidence for the genetic control of migratory behavior in songbirds.

There have been, over the years, conflicting statements by various authors regarding the altitude at which Quail Coturnix coturnix migrate. [ABSTRACT FROM AUTHOR]