Migratory Birds Research Papers - Academia.edu (original) (raw)

2025, Archaeology, Ethnology & Anthropology of Eurasia. Vol. 53. No. 2. P. 116-125

Data on the distribution of folklore and mythological motifs in the New World are analyzed. Their areas agree with the idea that early migrants moved along the Pacifi c coast of North America. The Columbian Plateau with the adjacent part of the coast could have been a hub whence people dispersed to the south, southeast, and east. The transfer of cultural elements along the Mackenzie Corridor is supported neither by the distribution of mythological episodes and images nor by archaeological evidence (the latter suggests an oppositely directed migration in the Terminal Pleistocene-from the main territory of the U.S. to Alaska). North American and South American narrative episodes and mythological motifs are separated by a huge geographic gap: Many migrant populations seem to have rapidly reached South America, leaving certain groups behind. While in America distribution areas of motifs follow recognizable patterns, in the Old World the same motifs are scattered from Europe to the Pacifi c, which may attest to the heterogeneity of the Beringian population immediately before the migration to the New World. Besides the main (early) episode of peopling, data on the areal distribution of motifs reveal three or four later episodes.

2025, PLOS Neglected Tropical Diseases

Borrelia miyamotoi is a relapsing fever spirochete that shares the same vector as Lyme disease causing Borrelia. This epidemiological study of B. miyamotoi was conducted in rodent reservoirs, tick vectors and human populations simultaneously. A total of 640 rodents and 43 ticks were collected from Phop Phra district, Tak province, Thailand. The prevalence rate for all Borrelia species was 2.3% and for B. miyamotoi was 1.1% in the rodent population, while the prevalence rate was quite high in ticks collected from rodents with an infection rate of 14.5% (95% CI: 6.3–27.6%). Borrelia miyamotoi was detected in Ixodes granulatus collected from Mus caroli and Berylmys bowersi, and was also detected in several rodent species (Bandicota indica, Mus spp., and Leopoldamys sabanus) that live in a cultivated land, increasing the risk of human exposure. Phylogenetic analysis revealed that the B. miyamotoi isolates detected in rodents and I. granulatus ticks in this study were similar to isolates...

2025, Magyar vízivad közlemények

2025, Oikos

In a periodically changing environment it is important for animals to properly time the major events of their life in order to maximise their lifetime fitness. For a non‐migratory bird the timing of breeding and moult are thought to be the most crucial. We develop a state‐dependent optimal annual routine model that incorporates explicit density dependence in the food supply. In the model the birds’ decisions depend on the time of year, their energy reserves, breeding status, experience, and the quality of two types of feathers (outer and inner primaries). Our model predicts that, under a seasonal environment, feathers with large effects on flight ability, higher abrasion rate and lower energetic cost of moult should be moulted closer to the winter (i.e. later) than those with the opposite attributes. Therefore, we argue that the sequence of moult may be an adaptive response to the problem of optimal timing of moult of differing feathers within the same feather tract. The model also ...

2025, Philosophical Transactions of the Royal Society B: Biological Sciences

The annual life cycle of many birds includes breeding, moult and migration. All these processes are time and energy consuming and the extent of investment in any one may compromise the others. The output from breeding is of course the ultimate goal for all birds, while the investment in moult and migration should be selected so that lifetime fitness is maximized. In particular, long-distance migrants breeding at high latitudes face severe time pressures, which is a probable reason why natural selection has evolved efficient behaviours, physiological and morphological adaptations allowing the maximum possible migration speed. Optimal migration theory commonly assumes time minimization as an overall strategy, but the minimization of energy cost and predation risk may also be involved. Based on these assumptions, it is possible to derive adaptive behaviours such as when and at which fuel load a stopover site should be abandoned. I review some core components of optimal migration theory...

2025, Ticks and tick-borne diseases

Seasonal migration of passerine birds between temperate North America and tropical Central and South America is an ecological phenomenon. Migration of birds has been associated with the introduction of ectoparasites like ticks or tick-borne pathogens across the avian migration routes. In this study, the microbial diversity was determined in the ticks and bird DNA samples using 454 pyrosequencing of bacterial 16S rRNA gene. Tick DNA samples showed the dominance of genera Lactococcus, Francisella, Raoultella, Wolbachia and Rickettsia across all the ticks, but birds DNA did not share common microbial diversity with ticks. Furthermore, "Candidatus Rickettsia amblyommii" infection in the 91 ticks collected off the songbirds was also quantified by qPCR assay. Interestingly, "Candidatus R. amblyommii" was tested positive in 24 ticks (26% infection), and infection varied from as low as three copies to thousands of copies, but bird blood samples showed no amplification. O...

2025, MULTIPLE AUTHORS (!); first author: Attila Bende; Dynamics of Sex and Age Correlation of Eurasian Woodcock (Scolopax rusticola L.) During Spring Migration in Hungary

AUTHORS: Attila Bende, Sándor Faragó, Richárd László, Viktória Csanády, István Fekete, Tibor Pecsics and László Bozó Our research provides detailed insights into the migratory patterns of the Eurasian Woodcock. By focusing on the... more

2025, Nuestras Aves

Members of the Furnariidae family generally eat insects and small vertebrates. However, recent reports suggest that they can also eat fruits. Here we present the first record of frugivory of the Narrow-billed Woodcreeper (Lepidocolaptes angustirostris) on Scutia buxifolia, a woody species from the Humid Chaco of Santa Fe province, Argentina, is presented. Ingest was probed by the presence of 12 seeds in the feaces of a specimen.

2025, The Migrant

Collisions with windows are a major source of mortality for birds and are regarded as
a serious threat to their populations. I have been monitoring bird casualties around 11
buildings on the campus of the University of Tennessee at Chattanooga for the past 20
years, documenting numbers of individuals and species killed or injured from striking
windows. I have tallied 854 casualties comprising 76 species. Most casualties occur during
migration, especially in the fall, and four buildings account for 90% of casualties. Common
Yellowthroat was the most frequently detected species and accounted for nearly 10% of all
casualties found.

2025, Cities and the Environment

Many North American landbirds undergo biannual migrations, which are energetically costly. Quality stopover sites are crucial to avian survival, as they provide opportunities to quickly replenish fat stores, rest, and avoid predation. One component of habitat quality that is often overlooked is the level of pedestrian activity, which birds may interpret as a predatory threat. If intrusion levels are high, birds will flush repeatedly and may not adequately restore energy reserves, which hinders successful migration. We compared body mass index between birds at different intrusion levels, testing the hypothesis that birds near continuous intrusion will be in poorer condition. Results between migratory guilds indicate longdistance migrants were in poorer condition in areas with high pedestrian activity. In contrast, resident species captured in high activity areas were in better condition than those captured in areas with lower activity. Since Neotropical migrants show increased sensitivity to human presence, conservation measures should focus on reducing pedestrian activity for quality stopover habitats.

2025

Military lands and waters may be particularly valuable for migrating birds requiring stopover habitat to rest and refuel en route to very distant seasonal ranges. Recent developments in radar technology have provided powerful tools for investigating on a broad scale migrant use of military installations; thus providing an opportunity to improve both conservation and flight safety measures. In this study, spring and fall migrant use of 40 military installations across the United States were qualitatively investigated. These times of year were selected since they are the periods when BASH is of most concern. Migratory patterns on three installations (Eglin Air Force Base, FL; Ft. Polk, LA; and Yuma Proving Ground, AZ) were then closely examined and migration forecast models for those locations were developed with the goal of providing a tool for reducing the probability of collisions between birds and military aircraft. A comparison was also made between radar estimates of migrant densities aloft during exodus events and more traditional ground-based surveys to evaluate the effectiveness of estimating migrant abundance in stopover habitat with radar data. At Fort Polk, movement ecology and migrant-habitat relations of the Red-eyed Vireo were investigated during migratory stopover. Lastly, migrant use of diverse riparian habitats was compared along water courses near the Yuma Proving Ground. Results indicated that approximately half of the installations examined with radar data contained migrant stopover "hotspots," reaffirming the fact that military installations are important to migrating birds. Interestingly, migrant abundances, and species turnover as estimated by ground-based surveys, were found to poorly reflect migrant densities estimated with radar data. Migrant abundance, species richness, and community composition were all also found to be influenced by riparian vegetation composition. This information collectively suggested that radar data can be used to identify migratory hotspots on military installations and improve flight safety on installations with an aviation mission. However, radar data may not be sufficient to distinguish fine-scale differences in habitat use by migrants within an installation's boundaries. The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR.

2025, Journal of Experimental Biology

SUMMARYBirds adjust their flight behaviour to the physical properties of the air. Lift and drag, the two major properties in aerodynamics, are highly dependent on air density. With decreasing air density drag is reduced and lift per wingbeat decreases. According to flight mechanical theory, wingbeat frequency and air speed should increase with decreasing air density, i.e. increasing flight altitude. Although wind tunnel experiments have shed light on many aspects of avian flight, the effect of air density remained ambiguous, because air density could not be adjusted in wind tunnels, until now. By means of radar we recorded tracks of several thousand free-flying individual birds during nocturnal migration. From these tracks we derived wingbeat frequencies and air speeds covering air densities from 0.84 kg m–3 to 1.13 kg m–3, corresponding to an altitudinal range of about 3000 m. We demonstrate here with this sample of nocturnal migrants that: (1)wingbeat frequency decreases with air ...

2025, The Wilson Journal of Ornithology

We analyzed changes in abundance of terrestrial birds on St. John, U.S. Virgin Islands, for a 32 year period during which 3 major hurricanes occurred. Using 1987 as a baseline year, because it followed a 27 year hiatus when no major hurricanes hit the island, we assessed the impact of hurricanes on vegetation structure and bird populations. Bird abundance was determined for 25 m radius circular plots that were surveyed each year of the study along the same transects. Percent cover of trees, shrubs, and herbs was measured in each plot in 1987, 1990, and 2019. All of the survey plots were in moist forest or dry woodland in Virgin Islands National Park. Of 13 common birds, 5 did not show marked and consistent declines in abundance following hurricanes even though the structure of vegetation on the island was heavily modified by storms. Three of these species are insectivores. Seven species declined or showed habitat shifts following Hurricane Hugo in 1989, but 5 of these populations subsequently increased and most recovered to close to their 1987 abundance during the 1990s. Six of these 7 species also declined or showed habitat shifts following Hurricanes Irma and Maria in 2017. The most marked declines in the aftermath of hurricanes in both 1989 and 2017 were for frugivores and nectarivores, especially hummingbirds. Most common bird species in Virgin Islands National Park were either resistant to the effects of severe hurricanes or resilient in the decade following a hurricane. However, more research is needed to assess the status of vulnerable species such as hummingbirds and rare resident species (Bridled Quail-Dove [Geotrygon mystacea] and Puerto Rican Flycatcher [Myiarchus antillarum]).

2025

During the summer of 1953 William Niering and Richard Goodwin initiated a study of the birds and vegetation in the Connecticut College Arboretum in New London. They surveyed plants and counted singing birds in two adjacent study sites: a shrubby old field that had been abandoned a few years previously, and an old, but storm-damaged, oak-hemlock forest. Their intent was to monitor the old field as it changed to a thicket and then to a young forest. The oakhemlock forest would serve as a relatively stable "control," a baseline for comparison. How long would it take before these two distinctly different sites shared similar arrays of plants and animals? Changes in the birdlife of the old field were predictably dramatic. The Ring-necked Pheasants, American Goldfinches, and Song Sparrows of the open grassland were replaced by Brown Thrashers, Prairie Warblers, Yellow-breasted Chats, and other thicket species, which in turn disappeared as the young forest was colonized by Black-capped Chickadees, Wood Thrushes, and Red-eyed Vireos (Askins 1990). Unexpectedly, the bird community of the mature forest displayed changes that were nearly as dramatic. By the early 1970s many voices had disappeared from the morning chorus of early summer in the forest. Eastern Wood-Pewee, Canada Warbler, American Redstart, and Black-throated Green Warbler were gone; and Red-eyed Vireo and Hooded Warbler had declined precipitously ). The forest had become more mature as the tree canopy closed, creating what appeared to be a more'favorable habitat for at least some of these forest bird species, but they declined nonetheless. This change was particularly alarming because it paralleled changes at many other forest sites in eastern North America. Many of the same species had declined at four sites near Washington, D.C., two sites in northern New Jersey, and one site in upstate New York . A particularly severe collapse in the diversity of forest birds was recorded at Greenbrook Sanctuary, a preserve on the Palisades above the Hudson River. Between the late 1940s and the 1980s, the following species disappeared from this study site: Eastern Wood-Pewee, Yellow-throated Vireo, Black-throated Green Warbler, American Redstart, Ovenbird, and Hooded Warbler (Serrao 1985). Most of the species that declined at Greenbrook Sanctuary and the other sites shared two characteristics: they are forest specialists (species that normally nest in the interior of forests, away from open habitats) and neotropical migrants (species that nest in the North American temperate zone and winter in the tropics).

2025, Vector-Borne and Zoonotic Diseases

We sought to elucidate the role of migratory birds in transmission of H5N1 in an enzoonotic area. Resident, captive, and migratory birds were sampled at five sites in Java, Indonesia. Mist nets were used to trap birds. Birds were identified to species. RNA was extracted from swabs and reverse transcriptase polymerase chain reaction (RT-PCR) conducted for the HA and M genes of H5N1. Antibodies were detected by enzyme-linked immunosorbent assay and hemagglutination inhibition test. Between October 2006 and September 2007, a total of 4,067 captive, resident, and migratory birds comprising 98 species in 23 genera were sampled. The most commonly collected birds were the common sandpiper (6% of total), striated heron (3%), and the domestic chicken (14%). The overall prevalence of H5N1 antibodies was 5.3%. A significantly higher percentage of captive birds (16.1%) showed antibody evidence of H5N1 exposure when compared to migratory or resident birds. The greatest number of seropositive birds in each category were Muschovy duck (captive), striated heron (resident), and the Pacific golden plover (migratory). Seven apparently well captive birds yielded molecular evidence of H5N1 infection. Following amplification, the HA, NA, and M genes were analyzed. Phylogenetic analysis of the HA gene showed that the isolates were 97% similar to EU124153.1 A/chicken/West Java/Garut May 2006, an isolate obtained in a similar region of West Java. While no known markers of neuraminidase inhibitor resistance were found within the NA gene, M segment analysis revealed the V27A mutation known to confer resistance to adamantanes. Our results demonstrate moderate serologic evidence of H5N1 infection in captive birds, sampled in five sites in Java, Indonesia, but only occasional infection in resident and migratory birds. These data imply that in an enzoonotic region of Indonesia the role of migratory birds in transmission of H5N1 is limited.

2025

s: Oral presentations What have we learnt from the Atlas and Virtual Museum projects?

2025, Science Vision

Aquatic avifauna are an important bio-indicator of an ecosystem changes. Mizoram, one of the northeastern states of India, lies in one of the richest biodiversity hotspots of the world. Along its water bodies, it is home to several species of resident birds, and is also a temporary home for migrating birds in different seasons. These resident and migratory avifauna form an important component of most wetland ecosystems, as they are vital components of the food webs. While only the Tamdil and Palak Lake are recognized as wetlands, there are several rivers and smaller water bodies around which aquatic avifauna exist. However, official records comprise of about 14 species of waterbirds belonging to 6 orders and 8 families. Of these, Anatidae, Charadriidae, Scolopacidae, Anhingidae, and Podicipedidae are represented by one species each, while the Ardeidae are represented by four species. Among the 14 species reported so far, two species of the Order Pelicaniformes, namely Anhinga melanogaster (Family Anhingidae) and Ardea insignis (Family Ardeidae) are highly endangered. However, detailed studies are wanting and, while there are sporadic reports of sightings on social media, there is a need for a more comprehensive study of the diversity and seasonal variations of aquatic avifauna around the different water bodies of the state of Mizoram.

2025, Journal of Ornithology

Glucocorticoids promote the mobilization of energy stores and they may facilitate the expression of energetically expensive functions. Early arrival on the breeding grounds in migratory species and territorial competition are energetically demanding activities that may be supported by elevated baseline glucocorticoid levels. Here, we evaluated the associations between the baseline levels of excreted corticosterone (CORT) metabolites of male Pied Flycatchers (Ficedula hypoleuca) just after arriving on their breeding area and timing of arrival, considering ornamental traits indicative of social status, like forehead patch size and black plumage coloration, as well as heat shock protein levels (HSP60). We observed a positive association of CORT metabolites with HSP60 levels, which are synthesized under several environmental challenges affecting cell homeostasis. Our data showed a negative association between arrival date and CORT metabolite levels, possibly as a result of the higher energetic demands imposed by the hard environmental conditions experienced at the time of an early arrival after migration. We observed a negative relationship of forehead patch dimensions and CORT metabolite levels, suggesting that dominance is associated with low baseline CORT metabolites. Also, males that expressed a higher degree of territorial behaviour when exposed to a playback song of a conspecific at their nest-box showed higher CORT metabolites upon arrival than males that expressed a lower degree of territorial behavior. This may indicate that elevated baseline CORT metabolite levels may facilitate an intense territorial competition in males. Thus, male-male competition may be a factor affecting observed baseline glucocorticoid levels in migratory birds.

2025

Northern Kazakhstan and adjoining areas of Russia have vitally important autumn staging sites for arctic breeding geese, especially for the globally threatened Lesser White-fronted Goose Anser erythropus (LWfG) and Red-breasted Goose Branta ruficollis (RbG). Part of the Fennoscandian and the entire Western Main subpopulations of LWfG and the global population of RbGs are believed to stage there, which facilitates obtaining up-to-date population estimates for these species. A total of 80 lakes were surveyed across four survey areas in autumn 2016, recording more than 1.2 million geese in the region. Greater White-fronted Geese Anser albifrons (GWfG) were the most abundant with an estimated c. 890,000 birds, with counts of c. 250,000 Greylag Geese Anser anser, c. 53,000 Ruddy Shelduck Tadorna ferruginea , c. 39,100 RbG and c. 32,000 LWfG also recorded during the surveys. Based on a priori lake classification for both LWfG and RbG, to stratify survey lakes in order to generate total po...

2025

Roadside point counts are generally used for large surveys to increase the number of samples. We examined differences in species detected from roadside versus off-road (200-m and 400-m) point counts in the Shenandoah National Park. We also compared the list of species detected in the first 3 minutes to those detected in 10 minutes for potential species biases. Results from 81 paired roadside and off-road counts indicated that roadside counts had higher numbers of several edge species but did not have lower numbers of nonedge forest species. More individuals and species were detected from roadside points because of this increase in edge species. Sixtyfive percent of the species detected in 10 minutes were recorded in the first 3 minutes.

2025, Systematic and Applied Acarology

In 2008, tick surveillance of migratory birds was conducted on Hong-do (Hong Island), Jeollanam Province, Republic of Korea. Seventy-seven ticks representing two genera and four species-Haemaphysalis flava Neumann (21 ticks), Haemaphysalis ornithophila Hoogstraal & Kohls (2), Ixodes nipponensis Kitaoka & Saito (3), and Ixodes turdus Nakatsuji (51)-were collected from 12 species of birds belonging to nine genera. Two male H. ornithophila, an uncommonly collected tick, were removed from a scaly thrush, Zoothera dauma (Latham), on Hong-do. Haemaphysalis ornithophila is a Southeast Asian species that was transported to Korea during the spring migration of Z. dauma to its breeding grounds in Russia. This first report of H. ornithophila from Korea has implications for the introduction of exotic tick species and their pathogens on migratory birds.

2025, Environmental …

Because of their intense vegetation and the fact that they include areas of coastline, deltas situated in the vicinity of big cities are areas of greet attraction for people who wish to get away from in a crowded city. However, deltas, with their fertile soil and unique flora and fauna, need to be protected. In order for the use of such areas to be planned in a sustainable way by local authorities, there is a need for detailed data about these regions. In this study, the changes in land use of the Balçova Delta, which is to the immediate west of Turkey's third largest city Izmir, from 1957 up to the present day, were investigated. In the study, using aerial photographs taken in 1957, 1976 and 1995 and an IKONOS satellite image from the year 2005, the natural and cultural characteristics of the region and changes in the coastline were determined spatially. Through this study, which aimed to reveal the characteristics of the areas of land already lost as well as the types of land use in the Balçova delta and to determine geographically the remaining areas in need of protection, local authorities were provided with the required data support. Balçova consists of flat and fertile wetland with mainly citrus-fruit orchards and flower-producing green houses. The marsh and lagoon system situated in the coastal areas of the delta provides a habitat for wild life, in particular birds. In the Balçova Delta, which provides feeding and resting for migratory birds, freshwater sources are of vital importance for fauna and flora. The settlement area, which in 1957 was 182 ha, increased 11-fold up to the year 2005 when it reached 2,141 ha. On the other hand, great losses were determined in farming land, olive groves, forest and in the marsh and lagoon system. This unsystematic and rapid urbanization occurring in the study region is not only causing the loss of important agricultural land and wetland, but also lasting water and soil pollution.

2025, Animal Behaviour

Migratory birds replenishing their fuel stores have to decide when to leave their stopover site for the next flight bout. We studied whether the decision to leave a stopover site depends on wind and rain conditions. From captureerecapture data of 1153 European robins collected during three autumns at a stopover site in Switzerland, we estimated the daily emigration probability with a newly developed multistate captureerecapture model that accounts for the occurrence of transients. We tested whether the variation in the daily emigration probabilities can be explained by wind speed, wind direction (both on the ground and 300 m above ground) or rain. Variation in emigration probability was largely explained by variation in wind at 300 m and rain. The emigration probability was highest (0.5) during nights with no or weak (!1.5 m/s) winds at 300 m and no rain, intermediate (0.15e0.2) on nights without rain and with medium wind (O1.5 m/s), and on nights with weak winds (!1.5 m/s) and rain; and almost zero during nights with rain and strong winds at 300 m. Wind direction at 300 m and wind conditions (speed and direction) on the ground had no influence on departure decision. We suggest that birds may consider cues other than wind speed at ground level to predict wind speed at higher altitudes, and that they consider wind direction only when aloft by selecting an optimal flight altitude. Wind speed aloft and rain appeared to be significant factors that synchronize bird migration spatially and temporally.

2025

Birds are well known for construction of various kinds of nests. It is an instinct behaviour. For protection against rain, environmental temperature difference, to care the brood, a part of breeding process birds construct nests. Nest structure, designs and materials used in nest construction are species specific. The specificity also found in nesting site selection, avoidance of predation risk and easy way to rescue from the nest. Present study on ten species of local birds and their nest structure, nest material used reveals that 54.40 % locally available material was used by these species that includes plant materials mainly. The synthetic materials, soil, silt, mud and the materials of animal origin like human hair, spider net threads, and dropped feathers of birds were used in nest construction. Most diverse selection of nest material was by Indian Common Mayna whereas least type of material used by Baya weaver. Residential buildings and office buildings, buildings of education centres in the University campus were effectively used by the birds in non nesting period as shelter. The brilliance and plasticity of birds was remarkable for survival of fittest with existing conditions. Detailed study on each species nest was recommended to understand and plan for their conservational importance.

2025, Journal of Sustainability and Environmental Management (JOSEM)

Freshwater snail population numbers and their ecological significance need to be better understood. This study aimed to measure snail abundance in Biltongi-Narayanparabeel in the Natore district. The objective was to establish the population density of snails using the CMR (Capture-Mark-Recapture) method in four sections of the Biltongi-Narayanpara beel between August 2022 and February 2023. Snail samples were collected from four sampling sites, each located in different areas: one near agricultural land, one in the shallows, and one in the middle of the deepest part of the beel. The plot with the highest overall mean population density in terms of CMR for the presence of snails was plot 3 (33.25 ± 2.75), while the field with the lowest density was plot 4(22.75 ± 2.22). The biomass showed only slight variations across the different habitat categories. This is likely due to the presence of many young snails in shallow areas, whereas young snails in nearby regions were nearly nonexistent.

2025

Migratory birds demonstrate remarkable temporal plasticity, adapting their circadian rhythms and sleep patterns to meet the demands of long-distance migration. This perspective explores how insights from avian temporal adaptations could inform novel research directions in human sleep and circadian medicine. Birds' ability to maintain precise temporal organization through multiple coordinated oscillators, particularly during migratory periods, provides a valuable framework for understanding circadian flexibility. Drawing from recent advances in avian chronobiology, we propose several research priorities for human applications, including biomarker-guided chronotherapy, circuit-specific interventions, and optimization of environmental cue timing. We explore how birds' sophisticated control of sleep architecture and metabolic regulation during migration might inspire new approaches to managing circadian disruptions in humans. Neuroimaging studies of human temporal adaptability, guided by avian insights, could reveal network-level mechanisms underlying circadian plasticity. Of particular interest is the parallel between avian unihemispheric sleep and human hemispheric asymmetry during sleep, suggesting the evolutionary conservation of adaptive sleep mechanisms. While acknowledging the fundamental differences between avian and human circadian systems, we outline specific research directions that could translate avian temporal adaptability principles into therapeutic strategies for circadian disorders. While these avian-inspired hypotheses require rigorous validation, and some may not prove viable, embracing creative exploration remains essential for advancing our understanding of human circadian biology and guiding the development of novel therapeutic approaches.

2025, Central European Journal of Biology

Global climate change has important impacts on animal life-cycles. One of the responses to global warming is an earlier arrival time of many migratory bird species. The first arrival date of the Nightingale (Luscinia megarhynchos) in Central Croatia was studied for the periods of 1901–1917 and 1991–2005. Data were derived from the first spring observations and first capture data. A statistically significant advance of 11 ± 1.4 days was recorded. The difference in the mean April temperature between two study periods was significant, while changes in NAO winter index were not significant. Adequate data from the beginning of the 20th century exist; however, recent studies were done on a relatively short-term basis. Therefore, the analysis of two discrete datasets may help to fill the gaps in the knowledge about the climate change response.

2025, Ornis Fennica

A. de Jong, L. Edenius, Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, S-901 83 Umeå, Sweden. * Corresponding author’s e-mail: adriaan.de.jong@slu.se J. Torniainen, Open Science Centre and Department of Biological and Environmental Science, P. O. Box 35, FI-40014 University of Jyväskylä, Finland O. G. Bourski, A.N. Severtsov Institute of Animal Ecology and Evolution RAS, Leninsky prospect 33, 119071 Moscow, Russia W. Heim, Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany

2025

The timing of moult in birds is thought to be constrained by physiological trade-offs. We studied barn swallows in central Spain to assess whether (a) body moult tends to be temporally separated from migration in adult and first-year birds, (b) it is related to an impaired fattening, and (c) its overlap with migration may involve adverse energetic effects. First-year swallows tended to moult early in the post-breeding period: the proportion of first-year birds in active moult was highest in July, and it decreased progressively until September. On the other hand, adult swallows tended to avoid moulting both in the post-breeding (July) and the migratory period (September), concentrating their moulting period in August. In all periods, swallows in active moult stored less fat than non-moulting ones, suggesting a faster depletion of energy resources by moulting birds. Swallows in active moult showed a better body condition -measured as body mass relative to body size and fat content -than nonmoulting ones before migration (coinciding with the periods of highest frequency of moulting individuals), but the opposite was found during autumn migration. Our results support the existence of a physiological trade-off between body moult and migration, which could have fitness consequences; thus, if these activities overlap it would impair migration performance of swallows.

2025, Behavioral Ecology and Sociobiology

Recent experiments exposing migratory birds to altered magnetic fields simulating geographical displacements have shown that the geomagnetic field acts as an external cue affecting migratory fuelling behaviour. This is the first study investigating fuel deposition in relation to geomagnetic cues in long-distance migrants using the western passage of the Mediterranean region. Juvenile wheatears (Oenanthe oenanthe) were exposed to a magnetically simulated autumn migration from southern Sweden to West Africa. Birds displaced parallel to the west of their natural migration route, simulating an unnatural flight over the Atlantic Ocean, increased their fuel deposition compared to birds experiencing a simulated migration along the natural route. These birds, on the other hand, showed relatively low fuel loads in agreement with earlier data on wheatears trapped during stopover. The experimental displacement to the west, corresponding to novel sites in the Atlantic Ocean, led to a simulated longer distance to the wintering area, probably explaining the observed larger fuel loads. Our data verify previous results suggesting that migratory birds use geomagnetic cues for fuelling decisions and, for the first time, show that birds, on their first migration, can use geomagnetic cues to compensate for a displacement outside their normal migratory route, by adjusting fuel deposition.

2025, The Journal of Experimental Biology

Recent studies have shown that migratory thrush nightingales (Luscinia luscinia) experimentally treated with multiple changes of the magnetic field simulating a journey to their target stopover area in northern Egypt, increased fuel deposition as expected in preparation to cross the Sahara desert. To investigate the significance of food intake on the body mass changes observed, in the work described here we analysed food intake of the nightingales under study in those earlier experiments. Furthermore, to study whether a single change in the magnetic field directly to northern Egypt is sufficient to provide information for fuelling decisions, we performed a new experiment, exposing thrush nightingales trapped in Sweden, directly to a magnetic field of northern Egypt. Our results show that an experimentally induced magnetic field of northern Egypt, close to the barrier crossing, triggers the same response in fuel deposition as experiments with multiple changes of the magnetic field simulating a migratory journey from Sweden to Egypt, suggesting that migratory birds do not require successive changes in field parameters to incorporate magnetic information into their migratory program. Furthermore, irrespective of experimental set up (single or multiple changes of the magnetic field parameters) increase in food intake seems to be the major reason for the observed increase in fuelling rate compared with control birds, suggesting that geomagnetic information might trigger hormonal changes in migratory birds enabling appropriate fuelling behaviour during migration.

2025, Proceedings of The Royal Society B: Biological Sciences

Bird migration requires high energy expenditure, and long-distance migrants accumulate fat for use as fuel during stopovers throughout their journey. Recent studies have shown that long-distance migratory birds, besides accumulating fat for use as fuel, also show adaptive phenotypic flexibility in several organs during migration. The migratory routes of many songbirds include stretches of sea and desert where fuelling is not possible. Large fuel loads increase flight costs and predation risk, therefore extensive fuelling should occur only immediately prior to crossing inhospitable zones. However, despite their crucial importance for the survival of migratory birds, both strategic refuelling decisions and variation in phenotypic flexibility during migration are not well understood. First-year thrush nightingales (Luscinia luscinia) caught in the early phase of the onset of autumn migration in southeast Sweden and exposed to a magnetic treatment simulating a migratory flight to northern Egypt increased more in fuel load than control birds. By contrast, birds trapped during the late phase of the onset of autumn migration accumulated a high fuel load irrespective of magnetic treatment. Furthermore, early birds increased less in flight-muscle size than birds trapped later in autumn. We suggest that the relative importance of endogenous and environmental factors in individual birds is affected by the time of season and by geographical area. When approaching a barrier, environmental cues may act irrespective of the endogenous time programme.

2025, Proceedings of The Royal Society B: Biological Sciences

Recent evaluations of both temporal and spatial precision in bird migration have called for external cues in addition to the inherited programme defining the migratory journey in terms of direction, distance and fuelling behaviour along the route. We used juvenile European robins (Erithacus rubecula) to study whether geomagnetic cues affect fuel deposition in a medium-distance migrant by simulating a migratory journey from southeast Sweden to the wintering area in southern Spain. In the late phase of the onset of autumn migration, robins exposed to the magnetic treatment attained a lower fuel load than control birds exposed to the ambient magnetic field of southeast Sweden. In contrast, robins captured in the early phase of the onset of autumn migration all showed low fuel deposition irrespective of experimental treatment. These results are, as expected, the inverse of what we have found in similar studies in a long-distance migrant, the thrush nightingale (Luscinia luscinia), indicating that the reaction in terms of fuelling behaviour to a simulated southward migration varies depending on the relevance for the species. Furthermore, we suggest that information from the geomagnetic field act as an important external cue overriding the seasonal effect on fuelling behaviour in migratory birds.

2025, Journal of Experimental Biology

SUMMARY Long-distance migrants regularly pass ecological barriers, like the Sahara desert, where extensive fuel loads are necessary for a successful crossing. A central question is how inexperienced migrants know when to put on extensive fuel loads. Beside the endogenous rhythm, external cues have been suggested to be important. Geomagnetic information has been shown to trigger changes in foraging behaviour and fuel deposition rate in migratory birds. The underlying mechanism for these adjustments, however, is not well understood. As the glucocorticoid hormone corticosterone is known to correlate with behaviour and physiology related to energy regulation in birds, we here investigated the effect of geomagnetic cues on circulating corticosterone levels in a long-distance migrant. Just as in earlier studies, juvenile thrush nightingales (Luscinia luscinia) caught during autumn migration and exposed to the simulated geomagnetic field of northern Egypt increased food intake and attained...

2025, Ecological Engineering

e c o l o g i c a l e n g i n e e r i n g 3 2 ( 2 0 0 8 ) 320-328 a v a i l a b l e a t w w w . s c i e n c e d i r e c t . c o m j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / e c o l e n g

2025, Ecological Engineering

2025, Parasites & Vectors

Background: West Nile virus (WNV) is a widespread pathogen maintained in an enzootic cycle between mosquitoes and birds with occasional spill-over into dead-end hosts such as horses and humans. Migratory birds are believed to play an important role in its dissemination from and to the Palaearctic area, as well as its local dispersion between wintering sites. The Djoudj Park, located in Senegal, is a major wintering site for birds migrating from Europe during the study period (Sept. 2008-Jan. 2009). In this work, we studied the seasonal feeding behaviour dynamics of the potential WNV mosquito vectors at the border of the Djoudj Park, using a reference trapping method (CDC light CO 2 -baited traps) and two host-specific methods (horse-and pigeon-baited traps). Blood meals of engorged females were analysed to determine their origin. Results: Results indicated that Culex tritaeniorhynchus and Cx. neavei may play a key role in the WNV transmission dynamics, the latter being the best candidate bridging-vector species between mammals and birds. Moreover, the attractiveness of pigeon-and horse-baited traps for Cx. neavei and Cx. tritaeniorhynchus varied with time. Finally, Cx. tritaeniorhynchus was only active when the night temperature was above 20°C, whereas Cx. neavei was active throughout the observation period. Conclusions: Cx. neavei and Cx. tritaeniorhynchus are the main candidate vectors for the transmission of WNV in the area. The changes in host attractiveness might be related to variable densities of the migratory birds during the trapping period. We discuss the importance of these results on the risk of WNV transmission in horses and humans.

2025

Prefectural Izunuma-Uchinuma Foundation, and the Yamashina Institute of Ornithology to study whether migratory birds might carry the highly pathogenic H5N1 avian influenza virus from Asia to North America. We are using Northern Pintails (Anas acuta) as a model species to study intercontinental virus transmission because the species frequently migrates between Asia and North America, is abundant, and often carries avian influenza viruses. The various aspects of this project include: (1) an evaluation of spatial and temporal overlap of North American and Asian pintail populations through analysis of band recoveries, and marking of pintails with satellite transmitters on their Japanese wintering areas, (2) comparison of genetic differentiation of Asian and North American pintails to determine the degree to which populations are reproductively isolated, and (3) contrasting of strains of non-H5N1 viruses found in Northern Pintails on Japanese wintering areas and those on North American breeding and wintering areas to assess the recent and historic transcontinental transmission of avian viruses. Here we report on progress in these three areas of the study in 2007. We marked 27 pintails with satellite transmitters at one of their main wintering areas in Japan in February 2007. Fourteen pintails survived with operable transmitters to depart Japan for breeding areas in eastern Russia, and nine successfully completed migration to likely nesting and molting areas. Preliminary results suggest that after departing the northern Japanese island of Hokkaido, pintails either migrate to Sakhalin Island before going to the Russian mainland, or make a non-stop migration of >1600 km over the Sea of Okhotsk to the Kamchatka Peninsula or eastern Chukotka. Though results of the satellite telemetry are preliminary, there was considerable overlap between satellite telemetry locations of Japanese pintails on Russian nesting and molting areas, and areas that had a 95% likelihood of use by North American pintails, as delineated from band recovery data.

2025, River Research and Applications

On meandering rivers with well-developed floodplains, bankfull stage has geomorphological and ecological significance because it approximates the level of connection between the channel and the floodplain. As a river rises to bankfull stage, sediment begins to be deposited on the floodplain, wetlands are progressively inundated and organisms migrate between the channel and floodplain habitats. On many rivers large headwater dams have reduced the frequency and duration of floodplain inundation downstream. However, the lack of reliable pre-regulation flow data has made it difficult to quantify the effects of river regulation. This study used historical regulated and modelled natural flow data to determine the effects of regulation on the frequency and duration of bankfull flows on the Murrumbidgee River, one of Australia's largest and most heavily regulated rivers. In combination with floodplain surveys the flow data show that regulation has halved the frequency and duration of bankfull flows. This reduction in channel-floodplain connection has implications for the ecological health of the Murrumbidgee River.

2025, The Wilson Journal of Ornithology

inland from the Atlantic coast. The large hydroelectric lakes in the Southeast may provide a corridor for such inland invasion, especially if marsh island habitats are available. Such an inland expansion would resemble that which has occurred in the closely related Greattailed Grackle (Q. mexicanus), which has penetrated as far inland as Nebraska (Faanes and Norling, Amer. Birds 35:148-149, 198 1). I thank G. T. Bancroft and D. M. Forsythe for criticizing the manuscript. -WILLIAM POST, The Charleston Museum, 360 Meeting Street,

2025, Landscape Ecology

Context Urbanization has detrimental effects on biodiversity, yet how species respond to urban planning zoning outcomes and environmental changes at different spatial scales when selecting urban breeding habitats remains understudied.... more

2025, Wildfowl

Despite the recent decline in the Eastern Palearctic population of the Lesser Whitefronted Goose Anser erythropus (LWfG), numbers wintering in Japan have increased modestly since the 2000s. There have, however, been no systematic studies of the wintering ecology of the species previously conducted in Japan. In this study, count surveys were made of roosting and foraging sites, directed by tracking data from a GPS-tagged bird, to describe the movements of a wintering flock. The home range of the tagged LWfG during the 2020/21 winter was 9,120 ha (core area: 2,080 ha), and the distance between roosting and foraging sites ranged from 1.95-3.64 km. A change in the foraging and roost sites used by the geese was associated with low temperatures in mid-winter. This study provides preliminary information on the movements and habitat use by LWfGs in Japan, but further studies are required to improve our understanding of their wintering ecology, including their feeding habits and energy budgets, in relation to the quality and quantity of food resources available.

2025, Wildfowl

Of the world's Brent Goose Branta bernicla populations, the migration routes and winter distribution of the East Asian population of Brent Geese B. b. nigricans are the least well known. We therefore marked Brent Geese at their primary pre-migratory staging area in Notsuke Bay, Hokkaido, Japan to describe their migration between breeding and wintering areas in East Asia. Additionally, count data were compiled from the literature to identify important wintering and staging sites for the species, following Ramsar Convention criteria, and to assess trends in numbers of Brent Geese recorded in Japan and South Korea. The tracking data provided the first direct Migration and population status of Brent Geese in East Asia 245 © Wildfowl & Wetlands Trust Wildfowl (2020) Special Issue 6: 244-266 evidence of migratory connectivity between staging sites in northern Japan and the Korean Peninsula. A total of 26 internationally important sites were identified in the Russian Far East (7), northern Japan ( ), northeast China (2) and the Korean Peninsula (1). Autumn surveys made at staging sites in Japan indicate that the East Asian population is increasing, although more extensive surveys for Brent Geese in China and on the Korean Peninsula are needed to confirm overall population trends and to identify critical habitats and wintering sites. We encourage the continuation of tracking studies, to describe more precisely the main migration routes, staging areas and, importantly, the breeding grounds for this vulnerable Brent Geese population.

2025

Effective and efficient capture methods are needed for marking and monitoring individuals in studies of demography, migration and habitat use. We describe a novel use of leg-hold nooses aligned on lines and mats to capture non-breeding Brent Geese Branta bernicla in water at a staging and wintering site in Japan. A total of 24 Brent Geese were caught in autumn 2017 and 2018. The traps, which were easy to set up and transport, were effective at catching small numbers of Brent Goose at intertidal roosting and gritting sites. Leg-hold noose lines and mats may be a suitable alternative to other standard catching techniques, such as cannon-netting and flat net traps, in locations where it is not practicable to use these other methods.

2025

This special issue of Wildfowl has summarised our knowledge of the biogeographical populations of ten key Anatidae species in East Asia, their current and recent estimated abundance and distributions, their migration routes and movements, and sites of importance to these populations at key stages of their annual cycles. The analysis was possible only through the active cooperation of the many biologists and site managers involved in studies of these species in different countries participating in a collaborative programme of monitoring, research and analysis. Development of new telemetry and bio-logging technology has played a key role in our ability to describe linkages between the breeding, moulting, staging and wintering areas used by individual waterbirds. Compilation of movement data recorded for tracked individuals of each species has provided initial information on flyway delineation and range definition, which forms the basis for future identification of biogeographical popu...

2025, Journal of Applied Ecology

1. Populations of migratory birds often mix to a considerable extent in their wintering areas. Knowledge about the composition of wintering populations is highly relevant to management, not least for species such as the great cormorant Phalacrocorax carbo sinensis, prone to conflicts with human interests. However, few studies have been able to estimate long-term changes in winter population composition. 2. We use 30 years of ringing and recovery data from all major breeding populations of cormorants in continental Europe (except the Black Sea region) to estimate partitioning probabilities (i.e. the probabilities of moving to specific wintering areas) using a Bayesian capture-mark-recovery model. Combining these results with information on breeding numbers and reproductive output in a population model, we estimate the size and composition of wintering populations in Europe and North Africa. 3. Partitioning probabilities showed some variation over time, but were similar for first-winter and older birds. Cormorants from the western part of the breeding range tended to winter progressively further west over time. This may be a density-dependent response to the recent growth of more easterly breeding populations. 4. All wintering populations grew rapidly over the study period, and their composition showed pronounced changes. All wintering populations were composed of birds from many different breeding populations, but the proportion of cormorants of more easterly origin increased markedly over time in most wintering areas. of birds of different breeding origins. These mixtures are also highly variable over time. These factors reduce the chances of successfully limiting conflicts in specific wintering areas through, for example, regulation of breeding numbers in one breeding area. The dynamic nature of cormorant winter populations means that conflicts are best addressed when and where the conflict occurs, or on the scale of the entire continental population. It is unlikely that the latter will be cost-effective and politically realistic. How to cite this article: Frederiksen M, Korner-Nievergelt F, Marion L, Bregnballe T. Where do wintering cormorants come from? Long-term changes in the geographical origin of a migratory bird on a continental scale.

2025

After circa 35 years of drainage and intensive arable tillage, the lower Skjern River, Denmark was re-engineered to its original meanders and flooding regime, creating 22 km 2 of lakes, shallow wetlands and seasonally flooded grazed wet grassland costing €38 million. The primary motivation was to restore the sediment/nutrient retention capacity of the river valley to reduce eutrophication of Ringkøbing Fjord at its efflux. Secondary objectives were to (i) restore breeding and staging bird habitat, (ii) enhance the self-sustaining Atlantic Salmon Salmo salar population and (iii) improve recreational and tourist activities. Despite lack of specific success criteria, breeding waterbird numbers increased from 134 ± 22.9 SE (n = 3) pairs before to 1,744 ± 153 SE (n = 5) after restoration (although on average 1,004 of these were Black-headed Gulls Chroicocephalus ridibundus), species richness and diversity also increased. Twenty-nine waterbird species returned to breed, 10 of national or international significance (Danish Red List/European Union Birds Directive Annex 1 species) now ranking Skjern River amongst the top 10 most important breeding waterbird sites in Denmark. Currently, agriculture supports cost-neutral management of the restoration area, but whilst most expected wet meadow and marsh species had returned, lack of goal-orientated management targets resulted in some additional rare and threatened species remaining absent. Breeding pair density and diversity of other species could have been greatly improved by prior planning and management intervention but at additional cost.