Wintering Grounds Research Articles

Contaminants of emerging concern in an endangered population of common eiders (Somateria mollissima) in the Baltic Sea

Contaminants of emerging concern (CECs) are ubiquitous in aquatic environments and pose a range of biological effects including endocrine disruption. Yet, knowledge of their occurrence in wildlife including seabirds remains scarce. We investigated the occurrence of selected bisphenols, benzophenones, phthalate metabolites, benzotriazoles, benzothiazoles, parabens, triclosan, and triclocarban in plasma of 18 breeding female common eiders (Somateria mollissima) from an endangered population in the Baltic Sea as most of these CECs have never before been examined in eiders. We sampled blood at the start (T1) and end (T2) of incubation to investigate concentration changes during incubation. As early- and late-breeding eiders tend to differ in how they finance reproduction (local vs stored nutrient reserves), we compared early and late breeders to assess whether CEC concentrations differed by breeding phenology. Of the 58 targeted CECs, 21 were detected in at least one female, with bisphenol A (BPA) and benzophenone-3 (BzP-3) occurring most frequently (T1: 78% and 61%; T2: 61% and 67%, respectively), while mono(2-ethyl-1-hexyl) phthalate (mEHP), BPA, and monoethyl phthalate (mEP) were detected in the highest concentrations (median concentrations 27.1, 12.7, and 11.2 ng/g wet weight, respectively, at T1). No CEC concentrations differed between early and late incubation. Late breeders had significantly higher concentrations of BzP-3, monomethyl phthalate (mMP), and mEP during early incubation (4.55 vs 1.24 ng/g ww, 7.05 vs 3.52, and 11.2 vs < limit of detection (LOD), respectively) and significantly higher concentrations of mMP and mEP during late incubation (6.16 vs <LOD and 7.51 vs <LOD, respectively) than early breeders. We showed that early and late breeders exhibited differential exposure to CECs. Our results support the need for long-term monitoring of CECs in eiders. Furthermore, it is important to examine these CECs in the eiders’ prey species from their wintering and breeding grounds.

Blue and fin whale residence time and occupancy in Navy training and testing areas off the U.S. West Coast

Blue (Balaenoptera musculus) and fin (B. physalus) whales are prominent species in the California Current Ecosystem (CCE) using the area for migration and foraging. Blue whales migrate between tropical wintering grounds and higher latitude foraging grounds in the CCE, whereas fin whales may remain there year-round. We used Argos tracks of 182 blue (mean duration: 78 days) and 98 fin (mean duration: 35 days) whales tagged from 1994-2018 along the U.S. West Coast to examine residence time and occupancy in U.S. Navy training and testing areas. Bayesian hierarchical switching state-space model locations calculated from Argos tracks were used to provide residence time and proportion of tracking duration within each Navy area. We also calculated relative occupancy isopleths from the state space models, for both directed and non-directed movement, to assess spatial use of Navy areas. We then used generalized linear mixed models and beta regression to examine relationships between Navy area use and covariates, including six climate indices. Point Mugu Sea Range (PMSR) was the most heavily used Navy area by both species in terms of whale numbers, followed by the Southern California Range Complex (SOCAL). Residence time was longest in PMSR for blue whales and in the Northwest Training and Testing Study Area (NWTT) for fin whales. Blue whale use in PMSR was greater in summer versus autumn and for whales tagged in Southern versus Central California. Proportion of tracking duration decreased in all areas with increasing values of the Oceanic Niño Index (ONI), and in PMSR, with increasing values of the North Pacific Gyre Oscillation. Fin whale residence time was longer in PMSR during summer than winter or spring and decreased with increasing values of Habitat Compression Index and ONI. Proportion of tracking duration for fin whales was greatest in summer in PMSR and in winter in SOCAL and NWTT. Overlap of directed and non-directed movement was greatest in PMSR for both species. This assessment of blue and fin whale residence time and occupancy in Navy areas improves our understanding of potential threats these animals face, not only from military activities in Navy areas, but throughout the CCE.

Afro-Palaearctic migrant birds rid themselves of haemoparasite infections when breeding in the temperate zone

In migratory passerines, the prevalence and parasitaemia of blood parasites often increase towards the end of the breeding season. Consequently, post-breeding migration to winter quarters can be seen as a strategy to avoid the rising pathogen pressure during this time (migratory escape). I studied haemoparasite infections in sedge warblers (Acrocephalus schoenobaenus) inhabiting natural wetlands in southern Poland, examining the same individuals just after their arrival from wintering grounds, and again during incubation or nestling feeding. The birds were found to be infected more often immediately after arrival than during subsequent sampling. Parasitaemia also decreased significantly as the season progressed. The health status of individuals appeared to improve during the breeding season, whereas the higher level of parasitaemia just after arrival suggests that infections had occurred earlier, on the wintering grounds or during migratory stopovers.

Noninvasive Methods Unveil the Trophic Transmission of the Tapeworm Ligula intestinalis in Gull-Billed Terns.

Recent developments in microscopic and molecular tools have allowed the implementation of new approaches for assessing parasitic infections in wildlife populations. This is particularly important for the noninvasive detection and quantification of endoparasites in live animals. Here, we combined copromicroscopic (Mini-FLOTAC) and molecular (qPCR) techniques to detect the infection of the macroparasite Ligula intestinalis (Cestoda, Pseudophyllidea) in fresh droppings of Gull-billed Terns Gelochelidon nilotica (Charadriiformes, Laridae) breeding in southwestern Spain. Additionally, we sequenced the cytochrome b gene in parasite isolates from Gull-billed Terns (definitive host) and Common Bleak Alburnus alburnus (second intermediate host) sampled around tern colonies to explore potential genetic differences between the isolates. The qPCR test showed a higher prevalence (18%; in 13/73 samples) than Mini-FLOTAC (9%; in 8/88 samples), indicating that qPCR was more sensitive for diagnostic purposes than fecal flotation alone. Although the agreement between both techniques was substantial (84.2%) mainly due to the large number of uninfected samples, only Mini-FLOTAC allowed us to quantify parasite shedding. When combining techniques, the prevalence of infection did not differ between adults and chicks, suggesting frequent trophic transmission from parents to their offspring via food provisioning. Phylogenetic analyses identified four haplotypes in the isolates from Gull-billed Terns and Bleak, all of which were placed within a European clade composed of tapeworms recovered exclusively from phylogenetically derived cyprinid fish. This, combined with the short lifespan of mature tapeworms, suggests that Gull-billed Terns became infected after consuming infected fish around their breeding colonies rather than on their West African wintering grounds. Altogether, our results represent the first record of L. intestinalis in Gull-billed Terns and the first molecular characterization of the parasite in the Iberian Peninsula. This integrative coprodiagnostic protocol can be applied to other host-parasite systems, allowing researchers to study helminth infections in wild populations using a noninvasive approach.

The potential of roadside verges as insect habitat: Road salt has few effects on monarch butterfly performance and migration

AbstractRoadside habitat has been touted as a conservation opportunity for insect pollinators, including the declining monarch butterfly. The spectacular monarch migration is under threat from the loss of habitat and the decline of their milkweed host plants. In the northern part of their range, roadsides could potentially produce millions of monarchs annually due to high densities of milkweed; however, roadside milkweed can accumulate chemicals from roads, such as sodium from road salt. Controlled lab studies have shown mixed effects of sodium on monarch development: small increases can be beneficial as sodium is an important micronutrient in brain and muscle development, but large increases can sometimes decrease survival. It is unclear how dietary sodium affects performance in ecologically relevant conditions and the migration itself. In this experiment, we raised monarchs outdoors, in migration‐inducing conditions, on milkweed sprayed with three levels of sodium chloride. We released 2464 tagged monarchs and held an additional 246 for further lab assays. While our recovery rates to the wintering grounds were low (N = 7 individuals), individuals from all three sodium chloride treatments made it to Mexico. Butterflies reared on control milkweed and low salt concentrated sodium in their tissues, while those on high salt diets excreted sodium, suggesting high salt levels were above a physiological optimum. There were no effects of treatment on wing coloration, survival, body size, immunity, or parasite prevalence. Taken together, our results suggest that monarchs are robust to levels of sodium in milkweeds found along roadsides, which is promising with respect to the toxicity of roadside plants.

Timing mowing for maximal energy gain - Managing foraging habitat of wintering geese under extreme drought conditions

The availability of high-quality food resources is a critical determinant of wildlife fitness. Over the past two decades, phenological mismatch - the temporal misalignment between animals’ peak nutrient demand and optimal resource availability - has emerged as a significant conservation challenge. This issue is particularly worrisome for migratory birds, which must accumulate energy reserves to meet the elevated metabolic demands of migration between breeding and wintering grounds. In Poyang Lake, a crucial wintering ground along the East Asian-Australasian flyway, increasing asynchrony between vegetation growth and the migration of herbivorous waterbirds significantly impedes conservation efforts and presents a major management challenge for this Ramsar wetland. This study evaluates the efficacy of mowing, a grassland management measure, in regulating plant growth processes and restoring food resources for geese. In-situ mowing experiments were conducted with varying timings in Carex wet meadows, the primary foraging habitats of geese. Optimal mowing times were identified, and the maximum goose carrying capacity was assessed by comparing Carex growth and nutritional dynamics with goose dietary requirements. The results reveal that mowing effectively slows down the aging process of Carex, and protein content is identified as a critical limiting factor for geese foraging. Different mowing timings extend the suitable foraging period by 11–25 days. Estimates suggest varying carrying capacities with different mowing timings, supporting goose populations ranging from 133 to 2,046 in Changhuchi Lake during wintering. The optimal mowing window is early October, avoiding dates before late September and after late November. Moreover, multiple-stage mowing is recommended to accommodate different wintering stages. The study highlights mowing as a potential habitat restoration approach for goose conservation, effectively mitigating the challenges imposed by phenological mismatch directly and indirectly caused by anthropogenic activities.

Anas platyrhynchos (Mallard) has been replacing Anas rubripes (American Black Duck) in human-altered landscapes in Ontario, 1996 to 2019

Abstract Anas rubripes (American Black Duck) has received much attention over the years as a popular game bird species that experienced historical declines on its wintering grounds. Declines may be due to changes in the quality and quantity of breeding habitat, competition with A. platyrhynchos (Mallard), or both. Although the A. rubripes population has stabilized, spatial variation in regional population trends of A. rubripes on their breeding grounds can provide insight into the relative importance of these alternative hypotheses at provincial and local scales. We analyzed indicated breeding pairs count data collected in Ontario between 1996 and 2019 through the Eastern Waterfowl Survey to evaluate the correlation in breeding densities and trends of the 5 most abundant waterfowl species. We also tested whether habitat and anthropogenic disturbance variables could explain the distribution of those species. Overall, A. platyrhynchos breeding pair densities increased across the survey area, whereas A. rubripes breeding pair densities decreased in the southern and northern part of the survey area but remained stable in the central part. Densities of breeding pairs of A. rubripes and A. platyrhynchos were negatively correlated across survey plots but the trends in breeding densities were not correlated. Densities of A. platyrhynchos breeding pairs increased in human altered landscapes, whereas the density of A. rubripes breeding pairs was negatively correlated with agriculture. Our results suggest that A. platyrhynchos did not competitively exclude A. rubripes on the breeding grounds, but instead, A. rubripes were replaced by A. platyrhynchos following encroachment of agriculture into A. rubripes breeding habitat. Habitat management plans focused on breeding A. rubripes should emphasize reduction in the expansion of anthropogenic perturbations and increases in habitat conservation efforts in the central area of the breeding range in Ontario.

Occurrence of Novel and Legacy Per/Polyfluoroalkyl Substances (PFASs) in Scopoli’s Shearwater (Calonectris diomedea) Feathers

Per- and polyfluoroalkyl substances (PFASs) are contaminants of great concern due to their ubiquitous environmental occurrence in the environment and their potential adverse effects on organisms. There is currently limited information regarding the occurrence of PFASs in Scopoli’s Shearwater (Calonectris diomedea). In this study, two feather samples per bird were obtained from 26 adults on Strofades colony (Ionian Sea/Greece) during the early phase of the chick-rearing period (late July 2019). The samples consisted of barbs and barbules of the primary feathers, P1 and P10, reflecting pollution pressures at the time and the place of feather growth, i.e., at the species’ breeding and wintering grounds for P1 and P10, respectively. There were 25 PFAS detected in the feathers, with detection rates ranging from 2% (perfluorododecanoic acid—PFDoDA; perfluorohexane sulfonate—PFHxS; 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate—9Cl-PF3ONS; 2,3,3,3-tetrafluoro-2-(1,1,2,2,3,3,3-heptafluoropropoxy)propanoate—Gen-X) to 98% (sodium 1H,1H,2H,2H-perfluorooctane sulfonate; 6:2 FTSA). ∑PFAS ranged from 25.93 ng/g to 426.86 ng/g of feather sample. The highest mean concentration (109.10 ng/g feather) was reported for perfluorononanoic acid (PFNA). No significant differences in PFAS concentrations with high detection rate (&gt;20%) were found according to the sex of the birds. PFAS concentrations with a detection rate &gt; 20% in the P1 vs. P10 feathers of Scopoli’s Shearwater adults were not significantly different, reflecting the fact that breeding grounds in the Mediterranean and wintering grounds in the Atlantic seem to be contaminated with similar PFASs levels, even though some compounds showed regional trends.

Body condition of stranded Razorbills and Atlantic Puffins in the Western Mediterranean.

Annual mass migrations of seabirds between their breeding and wintering grounds are critical for ensuring their survival and reproductive success. It is essential to comprehend their physical condition in order to identify the causes of death and to facilitate conservation efforts. This study focuses on evaluating the age, body condition index, and metabolites in liver and muscle (triglycerides, glycerol, glycogen, cholesterol, lactate, and glucose) of stranded Razorbills (n = 84) and Atlantic puffins (n = 11). The study was conducted along the Andalusian coast of Spain during the winter season of 2022-2023. The study examined the body condition of stranded individuals and their metabolic state to determine potential factors that may have caused their deaths. The study found that the majority of stranded individuals were juveniles. Both species exhibited low levels of carbohydrate (glucose and glycogen) in their tissues and high levels of lactate in their muscles. These findings could suggest that the individuals had undergone prolonged, strenuous exercise, demanding energy on anaerobic pathways, which may have been associated with migration. The study highlights the significance of adhering to standardized protocols when assessing the body condition of stranded seabirds. Doing so can help to identify causes of death and facilitate conservation efforts. A proposed index for body condition, which incorporates biometric measurements and individual physical condition, provides a comprehensive means of understanding the health of these unique species. This study underscores the importance of further research into the conservation measures and recommendations for protecting seabird populations. It is critical to comprehend the contributing factors of mass mortality incidents to work towards safeguarding these species and preserving their vital migration patterns.

Seasonal migration patterns of Siberian Rubythroat (Calliope calliope) facing the Qinghai–Tibet Plateau

BackgroundSmall songbirds respond and adapt to various geographical barriers during their annual migration. Global flyways reveal the diverse migration strategies in response to different geographical barriers, among which are high-elevation plateaus. However, few studies have been focused on the largest and highest plateau in the world, the Qinghai–Tibet Plateau (QTP) which poses a significant barrier to migratory passerines. The present study explored the annual migration routes and strategies of a population of Siberian Rubythroats (Calliope calliope) that breed on the north-eastern edge of the QTP.MethodsOver the period from 2021 to 2023, we applied light-level geolocators (13 deployed, seven recollected), archival GPS tags (45 deployed, 17 recollected), and CAnMove multi-sensor loggers (with barometer, accelerometer, thermometer, and light sensor, 20 deployed, six recollected) to adult males from the breeding population of Siberian Rubythroat on the QTP. Here we describe the migratory routes and phenology extracted or inferred from the GPS and multi-sensor logger data, and used a combination of accelerometric and barometric data to describe the elevational migration pattern, flight altitude, and flight duration. All light-level geolocators failed to collect suitable data.ResultsBoth GPS locations and positions derived from pressure-based inference revealed that during autumn, the migration route detoured from the bee-line between breeding and wintering grounds, leading to a gradual elevational decrease. The spring route was more direct, with more flights over mountainous areas in western China. This different migration route during spring probably reflects a strategy for faster migration, which corresponds with more frequent long nocturnal migration flights and shorter stopovers during spring migration than in autumn. The average flight altitude (1856 ± 781 m above sea level) was correlated with ground elevation but did not differ between the seasons.ConclusionsOur finding indicates strong, season-dependent impact of the Qinghai–Tibet Plateau on shaping passerine migration strategies. We hereby call for more attention to the unexplored central-China flyway to extend our knowledge on the environment-migration interaction among small passerines.

Warming sea surface temperatures are linked to lower shorebird migratory fuel loads.

Warming sea surface temperatures (SSTs) are altering the biological structure of intertidal wetlands at a global scale, with potentially serious physiological and demographic consequences for migratory shorebird populations that depend on intertidal sites. The effects of mediating factors, such as age-related foraging skill, in shaping the consequences of warming SSTs on shorebird populations, however, remain largely unknown. Using morphological measurements of Dunlin fuelling for a >3000 km transoceanic migration, we assessed the influence of climatic conditions and age on individuals' migratory fuel loads and performance. We found that juveniles were often at risk of exhausting their fuel loads en route to primary wintering grounds, especially following high June SSTs in the previous year; the lagged nature of which suggests SSTs acted on juvenile loads by altering the availability of critical prey. Up to 45% fewer juveniles may have reached wintering grounds via a non-stop flight under recent high SSTs compared to the long-term trend. Adults, by contrast, were highly capable of reaching wintering grounds in non-stop flight across years. Our findings suggest that juveniles were disproportionately impacted by apparent SST-related declines in critical prey, and illustrate a general mechanism by which climate change may shape migratory shorebird populations worldwide.

Genetic diversity of the critically endangered Blue‐crowned laughingthrush (Garrulax courtoisi)

AbstractTo evaluate the genetic quality and provide available management strategies for Blue‐crowned laughingthrush (BCLT), fifteen polymorphic microsatellite loci were developed and applied. The genetic diversity of wild individuals was indicated to be higher than the two captive populations. The average number of alleles (5.50 ± 0.317), the number of effective alleles (3.417 ± 0.222), observed heterozygosity (0.828 ± 0.04), and genetic differentiation index (0.028 ± 0.007) of 64 wild individuals showed high genetic diversity despite drastic bottleneck and low genetic differentiation. The number of effective migrants (22.737 ± 8.318) indicated the intriguing wintering grounds may be surrounded by the breeding sites where the syncheimadia occurred in Wuyuan. Efficient conservation, winter flocking, and cooperative breeding may facilitate gene exchange and inclusive fitness. We recommend that monitoring concentrated distribution areas for BCLT should be strengthened, and geographical barriers, interference types, and the inner mechanism of distribution patterns should be further explored.

Southern breeding populations drive declining migration distances in Arctic and subarctic geese

Migration is a prevalent strategy among birds used to track seasonal resources throughout the year. Individual and population‐level migratory movements provide insight to life‐history variation, carry‐over effects, and impacts of climate change. Our understanding of how geographic variation in a species' breeding or wintering grounds can impact migration distances is limited. However, changes in migration distances can have important fitness consequences for individuals and conservation implications for populations, particularly if migratory connectivity is altered during the annual cycle. In this study, we use three decades of data from the United States Geological Survey Bird Banding Laboratory for six migratory species of Arctic and subarctic breeding geese. We employ a Bayesian hierarchical framework to test if the distance between breeding and wintering locations has changed over time, while accounting for the latitude of the breeding grounds. A model that included only a temporal trend estimated the average rate of change in migration distance, across all six species, at −3.0 km/year over the period 1990–2019. Five of the six species showed a significant decrease in migration distances. Including an interaction effect with breeding latitude revealed that the reduction in migration distance was strongest in the southernmost populations for four of the six species. For those species, migration distance in northern populations were all either relatively unchanged or increasing. This indicates that southern breeding populations of geese had a stronger association with the observed spatiotemporal changes in wintering ranges, potentially influenced by a combination of climatic and biotic factors (e.g. resource availability or competitive interactions) that uniquely impact these populations. Abundant, long‐term banding data shows promise for use in illuminating changes in migratory patterns under climate change, leading to improved management and conservation outcomes, from regional to continental scales.

Conserving low‐intensity farming is key to halting the declines of migratory passerines in their tropical wintering grounds

AbstractHalf of all migratory bird species have declined over the past 30 years, with intercontinental migrants declining faster than their short‐distance migratory counterparts. One potential cause of these declines is habitat loss and degradation on tropical wintering grounds, where agricultural conversion of natural habitats and intensification of traditional, low‐intensity agricultural systems are frequently occurring. Although the broad patterns of wintering migrant abundance are well understood along most flyways, how species' habitat associations vary across disturbance gradients in agricultural landscapes remains a key question, with implications for landscape‐level farm management and restoration activities. We used 328 point count locations and associated habitat assessments targeted at a cohort of eight severely declining Afro‐Palaearctic migratory passerines in the Guineo–Congolian transition zone of Western Africa to model the probability of the presence of migrants within grass, shrub, forb and forest‐covered areas. We found support for the widespread use of early successional habitats retained within traditionally managed farmland by migrants. Most species utilize scrubland on fallows within the agricultural mosaic, especially Spotted Flycatcher, Garden Warbler, Melodious Warbler, Whinchat and Common Nightingale. Only Pied Flycatcher relied upon mature forested areas. The avoidance of mature forested habitats by most species suggests that habitat requirements of severely declining migrant birds must be explicitly considered within conservation and restoration schemes, via mechanisms to retain low‐intensity farming, especially short‐term abandoned fallows that regenerate scrubby areas within the agricultural matrix. Any habitat management within the agricultural matrix should be considered in the context of the needs of local communities.

Year-round carryover effects are driven by migration phenology for Hirundo rustica (Barn Swallow) wintering in West Africa

Abstract Recently, population declines have been reported for many migratory birds. Because of complex life cycles, determining the causes for such declines is often difficult. Thus, migratory birds are of special conservation interest. We studied the migratory behavior of Hirundo rustica (Barn Swallow) tagged with solar geolocators and determined carryover effects during the entire annual cycle from one breeding season to the next. We used a partial least squares path model (PLS-PM) to disentangle migratory and breeding events that occur in chronological order. In addition, we controlled for broad environmental conditions in the wintering grounds (NDVI and latitude) and the specific molting habitat (δ13C). We did not find a carryover effect from reproduction investment in the attachment year to breeding success in the subsequent year. Individuals that invested more in reproduction departed earlier from the breeding colonies, but this in turn did not affect the onset of autumn migration. Thus, the premigratory period should be acting as a buffer stage counteracting any previous carryover effects from reproduction investment. On the other hand, we found a long-lasting domino effect from the onset of autumn migration to subsequent breeding success, consistent with the notion of a migratory race. Specifically, individuals which started earlier in the autumn migration arrived earlier to the wintering grounds, started earlier in the spring migration arrived earlier to the breeding colonies, and had a higher breeding success. We highlight that the premigratory period (i.e., the time elapsed between departure from breeding areas and the onset of autumn migration) should be important for the life cycle of migratory species, but it has been frequently overlooked.

Viral pathogen detection in U.S. game-farm mallard (Anas platyrhynchos) flags spillover risk to wild birds.

The threat posed by emerging infectious diseases is a major concern for global public health, animal health and food security, and the role of birds in transmission is increasingly under scrutiny. Each year, millions of mass-reared game-farm birds are released into the wild, presenting a unique and a poorly understood risk to wild and susceptible bird populations, and to human health. In particular, the shedding of enteric pathogens through excrement into bodies of water at shared migratory stop-over sites, and breeding and wintering grounds, could facilitate multi-species long-distance pathogen dispersal and infection of high numbers of naive endemic birds annually. The Mallard (Anas platyrhynchos) is the most abundant of all duck species, migratory across much of its range, and an important game species for pen-rearing and release. Major recent population declines along the US Atlantic coast has been attributed to game-farm and wild mallard interbreeding and the introduction maladaptive traits into wild populations. However, pathogen transmission and zoonosis among game-farms Mallard may also impact these populations, as well as wildlife and human health. Here, we screened 16 game-farm Mallard from Wisconsin, United States, for enteric viral pathogens using metatranscriptomic data. Four families of viral pathogens were identified - Picobirnaviridae (Genogroup I), Caliciviridae (Duck Nacovirus), Picornaviridae (Duck Aalivirus) and Sedoreoviridae (Duck Rotavirus G). To our knowledge, this is the first report of Aalivirus in the Americas, and the first report of Calicivirus outside domestic chicken and turkey flocks in the United States. Our findings highlight the risk of viral pathogen spillover from peri-domestically reared game birds to naive wild bird populations.

Are Current Protection Methods Ensuring the Safe Emancipation of Young Black Storks? Telemetry Study of Space Use by Black Storks (Ciconia nigra) in the Early Post-Breeding Period.

The black stork is a protected species in Poland, and its numbers have declined significantly in recent years. The protection of nesting sites during the period of growth and independence of young birds is crucial for the population. In 2022-2023, 34 young storks were equipped with GPS-GSM backpack loggers. On average, birds had left the nest by the 87th day of life. In the period between the first flight attempt and the final abandonment of the nest, the birds spent 82% of their time in a zone up to 200 m from the nest. During the period of independence, resting areas played an important spatial role, 75% of which were located within 500 m of the nest. As the young birds grew older, their area of activity gradually increased. Differences in nesting phenology were observed depending on the geographical location of the nest. A shorter migration route from the wintering grounds allowed for earlier breeding. As a result, the young birds begin to fledge earlier. The data collected confirm the validity of designating protective zones with 500 m radii around nests and the need to maintain them from the beginning of the breeding season in March until the end of August.

Multi-Scale Habitat Selection by the Wintering Whooper Swan (Cygnus cygnus) in Manas National Wetland Park, Northwestern China

Habitat selection has been a central focus of animal ecology, with research primarily concentrating on habitat choice, utilization, and evaluation. However, studies confined to a single scale often fail to reveal the habitat selection needs of animals fully and accurately. This paper investigates the wintering whooper swan (Cygnus cygnus) in Manas National Wetland Park, Xinjiang, using satellite tracking to determine their locations. The Maximum Entropy model (MaxEnt) was applied to explore the multi-scales habitat selection needs of Manas National Wetland Park’s wintering whooper swans across nighttime, daytime, and landscape scales. This study showed that the habitat selection of the wintering whooper swans varied in different scales. At the landscape scale, wintering whooper swans prefer habitats with average winter precipitations of 6.9 mm and average temperatures of −6 °C, including water bodies and wetlands, indicating that climate (precipitation and temperature) and land type (wetlands and water bodies) influence their winter habitat selection. During daytime, whooper swans prefer areas close to wetlands, water bodies, and bare land, with a more dispersed distribution of water bodies. For nighttime, they tend to choose areas within the wetland park where human disturbance is minimal and safety is higher. This study can provide scientific basis and data support for habitat conservation and management of wintering waterbirds like whooper swans, recommending targeted conservation measures to effectively manage and protect the wintering grounds of whooper swans.

Avian Influenza Virus and Avian Paramyxoviruses in Wild Waterfowl of the Western Coast of the Caspian Sea (2017-2020).

The flyways of many different wild waterfowl pass through the Caspian Sea region. The western coast of the middle Caspian Sea is an area with many wetlands, where wintering grounds with large concentrations of birds are located. It is known that wild waterfowl are a natural reservoir of the influenza A virus. In the mid-2000s, in the north of this region, the mass deaths of swans, gulls, and pelicans from high pathogenicity avian influenza virus (HPAIV) were noted. At present, there is still little known about the presence of avian influenza virus (AIVs) and different avian paramyxoviruses (APMVs) in the region's waterfowl bird populations. Here, we report the results of monitoring these viruses in the wild waterfowl of the western coast of the middle Caspian Sea from 2017 to 2020. Samples from 1438 individuals of 26 bird species of 7 orders were collected, from which 21 strains of AIV were isolated, amounting to a 1.46% isolation rate of the total number of samples analyzed (none of these birds exhibited external signs of disease). The following subtypes were determined and whole-genome nucleotide sequences of the isolated strains were obtained: H1N1 (n = 2), H3N8 (n = 8), H4N6 (n = 2), H7N3 (n = 2), H8N4 (n = 1), H10N5 (n = 1), and H12N5 (n = 1). No high pathogenicity influenza virus H5 subtype was detected. Phylogenetic analysis of AIV genomes did not reveal any specific pattern for viruses in the Caspian Sea region, showing that all segments belong to the Eurasian clades of classic avian-like influenza viruses. We also did not find the amino acid substitutions in the polymerase complex (PA, PB1, and PB2) that are critical for the increase in virulence or adaptation to mammals. In total, 23 hemagglutinating viruses not related to influenza A virus were also isolated, of which 15 belonged to avian paramyxoviruses. We were able to sequence 12 avian paramyxoviruses of three species, as follows: Newcastle disease virus (n = 4); Avian paramyxovirus 4 (n = 5); and Avian paramyxovirus 6 (n = 3). In the Russian Federation, the Newcastle disease virus of the VII.1.1 sub-genotype was first isolated from a wild bird (common pheasant) in the Caspian Sea region. The five avian paramyxovirus 4 isolates obtained belonged to the common clade in Genotype I, whereas phylogenetic analysis of three isolates of Avian paramyxovirus 6 showed that two isolates, isolated in 2017, belonged to Genotype I and that an isolate identified in 2020 belonged to Genotype II. The continued regular monitoring of AIVs and APMVs, the obtaining of data on the biological properties of isolated strains, and the accumulation of information on virus host species will allow for the adequate planning of epidemiological measures, suggest the most likely routes of spread of the virus, and assist in the prediction of the introduction of the viruses in the western coastal region of the middle Caspian Sea.

Composition and Conservation Status of Avifauna in Urban Non-protected Important Bird Area (IBA) Site of Western India

Kumbharwada wetland, an Important Bird Area (IBA) component in Bhavnagar, Gujarat, India, is a crucial wintering ground for migratory birds. Long-term monitoring of the avian community over a period of long time-frame is an excellent way to examine the health of this IBA site and thus provide an important ground to foster the conservation of birds in the region and management of this wetland. Given this consideration, field surveys were carried out from December 2020 to May 2023, following point count method to study the avian species richness in the study area. A total of 204 bird species belonging to 20 orders and 56 families are recorded, of which 85 species are migratory and 119 are resident. Anatidae is the most species-rich avian family (16 species). Highest number of species was recorded in the month of January (165 species in 2021 and 163 species in 2022). This wetland supports 107 (52.45%) wetland-associated species and 97 (47.55%) terrestrial species of birds. Twelve species are considered as Near Threatened, four species as Vulnerable and one species (Aquila nipalensis) as Endangered in IUCN Red List of Threatened Species. Four species (Sterna aurantia, Mycteria leucocephala, Phoeniconaias minor, and Threskiornis melanocephalus) with globally declining trend, are commonly seen in the study area, which shows that the wetland is a crucial habitat for bird species with high conservation priorities. Industrialization, encroachment, discharge of sewage water and chemical effluents, high-tension powerlines, stray dogs, and expansion of exotic vegetation remained the major threats to the habitat and avian community.