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Measures to boost populations can help ensure population persistence in the short‐term while longer‐term conservation interventions take effect. Headstarting, involving the collection of wild early life‐stage individuals, rearing in captivity, and release into a new or existing population once independent, has recently been identified as a potential translocation technique to assist small breeding populations of waders declining due to low levels of productivity. However, the demographic rates of headstarted individuals have not been quantified, and their impact on target populations not understood, which is required to determine the efficacy of this technique as a tool for species recovery. Between 2017 and 2022, headstarting was trialled as a tool to supplement the critically small sub‐population of black‐tailed godwit (Limosa limosa limosa) breeding at the Ouse Washes, Eastern England. We demonstrate that a high survival rate for eggs and chicks can be achieved through artificial incubation and hand‐rearing, and that headstarting can substantially increase the overall productivity of a small population. Using survival analysis and mixed effects modelling, we show that apparent survival and breeding success of headstarted individuals is comparable to wild‐reared conspecifics. The survival rate of released birds was sufficient to significantly boost the breeding population, reaching over five times the number of breeding pairs at the release site during the trial. Providing demographic rates remain the same, the number of godwits breeding at the Ouse Washes is predicted to continue to increase moderately over the next 20 years. This study highlights the potential of headstarting to boost small populations of breeding waders, and demonstrates the value of this technique to assist with the recovery of threatened populations when there is a clear justification that headstarting can negate the effects of population limiting factors. [ABSTRACT FROM AUTHOR]

Conventional life-history theory predicts that energy-demanding events such as reproduction and migration must be temporally segregated to avoid resource limitation. Here, we provide, to our knowledge, the first direct evidence of 'itinerant breeding' in a migratory bird, an incredibly rare breeding strategy (less than 0.1% of extant bird species) that involves the temporal overlap of migratory and reproductive periods of the annual cycle. Based on GPS-tracking of over 200 female American woodcock, most female woodcock (greater than 80%) nested more than once (some up to six times) with short re-nest intervals, and females moved northwards on average 800 km between first and second nests, and then smaller distances (ca 200+ km) between subsequent nesting attempts. Reliance on ephemeral habitat for breeding, ground-nesting and key aspects of life history that reduce both the costs of reproduction and migration probably explain the prevalence of this rare phenotype in woodcock and why itinerant breeding so rarely occurs in other bird species. [ABSTRACT FROM AUTHOR]

Artificial structures are often used as a tool for habitat restoration and the recreation of degraded coastal ecosystems and their associated food webs. However, it is often unknown if and how these artificial structures may influence the habitat use of target species, thereby hampering restoration goals. In this study, we test how artificial barriers, deployed to enhance the creation of an intertidal mussel bed, influenced the mussel‐habitat use by two bird species under pressure, Eurasian oystercatchers and Eurasian curlews. Average bird presence was monitored using time‐lapse camera's from the start of the mussel bed restoration in August 2018 until April 2019. We found that in the first few months of the experiment, both oystercatchers and curlews avoided the restored mussel beds containing artificial structures in the form of metal barriers that act as traps for dislodged mussels. Thereafter, the presence of barriers had no negative influence on the average presence of oystercatchers or curlews. In fact, curlews were significantly attracted to the mussel beds with barriers in January and February. In addition, we found a negative effect of the presence of European herring gulls on the presence of oystercatchers and curlews. The higher herring gull densities in the first 2 months of the experiment might explain the lower‐than‐expected curlew and oystercatcher densities observed in August. To our knowledge, no other studies have investigated the effect of artificial restoration structures on the abundance or habitat use of specific shorebirds. [ABSTRACT FROM AUTHOR]

Sexual behavior, including courtship and mating strategies, remains unexplored for numerous tropical birds. The Andean Lapwing (Vanellus resplendens) is a shorebird inhabiting the High Andes with a poorly known reproductive biology. Here, we aimed to describe behaviors of this species at the beginning of the breeding season. We performed 49 standardized observations of 20 pairs of Andean Lapwings at Laguna de Salinas, Arequipa, Peru, at 4,315 m asl, during the 2021–2022 breeding season. Lapwings in this studied population show (1) social monogamy and evident territoriality, (2) a defined breeding season apparently triggered by rainfall, and (3) a male-biased investment in courtship and territorial defense. Andean Lapwing pairs devoted 15% of their time to courtship activities, males on average doubled the amount of time of females—consisting mostly of nest scraping activities, various displays, and territory defense. Although these observations of Andean Lapwings increase our understanding of breeding strategies in populations inhabiting high-altitude landscapes, the reproductive behavior of most endemic species in the Neotropical mountains remains understudied and requires targeted investigations. El comportamiento sexual, incluyendo las estrategias de cortejo y apareamiento, siguen sin explorarse en numerosas especies de aves tropicales. Vanellus resplendens es un ave playera que habita los altos Andes, con una biología reproductiva poco conocida. En esta investigación, nuestro objetivo fue describir los comportamientos de esta especie durante el comienzo de la temporada reproductiva. Realizamos 49 observaciones estandarizadas de 20 parejas de Vanellus resplendens en la Laguna de Salinas, Arequipa, Perú a 4,315 m snm durante la temporada reproductiva 2021–2022. Las aves en esta población estudiada muestran: (1) monogamia social y territorialidad evidente; (2) una temporada reproductiva definida aparentemente por el inicio de las lluvias; y (3) una inversión en el cortejo y la defensa territorial sesgada hacia los machos. Las parejas de Vanellus resplendens dedicaron el 15% de su tiempo a actividades del cortejo, los machos en promedio duplicaron en tiempo a las hembras—que consisten principalmente en escarbar nidos y actividades relacionadas, despliegues terrestres y aéreos, y defensa de territorio. Aunque estas observaciones aumentan nuestra comprensión de las estrategias de reproducción en las poblaciones que habitan paisajes a gran altitud, el comportamiento reproductivo de la mayoría de las especies endémicas de las montañas neotropicales sigue siendo poco estudiado y requiere investigaciones específicas. Palabras clave: Andes, apareamiento, aves playeras, fenología, neotropical, reproducción. [ABSTRACT FROM AUTHOR]

There has been an increasing number of coastal restoration projects to eradicate Smooth cordgrass (Spartina alterniflora) and restore bare tidal flats to conserve waterbirds. However, the evidence for the assumed benefits to waterbirds and benthic organisms after such restoration efforts remains limited. We evaluated the impact of S. alterniflora eradication on waterbirds and benthic organisms in southern China. We deployed time‐lapse cameras and satellite trackers to quantify and compare the occurrence frequency and habitat use of birds in different habitats. We compared the density and biomass of benthic organisms collected in bare tidal flats and areas where S. alterniflora had been eradicated. We found that almost all waterbirds, except gulls, avoided areas where S. alterniflora was present. Once S. alterniflora was eradicated, the species richness and species‐level diversity of shorebirds and waterbirds did not differ significantly from those of the bare tidal flats. At least 9 out of 14 tracked individual shorebirds used areas where S. alterniflora had been eradicated, with Common Redshank (Tringa totanus) demonstrating a clear preference for such habitat. The density and biomass of benthos in deeper sediments (5–20 cm below the surface) were significantly lower in areas where S. alterniflora had been eradicated than in bare tidal flats, indicating that the food resources for birds may take longer than 1 year to recover. This research demonstrates that the eradication of S. alterniflora is important for the restoration of waterbird habitats, and such efforts should be made in areas that are important to waterbirds. [ABSTRACT FROM AUTHOR]

In biparental Charadriinae plovers, male and female incubation duties often resemble daily routines, with males typically incubating at night and females incubating during the day. By analysing incubation behaviour in three Arctic populations of Common Ringed Plover Charadrius hiaticula, we show that these diel routines are lost in the 24-h sunlight of the Arctic. In contrast, a non-Arctic population in East Scotland exhibited significant daily routines, with males dominating incubation during the late afternoon and night, and females dominating incubation during the early morning and midday hours. These patterns suggest that clear light/dark cycles are necessary for daily incubation routines to form in the Common Ringed Plover, although further research is needed to understand the specific drivers of this behaviour. [ABSTRACT FROM AUTHOR]

All animals host a microbial community within and on their reproductive organs, known as the reproductive microbiome. In free‐living birds, studies on the sexual transmission of bacteria have typically focused on a few pathogens instead of the bacterial community as a whole, despite a potential link to reproductive function. Theory predicts higher sexual transmission of the reproductive microbiome in females via the males' ejaculates and higher rates of transmission in promiscuous systems.We studied the cloacal microbiome of breeding individuals of a socially polyandrous, sex‐role‐reversed shorebird, the red phalarope (Phalaropus fulicarius). We expected (i) higher microbial diversity in females compared to males; (ii) low compositional differentiation between sexes; (iii) lower variation in composition between individuals (i.e. microbiome dispersion) in females than in males; (iv) convergence in composition as the breeding season progresses as a consequence of sexual transmission and/or shared habitat use; and (v) higher similarity in microbial composition between social pair members than between two random opposite‐sex individuals.We found no or small between‐sex differences in cloacal microbiome diversity/richness and composition. Dispersion of predicted functional pathways was lower in females than in males. As predicted, microbiome dispersion decreased with sampling date relative to clutch initiation of the social pair. Microbiome composition was significantly more similar among social pair members than among two random opposite‐sex individuals. Pair membership explained 21.5% of the variation in taxonomic composition and 10.1% of functional profiles, whereas temporal and sex effects explained only 0.6%–1.6%. Consistent with evidence of functional convergence of reproductive microbiomes within pairs, some select taxa and predicted functional pathways were less variable between social pair members than between random opposite‐sex individuals.As predicted if sexual transmission of the reproductive microbiome is high, sex differences in microbiome composition were weak in a socially polyandrous system with frequent copulations. Moreover, high within‐pair similarity in microbiome composition, particularly for a few taxa spanning the spectrum of the beneficial–pathogenic axis, demonstrates the link between mating behaviour and the reproductive microbiome. Our study is consistent with the hypothesis that sexual transmission plays an important role in driving reproductive microbiome ecology and evolution. [ABSTRACT FROM AUTHOR]

Integrating tracking technology and molecular approaches provides a comprehensive picture of contemporary and evolutionary mechanisms promoting connectivity. We used mitochondrial DNA and double digest restriction-site associated DNA (ddRAD) sequencing combined with satellite telemetry to investigate the connectivity of geographically disparate breeding populations of a declining boreal shorebird, the lesser yellowlegs (Tringa flavipes). We were able to track 33 individuals on their round-trip migrations to Central and South America and back to the boreal wetlands of North America. Nearly all (93%) adults captured on the breeding grounds returned to within 5 km of the original capture site, with a median dispersal distance of 629 m. While our telemetry data revealed limited breeding dispersal in adults, genetic data uncovered significant interconnectedness across the species' range. Very little genetic structure was estimated at ddRAD autosomal (ΦST = 0.001), Z-linked (ΦST = 0.001), and mtDNA loci (ΦST = 0.020), and maximum likelihood-based clustering methods placed all individuals in a single cluster regardless of capture location, indicating the species is panmictic. Our data indicate that large-scale juvenile dispersal is the main mechanism maintaining connectivity in this species, resulting in the absence of genomic structure. [ABSTRACT FROM AUTHOR]

Habitat use of indicator species is used to prioritize management activities. However, habitat use can vary temporally in response to changes in predation risk and foraging rewards. We deployed satellite tags on 20 black oystercatchers (Haematopus bachmani) in four regions of British Columbia, Canada, to examine habitat use and selection decisions across seasonal, diel and tidal cycles. We characterized the shoreline in each region and used GLMMs to investigate how habitat characteristics influenced shoreline use by tracked birds. For individuals, we estimated home range size and the frequency key features of the shoreline were re‐visited. Black oystercatchers generally made greater‐than‐expected use of rocky islets and shoreline with freshwater outflows, less tree cover and greater intertidal area. However, while black oystercatchers preferred islets and shoreline with less tree cover at most/all time periods, they only exhibited preferences for greater intertidal area during low tides, and preferences for shoreline with freshwater outflows during the nonbreeding season, day, and high tides. Individual home ranges, on average, contained 46 km of shoreline (range: 12–156 km) and individuals used 10.4 km (range: 6.7–13.9 km). Individuals made greater use of larger islets with less tree cover that were closer to outflows, and greater use of outflows associated with larger streams, greater intertidal areas and gravel substrates. Black oystercatchers' habitat preferences likely reduce predation risk (rocky islets and shoreline with less tree cover) and increase foraging rewards (shoreline with freshwater outflows, greater intertidal area, and gravel substrates). However, habitat preferences appear sensitive to constraints on movement in the breeding season and changes in foraging rewards across the diel and tidal cycle, highlighting the importance of examining habitat use at multiple temporal scales. Black oystercatchers are considered indicators of rocky intertidal health; therefore, critical habitat is expected to be important for a suite of wildlife dependent on safe and productive coastline. [ABSTRACT FROM AUTHOR]

Bahrain is a cluster of islands in the mid-section of the Arabian Gulf that serves as an important wintering and stop-over ground for many migratory shorebirds in the Central Asian Flyway (CAF). However, natural and anthropogenic factors have had a significant impact on these ecosystems over the last few decades. Long-term, systematic studies based on standardized survey observations are needed to understand the population dynamics and diversity changes of shorebirds in these critical sites. We systematically surveyed the shorebird population and community in Bahrain between 2010 January to 2021 December. This is the first comprehensive study from the entire Kingdom of Bahrain, and covered 13 sites over 12 years to establish the results. A total of 39 species were encountered during the study period from all 13 sites in Bahrain, of which 27 species were common and regular migrants to all the study sites; these were selected to analyze the population trend. Five species represented 77% or more of the total wintering shorebird population. All the shorebird species assessed exhibited significant declining trends over the years, and majority of them had over 1% relative abundance. Shorebirds in Bahrain were severely threatened at these sites, indicating that their population trend in the area could be crucially affected. Further conservation efforts are needed, aided by an understanding of the mechanisms driving the decline and diversity changes of shorebirds in the most stressed coastal regions of Bahrain. Further studies organized throughout the country's coasts may aid in establishing improved conservation measures to protect the shorebirds of the CAF in Bahrain. [ABSTRACT FROM AUTHOR]

The Prairie Pothole Region of central Canada supports a diverse community of breeding waterbirds, but many species have declining populations and the demographic mechanisms driving the declines remain unknown. We conducted a 7‐year field study during 1995–2001 to investigate the demographic performance of Marbled Godwits (Limosa fedoa) and Willets (Tringa semipalmata) breeding in managed wetlands near Brooks, Alberta. Mark‐recapture analyses based on Cormack–Jolly–Seber models revealed that the annual rates of apparent survival for Marbled Godwits (ϕ̂$$ \hat{\phi} $$ = 0.953 ± 0.012SE) and Willets (ϕ̂$$ \hat{\phi} $$ = 0.861 ± 0.015SE) are among the highest rates of survivorship reported for any breeding or nonbreeding population of large‐bodied shorebirds. Our estimates of life expectancy for males were comparable to longevity records in godwits (17.3 years ±5.8SE vs. 25–29+ years) and willets (7.7 ± 1.5SE vs. 10+ years). The two species both showed strong breeding site fidelity but differed in rates of mate fidelity. Pairs that reunited and males that switched mates usually nested <300 m from their previous nests, whereas females that switched mates usually moved longer distances >1.1–1.5 km. Returning pairs usually reunited in godwits (85%) but not in willets (28%), possibly because of species differences in adult survival or patterns of migration. Baseline estimates of annual survival for banded‐only birds will be useful for evaluating the potential effects of new tracking tags or the environmental changes that have occurred during the past 20 years. Conservation strategies for large‐bodied shorebirds should be focused on reduction of exposure to anthropogenic mortality because low rates of natural mortality suggest that losses to collisions at breeding sites or harvest at nonbreeding areas are likely to cause additive mortality. [ABSTRACT FROM AUTHOR]

Weather conditions experienced by birds can influence their migration decision‐making and strategy both within and across seasons. Additionally, decision‐making during migration may influence subsequent fitness (reproductive success and/or survival). Examining the effects of fine‐scale weather variables on individuals throughout the year could help identify stages of the annual cycle when species may be most affected by weather. In this study, we captured 24 black‐bellied plovers (gray plovers; Pluvialis squatarola) on nonbreeding areas along the western Gulf of Mexico coast and tracked their locations once every 2 h through their breeding season in the Alaskan and Canadian Arctic. We quantified migration strategies and weather conditions experienced by each individual throughout the nonbreeding, northward migration, and breeding seasons. We used a Bayesian hierarchical model which connected regressions linking weather with migration metrics, and migration metrics and breeding season weather with reproductive success. We found strong negative relationships between two migration metrics (migration duration and number of stopovers) and reproductive success, but no substantial relationships between breeding season weather variables and reproductive success. We found negative relationships between nonbreeding season temperature, migration temperature, and migration NDVI and both migration duration and number of stopovers, in addition to positive relationships between the number of stopovers and storms during migration, migration duration, and nonbreeding season precipitation. These results suggest that reproductive success is influenced by weather throughout the annual cycle and migration strategy is a key mechanism through which these effects operate. Our findings suggest that environmental factors throughout the year influence shorebird fitness, and, because black‐bellied plovers are often associated with mixed‐species flocks, many species likely experience similar constraints. [ABSTRACT FROM AUTHOR]

We investigate the relationship between weed invasion within naturally frequently disturbed areas on Broughton Island in New South Wales, Australia. One-hundred and five 5 × 5 m plots were placed across dunal areas of the island which are favoured locations for ground nesting birds. All vascular flora was recorded and scored for percent cover along with the number of burrows, percent of area covered by burrows, level of activity, if activity was recent and the percent of bare ground. Floristic analysis highlighted two divergent vegetation assemblages one dominated predominantly by mat-forming introduced taxa and one by natives. Areas of high weed dominance were associated with apparent low current Wedge-tailed Shearwater (WTS) activity and abandoned burrows. Conclusion: Our results indicate that low growing mat-forming introduced weeds may be promoted by frequent disturbance but also pose a threat to breeding by reducing the area that can be used by WTS. [ABSTRACT FROM AUTHOR]

Programs that incentivize private landowners to create habitats that offset losses due to conversion and climate change are increasingly being used to bolster sensitive wildlife populations. In the Central Valley of California, shorebird habitat incentive programs pay landowners to create additional habitat during the non‐breeding season by flooding their fields. However, it remains unclear how successful these programs have been in supporting baseline shorebird population needs or meeting established population goals, particularly in the face of changing environmental conditions. To address these questions, we used bioenergetics modeling to estimate shorebird food energy needs over four consecutive years that had the highest annual mean air temperatures ever recorded in California, and included years of extreme drought, as well as the second wettest winter on record. Our objectives were to (1) characterize annual variability in the timing and magnitude of shorebird food energy shortfalls, (2) estimate the contributions that incentive programs made to meeting these needs, and (3) develop recommendations for implementation of future habitat programs to advance shorebird conservation in the region. Overall, we found a high level of consistency in the timing and magnitude of habitat shortfalls, especially in fall, despite large differences in annual rainfall, a result that was unexpected, but that emphasizes how highly managed the hydrological system is in the Central Valley. We also found that the magnitude of both fall and spring energy shortfalls increased, relative to recent (2007–2014) estimates, perhaps due to aberrantly warm conditions. Incentive programs implemented to provide supplemental habitat were somewhat effective in reducing shortfalls for the assumed baseline population, but there were consistent unmet habitat needs when there were not enough shallow open water foraging areas available. Strategies to offset these remaining food energy deficits include scaling up habitat investments, adjusting the timing of habitat programs to better match the migration patterns of the birds, and adapting programs to new geographies. To the extent that there is variability in annual habitat need we recommend implementing a dynamic conservation approach. This involves scaling the amount of additional habitat created to match the shifting needs of the birds to maximize return on investment. [ABSTRACT FROM AUTHOR]

The use of unique markers in ornithology has a long history and is predicated on the assumption that markers have negligible effects on behavior and survival. The assumption that marks are harmless is particularly important with imperiled species. We studied the effects of two different marking schemes on Piping Plovers (Charadrius melodus), a small shorebird protected under the U.S. Endangered Species Act that is intensively monitored and managed. We used two marking schemes, (1) color bands and (2) uniquely engraved flags during breeding seasons from 2013 to 2023 to determine whether the injuries were causing additive mortality and thus actually limiting populations. We estimated the effect of perceived limping and injury (e.g., swelling, laceration, etc.) on chick and hatch-year survival. We detected injuries in some years and associated with both marking schemes (range 0.0–6.0%, average = 2.7% of marked chicks each year). Interval survival for banded chicks was like that of flagged chicks (β\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\beta $$\end{document} = − 0.55, 95% BCI: − 1.30–0.33, f = 0.92). Mean survival to fledging, however, was higher in years where flags were used (ϕ¯=\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\overline{\phi }=$$\end{document} 0.55 ± 0.14) than when bands were used (ϕ¯=\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\overline{\phi }=$$\end{document} 0.34 ± 0.14), but we surmise that this difference was partly conflated with negative density-dependent factors (β\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\beta $$\end{document} = − 0.49, 95% BCI: − 0.73 to − 0.25, f = 1.00) and predation. Our results show that pre-fledge survival of birds with uniquely coded flags was similar to that of birds receiving color bands. There was also no evidence that injured birds had a significantly lower hatch-year survival than those that were not injured. However, the relatively high (up to 6%) injury rate in some years remains a concern. Injury and survival rates need to be considered and evaluated when deciding on whether to mark individuals. Ultimately, wildlife practitioners should strive to use the best methods for information gathering and management, without negatively impacting the species. [ABSTRACT FROM AUTHOR]

Migration patterns in birds vary in space and time. Spatial patterns include chain, leapfrog and telescopic migration. Temporal patterns such as migration duration, number, and duration of stopovers may vary according to breeding latitude, sex, and season. This study aimed to verify these patterns in a long‐distance migrant, the Eurasian curlew Numenius arquata arquata, and to provide a synopsis of spatio‐temporal migration patterns in this species of concern throughout the East Atlantic Flyway. We tagged 85 adults with GPS‐data loggers in Germany, Poland, France and Estonia between 2013 and 2019. We computed the distance flown, linear loxodromic distance, duration, stopover number, total stopover duration, mean stopover duration, departure time and arrival time for 177 out of 187 tracks. On average (± standard deviation), spring migration occurred from 4 to 14 April (10.2 ± 8.4 days), curlews flew 3.623 ± 1.366 km, and had 5.8 ± 3.6 stopovers, with a duration of 29.4 ± 38.2 h per stopover, while autumn migration occurred from 18 to 29 June (10.9 ± 9.9 days), curlews flew 3.362 ± 1.351 km, and had 5.4 ± 4.0 stopovers, with 31.8 ± 32.3 h per stopover. Curlews displayed chain migration because wintering curlews maintained the latitudinal sequence to their breeding sites. Southern curlews had a longer nesting period due to their earlier arrivals. While spring arrival at breeding sites did not differ between the sexes, in autumn females departed earlier than males. Migration duration and distance, as well as stopover number and duration, showed a significant increase with breeding site latitude but did not differ between the sexes or between spring and autumn migrations, suggesting that curlews took a comparable amount of time migrating during both seasons. The high site faithfulness in curlews suggests that rapid autumn migration allows them to return to defend their winter foraging areas. [ABSTRACT FROM AUTHOR]

Satellite and GPS tracking technology continues to reveal new migration patterns of birds which enables comparative studies of migration strategies and distributional information useful in conservation. Bar‐tailed godwits in the East Asian–Australasian Flyway Limosa lapponica baueri and L. l. menzbieri are known for their long non‐stop flights, however these populations are in steep decline. A third subspecies in this flyway, L. l. anadyrensis, breeds in the Anadyr River basin, Chukotka, Russia, and is morphologically distinct from menzbieri and baueri based on comparison of museum specimens collected from breeding areas. However, the non‐breeding distribution, migration route and population size of anadyrensis are entirely unknown. Among 24 female bar‐tailed godwits tracked in 2015–2018 from northwest Australia, the main non‐breeding area for menzbieri, two birds migrated further east than the rest to breed in the Anadyr River basin, i.e. they belonged to the anadyrensis subspecies. During pre‐breeding migration, all birds staged in the Yellow Sea and then flew to the breeding grounds in the eastern Russian Arctic. After breeding, these two birds migrated southwestward to stage in Russia on the Kamchatka Peninsula and on Sakhalin Island en route to the Yellow Sea. This contrasts with the other 22 tracked godwits that followed the previously described route of menzbieri, i.e. they all migrated northwards to stage in the New Siberian Islands before turning south towards the Yellow Sea, and onwards to northwest Australia. Since the Kamchatka Peninsula was not used by any of the tracked menzbieri birds, the 4500 godwits counted in the Khairusova–Belogolovaya estuary in western Kamchatka may well be anadyrensis. Comparing migration patterns across the three bar‐tailed godwits subspecies, the migration strategy of anadyrensis lies between that of menzbieri and baueri. Future investigations combining migration tracks with genomic data could reveal how differences in migration routines are evolved and maintained. [ABSTRACT FROM AUTHOR]

Environmental research often occurs in short bursts with the duration of fieldwork often governed by the time constraints of a funding body. Collaborations between academic researchers and Indigenous People have occurred for many years and the exchange of information can create value and knowledge for both participants in the collaboration. Indigenous People play a vital role as knowledge keepers in environmental science and can, in some instances, provide a more secure repository of local knowledge and conservation practice than digital archives. In this essay, Indigenous Rangers on Larrakia country in Darwin, Australia, and a non‐Indigenous academic researcher describe how value‐creation was increased for both parties involved in a collaborative project on the migratory shorebird far eastern curlew (Numenius madagascariensis). We share our experiences of expectations, the development of methods, the codeveloped goals and complementary ways of thinking to manage threatened species at a local scale, the scale at which the local Larrakia People operate. Through our collaboration, we show that both parties within the collaboration can benefit and create value for a species of conservation concern that has not typically been considered culturally important. [ABSTRACT FROM AUTHOR]

Collecting empirical data is essential for understanding the ecology and biology of a species. If the data collection procedure includes direct interaction with the study subject, particularly regarding repeated measures, there may be a risk of introducing biases on the collected dataset due to changes in the behaviour and/or physiology of the studied individuals. This can be particularly relevant during the breeding season when disturbance by researchers can affect birds on various aspects, including nest and chick survival, physiology, and chick body condition. Researcher effects on the chicks’ body condition have been shown in some species, but were apparently absent in others. Here, we investigate whether varying levels of handling influences the body condition of Eurasian whimbrel (Numenius phaeopus) chicks, using data collected on 88 individuals handled up to 11 times, during two breeding seasons. We found that neither the handling event (ordinal occasion when a chick was handled) nor the handling interval (period between two consecutive handling events) affected the chick’s body condition, but we found evidence that body condition is individually consistent during development. Hence, the levels of handling in our study did not have an apparent effect on Eurasian whimbrel chicks’ body condition. Although other potential effects may arise via researchers’ disturbance, our findings contribute to the discussion on researchers’ impacts on their study subjects, emphasizing the importance of species-specific evaluations to improve research methodologies and ethical practices. [ABSTRACT FROM AUTHOR]

Sexing bird species with monomorphic plumage is generally challenging, and sexual size dimorphism (SSD) is often used to develop morphometric-based sexing tools, e.g., using discriminant functions. Within species, local selection pressures, age-related and season-related growth may, however, induce geographical and temporal variations in body size and SSD. Such variations may complicate the development of reliable morphometric-based sexing methods at a broad scale. We first investigated body size variations in a migratory shorebird species with wide breeding and wintering ranges, the Sanderling Calidris alba, within the two breeding populations (Greenland and Russia) and three staging/wintering populations (United Kingdom, Iceland and Mauritania), which belong to the same flyway. Then, for samples from each region, we tested whether site-specific (i.e., “regional”) functions performed better than functions developed for birds from the other sites (i.e., “foreign” functions) or than an overall (“flyway”) function that combined all sampled individuals. We found minor variations in SSD between regions, but significant differences in body size between sexes and regions. Females were larger than males and, for instance, breeders had longer wings than staging and wintering birds. Regional functions had similar sexing efficiency as any other functions applied to sample from each region, except for Western Africa where the regional function performed slightly better than some of the other functions. Furthermore, the flyway function developed after merging all subsamples had a similar efficiency than the regional functions, i.e., from 75.4% to 90% of correct sex assignment depending on the region. Given the small or lack of benefit in using regional functions, we conclude that the flyway function can be used reliably to sex Sanderlings measured at different sites, years or seasons within the East Atlantic flyway. Our results may help to develop global sexing function for other bird species. [ABSTRACT FROM AUTHOR]

A 2-year surveillance study of influenza A viruses in migratory birds was conducted to understand the subsequent risk during the migratory seasons in Dandong Yalu River Estuary Coastal Wetland National Nature Reserve, Liaoning Province, China, a major stopover site on the East Asian-Australasian flyway. Overall, we isolated 27 influenza A viruses with multiple subtypes, including H3N8 (n = 2), H4N6 (n = 2), H4N7 (n = 2), H7N4 (n = 9), H7N7 (n = 1), H10N7 (n = 7), and H13N6 (n = 4). Particularly, a novel reassortant influenza A(H7N4) virus was first identified in a woman and her backyard poultry flock in Jiangsu Province, China, posing a serious threat to public health. Here, we describe the genetic characterization and pathogenicity of the nine influenza A(H7N4) isolates. Phylogenetic analysis indicated that complex viral gene flow occurred among Asian countries. We also demonstrated a similar evolutionary trajectory of the surface genes of the A(H7N4) isolates and Jiangsu human-related A(H7N4) viruses. Our A(H7N4) isolates exhibited differing degrees of virulence in mice, suggesting a potential risk to other mammalian species, including humans. We revealed multiple mutations that might affect viral virulence in mice. Our report highlights the importance and need for the long-term surveillance of avian influenza virus in migratory birds combined with domestic poultry surveillance along migratory routes and flyways and, thereby, the development of measures to manage potential health threats. [ABSTRACT FROM AUTHOR]

Species of conservation concern often receive intensive management to improve vital rates and facilitate recovery. Piping plovers (Charadrius melodus) are federally listed in the United States and concerns over nest depredation have prompted widespread use of plover‐permeable predator exclosures placed around nests (0.5–2‐m radius). While effectiveness of exclosures for improving nest survival has been demonstrated, concerns remain about decreased chick survival (through predator cueing or density‐dependent processes) or increased vulnerability of adults to predation (ambush as adult leaves exclosure). Either one of these concerns could demographically outweigh the benefits of increased nest survival. During 2014–2016, we conducted an experiment designed to evaluate survival of uniquely identified nests (n = 418), chicks (n = 453), and adults (n = 367) at wetlands across the Northern Great Plains, USA. We assigned wetlands (n2014 = 26, n2015 = 28, n2016 = 25) into 2 groups: wetlands in which half of the nests received exclosures and wetlands in which none of the nests received exclosures. Exclosed nests had greater cumulative survival (0.73 [85% CI = 0.70–0.77]) than unexclosed nests at treatment wetlands (0.58 [0.54–0.62]) or unexclosed nests at control wetlands (0.52 [0.49–0.56]). Survival to fledging was highest for chicks hatched from exclosed nests (0.51 [0.47–0.56]), and similar between chicks hatched from unexclosed nests at treatment (0.34 [0.30–0.39]) and control (0.37 [0.32–0.42]) wetlands. Cumulative survival of adults during incubation varied by exclosure status, but adults associated with exclosed nests (0.90 [0.88–0.93]) and unexclosed nests at treatment wetlands (0.89 [0.86–0.92]) had greater survival than those associated with unexclosed nests at control wetlands (0.75 [0.64–0.84]). Adult annual survival rates varied by year (0.79–0.95) but not by exclosure status. The positive influence of exclosures on nest survival was not offset by a reduction in chick or adult survival, indicating that exclosures are a viable tool for piping plover conservation. [ABSTRACT FROM AUTHOR]

Adult survival is a key component of population dynamics, and understanding variation in and the drivers of adult survival rates and longevity is critical for ecological and evolutionary studies, as well as for conservation biology and practice. Tropical species of landbirds are often selected to have higher adult survival due to high nest predation rates, but it is unclear if the same patterns occur in other avian lineages with different life history strategies. Here, we investigate adult survival of three sympatrically breeding species of shorebirds in south‐west Madagascar: the endemic and endangered Madagascar plover Charadrius thoracicus and two more widely distributed African species: the white‐fronted plover C. marginatus and the Kittlitz's plover C. pecuarius. Using mark–recapture data from 1843 individuals breeding at an intensely monitored saltmarsh over a 13‐year period, we estimated annual rates of apparent survival (φ) corrected for encounter probability. Adult apparent survival rates were high for all three species (mean ± SE): Madagascar (φ = 0.899 ± 0.010) and white‐fronted plovers (φ = 0.923 ± 0.008). Kittlitz's plovers showed a difference between the first (φ1 = 0.719 ± 0.026) and subsequent transitions (φ2+ = 0.892 ± 0.014), suggesting that transient breeders are common in this species. For birds first captured as adults, these survival estimates translate to life expectancies of 9.72 (±1.11) years in Kittlitz's plovers, 9.36 (±0.98) years in Madagascar plovers and 12.48 (±1.32) in white‐fronted plovers. We hypothesise that a long lifespan could be an adaptation arising from the unique climatic pressures on the island of Madagascar that would otherwise lead to reduced fitness. However, long lifespans may not sufficiently compensate for a reduction in breeding opportunities due to possible climatic disruption in the future. Consequently, at least two of these plover species seem vulnerable to ongoing habitat destruction and changing climate cycles. [ABSTRACT FROM AUTHOR]

Breeding habitat loss and nest predation are considered the main causes of Snowy Plover (Charadrius nivosus) populations decline worldwide. We evaluated the effects of season, nest age, distance to nearest vegetation patch, distance to nearest body of water, habitat type, and nesting substrate on the daily survival rate of Snowy Plover nests. During 2014-2015, we located 84 nests in Las Garzas-Chahuin-Chihua lagoon in Marismas Nacionales, Nayarit, Mexico. We used MARK software to estimate daily nest survival rate, which was 0.969 (95% CI = 0.95 - 0.97) for both breeding seasons combined, with a 42% finite nesting success. A total of 44 nests (52%) were successful, while 40 (48%) failed. The main causes of nest failure were predation (n = 30; 75% of failed nests) and flooding (n = 9; 22.5% of failed nests); one nest was lost due to unknown causes (2.5%). Daily survival rate increased with nest age and distance from the nearest vegetation patch. By contrast, daily survival rate decreased with the progression of the breeding season; a higher probability of nest success was evident when established early in the breeding season. Our results show the importance of different positive and negative factors influencing nest survival that might be considered as part of conservation strategies. [ABSTRACT FROM AUTHOR]

Semipalmated sandpiper (Calidris pusilla) migration to the Southern Hemisphere includes a 5‐day non‐stop flight over the Atlantic Ocean, whereas semipalmated plover (Charadrius semipalmatus) migration, to the same area, is largely over land, with stopovers for feeding and rest. We compared the number and 3D morphology of hippocampal astrocytes of Ch. semipalmatus before and after autumnal migration with those of C. pusilla to test the hypothesis that the contrasting migratory flights of these species could differentially shape hippocampal astrocyte number and morphology. We captured individuals from both species in the Bay of Fundy (Canada) and in the coastal region of Bragança (Brazil) and processed their brains for selective GFAP immunolabeling of astrocytes. Hierarchical cluster analysis of astrocyte morphological features distinguished two families of morphological phenotypes, named type I and type II, which were differentially affected after migratory flights. Stereological counts of hippocampal astrocytes demonstrated that the number of astrocytes decreased significantly in C. pusilla, but did not change in Ch. semipalmatus. In addition, C. pusilla and Ch. semipalmatus hippocampal astrocyte morphological features were differentially affected after autumnal migration. We evaluated whether astrocyte morphometric variables were influenced by phylogenetic differences between C. pusilla and Ch. semipalmatus, using phylogenetically independent contrast approach, and phylogenetic trees generated by nuclear and mitochondrial markers. Our findings suggest that phylogenetic differences do not explain the results and that contrasting long‐distance migratory flights shape plasticity of type I and type II astrocytes in different ways, which may imply distinct physiological roles for these cells. [ABSTRACT FROM AUTHOR]

Although invasive non‐native species can adversely affect biodiversity in many ways, predation of native species by non‐native species on islands can be severely damaging. Results of numerous studies document non‐native birds preying on birds on islands, but our understanding of the number and type of species affected has been limited by the lack of a global review of these impacts. I identified the non‐native bird species that have been recorded preying on birds, the locations where this predation occurred, and the bird species affected. Because the impacts of non‐native birds can be particularly severe on small islands, I then identified the islands <500 km2 around the world that are occupied by predatory non‐native birds. By taking into account their life‐history traits and predation history, I also identified the near‐threatened and threatened bird species on these islands that they may prey on. The results indicated that predation by non‐native birds was primarily a concern for threatened bird conservation on small islands; almost all predation impacts (91%) on near‐threatened and threatened birds were recorded on islands, and median island size was 106 km2. I also found non‐native bird predation was a poorly known and widespread potential threat to avian biodiversity; worldwide, 194 islands of <500 km2 were occupied by predatory non‐native birds, but information on their impacts was unavailable for most of these islands. On them, where the impacts of non‐native species can be severe, non‐native birds may be preying on approximately 6% of the world's near‐threatened and threatened bird species. Four non‐native bird species I identified have been successfully eradicated from islands. If they were eradicated from the small islands they occupy, 70% of the near‐threatened and threatened bird species I identified would no longer be affected by nest predation by non‐native birds on small islands. Article impact statement: On small islands, non‐native birds may be preying on approximately 6% of the world's near‐threatened and threatened bird species. [ABSTRACT FROM AUTHOR]

Background: Despite an increasing number of surveys and a growing interest in birdwatching, the population and distribution of Asian Dowitcher (Limnodromus semipalmatus), a species endemic to the East Asian–Australasian and Central Asian Flyways, remains poorly understood, and published information about the species is largely outdated. In boreal spring 2019, over 22,432 Asian Dowitchers were recorded in a coastal wetland at Lianyungang, Jiangsu Province, China, constituting 97.5% of its estimated global population. Methods: In 2019 and 2020, we conducted field surveys at Lianyungang to determine the numbers of Asian Dowitchers using the area during both southward and northward migrations. We also assessed the distribution and abundance of Asian Dowitchers elsewhere along the China coast by searching literature and consulting expert opinion. Results: The coastal wetlands of Lianyungang are the most important stopover site for Asian Dowitchers during both northward and southward migrations; they supported over 90% of the estimated global population during northward migration in two consecutive years (May 2019 and 2020). This area also supported at least 15.83% and 28.42% (or 30.74% and 53.51% using modelled estimates) of the global population during southward migration in 2019 and 2020 respectively. Coastal wetlands in the west and north of Bohai Bay also have been important stopover sites for the species since the 1990s. Although comprehensive, long-term monitoring data are lacking, available evidence suggests that the population of the species may have declined. Conclusions: The high concentration of Asian Dowitchers at Lianyungang during migration means the species is highly susceptible to human disturbances and natural stochastic events. The coastal wetlands of Lianyungang should be protected and potentially qualify for inclusion in China's forthcoming nomination for World Heritage listing of Migratory Bird Sanctuaries along the Coast of Yellow Sea-Bohai Gulf of China (Phase II) in 2023. Additional research is needed to understand Asian Dowitchers' distribution and ecology, as well as why such a high proportion of their population rely on the Lianyungang coast. [ABSTRACT FROM AUTHOR]

Many shorebirds rely on small numbers of staging sites during long annual migrations. Numerous shorebird species are declining and understanding the importance of these staging sites is important for successful conservation. We surveyed endangered rufa red knots (Calidris canutus rufa) staging in James Bay, Ontario, Canada, during southbound migration in 2017 and 2018. We used mark‐resight data and count data in an integrated Bayesian analysis to quantify migration phenology, estimate passage population size, and model the age structure of the stopover population. Many adult red knots arrived in James Bay in a single wave in early August in 2017, whereas adult red knots arrived in multiple smaller waves in July and mid‐August in 2018. These waves may correspond with breeding phenology where more red knots bred successfully and arrived in one large event in 2017 and the higher number of earlier arrivals in July 2018 may have been failed breeders. We included a binomial generalized linear model in the integrated analysis to estimate that 20% and 10% of staging red knots were juveniles in 2017 and 2018, respectively. In future applications, this method could provide a metric to assess breeding performance and develop our understanding of its role in population declines. Overall, we estimated that up to 23% of the estimated rufa red knot population staged in southwestern James Bay for an average of 10–12 days. The region is a key staging site for endangered red knots and could be included in conservation planning. © 2021 The Wildlife Society. : We used an integrated Bayesian analysis to estimate passage population size and migration phenology of endangered red knots staging in southwestern James Bay, Ontario, Canada during southbound migration. Our integrated analysis included a method to model the age structure of the population, which could be used as a tool to monitor breeding success. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) impaired pre‐migratory fueling in 49 orally dosed Sanderling (Calidris alba). In the present study, 8 genes related to fat deposition and PAH exposure were measured in liver subsamples from these same shorebirds. At the highest dose (1260 µg total PAH [tPAH]/kg body wt/day), PAH exposure decreased liver basic fatty acid binding protein 1 (Lbfabp) and hepatic lipase (Lipc) expression. The present study reveals candidate molecular‐level pathways for observed avian pre‐migratory refueling impairment. Environ Toxicol Chem 2021;40:1983–1991. © 2021 SETAC [ABSTRACT FROM AUTHOR]

Factors affecting stopover duration in birds are still much discussed. Field studies report contradictory evidence regarding the effect of fuel reserves on bird decision to depart from a stopover site, while the majority of laboratory tests performed on passerines reported a positive relationship between body conditions and migratory restlessness. In recent years, a few studies integrating laboratory and field investigations suggested that the amount of migratory restlessness could be a proxy of the individual willingness to depart from a stopover site in night-migrating passerines, but similar studies are lacking for other groups of birds. In this paper the factors affecting stopover length in the Wood sandpiper Tringa glareola (Charadriiformes Scolopacidae) were studied by integrating field observations and laboratory tests during spring migration. Our aims were to investigate (1) the influence of body conditions on migratory restlessness and (2) the influence of body conditions and of the amount of migratory restlessness on stopover duration, after controlling for meteorological conditions. Contrary to our expectations, we did not find any relationship between body condition and migratory restlessness nor stopover duration, while for the 1st time in a non-passerine species, evidence was produced that the amount of migratory restlessness is significantly related to the likelihood of leaving the stopover area. Our results emphasize the relevance of the studies integrating field and laboratory tests to understand the physiological and ecological factors affecting migratory behaviour in different bird species. Body conditions seem to be unrelated both to migratory restlessness and stopover duration. Migratory restlessness predicts the likelihood of leaving the stopover site. The quantification of migratory restlessness seems to be a useful tool for studying the effect of intrinsic and extrinsic factors on stopover behaviour in shorebirds. [ABSTRACT FROM AUTHOR]

The article explores the Least Tern (Sternula antillarum) commonly breeds along coastal beaches and major interior rivers of North America and the Caribbean. Least Terns have been observed in Hawai‘i since the 1970s; however, few breeding attempts have been documented. Nests have been discovered on the northwestern Hawaiian island of Midway Atoll and the southeastern Hawaiian island of Hawai‘i.

In this paper, we extend our understanding of the migration of Black-tailed Godwits (Limosa limosa limosa) by describing: (1) the orientation and geographic locations of individual migratory routes and (2) the spatial distribution of godwits across seasons and years. We accomplish this using satellite-tracking data from 36 adult godwits breeding in the 200-ha Haanmeer polder in The Netherlands, from 2015 to 2018. During both southward and northward migration, godwits used a narrow migratory corridor along which most individuals made stops within a network of sites, especially the Bay of Biscay, France and Doñana, Spain. Most sites were used consistently by the same individuals across years. However, sites in Morocco were used during northward migration by 75% of individuals, but not revisited by the same individual across years. After southward migration, a small proportion (15%) of godwits spent the entire non-breeding period north of the Sahara, but most (85%) crossed the Sahara and spent at least part of the non-breeding season among seven coastal sites in West Africa and one site in the Inner Niger Delta. Although site-use patterns varied among individuals, individuals showed high site fidelity and were consistent in the number of sites they used from year to year. The considerable differences in the spatial distribution of individuals that breed within a kilometre of one another raise questions about the causes and consequences of individual migratory differences. We discuss that full annual cycle tracking of juveniles from birth to adulthood is needed to understand the source of these individual differences. Our results on the spatial distribution of godwits throughout their annual cycle lay an important foundation of information that can be used to help conserve this declining species. [ABSTRACT FROM AUTHOR]

The declines in wet-grassland breeding shorebird populations are considered to mainly result from changes in reproduction. While there is plenty of information on nest survival, little reliable information exists on local recruitment due to confounding effects of permanent emigration. Furthermore, few studies have been able to study the roles of pre- and post-fledging survival on local recruitment. Therefore, it is unclear whether local recruitment of young reflects conditions at the breeding sites or at non-breeding sites. We studied an isolated population of the endangered Southern Dunlin (Calidris alpina schinzii) breeding on the west coast of Sweden to examine (1) brood survival (probability of at least one chick fledging) by following broods fates and (2) local recruitment (survival from hatching to 1 year old) using capture-recapture data. We then examined how much of the annual variation in juvenile survival was explained by variation in brood survival. Brood survival was on average 0.58 (annual range 0.08–1.00) and explained 64% of variation in annual local recruitment. Still local recruitment was rather high for a shorebird (0.17, SE = 0.023), which reflects the isolated nature of the study population. Our results suggest that local recruitment seems to be mainly constrained by chick survival during the pre-fledging period. Therefore, management of breeding sites leading to increased brood survival, e.g., reducing predation on chicks, should have strong impacts on local recruitment and local population growth. [ABSTRACT FROM AUTHOR]

THE AUTUMN MIGRATION of Jack Snipe Lymnocryptes minimus was studied using mist-netting at night along a muddy shoreline at Lake Tåkern in southern central Sweden. During ten consecutive autumn seasons ranging from mid-September to mid-November a total of 107 birds were captured, particularly within the first two hours after dusk. The peak of migration occurred in the first ten days of October with the juvenile birds on average passing a few days earlier than the adult birds. We present information on movements and ringing recoveries and review the challenges of ageing the species. We propose that crepuscular mist-netting near wetlands offering important staging grounds may be a suitable method to monitor the migratory movements, and possibly the population dynamics, of this little-studied species. [ABSTRACT FROM AUTHOR]

This study presents an ichnotaxonomical assessment of bird footprints from a coastal plain setting in the Eocene lower to middle Aspelintoppen Formation in Brongniartfjellet and Storvola, Svalbard. These footprints are unique evidence for Paleogene birds from Svalbard and the second evidence of Paleogene avifauna of the Arctic (along with scarce fossil remains from Ellesmere Island). The analyzed footprints are assigned to six ichnotaxa belonging to three ichnofamilies: Aquatilavipes isp., avian footprint morphotype A and B (ichnofamily Avipedidae); Gruipeda cf. G. abeli, Gruipeda cf. G. dominguensis (ichnofamily Gruipedidae); and Gyeongsangornipes isp. (ichnofamily unknown). Associated invertebrate ichnofossils include Helminthoidichnites tenuis, Cochlichnus anguineus, and Helminthopsis isp. The avian footprints reflect small, medium-sized and rare large birds that can be morphologically compared to those of modern relatives including crane, heron, plover, moorhen, gallinule, oystercatcher and curlew. It is also proposed that in situ sets of shorebird footprints showing a preferred orientation, not composing trackways and showing overprinting, can be used as an indicator of the position and orientation of the shoreline. [ABSTRACT FROM AUTHOR]

Migratory animals play vital ecological roles in ecosystems worldwide, yet many species are threatened by human activities. Understanding the detailed patterns of habitat use throughout the migration cycle is critical to developing effective conservation strategies for these species. Migratory shorebirds undertake some of the longest known migrations, but they are also declining precipitously worldwide. To better understand the dynamics of shorebird declines along the East Asian–Australasian Flyway, we quantified the spatiotemporal foraging distribution of 17 migratory shorebirds at two critical stopover sites. We found that shorebirds exhibit substantial interspecific and site-specific differences in their foraging distributions. Notwithstanding these differences, however, the upper tidal flats appear to be especially important to most shorebirds by providing more than 70% of the birds' cumulative foraging time, twofold greater than their proportional area. Because the upper tidal flats are also more prone to coastal development, our findings may help to explain why shorebird populations along the flyway have declined much faster than the overall rate of tidal flat loss. Our work highlights the importance of protecting upper tidal flats to conserve migratory shorebirds and demonstrates the value of a detailed ecological understanding of habitat usage by migratory animals for conservation planning. [ABSTRACT FROM AUTHOR]

Species-specific vocalizations can act as a reproductive isolating mechanism between closely related populations. We analyzed vocal differences between 2 hybridizing species of sex-role reversed polyandrous shorebirds, the Northern Jacana (Jacana spinosa) and Wattled Jacana (J. jacana). We found that Northern Jacana calls have higher fundamental frequency and peak frequency than Wattled Jacana calls. We also compared calls between females and males, as both jacana species are sex-role reversed and females compete for male mates. Males produce calls with a higher fundamental and peak frequency and shorter notes than females. These results suggest that vocal differences between Northern and Wattled jacanas have the potential to act as a behavioral mediator of interspecific interactions, and that sex differences in vocalizations may relate to sex-role reversal in territorial defense and mate attraction. [ABSTRACT FROM AUTHOR]

Stable isotopes are well documented as effective intrinsic markers to infer migratory connectivity which provides key information for establishing an effective conservation strategy in migratory birds. However, there are few studies using stable isotopes that have been applied to long-distance migratory shorebirds globally and such studies are especially scarce along the East Asian-Australasian Flyway. We used stable isotope analysis (δ²H, δ13C and δ15N) to infer breeding and wintering areas and examine the differences in those values among populations of Terek Sandpipers (Xenus cinereus) at stopover sites in South Korea. The range of δ²H in feathers sampled from birds caught in the Korean peninsula at spring and autumn migration stopover sites was consistent with them being grown at sites throughout their flyway as confirmed by leg flag resightings of birds on this flyway. The eastern Siberia region from Yakutsk to Norilsk and Chukotka in Russia was inferred as the most probable breeding area of the population. Papua New Guinea in the Melanesia region, Malaysia and Indonesia were identified as the most probable wintering areas. Isotope values of populations at different stopover sites and different seasons were consistent. These results suggest that stable isotopes can be effectively used alongside other existing methods (e.g. ringing, coloured leg flags, light level geolocation, satellite tag telemetry) to infer the migratory connectivity for long-distance migratory shorebird species that occur over many countries and continents. [ABSTRACT FROM AUTHOR]

In Focus: Reneerkens, J., Versluijs, T. S. L., Piersma, T., Alves, J. A., Boorman, M., Corse, C., ... Lok, T. (2020). Low fitness at low latitudes: wintering in the tropics increases migratory delays and mortality rates in an Arctic breeding shorebird. Journal of Animal Ecology, 89, 691–703. A central question in migratory ecology has been to understand the fitness consequences of individual variation in migration distance among different species and populations. Reneerkens et al. (2020) investigated the demographic consequences of long‐distance migration for Sanderlings Calidris alba, an Arctic‐breeding species of sandpiper. Their study population has a remarkable geographic distribution with a breeding range that is concentrated in northeast Greenland and Ellesmere Island, Canada but a nonbreeding range that extends across 85° of latitude from Scotland to Namibia. The authors report on unexpected patterns of latitudinal variation in three demographic parameters: timing of passage on northward migration, probability of juvenile migration and apparent survival of adults. Sanderlings travelling 1,800–2,800 km to settle at north temperate sites during the nonbreeding season had earlier passage dates, and also higher probabilities of migration and apparent survival. In contrast, birds travelling 6,000–7,800 km to equatorial sites experienced later passage dates, delayed maturity and lower apparent survival. However, if Sanderlings migrated even farther and flew over 11,000 km to nonbreeding sites in Namibia, then their performance was restored to early passage dates and higher survival. Movement tracks from birds tagged with geolocators showed that birds wintering in Namibia make nonstop flights of 7,500 km that bypass West Africa during northward migration. Thus, all lines of evidence suggest that Sanderlings face adversity when spending the nonbreeding season at equatorial latitudes. Moreover, the central finding that components of fitness can have nonlinear relationships with migration distance is a novel discovery that leads to many additional questions. The new findings have broader implications for theoretical models of migration, and for understanding how different patterns of movements may arise or be maintained in migratory species. [ABSTRACT FROM AUTHOR]

The relationship between the rate of predation and prey abundance is an important component of predator–prey dynamics. However, functional responses are less straightforward when multiple predators compete for shared prey. Interactions among competing predators can reduce or enhance effects of predation on prey populations. Because many avian populations experience high rates of nest predation, understanding the role of specific predators on nest mortality will lead to more informed conservation and management strategies which attempt to increase productivity by removing certain predators or managing habitat to limit their impact.Our goal was to evaluate effects of specific predators and the influence of nest abundance on nest mortality.We monitored snowy plover Charadrius nivosus nests across 7 years at two study areas in Utah, USA, with remote cameras. We modelled predator‐specific hazard rates for nest mortality in a Bayesian framework to assess relationships between competing predators and the role of nest abundance on predator‐specific hazard rates.We found that hazard rates for nest mortality by gulls Larus spp. decreased with increasing nest abundance, whereas nest mortality by foxes Vulpes spp. and ravens Corvus corax initially increased, indicating that dietary switching may occur when nests become more abundant. Nest mortalities of specific predators were often not independent and ranged between compensatory (e.g. mammalian mesopredators) and superadditive (e.g. avian predators) across the breeding season.The non‐independence between nest mortalities suggests that reductions in some predators may not translate to additive increases in overall nest success. Analyses of cause‐specific mortality are rarely applied to avian nests, but examination of interacting impacts among competing predators on nest survival may provide insight into specific drivers of avian population dynamics. A free Plain Language Summary can be found within the Supporting Information of this article. [ABSTRACT FROM AUTHOR]

The spoon-billed sandpiper Calidris pygmaea , a migratory Arctic-breeding shorebird, is one of the rarest birds and its population has declined since the 1970s. We surveyed its most important known wintering area in the Upper Gulf of Mottama in Myanmar to estimate recent (2009–2016) changes in its numbers there. The total number of small shorebirds present in the Upper Gulf was counted and the proportion of them that were spoon-billed sandpipers was estimated from sample scans. These two quantities were multiplied together to give the estimated number of spoon-billed sandpipers in each of 4 years. Total numbers of combined small shorebird species tripled from 21,000 to 63,000 between 2009 and 2016, coincident with efforts to reduce hunting pressure on waterbirds. However, the proportion of small shorebirds that were spoon-billed sandpipers declined and their estimated absolute numbers fell by about half, from 244 to 112 individuals. It is probable that loss of intertidal habitat and shorebird hunting elsewhere on the migration route of the spoon-billed sandpipers wintering at Mottama is causing a continued decline, although this is occurring at a less rapid rate than that recorded from Arctic Russia before 2010. The number of spoon-billed sandpipers wintering on the Upper Gulf of Mottama remains the highest single-site total for this species from any known wintering site. Preventing resurgence of illegal shorebird hunting and ensuring long-term protection of the intertidal feeding habitats and roost sites in the Gulf are high priorities if extinction of this species is to be averted. [ABSTRACT FROM AUTHOR]

Trisik Beach is a wetland area located in the southern part of Daerah Istimewa Yogyakarta. Then beach played an important role as shorebirds habitat. The purpose of this study was to analyze the community and food guild for bird communities in the Trisik Beach. This research was conducted in October 2018 - January 2019 using a point count technique. The shorebird community in the Trisik Beach consisted of 22 species which was divided into migratory and residents bird. Guild type of shorebird communities in this area were categorizes into three grup namely mollucivore, insectivore and omnivore. Based on how to get food, Mollucivore guild type food developed into some guild types. The insectivore guild type consisted of one guild type. The Omnivore guild type was developed into ten types. The most commonly found guild type was the omnivore guild type consisted 17 spesies (77%). [ABSTRACT FROM AUTHOR]

Great reed warblers, Acrocephalus arundinaceus , 1 and great snipes, Gallinago media , 2 exhibit a diel cycle in flight altitudes—flying much higher during the day than the night—when performing migratory flights covering both night and day. One hypothesis proposed to explain this behavior is that the birds face additional heating by solar radiation during daytime and hence must climb to very high, and thus also very cold, altitudes to avoid overheating during daytime flights. 1,2 Yet, solar heat gain in birds has been shown to drastically decrease with wind speed, 3,4 and the quantitative heating effect by solar radiation on a bird flying with an airspeed of 10 m/s or more is unknown. We analyzed temperature data from multisensor data loggers (MDLs) 5,6 placed without direct exposure to solar radiation on great reed warblers (the logger covered by feathers on the back) and great snipes (the logger on the leg, covered from the sun by the tail). We found that logger temperatures were significantly higher (5.9°C–8.8°C in great reed warblers and 4.8°C–5.4°C in great snipes) during the day than during the night in birds flying at the same altitudes (and thus also the same expected ambient air temperatures). These results strongly indicate that the heat balance of the flying birds is indeed affected by solar radiation, which is in accordance with the hypothesis that solar radiation is a key factor causing the remarkable diel cycles in flight altitude observed in these two long-distance migrant bird species. 1,2 • Migrating birds are warmer at day than at night when flying at the same altitudes • This indicates that their heat balance is affected by solar radiation at daytime • The birds follow a diel altitude cycle, flying much higher at day than at night • By high and cold diurnal flights, solar heating seems to be counteracted Great reed warblers and great snipes exhibit a diel cycle in migratory flight altitudes, flying much higher during the day than the night. Using logger temperature data, Sjöberg et al. show that birds at the same altitude are warmer during the day than at night, indicating that they climb to cold altitudes to counterbalance solar heating in daytime flights. [ABSTRACT FROM AUTHOR]

Shorebirds (sandpipers, plovers and allies) are some of the most charismatic animals that breed on all continents and inhabit diverse habitats, and their ecology, behaviour and evolution have attracted much attention ever since the work of Charles Darwin. Here I summarise the insights from 30 years of research on shorebird biology to illustrate the contributions of these to four research fields: breeding system evolution, sex ratio research, speciation and biodiversity conservation. Two major conclusions can be drawn from these insights. First, as shorebirds live in a variety of habitats and exhibit puzzling adaptations to their environments, studying their ecology, behaviour and life histories provides novel insights into the emergence and maintenance of organismal diversity. Second, to uncover patterns and processes in evolution, it is both important and stimulating to combine different research methods, and detailed single-species studies with multi-species comparative approach. My main thesis is that curiosity-driven research into the natural history of non-conventional model organisms provides novel insights into fundamental processes in ecology, behaviour and evolution. I also argue that scientific funding should follow the Goldilocks principle: not too little, not too much, just the right amount. [ABSTRACT FROM AUTHOR]

Sea level rise (SLR) and disturbances from increased storm activity are expected to diminish coastal ecosystems available to nesting species by removing habitat and inundating nests during incubation. We updated the United States Geological Survey's (USGS) Coastal Vulnerability Index, which provides a qualitative and relative assessment of a coastal area's vulnerability to erosion and shoreline retreat as a function of SLR and other factors, for the South Atlantic Bight. We considered a eustatic SLR projection of 14 cm by 2030. We linked long‐term survey data for 3 sea turtle species, 3 shorebird species, and 5 seabird species to future coastal erosion vulnerability to SLR to understand effects of future SLR on nesting habitats. Over 2,000 km (43%) of the South Atlantic Bight coastline is projected to have an increase in coastal erosion vulnerability by the 2030s, with respect to its present vulnerability. Future vulnerability of SLR‐induced erosion along the South Atlantic Bight is spatially variable, and the 11 coastal study species also varied in their use of coastal habitats with high future coastal vulnerability to SLR. For example, only 23% of high‐density nesting habitat for the brown pelican (Pelecanus occidentalis) is expected to be at increased vulnerability to SLR, whereas >70% of the high‐nesting density habitat for 2 seabird species (gull‐billed tern [Gelochelidon nilotica], sandwich tern [Thalasseus sandvicensis]) is predicted to have higher future coastal erosion vulnerability by 2030. We provide predictions for the level of susceptibility of the study species to erosion from future SLR, which is the first step in managing coastal species for the changing environmental conditions associated with climate change and SLR. © 2019 The Authors. Journal of Wildlife Management Published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. Erosion from future sea level rise varies along the South Atlantic Bight, and the degree of use of vulnerable habitats varies among 11 coastal study species. Conservation managers can use our broad‐scale approach to align high nesting density habitats with those areas predicted to have high future coastal vulnerability. [ABSTRACT FROM AUTHOR]

Understanding an organism's habitat selection and behavioural flexibility in the face of environmental change can help managers plan for future conservation of that species. Hyperabundant tundra‐nesting geese are influencing Arctic environments through their foraging activities. Goose‐induced habitat change in Arctic wetlands may influence the availability of habitat for numerous shorebird species that breed sympatrically with geese.We explore whether goose‐induced habitat alteration affects shorebird breeding density and nest site selection. Using habitat data collected at sites with High, Moderate and Low goose influence, and samples collected during two periods separated by 11 years, we document the habitat characteristics influenced by geese. We describe the habitat characteristics preferred by shorebirds and relate their availability to goose influence and shorebird density. Finally, we examine whether shorebird nest site selection has changed over time and whether shorebirds select nest sites differently in habitat influenced by geese.We document spatial and temporal changes in sedge meadow habitat and lateral concealment relating to goose influence. The availability of sedge meadow habitat and the degree of lateral concealment declined with increasing goose influence, and also declined at two sites over the 11 years of the study.Densities of both cover‐ and open‐nesting shorebirds were highest where goose influence was lowest. At sites with Low goose influence, cover‐nesting shorebirds selected nest sites with more sedge meadow and concealment than at sites with Moderate and High goose influence, presumably because these high‐quality sites were more available.Synthesis and applications. Intensive foraging by a colony of hyperabundant geese is limiting the availability of preferred nesting habitat and densities of sympatric‐nesting shorebirds. Where goose‐induced habitat alteration is pronounced shorebird species that select concealed nest sites are nesting in areas with lower concealment and less sedge meadow. Studies examining the degree to which these effects scale up to impact the population sizes of declining shorebirds should be considered a future research priority. Moreover, management strategies for geese should incorporate the habitat needs of sympatric species and reinvigorate efforts for goose population reduction in order to achieve the population targets articulated by management agencies. Intensive foraging by a colony of hyperabundant geese is limiting the availability of preferred nesting habitat and densities of sympatric‐nesting shorebirds. Where goose‐induced habitat alteration is pronounced shorebird species that select concealed nest sites are nesting in areas with lower concealment and less sedge meadow. Studies examining the degree to which these effects scale up to impact the population sizes of declining shorebirds should be considered a future research priority. Moreover, management strategies for geese should incorporate the habitat needs of sympatric species and reinvigorate efforts for goose population reduction in order to achieve the population targets articulated by management agencies. [ABSTRACT FROM AUTHOR]

Recent literature has urged the conservation science community to distinguish between human–wildlife and human–human conflict. Mislabelling conflicts is thought to constrain problem definition and hinder appropriate solutions. New to this discussion, we studied how the media is framing conflict. The focus of our research was conflict surrounding conservation of a protected species. The piping plover Charadrius melodus is federally listed as threatened on the Atlantic coast of the USA. Our research focused on characterizing the tone and framing in media coverage of the plover and its conservation. We were interested in how the source of the conflict was framed: are the species itself, policies, or the government agencies administering legal restrictions blamed for the conflict? We analysed 725 articles (199 unique articles, not including those run by multiple media sources) written about the plover in the region during January 2014–September 2015. Articles were analysed qualitatively by two coders. We found the overall tone of the unique articles was most frequently positive towards the bird and/or its conservation (48%), followed closely by neutral (or balanced) articles (46%). Few articles were negative (6%). Nonetheless, framing that blamed a source for the conflict was present in 34% of the unique articles. The plover itself was blamed in twice as many articles as the policies or government agencies enacting the regulations. This framing was also the strongest predictor of article tone. Understanding how the media portrays piping plovers can help guide organizations interested in proactive media relations and other solutions to de-escalate this conflict. [ABSTRACT FROM AUTHOR]

Shorebird populations worldwide are declining because of habitat loss from sea‐level rise, accelerated erosion, development, and recreational land use. To better understand the consequences of human recreational activity, we monitored survival, habitat use, condition, and behavior of pre‐fledged piping plover (Charadrius melodus) chicks on Fire Island and Westhampton Island, New York, 2013–2015. Broods experienced varying levels of recreational land use (low‐use, moderate‐use, high‐use, and high off‐road vehicle‐use), and recreational use was higher on weekends (Friday–Sunday) than weekdays. Chick daily survival rates were lowest on weekends and increased with time since weekend. Chicks that hatched in areas with low recreational use were more likely to survive to fledging (25 days; x¯ = 0.82 ± 0.08 SE) than those that hatched in areas of high recreational use (x¯ = 0.19 ± 0.05). In addition, chicks hatched in areas of high recreational use fledged at a later age than those hatched in areas of low or moderate recreational use. On weekends, chicks spent less time in foraging habitat (with higher prey abundance), less time foraging, and made fewer foraging attempts per minute than they did on weekdays. These results suggest that recreational activity on beaches pushed foraging plover chicks into habitats with lower food availability, resulting in lower feeding rates, slower growth, and decreased survival. Recreational use of coastal areas can limit the functional availability of shorebird foraging habitat, particularly intertidal foraging habitat, resulting in demographic consequences. © 2018 The Wildlife Society. To better understand the consequences of human recreational activity, we monitored survival, habitat use, condition, and behavior of pre‐fledged piping plover (Charadrius melodus) chicks. Chicks that hatched in areas with low recreational use were more likely to survive to fledging than those in areas of high recreational use, and on weekends (when recreational use was highest) chicks spent a lower proportion of their time in higher‐quality foraging habitat, spent a lower proportion of their time foraging, made fewer foraging attempts per minute, and had lower survival than on weekdays. These results are consistent with the hypothesis that recreational use can reduce piping plover reproductive output. [ABSTRACT FROM AUTHOR]