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Monitoring wildlife abundance across space and time is an essential task to study their population dynamics and inform effective management. Acoustic recording units are a promising technology for efficiently monitoring bird populations and communities. While current acoustic data models provide information on the presence/absence of individual species, new approaches are needed to monitor population abundance, ideally across large spatio‐temporal regions.We present an integrated modelling framework that combines high‐quality but temporally sparse bird point count survey data with acoustic recordings. Our models account for imperfect detection in both data types and false positive errors in the acoustic data. Using simulations, we compare the accuracy and precision of abundance estimates using differing amounts of acoustic vocalizations obtained from a clustering algorithm, point count data, and a subset of manually validated acoustic vocalizations. We also use our modelling framework in a case study to estimate abundance of the Eastern Wood‐Pewee (Contopus virens) in Vermont, USA.The simulation study reveals that combining acoustic and point count data via an integrated model improves accuracy and precision of abundance estimates compared with models informed by either acoustic or point count data alone. Improved estimates are obtained across a wide range of scenarios, with the largest gains occurring when detection probability for the point count data is low. Combining acoustic data with only a small number of point count surveys yields estimates of abundance without the need for validating any of the identified vocalizations from the acoustic data. Within our case study, the integrated models provided moderate support for a decline of the Eastern Wood‐Pewee in this region.Our integrated modelling approach combines dense acoustic data with few point count surveys to deliver reliable estimates of species abundance without the need for manual identification of acoustic vocalizations or a prohibitively expensive large number of repeated point count surveys. Our proposed approach offers an efficient monitoring alternative for large spatio‐temporal regions when point count data are difficult to obtain or when monitoring is focused on rare species with low detection probability. [ABSTRACT FROM AUTHOR]

Wildlife biologists monitor the status and trends of American woodcock Scolopax minor populations in the eastern and central United States and Canada via a singing-ground survey, conducted just after sunset along roadsides in spring. Annual analyses of the survey produce estimates of trend and annual indexes of abundance for 25 states and provinces, management regions, and survey-wide. In recent years, researchers have used a log-linear hierarchical model that defines year effects as random effects in the context of a slope parameter (the S model) to model population change. Recently, researchers have proposed alternative models suitable for analysis of singing-ground survey data. Analysis of a similar roadside survey, the North American Breeding Bird Survey, has indicated that alternative models are preferable for almost all species analyzed in the Breeding Bird Survey. Here, we use leave-one-out cross-validation to compare model fit for the present singing-ground survey model to fits of three alternative models, including a model that describes population change as the difference in expected counts between successive years (the D model) and two models that include t-distributed extra-Poisson overdispersion effects (H models) as opposed to normally distributed extra-Poisson overdispersion. Leave-one-out cross-validation results indicate that the Bayesian predictive information criterion favored the D model, but a pairwise t-test indicated that the D model was not significantly better-fitting to singing-ground survey data than the S model. The H models are not preferable to the alternatives with normally distributed overdispersion. All models provided generally similar estimates of trend and annual indexes suggesting that, within this model set, choice of model will not lead to alternative conclusions regarding population change. However, as in Breeding Bird Survey analyses, we note a tendency for S model results to provide slightly more extreme estimates of trend relative to D models. We recommend use of the D model for future singing-ground survey analyses. [ABSTRACT FROM AUTHOR]

Background: The analysis of bird community assembly rules is fundamental to understand which mechanisms determine the composition of bird species in urban areas. However, the long-term variation of community assembly rules has not been analyzed yet. The objectives of this study are (1) to analyze the variation of community assembly rules along rural-urban gradients of three cities in central Argentina and (2) to compare the patterns of community assembly between two periods separated by 6 years. Bird surveys were performed along transects in urban, suburban, and rural habitats during 2011 and 2017. Departures from null models that took into account differences in species richness (standardized effect size, SES) were calculated for functional and phylogenetic diversities. Results: A total of 57 species were recorded. Bird species richness was higher in suburban than in urban and rural habitats. SES of functional diversity increased over the years and was significantly lower in urban habitats than in rural habitats, showing a pattern of functional clustering in the most urbanized areas and functional randomness in rural ones. Phylogenetic diversity was higher in both suburban and urban habitats than rural ones, and the phylogenetic clustering in rural bird assemblages changed to randomness in suburban and urban habitats. Conclusions: Bird communities in urban habitats were phylogenetically random and functionally clustered, evidencing environmental filtering by urbanization. In contrast, bird communities in rural areas tended to be phylogenetically clustered, evidencing that certain clades are adapted to rural areas. The processes structuring bird communities along rural-urban gradients were consistent between the 2 years compared. [ABSTRACT FROM AUTHOR]

Background: Habitat degradation is known to have a major impact on the composition of bird communities, yet how these communities recover following such disturbance is less understood. This study examined bird community changes from pre-logging to recovery over the course of habitat disturbance caused by the development of the Hulu Terengganu Hydroelectric Dam Project in Peninsular Malaysia, between 2007 and 2018. Bird surveys were conducted using point count observations and mist netting in the dam area from the pre-logging phase until the operation phase. Results: It was observed that while bird species significantly declined after large-scale habitat clearance between the pre-logging and construction phases, they showed positive signs of recovery from the inundation to operation phases. These findings indicate that the bird community is still recovering, and the permanent loss of habitat required by most of the original species has not occurred, as evidenced by recolonisation. Bird species composition differed across phases due to varying habitat conditions. The turnover rate and immigration rate (recolonisation and newly recorded species) were higher between the construction and operation phases. It was also observed that insectivorous birds were more heavily affected than others by changes to the landscape, which highlights the versatility, survivability and tolerance of certain species to extreme disturbance and habitat modification. Conclusion: Although the operation phase showed an incremental change in bird species richness due to recolonisation and newly recorded species, this value remains far from that of the pre-logging phase. We predict that bird species recovery will continue to increase for some time before reaching a plateau among the newly created islands, reservoir and catchment area of the dam. [ABSTRACT FROM AUTHOR]

Bird assemblages in arid Australia are often characterized as being highly variable through time in response to boom and bust dynamics, although the importance of habitat in structuring assemblages at a local‐scale is also recognized. We use a novel approach to investigate the importance of rainfall variability in structuring bird assemblages in a resource‐limited environment. Monthly bird surveys were conducted at ten plots for 8 years at a botanical and zoological park in central Australia, including five irrigated plots within a fenced area and five natural plots outside. Irrigation—used to promote growth, flowering, and fruiting of plants—created an artificial resource‐enhanced environment against which the response of birds to natural fluctuations in season and rainfall were compared. Species richness was generally maintained at a higher level in resource‐enhanced plots during dry times but was higher in natural plots when rainfall was high, mainly due to increases in granivores and insectivores. Honeyeaters were consistently more abundant at irrigated plots. Rainfall was important in structuring bird assemblages at all plots; however, assemblages were more stable in irrigated plots and did not respond as dramatically to a period of very high rainfall. The comparative smoothing of fluctuations in the composition and abundance of birds in irrigated areas highlights the importance of primary productivity, normally tied to rainfall, in driving temporal change in arid‐zone bird communities. There was also evidence that different plots in differing habitats supported distinct bird assemblages and that this spatial distinctiveness persisted irrespective of rainfall and determined, to some extent, the response to rainfall. Our study is one of few long‐term studies of arid bird assemblages and highlights the importance of both long‐term cycles of productivity driven by rain and season as well as site differences in the dynamics of arid‐zone bird communities. These insights are particularly valuable as climate change further exacerbates rainfall variability worldwide and initiatives to conserve avifauna in increasingly extreme environments may be required. [ABSTRACT FROM AUTHOR]

Standardized monitoring is critical for conservation because reliable survey data are used to inform the necessity, type, and effectiveness of conservation actions. Many of the avian monitoring data used for conservation are collected by "comprehensive" programs that survey for all species observed; however, there are some species that have low availability for detection during comprehensive surveys and are instead monitored with targeted programs. Unfortunately, those targeted programs are rarely evaluated relative to existing programs and management objectives to inform allocation of effort. We assessed the statistical performance of the comprehensive North American Breeding Bird Survey (BBS), the targeted Canadian Nightjar Survey (CNS), and the two programs combined for the Common Nighthawk (Chordeiles minor). First, we used parameters from the existing datasets to simulate population declines and determined the probability of detecting those declines. Analyses that combined both datasets resulted in higher probability of detecting a 30% population decline (BBS: 38%, CNS: 64%, combined: 69%). Next, we built probability of occurrence models and assessed the predictive performance of those models. Combined analyses had similar predictive performance to the CNS and moderated poor performance of the BBS in the north (mean Cohen's kappa; BBS: 0.40, CNS: 0.46, combined: 0.50). Our results suggest that data from targeted monitoring is important for evaluation of Common Nighthawk population trend and habitat relationships but is best combined with BBS data. Comprehensive and targeted monitoring programs may be better when considered together, and exploration of data combination should become the rule, not the exception. We suggest that the framework we present can be used as a starting point for evaluating targeted monitoring programs relative to defined objectives and existing programs, with the potential to explore hypothetical management scenarios. [ABSTRACT FROM AUTHOR]

Long‐term biodiversity monitoring programs provide important information about species' trajectories and broader environmental change. Often constrained by funding and organisational capability and commitment, monitoring programs need to be optimised to maximise ecological and economic efficiencies, as part of sound adaptive management.The monitoring design requirements for detecting biodiversity trends, across assemblages of species with different traits, can be informed by historical datasets. Using data from a landscape‐scale (c. 2,500 km2) bird monitoring program encompassing 151 sites visited three times annually over 16 years, we used resampling to simulate different monitoring designs. We quantified the capacity of modified monitoring regimes to detect population trends for 65 bird species with different densities, detectabilities and specialisations.The majority (58%) of species exhibited a significant decline in relative abundance, with the ability to detect trends proportional to the length of the time series used for analysis. The percentage of trends detected decreased as survey sites or sessions were dropped from the monitoring dataset. Statistically significant trends remained undetected for an additional 2.5 species for every 10% of sites excluded randomly from the program. As monitoring effort was reduced, the precision of trend estimates for rare species was particularly compromised.Conducting bird surveys every second year would produce better results than an equivalent reduction in effort achieved by surveying only half the sites each year, but could compromise the sustainability of the program. If the number of survey sites were reduced, trend detection would be optimised by retaining the spatial extent of the surveys (i.e. by dropping sites from well‐surveyed regions rather than excluding outlying, isolated sites), but the cost savings of this approach would be small.Synthesis and applications. Reduced monitoring effort will compromise trend detection for rare species or species that are difficult to observe, and declining species that will soon become rare. Consequently, monitoring effort that is considered 'surplus' today could provide critical data for detecting species‐level trends and prioritising conservation interventions in the future. Further, sampling efficiencies are not all‐important; we must also consider the impacts of survey design modification on the social and political sustainability of existing monitoring programs. [ABSTRACT FROM AUTHOR]

Aim: MaxEnt has been widely used to model species' geographic distributions as functions of environmental variables and to predict changes in distributions in response to environmental change. Here, we test the predictive ability of MaxEnt models through time by modelling colonizations and extinctions. Location: North America. Methods: Using data for 21 species from the North American Breeding Bird Survey, we first related avian species' geographic distributions to the spatial variation in environmental conditions. Then, we modelled site‐specific colonizations and extinctions between 1979 and 2009 as functions of MaxEnt‐estimated habitat suitability and neighbourhood occupancy. Results: We found that colonization and extinction probabilities were related to spatial variation in habitat suitability, and to neighbourhood occupancy, in the expected directions. However, change in habitat suitability (which is much smaller through time than through space) is a weak predictor of extinction and worse for colonization. This is because a) for most species and most sites, climatic suitability did not change dramatically between 1979 and 2009, and b) the relationship between colonization or extinction probability and change in climatic variables is very weak (r2 = 0.02). Most colonizations and extinctions are apparently unrelated to climate change. Main conclusions: MaxEnt models apparently capture a real effect of habitat suitability on North American bird species' distributions, but over short and medium time scales, occupancy of neighbouring sites by conspecifics predicts changes in occupancy as well as, or better than changes in climatic habitat suitability, as characterized by MaxEnt. One would not expect species' distributions to track climate change closely. Prediction of species' responses to climate change should 1) recognize that the process of colonization and extinction are not equally well predicted by species distribution models and 2) account for the spatial structure of species' distributions. [ABSTRACT FROM AUTHOR]

With increasing fragmentation of natural areas and a dramatic reduction of forest cover in several parts of the world, quantifying the impact of such changes on species richness and community dynamics has been a subject of much concern. Therefore, this study intends to assess avifaunal biodiversity in fragmented forests. Forest patches between the sizes of 10ha and 700ha were identified in Bhopal Forest Circle (BFC), which covers the Vindhyan plateau. Forest patches were classified based on their size and degree of isolation. A sample of 21 forest fragments was selected using proportional sampling. Bird surveys were conducted using the point count method at each site. Three replicates were taken at each site. Avian species richness of each patch was calculated. The results suggest that species richness is positively associated with the size of the forest patches. Larger forest patches such as Binapur (166ha, Chao 1= 73), Sayar (107ha, Chao 1= 78) and Kalyanpura (133ha, Chao 1= 80) had relatively high species richness, except for patches including Narsinghgarh (393ha, Chao 1= 28) and Singota (184ha, Chao 1= 45) with high levels of anthropogenic disturbance. Smaller forest patches were found to have fewer bird species, although small forest patches with lesser degrees of anthropogenic disturbance such as Lalghati (99ha, Chao 1 = 62), Lasudli (16ha, Chao 1 = 65), Ghot (36ha, Chao 1 = 53), and Nasipur (23ha, Chao 1 =52) were more diverse than other patches. These patches were more protected due to being sacred groves (Lalghati and Lasudli) or under private ownership (Ghot and Nasipur). A total of 131 bird species were recorded from all the sampled forest patches. These results suggest that forest patches embedded in an agrarian landscape play a vital role in conserving biodiversity, hence conservation efforts should also be focused on these forest fragments. [ABSTRACT FROM AUTHOR]

Aim: Mountains are biodiversity hotspots and are among the most sensitive ecosystems to ongoing global change being thus of conservation concern. Under this scenario, assessing how biological communities vary over time along elevational gradients and the relative effects of niche‐based deterministic processes and stochastic events in structuring assemblages is essential. Here, we examined how the temporal trends of bird communities vary with elevation over a 20 year‐period (1999–2018). We also tested for differences in temporal dynamics among habitat types (among‐community variability) and functional groups (within‐community variability). Taxon: 97 species of common breeding birds. Location: Swiss Alps. Methods: We used abundance data from the Swiss breeding bird survey to compute different temporal dynamic metrics (temporal turnover, synchrony, rate of community change and community‐level of covariance among species). We also examined the relative contribution of deterministic and stochastic processes in community assembly using the Raup‐Crick method and the normalized stochasticity ratio. Results: We found that, with greater elevation, temporal species turnover increased while the rate of overall community change over successive years decreased, suggesting that high‐elevation communities display more erratic dynamics with no clear trend. Despite this, we found a more deterministic assembly of alpine communities in comparison to those located at lower elevations. Deterministic processes had greater influence than stochastic processes on community assembly along the entire elevational gradient (80% of communities). Forest communities exhibited higher synchrony in comparison to the remaining habitats likely because they consisted of species with greater functional redundancy, whereas alpine communities were the least stable as a result of their low taxonomic richness ('portfolio' effect). Main conclusions: Community‐level synchrony was overall positive supporting the idea that compensatory mechanisms are rare in natural biological communities. Our results suggest that rather than competition, the existence of differences in the ecological strategies of species may have a stabilizing effect on bird communities by weakening the concordance of species responses to fluctuations in environmental conditions (i.e. enhanced interspecific temporal asynchrony). This study provides evidence that, although species turnover in metacommunities is frequent, a high temporal turnover does not necessarily imply the overriding importance of stochastic processes. [ABSTRACT FROM AUTHOR]

The Juruá River is the third largest white-water tributary of the Amazon River, yet, historically, it has not been considered an important barrier for bird communities. The upper region of the Juruá River was the focus of two ornithological collections in the early twentieth century, but the middle region, where the river and surrounding várzea flooded forest widen, has remained largely unexplored by ornithologists. Inspired by Dr. Emilie Snethlage, whose ornithological expeditions to Amazonian rivers during the early twentieth century were foundational in documenting the importance of river barriers, we undertook a month-long expedition to the middle Juruá River. We collected the first modern specimens, high-quality tissues, and sound recordings of birds from the middle Juruá region. Combining our data with those from previous collections, we present the first comprehensive inventory of bird species from the Juruá region, document several significant range extensions, and report the first evidence that the middle Juruá River acts as a barrier in at least four species complexes of terra firme upland forest birds. Our findings have important taxonomic and biogeographic implications for birds of the Juruá region and southwestern Amazon basin. [ABSTRACT FROM AUTHOR]

The Busa Mountain Range hosts one of the last remaining forests in southern Mindanao, Philippines. Previous bird surveys were confined only to the northern slope, leaving the southern slope in Sarangani Province a relatively understudied area in terms of avian fauna. To augment this gap, we did a rapid inventory survey of bird presence in the Busa Mountain Range employing a combination of line transects, point counts, opportunistic listing, and observation from vantage points, which were supplemented by secondary data from a previous avifaunal assessment. We recorded a total of 116 bird species from 45 families and 88 genera. Despite the significant number in species tally, our survey of birds in the Busa Mountain Range is still inadequate because of the few field sites visited (10 localities) and limited survey time for each locality (82.85 person-hr on average). The presence of several threatened species (DAO 2019-09: 16.37%, n= 19; IUCN V3.1: 13.79%, n= 16), endemic species (53.44%), and anthropogenic disturbance indicate the strong need for protection of the bird fauna and their habitats in the Busa Mountain Range. [ABSTRACT FROM AUTHOR]

Community assembly theory hypothesizes that two main niche‐based processes act to shape composition and organization of biological assemblages: abiotic filtering and biological interactions. Here, we conducted repeated surveys of bird abundance along an undisturbed elevational gradient in the tropical Andes to investigate 1) signals of deterministic processes driving community assembly and 2) potential mechanisms by which these forces operate (temperature, habitat complexity, fruit and insect availability), while correcting for imperfect detection and modeling species abundances with N‐mixture models. We observed strong signals of abiotic filtering driving functionally and phylogenetically clustered assemblages towards higher elevations, and a weaker signal of limiting similarity resulting in few overdispersed assemblages at lower elevations. Whereas the decay in species richness with increasing elevation was explained by temperature, trait and phylogenetic dispersion were explained by both temperature and vegetation structure, implying that an interplay of abiotic and biotic mechanisms determines abundance‐based community structure in our montane assemblages. Interestingly, trait and phylogenetic dispersion consistently decreased until ~3000 m but increased above this elevation, highlighting a potential role of competition in resource‐scarce habitats. Combined, our findings suggest abiotic filters are still the main process shaping montane biotas across elevations, whereas resource availability might act locally upon assemblages further modifying them. Our study challenges recent studies in tropical mountains that suggest that biotic filters are a stronger force than abiotic filters in shaping tropical montane assemblages, and exemplifies how accounting for imperfect detection might overcome potential biases in detecting environmental filtering signals in community assembly studies. [ABSTRACT FROM AUTHOR]

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In several regions of the world, the remoteness of potential bird hotspots and lack of trained observers have often prevented countries from effectively designing proper monitoring schemes at a national scale. For many countries, it is not known whether certain bird strongholds have been missed that should be included for more complete censuses. Such gaps at national scales, sometimes large, may be detrimental for global monitoring schemes. To address this, we used the irregular participation of Sudan to the International Waterbird Census (IWC) as a case study. We designed and tested a method based on remote‐sensing data of the country's lowlands to detect open water bodies in order to develop predictive models of the potential distribution of waterbird abundance and diversity. To identify open water bodies and their flooding duration, we used a Modified Normalized Difference Water Index (MNDWI) derived from Landsat 8 data. Field ornithological surveys were then used as ground‐truth data to estimate the method's accuracy. The statistical results (overall accuracy = 0.972; Kappa index = 0.93) confirmed its effectiveness. Remotely sensed water bodies and additional environmental covariates were then used to build simple habitat models of the distribution of waterbird abundance and diversity based on IWC field survey data. Of the 3119 remotely sensed clusters of open water bodies, three were predicted to host more than 10 000 waterbirds, 89 more than 1000 waterbirds and five more than 30 waterbird species. Located mainly in the southern agricultural floodplains along the main rivers, these predicted waterbird strongholds are therefore recommended for inclusion in the next IWC survey in Sudan. Our findings indicate that using remote sensing to identify open water bodies combined with simple statistical modelling is likely to be a cost‐effective solution to improve IWC sampling and to enhance both waterbird and wetland monitoring in vast under‐surveyed regions. [ABSTRACT FROM AUTHOR]

The continued global biodiversity crisis necessitates the continuation and development of new well‐designed monitoring strategies and action plans with particular focus on under‐represented countries and regions. However, limited resources in terms of budget and availability of qualified field personnel can restrict the geographical coverage of monitoring efforts. Focusing monitoring efforts on a representative subset of species and locations can improve cost‐efficiency. Optimal performance of multi‐species indicators derived from such an approach requires objective methods for species selection and a sampling design that reduces inherent sampling bias caused by regional differences in habitat availability or accessibility. To explore the performance of a multi‐species indicator across different regions within a nation, we developed a multi‐species indicator (MSI) for farmland birds in Norway using objective niche‐based selection of species. We compare the performance of this indicator at national and regional scales (Central and East regions) in Norway, and between urban and rural sites within regions. The seven‐species indicator obtained from the species selection provided similar indicator values and trends for Norway and the Central and East regions, as well as for rural sites within the combined Central + East region. All trends were defined as showing moderate decline from 2007–2016. Urban sites within the combined Central + East region provided trend estimates that showed stronger decline than rural areas in the same region during the time span. Our results emphasize the need to control for sampling bias when structuring monitoring programmes such as a Breeding Bird Survey (BBS). This is especially important if limited resources restrict the geographical coverage of the monitoring scheme. We recommend that monitoring schemes follow a stratified random sampling design that represents both the availability of different land cover types and their distribution with regard to proximity to highly populated areas. If that is not possible, statistically weighting data from different regions or landscapes is likely to be necessary. [ABSTRACT FROM AUTHOR]

Birds with plumage colour aberrations are of interest to both the general public and scientists. However, due to their rarity in nature, information on the presence of colour aberrations is rarely found in the peer‐reviewed literature. Exploration of public observations using modern information technologies such as Internet‐based search engines could facilitate cost‐effective and rapid broad‐scale collection of data on phenotypic aberrations in animals but may also be prone to the same problems as fieldwork, including systematic collection bias. We used Google Images and also asked birdwatchers and ornithologists, via naturalists' forums and social media, to collate a unique dataset of photographs of 936 aberrantly coloured birds of 74 species from Poland. Phylogenetically informed analyses, which included species both with and without reported colour aberrations, revealed that the number of colour aberrations was higher in species with larger populations in Poland, those with larger body size, and those associated with human settlements. Colour aberrations were also more often reported for species with a wider habitat breadth and those which do not migrate over long distances. Habitat openness and diet type were not related to the number of colour aberrations across species in multivariate models. Our study emphasizes not only the power of novel sources to collect large datasets on relatively rare phenotypic aberrations in animals but also the importance of vigilance when using data mined from public sources because the observed patterns may reflect collection bias rather than the nature of the studied phenomena. [ABSTRACT FROM AUTHOR]

Species are reportedly shifting their distributions poleward and upward in several parts of the world in response to climate change. The extent to which other factors might play a role driving these changes is still unclear. Land‐cover change is a major cause of distributional changes, but it cannot be discarded that distributional dynamics might be at times caused by other mechanisms (e.g. dispersal, ecological drift). Using observed changes in the distribution of 82 breeding birds in Great Britain between three time periods 1968–72 (t1), 1988–91 (t2) and 2007–2011 (t3), we examine whether observed bird range shifts between t1‐t2 and t1‐t3 are best explained by climate change or land‐cover change, or whether they are not distinguishable from what would be expected by chance. We found that range shifts across the rear edge of northerly distributed species in Great Britain are best explained by climate change, while shifts across the leading edge of southerly distributed species are best explained by changes in land‐cover. In contrast, at the northern and southern edges of Great Britain, range dynamics could not be distinguished from that expected by chance. The latter observation could be a consequence of boundary effects limiting the direction and magnitude of range changes, stochastic demographic mechanisms neither associated with climate nor land‐cover change or with complex interactions among factors. Our results reinforce the view that comprehensive assessments of climate change effects on species range shifts need to examine alternative drivers of change on equal footing and that null models can help assess whether observed patterns could have arisen by chance alone. [ABSTRACT FROM AUTHOR]

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines. [ABSTRACT FROM AUTHOR]

Audio playback of vocalizations by conspecifics is commonly used to elicit calls when surveying birds of prey. Methods for call surveys vary widely in their use of silent listening periods, and usually range from 3–15 min in length. We aimed to refine this approach for detecting Great Horned Owls (Bubo virginianus) in Arctic Alaska, which is the northernmost limit of their breeding range. We used two playback protocols: protocol 1 entailed uninterrupted playback, whereas protocol 2 interspersed silent listening periods with playback during 12-min surveys. In playback surveys consisting of 166 point counts during the 2017 and 2018 breeding seasons, the probability of detecting a Great Horned Owl was 0.46 (95% CI ¼ 60.09) with protocol 1 and 0.35 (95% CI ¼ 60.12) with protocol 2 (P ¼ 0.18). The probability of detection rose with the length of the playback: of all owls detected during the 12-min surveys, 23% (95% CI ¼ 66.4%) responded within the first 3 min, 52 6 7.6% within the first 6 min, and 80 6 6.1% within 9 min. Including silent listening periods was not necessary for detecting Great Horned Owls during call surveys. We found no correlation between probability of detection and either cloud cover or wind speed (P ¼ 0.60 and P ¼ 0.28, respectively). However, we found a negative correlation between temperature and probability of detection (P ¼ 0.02). From these surveys, we calculated the density of Great Horned Owls in the Middle Fork Koyukuk Valley, Alaska (approximately 67.589°N, 149.789°W) was 4.2 6 2.6 owls/km2 during the winters of 2017 and 2018, which represents the first estimate of density at the northern breeding limit of the species. [ABSTRACT FROM AUTHOR]

In the Indian Himalayan region, community-managed lands such as community-managed forests and agriculture lands play an important role in conserving native biodiversity. Our avifaunal surveys done between 2013 and 2016 recorded 205 species belonging to 52 families. Two species were first records from Pithoragarh district. Six species are classified as Threatened and five as Near Threatened in the IUCN Red List. Six are Schedule-I species under the Indian Wildlife (Protection) Act, 1972. In total, 63 migratory (local/altitudinal and long-range) and 81 Himalayan endemic species were observed. Overall, our observations reveal a niche providing both transient and perennial havens for resident and migrant avifauna in our study site's landscape. Our findings suggest that despite human persistence in the landscape, diversity within avifaunal guilds is rich in the community-managed lands. We recommend further research to focus on understanding the factors governing the bird distribution and co-occurrence in the landscape. [ABSTRACT FROM AUTHOR]

The status and trend estimates derived from the North American Breeding Bird Survey (BBS) are critical sources of information for bird conservation. However, the estimates are partly dependent on the statistical model used. Therefore, multiple models are useful because not all of the varied uses of these estimates (e.g., inferences about long-term change, annual fluctuations, population cycles, and recovery of once-declining populations) are supported equally well by a single statistical model. Here we describe Bayesian hierarchical generalized additive models (GAMs) for the BBS, which share information on the pattern of population change across a species' range. We demonstrate the models and their benefits using data from a selection of species, and we run full cross-validation of the GAMs against 2 other models to compare the predictive fit. The GAMs have a better predictive fit than the standard model for all species studied here and comparable predictive fit to an alternative first difference model. In addition, one version of the GAM described here (GAMYE) estimates a population trajectory that can be decomposed into a smooth component and the annual fluctuations around that smooth component. This decomposition allows trend estimates based only on the smooth component, which are more stable between years and are therefore particularly useful for trend-based status assessments, such as those by the International Union for the Conservation of Nature. It also allows for the easy customization of the model to incorporate covariates that influence the smooth component separately from those that influence annual fluctuations (e.g., climate cycles vs. annual precipitation). For these reasons and more, this GAMYE model is a particularly useful model for the BBS-based status and trend estimates. [ABSTRACT FROM AUTHOR]

Automatic bird detection in ornithological analyses is limited by the accuracy of existing models, due to the lack of training data and the difficulties in extracting the fine-grained features required to distinguish bird species. Here we apply the domain randomization strategy to enhance the accuracy of the deep learning models in bird detection. Trained with virtual birds of sufficient variations in different environments, the model tends to focus on the fine-grained features of birds and achieves higher accuracies. Based on the 100 terabytes of 2-month continuous monitoring data of egrets, our results cover the findings using conventional manual observations, e.g., vertical stratification of egrets according to body size, and also open up opportunities of long-term bird surveys requiring intensive monitoring that is impractical using conventional methods, e.g., the weather influences on egrets, and the relationship of the migration schedules between the great egrets and little egrets. [ABSTRACT FROM AUTHOR]

A seven-day survey of birds was carried out in the Budalang’i Flood Plain area in May 2019. Twenty line transects totalling 24.83 km in length were covered using the distance sampling technique. A total of 6149 individuals of 151 bird species were recorded. Species associated with farmlands (Ploceus pelzelni and Columba guinea) and wetlands (Anastomus lamelligerus) were the most frequently encountered and numerous. The Oluhongo Swamp, which is part of the northern extension of Yala Swamp Important Bird Area, had the highest species richness and diversity. Papyrus endemics and threatened swamp-dependent species such as Laniarius mufumbiri, Cisticola carruthersi, Crithagra koliensis, Muscicapa aquatica, Acrocephalus gracilirostris and Bradypterus carpalis were recorded. Two individuals of the Endangered Balearica regulorum were recorded as well. No Palaearctic migrant species were recorded as it was outside the migration period. Habitat loss and pressure resulting from drainage of swamps to reclaim land, strengthening of dykes to reduce the impact of the floods, pollution and extension of agricultural activities continue to threaten the future existence of these endemic and endangered species. [ABSTRACT FROM AUTHOR]

Citizen science monitoring of common birds often involves volunteers visiting selected survey locations twice per year, with interannual differences in the number of birds detected used to infer population trends. Two processes, changes in the timing of migration and breeding in response to climate change, and changes in the timing of surveys by volunteers, may cause variation in the number of birds detected, leading to biases in inferred population trends. We assessed the magnitude of potential biases using the UK Breeding Bird Survey, comparing survey timing, species phenologies and apparent trend biases between 1994–98 and 2013–17. To control for large-scale geographic effects, we focussed on a subset of 888 surveyed 1 km squares in South-East England. Survey dates became significantly earlier, advancing by 2–4 days on average. We calculated seasonal patterns of bird abundance for 68 species. After standardising these to remove long-term abundance trends, median detection dates were advanced by 0.82 days on average. At the species level, the majority of changes were ± 2 days and only five species showed a significant advancement in median detection date. However, species' phenological changes alone are capable of inducing between an 8% suppression and 21% enhancement of species' trends, although the majority are ± 2%. Effects of a similar magnitude are apparent if survey timings are also allowed to change, although different species are affected. Small modifications to the statistical model used to generate trends can control for changes in survey timing, but without additional survey visits, or using data from other sources, we cannot currently control for seasonal variation in detectability. Although the average effects shown here are small, biases could become increasingly important for some species, and we recommend organisers of biodiversity monitoring schemes assess whether their methods are resistant to variations in species phenology and survey timing. [ABSTRACT FROM AUTHOR]

MASS CONCENTRATIONS of birds, or the lack thereof, is a phenomenon of great ecological and domestic significance. Apart from being and indicator of, e.g., food availability, ecological change, and population size, it is also a source of conflict between humans and birds. By attracting the attention of the public--either as a spectacular phenomenon or as an unwelcome pest--they also form the public perception of birds and their abundance. In the context of the mass concentration of Bramblings Fringilla montifringilla in Sweden during the winter 2019-2020, this work reviews the literature on this striking phenomenon. I found that winter roosts amount to about one million birds per hectare of roost area, but the variation between reports is significant. There is support for roosts of up to around 15 million Bramblings, but much larger numbers are frequently cited in the literature. I discuss difficulties related to the assessment of mass concentrations, and argue that reports of very large numbers should always be carefully scrutinized. [ABSTRACT FROM AUTHOR]

THE COASTAL AREAS of the island of Gotland in the center of the Baltic Sea is an important wintering site for waterbirds in Sweden. Gotland offers extensive areas of shallow feeding grounds and, due to its location, some open waters remain available even during harsh winters. Wintering waterbirds have been counted annually on the island since the start of the international waterbird counts in 1967, with full coverage of all the inshore areas around the main island obtained during the years 1969-1978 and 2013-2020. Between these two periods, the mean total number of wintering waterbirds increased from 32,000 to 111,500. The most numerous species were Mallard Anas platyrhynchos, Tufted Duck Aythya fuligula, and Common Goldeneye Bucephala clangula. Some species such as Eurasian Wigeon Mareca penelope, Eurasian Teal Anas crecca, and Gadwall Mareca strepera started to winter during the second period. Marked increases were also found for Smew Mergellus albellus and Greater Scaup Aythya marila, likely related to progressively milder winters in recent years. [ABSTRACT FROM AUTHOR]

SPECIES-SPECIFIC TRACKS of animals can be an effective way of mapping species that are hard to find even if they are present. We used observations of sap rows on trees to calculate densities of Eurasian Three-toed Woodpeckers Picoides tridactylus. We surveyed 14 fixed routes in northern Sweden below the montane forest for sap rows during the autumn of 2020. We used our observations of fresh sap rows together with average home range and proportion of active territories per year derived from the literature, to calculate large-scale woodpecker population density. The density based on sap rows was 0.19 pairs per km². Densities from fixed route bird observations for different parts of Västerbotten County below the montane forests were 0.13-0.14 pairs per km², in relative agreement with the estimates from sap rows. We also calculated the population density from fixed route observations in the montane forests, and these were almost three times higher. Our density calculations correspond to 7,900 pairs in Västerbotten County. These results indicate that systematic counts of sap rows can quickly provide credible population density estimates of Eurasian Three-toed Woodpeckers. [ABSTRACT FROM AUTHOR]

Openly available species observation records on various online platforms achieve good coverage in urban areas. Thus, such digital data could provide a basis for biodiversity assessments in cities. Here, we investigated suitability of open digital species occurrence data, compared with systematically field surveyed data, in Freiburg, Germany (a Western city) and Dhaka, Bangladesh (a global-South city). We focused on resident bird species richness as an indicator of local biodiversity. We collected avian records for urban areas from 'ornitho.de' in Freiburg and 'gbif.org' in Dhaka. Additionally, we conducted point count surveys at several urban locations in both cities. Using these records, we prepared three grid (cell size 250 m × 250 m) based datasets—open digital dataset (i.e. records compiled from well-surveyed grid cells), field surveyed dataset (i.e. records of systematic bird surveys) and combined dataset (i.e. digital data and field data combined). We compared the relationship of resident bird richness with different habitat factors by applying linear regression models, separately using each of the three datasets. We assessed suitability of data from online platforms by comparing the variables retained after model selection based on digital data versus field surveyed data. We found that field surveyed data and combined data did not alter general understanding of the key driving factors of bird richness patterns we obtained from open digital data. This held for both case examples, Freiburg vs. Dhaka, respectively. This suggests that open digital data from well-surveyed urban locations can provide a suitable basis to assess drivers of biodiversity patterns within cities. [ABSTRACT FROM AUTHOR]

We assessed the structural complexity of vegetation, birds and soundscapes in two areas of Braulio Carrillo National Park, Costa Rica, with different road exposure, as baseline information for conservation and management. We measured vegetation structure complexity, surveyed birds and recorded soundscapes in an area adjacent to the National Highway 32 (Quebrada) and another area 20 km away (Ceibo). Quebrada presented a more open forest structure and lower density of trees and shrubs; lower evenness and higher acoustic complexity, higher bioacoustic activity and sound pressure level; higher bird abundance and richness. Ceibo showed a higher density of trees and shrubs, higher complexity of vegetation structure, higher proportion of biophonies than anthrophonies, and an acoustic community with higher diversity and entropy. The study sites differed in characteristics of their bird communities in an unexpected way; these differences appear to be mostly influenced by the structure and complexity of the vegetation surrounding the road. However, the soundscapes seemed to properly reflect the habitat condition, and are promising for evaluating the ecological condition of a site. [ABSTRACT FROM AUTHOR]

The paper presents the ecological characterization of the flora and fauna from a part of the protected area RO-SPA 0143 Upper Tisza NATURA 2000 located in Săpânţa, a well known tourist village in Maramure? county, Romania with special attention on birds species. The area is of great interest due to the secular oak forest where is located one of the tallest wooden constructions in the world, Peri Monastery a special architectural and spiritual tourism objective. The oak forest and the the surrounding areas host a large biodiversity of flora and avian fauna that is put in danger by anthropic pressure. It is essential to give priority to the conservation and protection of flora and fauna in this area. This paper includes the results related to the area of Săpânţa, within a larger study, which aims to create an inventory of bird species in the RO SPA 0143 -Upper Tisza protected area and assess in detail their conservation status. The work is of great interest due to the presentation of the vegetation in the oak forest area and in its proximities highligting the present threats for biodiversity as well as due to the inventory of 104 species of birds whose habitat has been identified in Săpânţa and in the neighboring areas. Monitoring of forest and their surroundings showing its important functions on biodiversity could provide valuable information necessary to support managers and local authorities to conserve, protect and sustainably manage these areas. [ABSTRACT FROM AUTHOR]

Context: Biodiversity in tropical region has declined in the last decades, mainly due to forest conversion into agricultural areas. Consequently, species occupancy in these landscapes is strongly governed by environmental changes acting at multiple spatial scales. Objectives: We investigated which environmental predictors best determines the occupancy probability of 68 bird species exhibiting different ecological traits in forest patches. Methods.: We conducted point-count bird surveys in 40 forest sites of the Brazilian Atlantic forest. Using six variables related to landscape composition and configuration and local vegetation structure, we predicted the occupancy probability of each species accounting for imperfect detections. Results: Landscape composition, especially forest cover, best predicted bird occupancy probability. Specifically, most bird species showed greater occupancy probability in sites inserted in more forested landscapes, while some species presented higher occurrence in patches surrounded by low-quality matrices. Conversely, only three species showed greater occupancy in landscapes with higher number of patches and dominated by forest edges. Also, several species exhibited greater occupancy in sites harbouring either larger trees or lower number of understory plants. Of uttermost importance, our study revealed that a minimum of 54% of forest cover is required to ensure high (> 60%) occupancy probability of forest species. Conclusions: We highlighted that maintaining only 20% of native vegetation in private property according to Brazilian environmental law is insufficient to guarantee a greater occupancy for most bird species. We recommend that policy actions should safeguard existing forest remnants, expand restoration projects, and curb human-induced disturbances to minimise degradation within forest patches. [ABSTRACT FROM AUTHOR]

Extensive wetland habitat loss across the continental United States has caused post-harvested rice fields to become an important surrogate wetland habitat for migratory waterfowl. Flooded rice fields used by waterfowl have the potential to provide agronomic benefits to soil. Increasing interest in the reciprocal relationship between birds and flooded rice fields has given rise to many studies that aim to quantify bird abundance. However, surveying large flocks of birds in open agricultural fields is challenging because traditional ground and aerial surveys can cause birds to flush or re-allocate spatially, thus biasing counts that are reflected in following management practice recommendations. To avoid this, we used camera surveys and an open-access image manipulation program to estimate 24-h bird use of rice fields. Indices of bird abundance from counts were used to estimate fecal matter input to rice fields. Camera surveys have the potential to limit biases seen in other methods because of their ability to capture bird use over a 24-h period over an entire season and the ability for multiple researchers to survey the same site. • Surveying bird flocks by traditional ground or aerial surveys can bias bird abundance estimates. • Camera surveys of waterfowl in rice fields were used to estimate bird abundance and fecal matter input. • Camera surveys reflect static bird use over 24-h which can lower bias seen in traditional methods.

During standardised bird surveys in September 2021 in the West Kimberly, two independent observations of an orange pigment variety in a male Black-bellied Crimson Finch Neochmia phaeton phaeton were recorded. This is the first documented observation of a wild Black-bellied Crimson Finch with this coloration. [ABSTRACT FROM AUTHOR]

Piscivorous birds are the primary source of catfish (Ictalurus spp.) depredation at aquaculture facilities in northwestern Mississippi. Of particular concern is the Double-crested Cormorant (Phalacrocorax auritus), which can cost aquaculture producers millions of dollars annually through the depredation of cultured fish. Historical research conducted in the early 2000s estimated cormorant use of aquaculture ponds in the region, but aquaculture area has decreased by more than 70% since those estimates were made. With less aquaculture available, we predicted cormorant densities on aquaculture would be greater today than historically. Applying a similar methodology as in historical studies, we used aerial surveys to collect data on cormorants at night roosts and using catfish aquaculture ponds during 3 consecutive winter seasons, beginning in 2015. Although the mean annual number of cormorants at roosts in the Delta during our study was 64% less than historically, we found no significant change in densities on aquaculture, suggesting that aquaculture area is likely the factor influencing cormorant occurrence in northwestern Mississippi. During contemporary surveys we also measured the abundance of Great Blue Herons (Ardea herodias) and Great Egrets (A. alba) on the aquaculture clusters, and built predictive models of abundance relative to variables associated with forage at and surrounding the clusters. We found abundance of all 3 species was strongly related to the amount of aquaculture area both within and surrounding a cluster, although patterns varied by species. Cormorant abundance was also greater on clusters with proportionately more food fish (≥20 cm in length) than fingerlings (<20 cm) and was positively related to the proximity and size of night roosts. The relationships described here can be used by producers and wildlife managers to predict the abundance of these piscivorous birds at aquaculture facilities and to design efficient management plans to mitigate potential impacts of depredation and disease. LAY SUMMARY Mississippi contains ∼60% of all catfish production in the U.S., and bird depredation costs producers millions of dollars annually. We studied how Double-crested Cormorants, Great Blue Herons, and Great Egrets use commercial catfish aquaculture in Mississippi. However, catfish production in Mississippi has declined by over 70% since its peak in the early 2000s, raising questions regarding bird use, particularly by cormorants. Does less aquaculture mean more cormorants per pond? Has the aquaculture decline affected cormorant abundance in the region, and is catfish aquaculture a driver of local bird abundance? To address these questions, we compared surveys of cormorants from the early 2000s with contemporary surveys. We found fewer cormorants in Mississippi today than in the past but cormorant density on ponds has not changed, suggesting a link to the amount of catfish ponds. Local abundance of all fish-eating birds surveyed was also related to the amount of catfish aquaculture. [ABSTRACT FROM AUTHOR]

In Argentina, the Variable Hawk (Geranoaetus polyosoma) inhabits the northwestern, central, and southern parts of the country, but current information on its breeding distribution and conservation status for most Argentine provinces is lacking. Raptor nest surveys in Santa Cruz Province (southern Argentine Patagonia) during the breeding seasons of 1980–1981 and 2008–2011, revealed six active nests (one in 1980, two in 2008, and three in 2010), plus one additional nest (in 2011) showing evidence of use earlier in the breeding season. Additional ornithological surveys in Santa Cruz Province between 1994 and 2018 revealed two more nests (one each in 2002 and 2004). Results of these combined surveys suggest that the Variable Hawk breeds in very low numbers in the southern continental Patagonian steppes, grasslands, and coastal biomes of Santa Cruz Province. This low density substantiates previous reports on the rarity of the species in this province and contrasts with findings from northeastern Patagonia, where it breeds at high densities. Low Variable Hawk breeding abundance in southern continental Argentine Patagonia is likely related to low prey diversity and abundance as well as anthropogenic activities. We recommend surveys be conducted of this hawk and its prey in different biomes throughout Patagonia. [ABSTRACT FROM AUTHOR]

The bird life of the central Peruvian Amazon is poorly known. To better characterize bird diversity and distributions, we conducted 4 expeditions to this lowland area, totaling 114 field days in 2015, 2018, and 2019. We focused on sampling under-surveyed habitats, terra firme in multiple interfluves, and sites around a recent river avulsion, and we detected 657 bird species across 22 study sites. Our results include the first extensive inventories of blackwater wetland systems, Guadua bamboo tracts, and riverine islands in central Peru; revised information on distributions with respect to river barriers, including documentation of contact and putative hybridization between parapatric forms; 28 first regional records; and new details on poorly known taxa. Together, these results provide a more complete picture of avian diversity in an area characterized by high species richness, high habitat diversity, and biogeographic interchange. [ABSTRACT FROM AUTHOR]

Diurnal raptor habitat use has conservation implications due to environmental and anthropogenic interactions. Three tree‐nesting diurnal raptors, black kites (Milvus milvus), steppe buzzards (Buteo vulpinus) and African fish eagles (Haliaeetus vocifer), were studied from December 2016 to October 2017. The objective was to determine factors influencing diurnal raptor habitat selection and use in and around Chembe Bird Sanctuary of Kalulushi district, Zambia. We surveyed for birds in ten randomly selected 200 × 200 m sample plots in each of the five stratified sampling units (miombo woodland, grasslands, human settlements, Lake Chembe and marsh). Seasons and dietary composition variably influenced the distribution, habitat selection and use by raptors. The three raptors devised a suit of behaviours to curtail challenges associated with seasonal food and water availability, and anthropogenic disturbances. There is a need to promote multi‐stakeholder engagement and involvement in raptor conservation. [ABSTRACT FROM AUTHOR]

In Indonesia, the songbird trade is causing serious declines in many native species. Much of this trade is unregulated or illegal but nevertheless occurs openly in physical wildlife markets and online. Here, we report on the trade in a once common songbird, the Sunda laughingthrush (Garrulax palliatus), using compiled market data from 365 bird market surveys across a 30-year period. We found a total of 5,281 birds for sale, with the species encountered in roughly two-thirds of the visits. We observed a significant decrease in the number of Sunda laughingthrushes offered over time from ~ 50 birds/survey in the 1990s to ~ 20 birds/survey in the 2000s and < 10 birds/survey in the 2010s, as well as a significant increase in the market price of the species, suggesting declining populations. In line with the countrywide findings, we found a decrease in the number of the species in the bird markets of Medan, but we did not find a similar decrease in Jakarta, suggesting a complex pattern of availability and demand. Nevertheless, this study shows that continued trapping for trade, if left unchecked, poses a significant risk to the species. We conclude that a more proactive stance from the government, including increasing levels of protection and enforcement of existing regulations, community engagement and possibly targeted captive breeding may alleviate the pressure on remaining wild populations. Our study offers a model whereby analysis of wildlife trade over extended periods of time covering vast geographic regions may offer insights that are easily missed when working in a too focused manner on single markets over short periods of time. [ABSTRACT FROM AUTHOR]

Grassland birds were surveyed in two mountain pastures (Zaprikraj and Zapleč) in the southern part of the Julian Alps, Slovenia. The survey was carried out during the mornings between 26 and 30 June 2005. Due to the incomplete survey (only one visit, no nocturnal or targeted surveys and late season survey), the surveyed birds' breeding density is only a rough estimate. 167 pairs belonging to 12 species were counted, with Tree (average density of 1.64 p/10 ha) and Water Pipit (average density of 1.60 p / 10 ha) being the most abundant. Both were observed in all altitudinal belts. The highest density in individual altitudinal belt was calculated for Red-backed Shrike Lanius collurio (3.78 p/10 ha) and Water Pipit (3.61 p/10 ha). In well preserved grasslands in the study area, most species reached high breeding densities compared to other parts of Slovenia and all were recorded higher than during the 1992 survey, although still mostly within limits of the elevations elsewhere in Slovenia. Breeding density of Skylark Alauda arvensis decreased with the elevation. Whinchat Saxicola rubetra, Skylark and Red-backed Shrike used significantly gentler slopes, while Pipits showed no preference for particular slopes. [ABSTRACT FROM AUTHOR]

Aim: Under a global change scenario, research focused on changes in assembly patterns over spatial and temporal axes is paramount. Despite an increasing need to assess whether associations among diversity and community metrics change in relation to environmental heterogeneity, the way in which community assembly rules vary across habitats has been hardly explored. Here, we tested for differences in patterns of functional diversity (FD) and phylogenetic diversity (PD) between farmland and forest bird communities in order to improve our understanding about how biological communities respond to anthropogenic disturbances. Location: Continental France. Taxon: 107 species of common birds. Methods: We used an extensive dataset (13 years; 7,115 bird communities) from the French Breeding Bird survey in conjunction with a matrix of 142 functional traits (including information on habitat, diet, life‐stories, behaviour and morphology) to compute different metrics of FD and PD and examine how these vary between habitat types and across time. Results: We found that farmland assemblages showed higher FD and PD than forest assemblages, which were phylogenetically clustered. Both FD and PD of forest assemblages increased with increasing species richness, whereas in farmland assemblages the relationship was asymptotic in both cases. This pattern may be due to the accumulation of generalists, which can end up displacing specialist species when the environment becomes oversaturated triggering a decline in diversity. Contrary to expectations, FD and PD of farmland assemblages increased over the study period, whereas forest assemblages showed a non‐linear pattern. Farmland and forest assemblages also showed divergent trajectories over time in relation to FD metrics. Main conclusions: Although farmland intensification led to a sharp decline in populations of farmland birds, agricultural landscapes in southern Europe still harbour diversity‐rich communities probably due to the legacy effects of past land‐use (traditional practices). Our study highlights the need to take into account the influence of historical landscape configurations when assessing the effect that contemporary land uses have on biotic communities. [ABSTRACT FROM AUTHOR]

Khukh Lake, an Important Bird Area (IBA) within the Mongol Daguur Ramsar Site, is the biggest saline lake in eastern Mongolia. Wetlands in eastern Mongolia play a key role by providing outstanding breeding and stopover sites for migratory waterbirds, in particular those of the East Asian-Australasian Flyway. We surveyed bird community of Khukh Lake in three consecutive surveys (April-May, June- July and September, corresponding to northward migration, breeding and southward migration) in 2016. We counted and recorded varied number of individual waterbirds (26,021 birds) that belong to 49 species from five orders during these surveys. Of these, 88.6% of total counted waterbirds were Anseriformes, while 22 out of 49 species were Charadriiforms, with predominance of waders (17 species). According to this and previous studies, we highlight the crucial threats threatening avifauna at Khukh Lake. These included harvesting aquatic invertebrates, steppe fires, overgrazing and illegal fishing recorded at Khukh Lake. [ABSTRACT FROM AUTHOR]

The Macleay River estuary, situated on the NSW mid-north coast, has not been the subject of systematic shorebird population surveys. To obtain information on the shorebird population and important habitats for migratory and threatened shorebirds, Kempsey Shire Council initiated shire-wide population surveys during the 2018 / 2019 non-breeding season. Surveys were undertaken by two observers using a boat and 4WD vehicle to access estuarine, floodplain, and ocean beach habitats. Five, three-day surveys were conducted between 5 December 2018 and 22 February 2019. Twenty species of shorebird, consisting of eight resident and 12 migratory species, were recorded. The maximum shorebird population estimate over the sample period was 1822 individuals, with between 1068 and 1478 individuals recorded during individual surveys. The most abundant species were Sharp-tailed Sandpiper Calidris acuminata (951 individuals), Black-winged Stilt Himantopus himantopus (330 individuals), and Pacific Golden Plover Pluvialis fulva (211 individuals). Federally-listed threatened species recorded include Far Eastern Curlew Numenius madagascariensis (25 individuals), Bar-tailed Godwit Limosa lapponica (25 individuals), and Curlew Sandpiper Calidris ferruginea (1 individual). State-listed threatened species included Australian Pied Oystercatcher Haematopus longirostris (12 individuals), Sooty Oystercatcher Haematopus fuliginosus (10 individuals), and Broad-billed Sandpiper Calidris falcinellus (1 individual). Based on the 2018 / 2019 counts, the Macleay River estuary and nearby floodplain support an internationally significant population of Sharp-tailed Sandpiper Calidris acuminata and a nationally significant population of Pacific Golden Plover Pluvialis fulva. Floodplain wetlands may be particularly important for both species. [ABSTRACT FROM AUTHOR]