Bird Survey Research Articles

Landscape structure influences the spatial distribution of urban bird attractiveness

ContextLandscape change affects biological diversity and the distribution of species traits related to spiritual, educational, and recreational benefits people derive from nature. These traits are associated with color, song and behavioral characteristics that influence people's perceptions of how attractive an assemblage is. However, the environmental variables that affect the spatial distribution of traits related to the attractiveness of biological diversity remain unexplored.ObjectivesWe tested how landscape structure influences patterns of perceived bird attractiveness (trait diversity associated with colorfulness, behavioral and song categories) across an urbanization gradient.MethodsWe used data from standardized surveys of birds and landscapes within 42 landscape units of 1km2 across the city of Brisbane in eastern Australia. We used structural equation modeling to test effects of landscape composition (built infrastructure, percentage of tree cover) and landscape configuration (fragmentation of tree cover) on mean bird community attractiveness. Relationships between individual traits and landscape structure were analyzed using multinomial logistic regression models.ResultsOur analysis across 82 bird species shows that the relative amount of built infrastructure in a landscape interacts with fragmentation to reduce the overall attractiveness of the landscape’s bird assemblage. However, built areas can exhibit high overall bird attractiveness where there is (1) reduced fragmentation and (2) increased diversity of vegetation structure that provides key habitats for many colorful species with a high diversity of calls. Relationships between bird attractiveness and landscape structure change when they are analyzed at the guild level (insectivores vs frugivores/nectarivores). In addition, body size moderates the effects of landscape structure on song complexity, personality, and color.ConclusionsSmall bodied, colorful and melodious species are negatively affected by built infrastructure and fragmentation. By learning how habitat loss and fragmentation affect the distribution of species-rich, attractive bird assemblages, our findings can inform how urban landscapes might be structured to increase people’s connection with nature.

Environmental Factors Affecting Spatio-Temporal Distribution of Crop-Exploiting Species: Implications for Coexistence Between Agricultural Production and Avifauna Conservation in Wetlands

Bird communities in agroecosystems bring both ecosystem services (e.g., pollination) and disservices (e.g., crop exploitation) to farmers. However, in the proximity of wetland reserves, farmers disproportionately experience harvest yield loss due to large aggregation of bird species that can utilize various agricultural resources. This often results in negative human–wildlife interactions which lower conservation support among farmers. Knowledge about the distribution of avian species that negatively influence yields, and its environmental drivers is thus fundamental to reconcile crop production and bird conservation. This study aims to examine the spatio-temporal patterns in richness and abundance of bird species known to cause agricultural yield loss as well as species-specific distribution patterns for the six bird species that are most challenging for local farmers. In combination with interview surveys of local farmers (n = 367) and seasonal bird surveys (n = 720), we investigated distribution of crop-exploiting avian species in the Indawgyi wetland ecosystem in Myanmar. Our results showed high richness and abundance of crop-exploiting species in the water habitat across all seasons, with most challenging species exhibiting higher presence closer to these water sources. The crop phenology had positive effect on species richness and abundance during the growing season. The agricultural use of crop-exploiting species was season- and species-specific, where the presence probability in the agricultural habitat was higher in habitat generalists than wetland specialists. Therefore, we suggest improved management of natural wetland habitats (e.g., habitat restoration), sustainable coexistence mechanisms in farms close to water (e.g., bird-friendly rice farming and Ecolabel certification) to reduce avian impacts on the farming communities and, at the same time, to promote bird conservation in wetlands of international importance.

Low-intensity urbanisation alters community composition across multiple trophic levels on Lipsi Island, Greece.

Urbanisation has reduced the abundance and diversity of many taxonomic groups, and the effects may be more pronounced on islands, which have a smaller regional species pool to compensate. Green spaces within urban environments may help to safeguard wildlife assemblages, and the associated habitat heterogeneity can even increase species diversity. Here, total abundance and species diversity of butterflies, birds, and vegetation at nine rural and nine urban locations were quantified on Lipsi Island, Greece. Sites were assessed using Pollard walks for butterflies, point-count surveys for birds, and quadrats for vegetation. There was no significant difference in the abundance or species diversity of butterflies or vegetation among rural and urban locations, which could pertain to the low building density within urbanised areas and the minimal extent of urbanisation on the island. However, urban areas hosted a significantly greater abundance, richness, and diversity of birds compared to rural sites. The community composition of butterflies, birds, and vegetation also differed significantly between urban and rural locations, highlighting the impact of urbanisation on species across a broad range of trophic groups. This study contributes to ecological knowledge on the impacts of urbanisation across multiple trophic levels in island ecosystems, with comparisons across a gradient of island size and urbanisation intensity needed in future research.

Diversity and dominance in bird assemblages across habitats in the Ñeembucú wetlands complex

AbstractUnderstanding how diversity responds to habitat heterogeneity in a landscape is a central issue for implementing effective conservation plans. In this study, we analyzed how the composition and abundance of neotropical bird assemblages vary among habitats in the Ñeembucú Wetlands Complex, the largest wetland system in Paraguay. Bird surveys were conducted during 1 year within dominant habitats in the landscape: riparian forests, natural grasslands, savannas, and anthropized sites. The Ñeembucú Wetlands Complex showed a high bird richness (209 species) that contrasted with a pattern of dominance by a small set of 16 species that comprised half of the abundance. This set of oligarchic species consists of generalist species that exploited a wide variety of habitats and were well adapted to human disturbance, contributing to an important overlap in the composition of assemblages. However, despite this overall similarity, there is still significant differentiation in bird assemblages, especially between habitats with the most contrasting vegetation physiognomy. Riparian forests and savannas showed higher diversity values than the more structurally homogeneous grasslands. Also, all natural habitats showed, in general, higher diversity values than anthropized sites. Oligarchic species had higher importance in anthropized environments, which also had the most uneven distribution of abundance between species, indicating the dominance by a smaller number of species and the loss of ecological diversity as farmland and urban development increase.Abstract in Spanish is available with online material.

Seasonal movements of small-island birds along habitat and elevation gradients highlights the conservation value of small-scale agroforests

Knowledge on species distributions and seasonal movement patterns within landscapes is important for understanding their ecology and roles in agroecosystems, and is critical for enabling their effective conservation and monitoring, particularly in small-island states where conservation resources are limited. We undertook bird surveys to examine species distributions across a range of agricultural land-use intensities and elevations on the Caribbean island of Grenada by collecting data over 6 repeated monthly surveys (3 wet season, 3 dry season) at sites located in a variety of habitats spread over 6–300 m elevation. We observed a gradual upslope increase in bird species diversity and abundance from the mid-wet season to the late-dry season, as well as a movement from reduced-canopy habitats to closed-canopy habitats in the dry season. The mid-elevation hillsides of Grenada consist of a diverse mosaic of closed canopy secondary forest patches, interspersed among more open agroforests and small-scale cropping and grazed areas. These agroecosystems appear to provide important habitats to birds throughout the year, especially open canopy agroforests in the wet season. We also found that open mixed agroforests contained a greater diversity of fruit, flower, and seed resources than closed canopy habitats such as secondary forest, cacao agroforests, young secondary forests, or dry forest scrub; and that plant food diversity was highest in the wet season. However, bird abundance significantly increased in closed canopy forest habitats during the dry season, suggesting that intact canopy forests provide important dry season habitat for many Grenadian birds, which may be particularly important for species in drier lowland areas experiencing more intensive agricultural land use and urban and resort development. Overall, this research demonstrates the importance of maintaining the functional connectivity of treed habitats at local and landscape scales for species conservation, as well as the contribution of diverse, small-scale agriculture to maintaining small-island bird communities.

Complex and highly saturated soundscapes in restored oak woodlands reflect avian richness and abundance.

Temperate woodlands are biodiverse natural communities threatened by land use change and fire suppression. Excluding historic disturbance regimes of periodic groundfires from woodlands causes degradation, resulting from changes in the plant community and subsequent biodiversity loss. Restoration, through prescribed fire and tree thinning, can reverse biodiversity losses, however, because the diversity of woodland species spans many taxa, efficiently quantifying biodiversity can be challenging. We assessed whether soundscapes in an eastern North American woodland reflect biodiversity changes during restoration measured in a concurrent multitrophic field study. In five restored and five degraded woodland sites in Wisconsin, USA, we sampled vegetation, measured arthropod biomass, conducted bird surveys, and recorded soundscapes for five days of every 15-day period from May to August 2022. We calculated two complementary acoustic indices: Soundscape Saturation, which focuses on all acoustically active species, and Acoustic Complexity Index (ACI), which was developed to study vocalizing birds. We used generalized additive models to predict both indices based on Julian date, time of day, and level of habitat degradation. We found that restored woodlands had higher arthropod biomass, and higher richness and abundance of breeding birds. Additionally, soundscapes in restored sites had higher mean Soundscape Saturation and higher mean ACI. Restored woodland acoustic indices exhibited greater magnitudes of daily and seasonal peaks. We conclude that woodland restoration results in higher soundscape saturation and complexity, due to greater richness and abundance of vocalizing animals. This bioacoustic signature of restoration offers a promising monitoring tool for efficiently documenting differences in woodland biodiversity.

Two listeners detect slightly more birds than a single listener when interpreting acoustic recordings

ABSTRACT Acoustic recorders are increasingly important for monitoring bird populations and have potential to augment existing monitoring programs such as the North American Breeding Bird Survey (BBS). An advantage of acoustic recordings is that they can be reviewed multiple times by multiple experts, potentially yielding improved estimates of species abundance and community richness. Yet, few studies have examined how frequently successive listeners disagree on acoustic interpretations and how strongly estimates of species richness and abundance are altered when multiple experts review each recording. We assigned multiple expert listeners to interpret recordings at 690 BBS stops, and subsequently assigned second listeners to conduct a review of first listeners’ interpretations. We examined the extent to which listeners agreed with each other and quantified the effect of disagreements on resultant estimates of species occurrence, abundance, and stop-level richness. We also compared estimates from acoustic recordings to those obtained during simultaneous field surveys. Estimates were highly correlated for number of species per stop (r = 0.92) and detection probabilities of species (r = 0.97) based on first and second-listener data. Second listeners disagreed with ~9% of first listeners’ interpretations and added an average of ~15% additional species and 16% additional birds not reported by first listeners. Estimates based on acoustic recordings were also highly correlated with those obtained from field surveys, though listeners were unable to count flocks. A single expert reviewer can provide a reasonable approximation of the relative abundance and species composition of birds available for acoustic detection during BBSs. However, acoustic review by multiple listeners may still be important for species that are rare, difficult to identify, or of high conservation concern.

An updated bird checklist for Banke National Park and Buffer Zone, Nepal

A seven-day bird survey Banke National Park and Buffer Zone (BaNPBZ) was carried out in March 2024, followed by a desk study extracting records from eBird and Annual Waterbird counts. These records were used to compile an updated checklist for BaNPBZ. A total of 276 bird species has been recorded up to 6 April 2024 including 23 additional species found in the March 2024 survey and another 16 species located in the desk study. In 2016 BaNPBZ was assessed as an Important Bird and Biodiversity Area (IBA) based largely on the results of two surveys in 2012 and 2016, using globally threatened species and characteristic biome species criteria. Eight globally threatened species have been recorded so far including one species, great slaty woodpecker Mulleripicus pulverulentus which has significant populations in BaNPBZ, so still fulfilling the globally threatened criterion for an IBA. BaNPBZ has extensive forests in the Indo-Malayan tropical dry zone biome. It supports 69 per cent of species characteristic of this biome which have been recorded in Nepal, a larger number than found previously, so strengthening the justification of BaNPBZ as an IBA using the characteristic biome species criterion. Water shortage was identified by park staff as a major threat to wildlife. Access to the national park was limited in the March 2024 survey by the lack of a 4-wheel drive vehicle. However, the buffer zone was much easier to cover and was found to include high-quality tropical broadleaved forest and riverine habitats. Only lower altitudes up to 200 m were covered. Further bird surveys in all seasons, covering all habitats and the full altitudinal range of the park from 153-1247 m should produce many more bird species and are highly recommended.

SEASONAL VARIATION AND ABUNDANCE, RESIDENTIAL AND IUCN STATUS OF AVIAN DIVERSITY IN FOREST COMMUNITY IN JASHPUR DISTRICT (C.G.)

Birds are one of the most important units in the food chain on this planet. They play significant role in the environment. They are good indicators for understanding climate changing in the ecosystems. Birds attract peoples due to their fascinating colors, courtship behavior, sound and their beauty. The present study was carried out in Forest Community in Jashpur District (C.G.) between January to December 2021 with the objectives to explore the bird diversity and seasonal variation along with the factors affecting bird diversity in the study area. Mackinnon’s Listing Method and Point Count Method were used for bird survey during winter and summer seasons. In the present study, attempt has been made to collect the relevant information regarding the avian fauna of around the study site Jashpur (C.G.). The periodic survey of the study area, showed great deal of avian biodiversity. During the study period, a total of 102 bird species during the two year periods belonging to 15 orders and 39 families were reported were recorded. Various bird species recorded during the whole period of study in “Forest area near Sarudih tea garden area (Site A), nearly village Gamharia (Site B) and near Neemgoan dam (Site-C) Jashpur (C.G.).” were given the IUCN status (Table 5.9) so that the conservational measures could be suggested/adopted accordingly. A comparison of the recorded avian species was made with the recent Red Data List published by IUCN. Accordingly, these bird species were categorized into two IUCN categories, namely, Least Concern (LC) and Endangered (EN). According to Red Data Book of IUCN 102, “Globally threatened” species were also recorded from the study area. Out of 100 globally threatened species, and only 2 species was in endangered category.

Mapping the risk of introduction of highly pathogenic avian influenza to Swedish poultry

Outbreaks of highly pathogenic avian influenza (HPAI) have resulted in severe economic impact for national governments and poultry industries globally and in Sweden in recent years. Veterinary authorities can enforce prevention measures, e.g. mandatory indoor housing of poultry, in HPAI high-risk areas. The aim of this study was to conduct a spatiotemporal mapping of the risk of introduction of highly pathogenic avian influenza virus (HPAIV) to Swedish poultry from wild birds, utilising existing data sources. A raster calculation method was used to assess the spatiotemporal risk of introduction of HPAIV to Swedish poultry. The environmental infectious pressure of HPAIV was first calculated in each 5 km by 5 km cell using four risk factors: density of selected species of wild birds, air temperature, presence of agriculture as land cover and presence of HPAI in wild birds based on data from October 2016-September 2021. The relative importance of each risk factor was weighted based on opinion of experts. The estimated environmental infectious pressure was then multiplied with poultry population density to obtain risk values for risk of introduction of HPAIV to poultry. The results showed a large variation in risk both on national and local level. The counties of Skåne and Östergötland particularly stood out regarding environmental infectious pressure, risk of introduction to poultry and detected outbreaks of HPAI. On the other hand, there were counties, identified as having higher risk of introduction to poultry which never experienced any outbreaks. A possible explanation is the variation in poultry production types present in different areas of Sweden. These results indicate that the national and local variation in risk for HPAIV introduction to poultry in Sweden is high, and this would support more targeted compulsory prevention measures than what has previously been employed in Sweden. With the current and evolving HPAI situation in Europe and on the global level, there is a need for continuous updates to the risk map as the virus evolves and circulates in different wild bird species. The study also identified areas of improvement, in relation to data use and data availability, e.g. improvements to poultry registers, inclusion of citizen reported mortality in wild birds, data from standardised wild bird surveys, wild bird migration data as well as results from ongoing risk-factor studies.

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

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

Integrating counts from rigorous surveys and participatory science to better understand spatiotemporal variation in population processes

Abstract Knowledge of variation in population processes (e.g. population growth) across broad spatiotemporal scales is fundamental to population ecology and critical for conservation decision‐making. Count data from rigorous surveys (e.g. surveys with probabilistic sampling design and distance sampling information) can inform population processes but are often limited in space and time. Participatory science data cover broader spatiotemporal extents but are prone to bias due to limited to no sampling design and lack of distance sampling information, hindering their capability of informing population processes. Here, we developed an integrated dynamic N‐mixture model that jointly analyses rigorous survey and participatory science data to inform population growth at broad spatiotemporal extents. The model contains a flexible scaling parameter that allows fixed and random effects to account for biases and errors in participatory science data. We conducted simulations to evaluate the inference performance of this model across a broad range of spatial and temporal overlap between rigorous survey and participatory science data. We also conducted a case study of Baird's Sparrow (Centronyx bairdii), a species of conservation concern, to illustrate the application of the integrated model with rigorous survey data from the Integrated Monitoring in Bird Conservation Regions programme and participatory science North American Breeding Bird Survey and eBird data. Simulations showed that the integrated model improved precision without biasing parameter estimates, in comparison with a model informed by rigorous survey data alone. The case study further demonstrated the utility of the integrated model for quantifying range‐wide, long‐term population processes and environmental drivers despite limited spatiotemporal extent of rigorous survey data. In particular, we found that population growth rate peaked under medium temperature, which were only apparent in the integrated model. The integrated model developed in this study is useful for understanding wildlife population processes at broad spatiotemporal scales with count data. The flexible structure of this model, in particular the scaling parameter, makes it highly adaptable to a broad range of ecological systems and survey procedures. These properties make this modelling approach highly relevant for both population ecology and conservation practice.

Ecological scales of effect vary across space and time

The spatial scale at which an environmental variable is summarized can have considerable impacts on ecological inference of species distribution and abundance. While several analytical approaches have emerged to determine biologically relevant spatial scales – the spatial scale that most strongly influences the ecological patterns observed – identifying key ecological drivers of scale of effect is still underway. Additionally, several predicted ecological drivers of scale of effect can vary across space and time, but little research on spatiotemporal patterns has occurred. Here, I assessed spatial and temporal variation in scales of effect across 32 North American bird species using 18 years of empirical data from the North American breeding bird survey. Scale estimation was then coupled with trait‐based analyses and hypotheses testing of underlying processes of spatial and temporal variation in scales of effect. All 32 species tested exhibited varied scales of effect across years (average annual scales of effect ranging from 0.2 to 4.97 km) and Bird Conservation Regions (BCR), with spatial variability being the most pronounced. Trait‐based analyses revealed a contrary relationship between hand‐wing index, body size, and scale of effect, though the strength of this relationship was contingent on migratory status. Temporal variation in scales of effect was best explained by changes in human development over time, indicating that avian space use can be explained by an increasing human footprint. Additionally, relative population size, consistent with theoretical predictions stemming from density‐dependent population dynamics, explained notable variation in spatial and temporal scales of effect. These findings contribute to the growing landscape ecology literature by providing empirical evidence for hypothesized drivers of scales of effect. By delineating species‐specific scales of effect and elucidating their ecological drivers, this study enhances our understanding of spatial and temporal scales in ecological processes, aiding conservation efforts in a rapidly changing world.

Population Trends of the Ferruginous Hawk (Buteo regalis) Wintering in California

Abstract The Ferruginous Hawk (Buteo regalis) is a raptor of conservation concern in much of its range. Population trend estimates from Breeding Bird Surveys and migration counts for this species are often contradictory and of low credibility. Therefore, we used Christmas Bird Count data to assess population trends for Ferruginous Hawks that winter in California, USA. Evidence suggests that the birds breeding in southeastern Washington and northeastern Oregon may represent a metapopulation that winters almost exclusively in California. Data for the 25-yr period from Count Year 98 (winter 1997–1998) to Count Year 122 (winter 2021–2022) from 22 California Christmas Bird Count circles in the core winter range of Ferruginous Hawks showed a significant positive trend. This positive trend contrasts with the continent-wide negative trends observed for most grassland/open country bird species and is surprising given ongoing declines of this species’ preferred winter habitat in California during this same period. We discuss potential explanations that may account for these differences, including the possibility that the California-wintering Ferruginous Hawks include a large proportion of birds breeding outside of southeastern Washington and northeastern Oregon.

Bird community response to one decade of riparian restoration along the Colorado River delta in Mexico

We assessed the response of breeding birds to one decade of riparian restoration in the Colorado River delta including active vegetation management since 2010 and various environmental water deliveries since 2014. Bird surveys were conducted from 2002 to 2021 at 230 bird count stations distributed along five river reaches with different hydrogeomorphic characteristics, across 7 routes in actively revegetated (“restored”) sites, and 20 routes in non-actively revegetated (“control”) sites. Both restored and control sites could be affected by environmental flows/water deliveries. We examined the temporal trajectories of four community-aggregated metrics for 53 breeding species, and the number of detections (counts) for the 30 most frequently detected among the 53 species at the restored and control sites, using generalized linear mixed-effects models. Diversity and richness of the 53 breeding species were highest in the wettest river reach, but higher than in control sites in only one restored site within one of the driest river reaches. The avian community was recovering in control sites, ameliorating a long-term declining trend, perhaps indicating indirect positive effects of active restoration. The response to restoration of the 30 most common species was species-specific. Ten of the 16 riparian forest specialist species had more detections in restored sites of the wettest reach (vs. only two in the driest reach). Species with preference for agricultural fields and generalists had the highest counts along the entire delta. Generalists generally decreased following revegetation, which was another positive restoration effect. Our results will be used to help guide future restoration efforts.

Orchard management factors affecting rates of bud damage to kiwifruit orchards

Although bird damage to fruit crops is well documented, bird damage to flower and leaf buds is relatively understudied. In Aotearoa/New Zealand, bird damage to kiwifruit (Actinidia deliciosa and Actinidia chinensis) buds has been reported to be widespread. However, the responsible bird species and rates of damage have not been investigated, nor is it known if orchard management such as the presence of shelterbelts, and management of swards (grass) between vines or characteristics of the surrounding landscape affect patterns of bud damage. We aimed to identify the bird species responsible for damage to kiwifruit buds, the extent of damage across orchards, and factors correlated with bud damage. A combination of bird surveys, trail cameras, and bud damage surveys were employed across 18 kiwifruit orchards in the Bay of Plenty, Aotearoa/New Zealand. House sparrows (Passer domesticus), chaffinches (Fringilla coelebs), and silvereyes (Zosterops lateralis) were identified as the most frequent species damaging buds. On average, 10% of buds were damaged, but rates of damage varied widely across orchards. Increasing availability of sward seeds was associated with increasing bird abundance but decreasing bud damage levels, potentially because seeds from sward vegetation offer an alternative food source. Shelterbelt volume, block management type (conventional vs organic), and the proportion of vegetation in the surrounding landscape also influenced bird abundance and damage. Understanding which management and environmental factors influence bird abundance and damage may benefit bird management in orchards, such as leaving swards unmown to increase sward seed availability and to reduce bird damage levels to kiwifruit buds.

Quantifying the effects of landscape and habitat characteristics on structuring bird assemblages in urban habitat patches

Understanding the determinants of biodiversity in fragmented habitats is fundamental for informing sustainable landscape development, especially in urban landscapes that substantially fragment natural habitat. However, the relative roles of landscape and habitat characteristics, as emphasized by two competing frameworks (the island biogeography theory and the habitat diversity hypothesis), in structuring species assemblages in fragmented habitats have not been fully explored. This study investigated bird assemblages at 26 habitat patches (ranging in size from 0.3 to 290.4 ha) in an urban landscape, southwest China, among which habitat type composition and woody plant species composition varied significantly. Through 14 bird surveys conducted over six breeding seasons from 2017 to 2022, we recorded 70 breeding bird species (excluding birds recorded only once and fly-overs, such as raptors, swallows and swifts), with an average of 26 ± 10 (SD) species per patch. We found that patch area had significant direct and indirect effects on bird richness, with the indirect effects mediated by habitat richness (i.e., the number of habitat types). Isolation (measured as the distance to the nearest patch), perimeter to area ratio (PAR), and woody plant richness did not significantly predict variation in bird richness. Furthermore, none of these factors significantly sorted bird species based on their functional traits. However, the overall makeup of bird assemblages was significantly associated with the specific habitat types and woody plant species present in the patches. The results suggest that neither the island biogeography theory nor the habitat diversity hypothesis can fully explain the impacts of habitat fragmentation on bird richness in our study system, with their roles primarily being linked to patch area. The findings that habitat and plant compositions were the major drivers of variation in bird assemblage composition offer valuable insights into urban planning and green initiatives. Conservation efforts should focus not only on preserving large areas, but also on preventing urban monocultures by promoting diverse habitats within those areas, contributing to the persistence of meta-communities.

Which Forest Characteristics Shape Bird Abundance in Central European Forests? A Case Study Based on Common Breeding Bird Survey in Czechia

Which Forest Characteristics Shape Bird Abundance in Central European Forests? A Case Study Based on Common Breeding Bird Survey in Czechia

Range and climate niche shifts in European and North American breedingbirds.

Species respond dynamically to climate change and exhibit time lags. Consequently, species may not occupy their full climatic niche during range shifting. Here, we assessed climate niche tracking during recent range shifts of European and UnitedStates (US) birds. Using data from two European bird atlases and from the North American Breeding Bird Survey betweenthe 1980s and 2010s, we analysed range overlap and climate niche overlap based on kernel density estimation. Phylogenetic multiple regression was used to assess the effect of species morphological, ecological and biogeographic traits on range and niche metrics. European birds shifted their ranges north and north-eastwards, US birds westwards. Range unfilling was lower than expected by null models, and niche expansion was more common than niche unfilling. Also, climate niche tracking was generally lower in US birds and poorly explained by species traits. Overall, our results suggest that dispersal limitations were minor in range shifting birds in Europe and theUSA while delayed extinctions from unfavourable areas seem more important. Regional differences could be related to differences in land use history and monitoring schemes. Comparative analyses of range and niche shifts provide a useful screening approach for identifying the importance of transient dynamics and time-lagged responses to climate change. This article is part of the theme issue 'Ecological novelty and planetary stewardship: biodiversity dynamics in a transforming biosphere'.

Ocurrence dataset of birds in university campuses of Nanjing, Juangsu Province China.

The protection of urban biodiversity plays a critical role in maintaining urban ecological security. As a unique taxon of urban wildlife, birds have been intensively used as an indicator of our surrounding environment. Although the diversity of urban bird species has received increasing attention, present studies are mainly focused on urban parks. As one of the important components of the urban ecosystem, the university campus also plays a critical role in maintaining bird diversity. Due to the lack of observation data, it is a challenge to evaluate the impact of the environmental conditions on campus bird diversity. Given the most concentrated higher education resources in China, Nanjing has a large number of universities, covering a wide area of the urban landscape. The landscape of these universities usually has a high percentage of green space as well as waterbodies, which is conducive to attracting various bird species to inhabit. Here, we conducted a one-year bird survey from January 2019 to December 2019 in 12 universities in Nanjing and provided an occurrence dataset containing detailed species and geographical information, providing a good source to study the ecological and anthropogenic factors on urban bird diversity on a local and larger scale. This dataset represents the first annual record of birds publicly released by 12 universities in Nanjing, Jiangsu Province. It includes classification information, population, distribution and survey details. All data have been published on GBIF.