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Aim Location Methods Results Main Conclusions Mountain ecosystems are hotspots of biodiversity due to their high variation in climate and habitats. Yet, above average rates of climate change and enhanced forest disturbance regimes alter local climatic conditions and vegetation structure, which should impact biodiversity. We here investigated the impact of vegetation and elevation as well as their interactions on bird communities to improve our ability to predict climate change effects on bird communities.European Alps, Germany.We studied patterns and drivers of bird communities at 213 plots along gradients in vegetation density and elevation using autonomous sound recorders. Bird species were identified from soundscapes by Convolutional Neural Networks (BirdNET) and taxonomists.Bird diversity and community metrics were moderately to strongly correlated for data based on either identification by BirdNET or taxonomists (Pearson's r = .47–.94), and ecological findings were overall similar for both datasets. Vegetation density 1–2 m and >2 m above ground strongly affected bird diversity and community composition and mediated effects of elevation. Community composition changed with elevation more strongly in habitats with low than high vegetation density >2 m. Species numbers decreased with elevation in habitats with low vegetation density 1–2 m and >2 m above ground, but increased in habitats with high vegetation density. Overall, functional and phylogenetic diversity increased with elevation indicating lower habitat filtering, but patterns were also mediated by vegetation density.Our results indicate that bird communities in the German Alps are determined by strong interactive effects of elevation and vegetation, underlining the importance to consider variation in vegetation in studies of biodiversity patterns along elevational gradients and under climate change. Combining remote sensing data and biodiversity monitoring based on autonomous sampling and AI‐based species identification opens new avenues for bird monitoring and research in remote areas. [ABSTRACT FROM AUTHOR]

Aim: Artificial island habitats such as human‐made wetlands are emerging novel ecosystems. Understanding the drivers of diversity in such artificial systems is essential for balancing the goals of biodiversity conservation and human socio‐economic needs. Location: Telangana state, India. Methods: We surveyed water birds in a network of 57 artificial wetlands and assessed four macroecological biodiversity patterns: spatial betadiversity, temporal betadiversity, species‐abundance distributions (SADs), and the species–area relationship (SAR). We employed a mix of phenomenological and mechanistic models to examine the four macroecological patterns. We hypothesized that the wetland bird communities are primarily structured by immigration–extinction dynamics and thus that spatial and temporal betadiversity would be high, the within‐wetland SADs would exhibit a large number of rare species and a monotonically declining overall shape, and that the SAR across wetlands would be strongly increasing. Results: Spatial and temporal betadiversity were both high and mostly attributable to turnover rather than nestedness. While the pooled SAD exhibited an interior mode, the SAD for individual wetlands was generally log‐series distributed, consistent with a model in which immigration among wetlands is high. The SAR exhibited an increasing trend, with the 'small‐island effect', which reflects constraints on immigration and is often observed for true island archipelagos, being absent. Main Conclusions: We tentatively conclude that bird diversity in this network of artificial wetlands is mainly structured by immigration–extinction dynamics, although we acknowledge that some of the patterns are also consistent with niche dynamics and future research should measure relevant biotic and abiotic variables in these wetlands. We encourage future work in which our rich dataset is used to fit dynamic models that permit more‐detailed quantitative inferences about mechanisms structuring diversity in this novel ecosystem, which can ultimately also inform conservation management. [ABSTRACT FROM AUTHOR]

Aim: Mountain ecosystems harbour significant biodiversity across elevations and seasons. This biodiversity, however, is increasingly under threat from climate change and human land use. While much work has been done to characterize biodiversity in tropical mountains, far less is known about the environmental, seasonal and spatial factors that impact diversity and community structure in subtropical and temperate regions. Location: Mt. Gongga, Sichuan, China: the eastern‐most peak in Asia above 7000‐m elevation and the main peak of the Hengduan Mountains. Method: We examined elevational patterns and ecological variables underlying taxonomic diversity (TD), phylogenetic diversity (PD), functional diversity (FD) and community structure in birds on the eastern slope of Mt. Gongga between 1100‐ and 4400‐m elevation. We assessed biodiversity patterns between species with different elevational range sizes (small‐ vs. large‐ranged species) and between seasons (breeding vs. non‐breeding season). Results: We recorded 230 bird species across seven field surveys. TD, PD and FD showed similar hump‐shaped elevational patterns in both seasons. In the breeding season, TD, PD and FD for small‐ranged species were highly correlated with climatic factors (mean daily temperature, seasonal temperature range) and vegetation factors (enhanced vegetation index), while large‐ranged species were correlated with spatial factors (mid‐domain effect). In the non‐breeding season, TD, PD and FD for all species groupings were positively correlated with climate factors. For small‐ranged species in both seasons, community structure was more overdispersed at low and high elevations, and more clustered at middle elevations. For large‐ranged species, community structure differed between seasons, showing a general trend towards clustering as elevations increase in the breeding season and trends towards overdispersion and/or evenness as elevations increase in the non‐breeding season. Conclusions: We found that different factors shape elevational patterns of diversity for small‐ and large‐ranged species in the breeding season; small‐ranged species are shaped by climate and vegetation structure, while large‐ranged species are shaped by spatial factors. This difference is likely explained by differences in ecological niche breadth (physiological tolerance and/or habitat specialization) between small‐ranged species and large‐ranged species. In the non‐breeding season, however, when climate is seasonally harsher, we found that patterns of diversity for all range‐size groupings were driven by climatic factors. We also found that community structure generally becomes more overdispersed as resource availability decreases and environmental conditions become harsher, like at higher elevations and in the non‐breeding season, suggesting that competition for limited resources is important for shaping communities in seasonal environments. These findings highlight how avian diversity and community structure are dynamic across a local elevational gradient and seasonally, shifting across the annual cycle, which has implications for conservation strategies and land management. [ABSTRACT FROM AUTHOR]

Aim: Shifting cultivation is a widespread land‐use in many tropical countries that also harbours significant levels of biodiversity. Increasing frequency of cultivation cycles and expansion into old‐growth forests have intensified the impacts of shifting cultivation on biodiversity and carbon sequestration. We assessed how bird diversity responds to shifting cultivation and the potential for co‐benefits for both biodiversity and carbon in such landscapes to inform carbon‐based payments for ecosystem service (PES) schemes. Location: Nagaland, Northeast India. Methods: We surveyed above‐ground carbon stocks and bird communities across various stages of a shifting cultivation system and old‐growth forest using composite carbon sampling plots and repeated point counts directly overlaying the carbon plots in both summer and winter. We assessed species diversity using species accumulation and rarefaction curves based on Hill numbers. We fitted a linear mixed‐effect model to assess the relationship between species richness and fallow age. We also examined possible co‐benefits between carbon and biodiversity from fallow regeneration in terms of relative community similarity to old‐growth forest across carbons stocks. Results: Farmland and secondary forests regenerating on fallowed land had similar bird species richness to old‐growth forests in summer and relatively higher species richness in winter. Within regenerating fallows, we did not find any strong evidence that fallow age influenced bird species richness. Bird community resemblance to old‐growth forest increased with secondary forest maturity, correlating also with carbon stocks in summer. However, bird community assemblage did not show a strong association with habitat types and carbon stocks during winter. Main conclusions: This study underscores the important role of traditional non‐intensive shifting cultivation in providing refuges for biodiversity within heterogeneous habitat mosaics. Effectively managing these landscapes is crucial for both biodiversity conservation and carbon sequestration in the subtropics. [ABSTRACT FROM AUTHOR]

Aim: Wildfires increasingly create large high‐severity patches with interior areas far from less disturbed habitats. We evaluated how these trends impact bird communities by investigating the effect of internal distance from lower‐severity areas, high‐severity patch size, and years since fire on avian alpha and beta diversity. Location: Sierra Nevada, California, USA. Methods: Bird occurrence data were collected during 2009–2017 within high‐severity patches of 27 wildfires representing 1–30 years since disturbance. A two‐step multispecies occupancy method was used to account for imperfect detection of 94 species and estimate effects of patch characteristics on community richness and dissimilarity. Results: Community richness decreased with distance from patch edge and with patch size. Richness increased with years since fire, but this pattern was dependent on distance from edge with higher peak richness (23 species) near edges than interiors (18 species). Community dissimilarity was not associated with distance, indicating that large high‐severity patch interiors contain subsets of, rather than complements to, edge communities. Dissimilarity peaked later with increasing patch size. Guild richness of tree and primary cavity nesters was negatively associated with distance and patch size. Richness of ground and shrub nesters was insensitive to distance, while shrub nester richness increased somewhat with patch size. Due to declines among other species, ground and shrub nesters made up a greater percentage of the avian community within the interiors of large high‐severity patches. Main conclusions: As fire activity increases due to accumulating forest fuels and accelerating climate change, high‐severity patches and their resulting early‐seral habitats are becoming more extensive with less edge and more interior area. Such changes are likely to decrease avian diversity locally and shift community composition away from forest‐associated species. Management actions that promote the full range of fire effects but limit high‐severity patch size may best conserve bird diversity within fire‐adapted ecosystems. [ABSTRACT FROM AUTHOR]

Aim: Climate projections for the upcoming decades predict a significant loss of ice mass particularly critical for glaciers in tropical mountains. In the dry landscapes of the southern Andes (from Southern Peru to Chile), this global trend has strong ecological impacts on high‐altitude wetlands that support a unique avifauna for feeding, roosting and nesting. As glacier runoffs are expected to affect the area and the quality of wetland habitats, these changes may potentially affect bird communities. To address this issue, we studied the structural and functional diversity of bird assemblages in glacier‐fed high‐altitude wetlands (>4500 m). Location: Five valleys of the Cordillera Real, Bolivia. Methods: We surveyed bird communities during dry, wet and intermediate seasons in 40 wetlands (total of 27,720 observations of birds and habitats from 540 transects) showing different degrees of dependence on glacial meltwater. We examined the potential effect of glacier retreat on bird communities through changes in wetland area and environmental quality and heterogeneity. Results: We found strong relationship between wetland area and taxonomic and functional diversity, but not on phylogenetic diversity. Generalized additive models revealed that avian diversity was influenced by wetland's productivity and elevation and maximized at intermediate levels of glacier influence. Multivariate analysis further showed that habitat productivity and humidity, both potentially influenced by future glacial retreat trends, are the main drivers of bird community composition, with the wettest habitats being crucial for aquatic birds and uncommon species. Main conclusions: Glacier retreat may significantly affect bird community diversity and composition through changes in both area and quality of high‐altitude wetlands, with a particular concern for aquatic birds. [ABSTRACT FROM AUTHOR]

Aim: We investigated taxonomic and functional beta diversity of bird communities inhabiting Mediterranean olive groves subject to either intensive or low‐intensity management of the ground cover and located in landscapes with different degrees of complexity. Location: Andalusia, southern Spain. Methods: We partitioned taxonomic and functional beta diversity into its two additive components, turnover and nestedness. We also explored the contributions of single sites to overall beta diversity (LCBD) and separated the effects of species replacement (turnover) and richness difference (nestedness) in order to identify ecologically unique sites—keystone communities—within the metacommunity. In a further step, we employed abundance‐ and functional‐based indicator species analyses to characterize bird assemblages. Results: Taxonomic beta diversity increased with landscape complexity. Although both taxonomic and functional differences among assemblages were driven mainly by species replacement (regardless of management or landscape type), the contribution of trait replacement to the total functional beta diversity was much lower, suggesting that species performing similar functions replace each other between sites. There were no differences in LCBD between management types or categories of landscape complexity, but the contributions of sites to beta diversity decreased as the percentage cover of olive groves increased. Species richness was also important in explaining variation in LCBD as species‐poor sites tended to contribute the most to the local‐to‐regional beta diversity. However, some farms displayed high values of LCBD due to the existence of a high replacement component, indicating that some species recorded in these sites were scarce elsewhere. The indicator species analyses revealed that the woodchat shrike Lanius senator may constitute an excellent indicator of biodiversity in this agro‐forestry system. Main conclusions: Our results show that agricultural expansion promotes biotic homogenization and exemplify how the identification of both keystone species and communities can represent a powerful tool for the management of anthropized landscapes. [ABSTRACT FROM AUTHOR]

Aim: The identification of the mechanisms determining spatial variation in biological diversity along elevational gradients is a central objective in ecology and biogeography. Here, we disentangle the direct and indirect effects of abiotic drivers (climatic conditions, and land use) and biotic drivers (vegetation structure and food resources) on functional diversity and composition of bird and bat assemblages along a tropical elevational gradient. Location: Southern slopes of Mt. Kilimanjaro, Tanzania, East Africa. Methods: We counted birds and recorded bat sonotypes on 58 plots distributed in near‐natural and anthropogenically modified habitats from 700 to 4,600 m above sea level. For the recorded taxa, we compiled functional traits related to movement, foraging and body size from museum specimens and databases. Further, we recorded mean annual temperature, precipitation, vegetation complexity as well as the number of fruits, flowers, and insect biomass as measures of resource availability on each study site. Results: Using path analyses, we found similar responses of bird and bat functional diversity to the variation in abiotic and biotic drivers along the elevational gradient. In contrast, the functional composition of both taxa showed distinct responses to abiotic and biotic drivers. For both groups, direct temperature effects were most important, followed by resource availability, precipitation and vegetation complexity. Main Conclusions: Our findings indicate that physiological and metabolic constraints imposed by temperature and resource availability determine the functional diversity of bird and bat assemblages, whereas the composition of individual functional traits is driven by taxon‐specific processes. Our study illustrates that distinct filtering mechanisms can result in similar patterns of functional diversity along broad environmental gradients. Such differences need to be taken into account when it comes to conserving the functional diversity of flying vertebrates on tropical mountains. [ABSTRACT FROM AUTHOR]

Aim: Although land use change is a leading cause of biodiversity loss worldwide, there is scant information on the extent to which it has affected the structure and composition of bird communities in the Afrotropical region. This study aimed to quantify the effects of habitat transformation on taxonomic, functional and phylogenetic diversity in Afrotropical bird communities. Location: Nyungwe landscape, a montane rainforest with adjoining farmland in south‐west Rwanda. Methods: Data on bird occurrence, abundance and functional traits were collected in 2017/18 using point counts. We also collected data on habitat and morphological traits for all bird species recorded. We quantified bird diversity using a range of metrics, including the inverse Simpson index, functional dispersion and the standardized effect size of mean nearest taxon distance. Results: In comparison with primary forest areas, even low levels of land use change altered species composition and reduced species diversity. Although overall functional diversity and phylogenetic diversity were similar across land use types, we found a significant contraction of trophic and locomotory trait structures of bird communities in restored areas and cultivated areas, respectively. Soil moisture, elevation and lower vegetation height were major factors influencing taxonomic, functional and phylogenetic dimensions of bird communities, although their effects varied across these dimensions. Main conclusions: The sensitivity of forest species to minor habitat disturbance emphasizes the value of conserving primary vegetation. Long‐term conservation of bird communities in Afromontane ecosystems requires halting wide‐scale destruction of primary forest, promoting vegetation heterogeneity in the ecological restoration of degraded habitats and adopting wildlife‐friendly agricultural practices. Our results suggest that monitoring and conservation in these landscapes can be refined using taxonomic, functional and phylogenetic diversity metrics to provide complementary information about the current and likely future impacts of land use change. [ABSTRACT FROM AUTHOR]

Aim: We analysed the role of species interactions in wildlife community responses to urbanization. Specifically, we investigated non‐trophic associations within a bird community and the role of trophic interactions in the responses of bird species to the urbanization gradient. Location: City‐state of Berlin, Central Europe. Methods: Arthropod and bird abundances were sampled across the study area and analysed using hierarchical joint species distribution models (JSDMs). Urbanization gradient was defined by environmental predictors reflecting anthropogenic disturbances, for example noise level and human population density, as well as nature‐like features, for example tree cover and open green area. Relevant environmental predictors for each group and relevant spatial resolution were selected a priori using AICc. Arthropod abundances were modelled for the bird sampling transects and included as additional predictor variable in the bird community model. In this model, we used abundances and traits of 66 breeding bird species as response variables. Results: Bird species responses to urbanization were captured by the interaction between invertebrate abundance and environmental predictors. We identified three groups of birds: the urban group (12 species) showed no decrease in abundance along the urbanization gradient and were not related to arthropods abundance; the woodland group (18 species) were positively related to tree cover and arthropod abundance, also in areas with high anthropogenic disturbance; and the nature group (36 species) were positively related to arthropod abundance, but the species abundance decreased sharply with increasing anthropogenic disturbance. All the non‐trophic associations found within the bird community were positive. Main conclusions: Arthropod abundance clearly modulated birds' responses to the urbanization gradient for most species. Especially at moderate levels of anthropogenic disturbance, the abundance of arthropods is key for the occurrence and abundance of bird species in urban areas. To maintain bird diversity in urban green areas, management measures should focus on maintaining and increasing invertebrate abundance. [ABSTRACT FROM AUTHOR]

Aim: The protection of phylogenetic diversity has become a priority in conservation biology, but its achievement requires a detailed understanding of (a) hotspots of phylogenetic diversity on a management‐relevant scale and (b) the land use and climate factors determining local phylogenetic diversity. In this study, we identified spatial patterns of taxonomic and phylogenetic diversity and their environmental drivers. Location: Bavaria, Germany. Methods: To map the cross‐taxon phylogenetic diversity, we combined species distribution data obtained from country‐wide monitoring programmes and phylogenetic trees of birds, bats, dragonflies, grasshoppers and butterflies and calculated the phylogenetic diversity standardized by species richness. Generalized additive models were used to test the effects of land use and climate on phylogenetic diversity. We identified hotspots of phylogenetic diversity and assessed the extent to which established protected areas in Bavaria cover these hotspots. Results: High coverage by urban areas, arable land and water bodies negatively affected the phylogenetic diversity of most species groups. The phylogenetic diversity of birds increased with increasing meadow cover. Climate did not influence the phylogenetic diversity of the studied groups. We identified 10 regional hotspots that contained the highest standardized phylogenetic diversity across the examined species groups. There was a strong mismatch between hotspots of phylogenetic diversity among the species groups. Protected areas (national parks, natural reserves and areas of the Flora‐Fauna‐Habitat Directive) overlapped only to ~9.6% with these hotspots of standardized phylogenetic diversity. Main conclusions: Cross‐taxon approaches are required to identify hotspots of phylogenetic diversity at a management‐relevant scale. At regional scales, land use was more important than climate in determining phylogenetic diversity. Our study highlights the importance of involving land users into strategies for protecting phylogenetic diversity. [ABSTRACT FROM AUTHOR]

Aim: Describing the spatio‐temporal dynamics of biotic communities is critical for understanding how environmental change can affect biodiversity. Mountains are especially susceptible to such changes (e.g., climate change) and, consequently, have been identified as ecosystems of conservation concern. With their sharp physical and ecological transitions, altitudinal gradients allow examining the influence of different climatic conditions and land use types on species assemblages across small spatial extents, and thus, they constitute natural laboratories to study diversity–environment relationships. Location: Switzerland. Methods: We take advantage of long‐term (20 years) monitoring data and an extensive trait dataset (100 traits) to examine spatial patterns, temporal trends, and spatio‐temporal dynamics in functional and beta diversity of bird communities in the Swiss Alps. Results: Functional diversity indices showed a congruent pattern over time and across space; most indices decreased over the study period and were strongly correlated with altitude. In agreement with studies from the tropics, we found that communities in the lowlands were functionally over‐dispersed, whereas communities at higher elevations were functionally clustered. High‐altitude communities exhibited high functional originality, low levels of niche differentiation and a high turnover rate. Beta diversity declined over the study period. Conclusions: Our findings suggest that pastoral abandonment does not result in an increase in avian functional diversity as most species colonizing woody‐encroached grasslands are functionally redundant, whereas alpine meadows are inhabited by species exhibiting a high degree of habitat specialization and unique functional traits. Hence, the tree line constitutes a boundary between two well‐differentiated functional groups: one representing a functional continuum from lowlands dominated by agricultural landscape to high‐mountain forests, and the other one composed of alpine communities. Overall, this study reveals a process of biotic homogenization (i.e., increasing functional similarity) across the last two decades in the Swiss Alps, coinciding with the recently reported increases in the abundance of generalist species. [ABSTRACT FROM AUTHOR]

Aim: Changes in climate and land use are modifying biodiversity worldwide. Yet it remains unclear how both drivers interact to structure communities and determine patterns in taxonomic, phylogenetic and functional diversity at local scales. We focused on bird diversity and asked: how do precipitation and forest cover gradients interactively structure these elements of avian diversity? Location: Guanacaste, North‐western Costa Rica. Methods: We quantified changes in the abundance and composition of bird communities along independent gradients of regional precipitation, local forest cover and landscape forest cover that serve as proxies for climate drying and habitat conversion. We conducted point counts at 150 sites and statistically accounted for imperfect detection to test how environmental variation shaped community‐wide diversity metrics. Results: We found that the three dimensions of diversity diverged in their responses to environmental gradients. Specifically, species richness increased linearly with precipitation, reached maximum values with intermediate tree cover at local scales and peaked at high levels of landscape tree cover. While phylogenetic diversity did not vary strongly across any gradient, functional diversity increased monotonically with both local and landscape‐level tree cover. Maximum values of functional diversity only occurred in large patches of forest where the tree cover was >75% at both local and landscape scales. Contrary to our expectations, we did not detect significant interactions between precipitation and tree cover gradients on any metric of local bird diversity. Main conclusions: Our findings suggest that taxonomic diversity was more sensitive to environmental gradients than functional and phylogenetic diversity. The lack of synergies between precipitation and forest cover gradients on alpha diversity, at least in this system, simplifies the prospects of predicting future biodiversity change at local scales as our results suggest that climate change and land use act independently of one another. [ABSTRACT FROM AUTHOR]

Aim: Despite their often high‐trophic position and their contribution to many ecosystem functions, little is known about the factors affecting assemblage structure of medium‐ and large‐sized neotropical vertebrates. We examined the relative roles played by the physical and biological environment, and by purely spatial processes, in shaping the composition and diversities of these vertebrate assemblages. Then, based on the theory that the Guianan forest cover shrank to isolated pockets during the late Pleistocene–Holocene, we tested if the past forest refugia may have shaped current vertebrate assemblages. Location: French Guiana, Guiana Shield, South America. Methods: Abundances of 19 medium‐ and large‐sized vertebrates were estimated at 21 locations in undisturbed Guianan rain forests. Using taxonomic, functional and phylogenetic metrics, we partitioned the effects of a range of physical and biological environmental conditions and purely spatial predictors in shaping both assemblage composition and (alpha and beta) diversities. Results: We identified a significant, but weak relationship between taxonomic, functional and phylogenetic assemblage composition and environmental conditions. Assemblage diversity patterns were mainly explained by spatial predictors irrespective of the metrics. Current assemblage diversities are correlated with Pleistocene–Holocene forest history, with the highest alpha diversities outside of putative forest refugia, and the highest beta diversities inside these areas. Main conclusions: Current vertebrate assemblage composition is not strongly marked by common environmental factors. Our main conclusion is that assemblage composition results from individual species responses to the environment. Our findings also suggest that dispersal‐related processes or more probably historical processes shape (alpha and beta) diversity patterns. In fact, forest fragmentation during Pleistocene–Holocene climate changes could have led to isolated vertebrate assemblages evolving into unique species assemblages creating the current high beta diversity inside refugia, whereas the lower habitat stability outside of refugia could have led to mixed assemblages in areas recolonized by forest vertebrates (current high alpha diversity outside of refugia). [ABSTRACT FROM AUTHOR]

Aim: To demonstrate that the population of barn swallow Hirundo rustica in South Africa in the austral summer is not a pan‐mixture of birds from their vast Palaearctic breeding range and to estimate proportions of barn swallows in four South African regions migrating to three breeding ground zones. Location: South Africa and Eurasia. Methods: We analysed citizen science barn swallow ringing records, obtained between 1954 and 2011 in South Africa, and their recoveries made in Eurasia. We used the "division coefficient" method to model the spatial variability of the recovery process and to estimate proportions of barn swallows ringed in four regions of South Africa (KwaZulu‐Natal, Gauteng, eastern part of Northern Cape and the Western Cape) migrating to three zones in the Eurasian breeding grounds: western (west of 10°E), central (10°–60°E) and eastern (east of 60°E). Results: The percentages of barn swallows migrating from KwaZulu‐Natal to the eastern and central Palaearctic zones were estimated at 54.0% and 46.0%, respectively. The percentages from Gauteng to the central and western zones were 80.5% and 15.7%, from the Northern Cape to the central and western zones were 43.7% and 56.3% and from the Western Cape to the eastern, central and western zones were 30.8%, 35.4%, 33.8%. The estimate of the observer process suggested that reencounter rates per 10,000 swallows ringed increased from east to west: 32 reencounters per 10,000 in the eastern zone, 36 in the central zone and 50 in the western zone. Main conclusions: These results provide the first quantitative estimates of the composition of barn swallow populations in four regions of South Africa, relative to their Palaearctic breeding zones. [ABSTRACT FROM AUTHOR]

Aim: To test whether native and non-native species have similar diversity-area relationships (species-area relationships [SARs] and phylogenetic diversity-area relationships [PDARs]) and whether they respond similarly to environmental variables. Location: United States. Methods: Using lists of native and non-native species as well as environmental variables for >250 US national parks, we compared SARs and PDARs of native and non-native species to test whether they respond similarly to environmental conditions. We then used multiple regressions involving climate, land cover and anthropogenic variables to further explore underlying predictors of diversity for plants and birds in US national parks. Results: Native and non-native species had different slopes for SARs and PDARs, with significantly higher slopes for native species. Corroborating this pattern, multiple regressions showed that native and non-native diversity of plants and birds responded differently to a greater number of environmental variables than expected by chance. For native species richness, park area and longitude were the most important variables while the number of park visitors, temperature and the percentage of natural area were among the most important ones for non-native species richness. Interestingly, the most important predictor of native and non-native plant phylogenetic diversity, temperature, had positive effects on non-native plants but negative effects on natives. Main conclusions: SARs, PDARs and multiple regressions all suggest that native and non-native plants and birds responded differently to environmental factors that influence their diversity. The agreement between diversity-area relationships and multiple regressions with environmental variables suggests that SARs and PDARs can be both used as quick proxies of overall responses of species to environmental conditions. However, more importantly, our results suggest that global change will have different effects on native and non-native species, making it inappropriate to apply the large body of knowledge on native species to understand patterns of community assembly of non-native species. [ABSTRACT FROM AUTHOR]

Abstract: Aim: It is usually thought that habitat fragmentation acts negatively on species survival, and consequently, on biodiversity. Recent literature challenges whether habitat fragmentation per se affects species richness, beyond the effect of habitat area. Theoretical studies have suggested that fragmentation may matter most when the amount of available habitat is small or at intermediate levels. However, a recent review suggests that the effect of fragmentation on species richness is usually positive. Here, we dissect the richness–fragmentation relationship. What is the effect size? Does it depend upon the amount of habitat cover? How do individual species respond to fragmentation? Methods: Applying a macroecological approach, we empirically related avian richness and the probability of occurrence (pocc) of individual species to fragmentation (number of patches), after controlling for habitat amount in 991 landscapes, each 100‐km2, in southern Ontario, Canada. Results: Species richness was strongly related to total habitat amount, but habitat fragmentation had no detectable additional effect. Individual species’ pocc related strongly to habitat amount. For some species, pocc also related secondarily to habitat fragmentation within landscapes. Logistic models revealed that pocc related significantly negatively to fragmentation after controlling for habitat amount for only ~13% of forest‐ and 18% of open‐habitat species bird species. However, pocc related significantly positively to fragmentation for even greater proportions of species, including some red‐listed species. Fragmentation effects were not stronger at low or intermediate levels of habitat amount within landscapes. Conclusion: In earlier studies, negative effects of isolation were observed at the patch level in experimental manipulations. However, at the landscape level, avian species richness in southern Ontario apparently responds primarily to habitat amount and negligibly to fragmentation. We argue that the evidence is inconsistent with the hypothesis that reducing habitat fragmentation per se would be an effective conservation strategy for birds at the landscape level. [ABSTRACT FROM AUTHOR]

Aim Globally, many bird species nest in tree cavities that are either excavated or formed through decay or damage processes. We assembled an overview of all tree-cavity nesters (excavators and non-excavators) in the world, analysed their geographic distribution and listed the conservation status of all species. Location This is a global analysis of species from every continent except for Antarctica where the lack of trees precludes the occurrence of this group. Methods We reviewed the online version of the Handbook of the Birds of the World Alive, , and primary literature for species known to nest in tree cavities, with tree cavities defined as holes that a bird can enter such that it is not visible from the outside. We classified species by nester type (excavator or non-excavator, and obligate or facultative where possible), conservation threat status and zoogeographic region, and tested for statistical differences in species distributions across realms using chi-square tests. Results At least 1878 species (18.1% of all bird species in the world) nest in tree cavities, of which we considered 355 to be primary excavators, 126 facultative excavators and 1357 non-excavators (we were unable to classify nesting type for 40 species). At least 338 species use cavities created by woodpeckers (Picidae), excluding reuse by woodpeckers themselves. About 13% (249 species) of tree-cavity nesters experience major threats (i.e., status of vulnerable, endangered or critically endangered). The highest richness of tree-cavity nesters is found in the Neotropical (678 species) and Oriental (453) regions, and the highest proportion of threatened species in Australasia (17%). Main conclusion Maintenance of a continual supply of cavities, a process in which woodpeckers and the processes of decay play critical roles, is a global conservation priority as tree cavities provide important nesting sites for many bird species. [ABSTRACT FROM AUTHOR]

Aim Understanding patterns and drivers of variation in abundance across full species ranges is crucial in conservation science, but our knowledge of these forms and processes is limited, especially in the tropics. This study aims to: (1) identify patterns in variation of abundance across sites; (2) examine congruence of abundance hotspots across species and spatial autocorrelation of abundance within species; and (3) assess the nature and strength of environmental correlates of abundance (topography, habitat and human pressure). Location Twenty-six sites across the full ranges of 14 dry forest bird species in northern Peru. Methods Study sites in this patchy habitat were selected within strata derived from species distribution models, while also ensuring geographic representation. Species abundance data from variable-width transects were compared across sites and across range core versus edge; relationships between abundance and environmental variables were examined using GAMs, and spatial autocorrelation was examined with multivariate Mantel tests. Results Although most species were recorded at most sites, local abundance varied by one or two orders of magnitude. Several species showed a humped rather than the classic skewed abundance distribution, with abundance not necessarily highest at the centre of species' ranges. Spatial autocorrelation in species' local abundance was evident only at distances less than 55 km. Sites of maximum abundance for individual species did not coincide-nine different sites held highest densities of at least one species. Relationships between local abundance and almost all environmental correlates were non-linear. Main conclusions The extreme variation in species abundances and the complexity in their relationships with environmental variables have important implications, both for design of conservation-motivated surveys for which we offer some recommendations, and for the need for multiple reserves to capture high local abundances of key species. [ABSTRACT FROM AUTHOR]

Aim Tree plantations can have beneficial or detrimental effects on regional biodiversity. Here, we focus on how the contribution of pine plantations to the maintenance of regional bird diversity varies geographically compared to natural pine forests, after controlling for the effects of other factors that are known to influence the regional richness of pine forest dwelling birds. Location Spain. Methods We combined large-scale datasets from diverse sources (i.e. the Spanish Breeding Bird Atlas, the Third Spanish Forest Inventory, land use and forest distribution maps) to analyse the geographical variation of the contribution of pine plantations in relation to their natural counterparts to the maintenance of the regional species richness of pine forest dwelling birds. To do so, we also controlled for the main environmental, land use and forest structure factors using GLM models. Results Differences in bird diversity among planted and natural pine forests varied along latitudinal and longitudinal gradients after accounting for altitude, climate, land uses and vegetation structure of pine forests. Planted pine forests in the north-west of the Iberian Peninsula have the lowest bird species richness as compared to natural pine forests, and that difference decreased following a north-west-south-east gradient. Differences also varied among pine species; they were larger for the species with a higher productive vocation ( Pinus sylvestris, Pinus nigra and Pinus pinaster) and not significantly different from zero for species with low commercial interest and mainly used for the restoration of tree cover (i.e. Pinus halepensis). Main conclusions The potential of plantations or natural pine forests to enhance biodiversity is highly dependent on both the pine species and the geographical location. On this basis, we identify the geographical areas (and pine species) where a major naturalization effort of plantations would be needed to increase bird diversity. [ABSTRACT FROM AUTHOR]

Aims To investigate how habitat change and different levels of protection interact to determine variation in the (alpha and beta) diversity of bird communities in three bioclimatic zones, considering the impacts of non-native species, and the contribution of these effects to global (gamma) diversity. Location Sierra Gorda Biosphere Reserve, central Mexico. Methods We carried out bird surveys in a number of locations which varied according to their underlying vegetation type, their level of protection and the degree to which they had undergone modification by humans. We conducted a range of analyses to determine the impacts of protection and modification on the richness and mean global population trends of the species found in each location. We compared community composition to assess the homogenization effect of habitat modification. Results Human-modified environments in each of three bioclimatic zones held significantly greater numbers of species (alpha diversity) than unmodified habitats. Human-mediated changes to local bird communities altered patterns of beta diversity in opposite directions; communities across bioclimatic zones were more similar to one another in modified areas than in unmodified areas but, on a local scale, modification of vegetation increased community dissimilarity. The changes are likely to contribute to a decline in global (gamma) diversity, given that globally vulnerable (declining) birds were mostly associated with unmodified, strictly protected areas. Main conclusions We highlight that assessment of human impacts and conservation need depends on the metric of biodiversity used and scale considered: small-scale habitat change increased local and regional avian diversity but strictly protected areas are still required to protect globally vulnerable species. [ABSTRACT FROM AUTHOR]

Aim Cultural landscapes and their biodiversity are threatened by land use changes and the abandonment of traditional farming techniques. Conceptualizing cultural landscapes as social-ecological systems can be useful to develop strategies for biodiversity conservation. First, this study aimed to develop a typology of social-ecological units based on land use patterns. Second, we sought to relate this typology to biophysical and socio-demographic drivers as well as to biodiversity outcomes. Location Southern Transylvania (Romania). Methods We developed a typology of villages in Southern Transylvania based on land use data. We collected species richness data for plants, butterflies and birds, modelled local richness data for each village and related these values to the village typology. Also, we related village typology to biophysical and socio-demographic variables. Results We identified four types of villages that showed distinct species richness patterns. Bird richness was highest in forest-dominated and mixed-land use villages; plant richness was highest in pasture-dominated villages; and butterfly richness was high in arable-dominated, mixed-land use and pasture-dominated villages. The four types of villages had distinct topographic characteristics and also differed in terms of ethnic composition, migration patterns and geographic location. Drawing on a combined understanding of social-ecological variables, different conservation actions could be prioritized for each of the four village types. Main conclusions Applying social-ecological approaches has the potential to inform biodiversity conservation in cultural landscapes. Social-ecological typologies can improve our understanding of complex systems and provide useful input for the development of effective strategies for biodiversity conservation. [ABSTRACT FROM AUTHOR]

Aim In managed forest landscapes, the tolerance of species to contemporary alteration of forest cover is often assumed to reflect their resilience to natural disturbances. We tested this central tenet of ecosystem-based management by comparing the structure of forest bird assemblages among four regions with contrasting historical natural disturbance regimes. Location Canada's boreal and northern hardwood forests. Methods Using point count data from four study regions across Canada, we first determined the relative sensitivity of individual bird species to the contemporary reduction of old forest cover at stand and 'landscape-context' (1-km radius) scales with log-linear models. The richness of species most sensitive to loss of old forest (hereafter 'sensitive species') was then modelled as a function of landscape-scale changes in old forest cover. Differences in the rate of decline in the richness of sensitive species with contemporary cover of old forest were compared among regions using ANCOVA. We then compared broken-stick regression models with linear models to detect thresholds, if present, in this relationship in each region. Results Bird assemblages from regions with relatively infrequent natural disturbances hosted more species sensitive to contemporary reduction in old forest cover. Those species were also more abundant than in regions with frequent natural disturbances, and the rate of decline in their richness with the loss of old forest was steeper in regions with infrequent natural disturbances than in those where they were frequent. However, we did not detect thresholds in this rate of decline in any study region. Main conclusions Our findings are consistent with the contention that historical natural disturbance regimes shape the response of biota to contemporary landscape alterations through evolutionary adaptation. We argue that forest management conducted within the natural range of variability in stand and landscape structure specific to a region is likely to be ecologically sustainable. [ABSTRACT FROM AUTHOR]

Aim Avian communities in human-modified landscapes exhibit varying patterns of local colonization and extinction rates, determinants of species occurrence. Our objective was to model these processes to identify habitat features that might enable movements and account for occupancy patterns in habitat matrices between the Guanica and Susua forest reserves. This knowledge is central to conservation design, particularly in ever changing insular landscapes. Location South-western Puerto Rico. Methods We used a multiseason occupancy modelling approach to quantify seasonal estimates of occupancy, and colonization and extinction rates of seven resident avian species surveyed over five seasons from January 2010 to June 2011. We modelled parameters by matrix type, expressions of survey station isolation, quality, amount of forest cover and context (embedded in forest patch). Results Seasonal occupancy remained stable throughout the study for all species, consistent with seasonally constant colonization and extinction probabilities. Occupancy was mediated by matrix type, higher in reserves and forested matrix than in the urban and agricultural matrices. This pattern is in accord with the forest affinities of all but an open-habitat specialist. Puerto Rican Spindalis ( Spindalis portoricensis) exhibited high occupancy in the urban matrix, highlighting the adaptability of some insular species to novel environments. Highest colonization rates occurred when perching structures were at ≤ 500 m. Survey stations with at least three fruiting tree species and 61% forest cover exhibited lowest seasonal extinction rates. Main conclusions Our work identified habitat features that influenced seasonal probabilities of colonization and extinction in a human-modified landscape. Conservation design decisions are better informed with increased knowledge about interpatch distances to improve matrix permeability, and habitat features that increase persistence or continued use of habitat stepping stones. A focus on dynamic processes is valuable because conservation actions directly influence colonization and extinction rates, and thus, a quantitative means to gauge their benefit. [ABSTRACT FROM AUTHOR]

Aim Global environmental changes challenge traditional conservation approaches based on the selection of static protected areas due to their limited ability to deal with the dynamic nature of driving forces relevant to biodiversity. The Natura 2000 network (N2000) constitutes a major milestone in biodiversity conservation in Europe, but the degree to which this static network will be able to reach its long-term conservation objectives raises concern. We assessed the changes in the effectiveness of N2000 in a Mediterranean ecosystem between 2000 and 2050 under different combinations of climate and land cover change scenarios. Location Catalonia, Spain. Methods Potential distribution changes of several terrestrial bird species of conservation interest included in the European Union's Birds Directive were predicted within an ensemble-forecasting framework that hierarchically integrated climate change and land cover change scenarios. Land cover changes were simulated using a spatially explicit fire-succession model that integrates fire management strategies and vegetation encroachment after the abandonment of cultivated areas as the main drivers of landscape dynamics in Mediterranean ecosystems. Results Our results suggest that the amount of suitable habitats for the target species will strongly decrease both inside and outside N2000. However, the effectiveness of N2000 is expected to increase in the next decades because the amount of suitable habitats is predicted to decrease less inside than outside this network. Main conclusions Such predictions shed light on the key role that the current N2000 may play in the near future and emphasize the need for an integrative conservation perspective wherein agricultural, forest and fire management policies should be considered to effectively preserve key habitats for threatened birds in fire-prone, highly dynamic Mediterranean ecosystems. Results also show the importance of considering landscape dynamics and the synergies between different driving forces when assessing the long-term effectiveness of protected areas for biodiversity conservation. [ABSTRACT FROM AUTHOR]

Aim We explored whether one native bird (the yellow-throated miner Manorina flavigula) greatly affected the composition of avifaunas in > 500,000 km2 in northern Australia. Location Rangelands of north-eastern Australia Methods Repeated avian surveys were conducted in 368 locations, for which in-site vegetation and landscape-contextual measurements were made. Hierarchical Bayesian models were used to determine whether avian assemblages were affected by variation in abundances of the yellow-throated miner. Results Variation in the abundances of the yellow-throated miner appeared to be governed largely by vegetation cover in surrounding landscapes. Summed abundances and richness of birds less massive than the yellow-throated miner (< 53 g) were negatively associated with abundances of the yellow-throated miner. Variation in other widely distributed species with larger body masses than the yellow-throated miner (> 53 g) bird could not explain the patterns of variation in small-bodied species as well as the yellow-throated miner. There were no relationships between abundances and richness of larger species and abundances of the yellow-throated miner. Main conclusions The genus Manorina appears to be a competitive despot insofar as species smaller than it are concerned. There now is strong evidence that the local composition of avifaunas over much of a continent is controlled by the indiscriminate aggression of a colonial genus. Many of the existing ideas in community ecology that have been proffered for explaining the composition of vertebrate assemblages are inadequate for these assemblages given the profound influence of species of the genus Manorina. The mooted agricultural expansion of development in northern Australia almost certainly would favour the spread of the yellow-throated miner and probably will depress the occurrence and abundances of small-bodied bird species. [ABSTRACT FROM AUTHOR]

Aim To quantify bird responses to a large unplanned fire, taking into consideration landscape-level fire severity and extent, pre-fire site detection frequency and environmental gradients. Location South-eastern Australia. Methods A major wildfire in 2009 coincided with a long-term study of birds and provided a rare opportunity to quantify bird responses to wildfire. Using hierarchical Bayesian analysis, we modelled bird species richness and the detection frequency of individual species in response to a suite of explanatory variables, including (1) landscape-level fire severity and extent (2) pre-fire detection frequency, (3) site-level vegetation density and (4) environmental variables (e.g. elevation and topography). Results Landscape-level fire severity had strong effects on bird species richness and the detection frequency of the majority of bird species. These effects varied markedly between species; most responded negatively to amount of severely burned forest in the landscape, one negatively to the amount of moderately burned forest and one responded negatively to the total area of burned forest. Only one species - the Flame Robin - responded positively to the amount of burned forest. Relationships with landscape-scale fire extent changed over time for one species - the Brown Thornbill - with initially depressed rates of detection recovering after just 2 years. The majority of species were significantly more likely to be detected in burned areas if they have been recorded there prior to the fire. Main conclusions Birds responded strongly to the severity and spatial extent of fire. They also exhibited strong site fidelity even after severe wildfire which causes profound changes in vegetation cover - a response likely influenced by environmental features such as elevation and topography. [ABSTRACT FROM AUTHOR]

Aim The brown-headed cowbird is an obligate brood parasite known to exploit a large number of host species and use a variety of habitats. Much attention has been directed towards uncovering the fundamental factors that affect cowbird abundance; however, no study has evaluated these factors in the context of a biogeographic-scale analysis that takes into account spatial autocorrelation. Our primary objective was to compare the relative influence of geography, land cover and host species on the local abundance of cowbirds. Location Great Plains region of the USA. Methods We used data from the North American Breeding Bird Survey and the National Land Cover Database to examine the relationships between cowbird abundance and host species, land cover composition and geographic location of a survey route. Multiple regression models were developed for various combinations of these factors. To control for spatial autocorrelation, we used SAM 4.0 ( Spatial Analysis in Macroecology) software to implement simultaneous autoregressive modelling of the error term. We then used a model comparison approach to identify the factors that most influence cowbird abundance. Results Among all models examined, host species richness was the single most strong predictor and the sole statistically significant predictor. Cowbird abundance increased with host species richness but did not change in any significant way with non-host passerine richness or abundance of host species. Models with land cover variables tended to have the poorest fit to the cowbird abundance data. Main conclusions Our results suggest that cowbirds may be attracted to areas with greater host richness and/or recruit better in such areas, although our data did not allow direct examination of either process. In a greater context, our study demonstrates the utility of a spatially based and geographically extensive analysis in finding range-wide factors that affect the local abundance of a species. [ABSTRACT FROM AUTHOR]

Aim The role of bird-insect interactions in shaping bird distribution patterns at the landscape scale has been seldom investigated. In mosaic landscapes, bird functional diversity is considered to be an important driver of avian insectivory, but depends on forest fragmentation and edge effects from adjacent, non-forest habitats. In a transcontinental experiment, we investigated edge and landscape effects on bird functional diversity and insectivory in mosaic landscapes of mixed forests and open habitats. Location New Zealand and France. Methods We paired edge and interior plots in native forest fragments in New Zealand and native plantation forests in France. We sampled bird communities using point-counts and linear transects respectively and simultaneously quantified avian insectivory as the rate of bird attacks on plasticine models mimicking tree-feeding Lepidoptera larvae. The same seven life traits and attributes were compiled for French and New Zealand birds, including biogeographic origin, body mass, mobility, foraging method, adult diet, nest location and clutch size. Bird functional diversity was quantified on this multitrait basis by four indices: functional richness, evenness, divergence and dispersion. We used mixed models to test for the effects of forest edges, study area, surrounding landscape diversity and native forest cover on bird functional diversity and insectivory. Results We found higher bird functional richness at forest edges than interiors in New Zealand and lower functional richness at edges in France. However, bird functional evenness and divergence were significantly higher at forest edges in the two countries. Functional evenness and dispersion both increased with landscape diversity and evenness increased with native forest cover. Moreover, bird insectivory increased at forest edges with functional evenness, irrespective of the study area. Main conclusions We suggest that intermediate levels of forest fragmentation and edge effects increase avian insectivory in mosaic landscapes, through enhanced functional evenness and trait complementation within predatory bird assemblages. [ABSTRACT FROM AUTHOR]

Aim Anthropogenic land-use change is a major driver of the current extinction crisis, but the processes through which it acts on biodiversity are complex and still poorly understood. Here, we use several biodiversity metrics to make a comprehensive assessment of the response of an endemic-rich bird assemblage to land-use change. Location São Tomé Island (São Tomé and Príncipe, Africa). Methods We sampled bird assemblages in 220 point counts, stratified across three regions and four land-use types. Species richness was examined using accumulation curves and generalized linear mixed-effect models. Compositional and structural changes were analysed with ordination techniques. We used correlations and model selection to identify species traits and environmental variables associated with such changes. Results At the point level, there was a slight decrease of species richness in more intensive land uses. However, higher dissimilarities within these land uses led them to have higher overall species richness. Endemics dominated forest environments and, although most preferred less-disturbed land uses, many persisted across all land uses. Non-endemics were virtually absent from forests, but became very abundant in the more intensive land uses. Canopy cover was the best predictor of the shift between endemic and non-endemic species, and allowed identifying regional differences in the local responses of bird assemblages to land-use change. Main conclusions To better understand biodiversity, it is crucial to use several metrics simultaneously. In São Tomé, simply using species richness, the single most used biodiversity metric, could have been misleading as it concealed major shifts in the bird assemblage structure towards an endemism impoverished avifauna. Despite scarce data on land-use cover, we demonstrate how landscape context can be vital to understand biodiversity patterns and that highly forested surroundings might overestimate the strict value of more intensive land uses. Our results raise concerns about the long-term persistence of endemic species restricted to islands where forested land uses are being lost. [ABSTRACT FROM AUTHOR]

Aim Fire is a major driver of ecosystem structure and process, and shifts in fire regimes are implicated in the decline of many species. Shifting fire regimes have been documented around the world, and fire frequency and extent is predicted to increase in many areas because of changes in both climate and land management. Here, we evaluate how predicted increases in fire frequency are likely to impact on species distributions. Location The tropical savannas of northern Australia. Methods We developed distribution models for 44 bird species using the modelling algorithm Maxent. Our models incorporated bird locality records and environmental variables including climate, total fire frequency and the subset of fire frequency occurring late in the dry season. We investigated the effect of increasing total fire frequency and increasing fire late in the dry season, on species distributions by projecting species model algorithms onto scenarios of incrementally increased total fire frequency. Results The probability of presence for most species was higher when fire frequency late in the dry season was low. Species showed a mixed response to an overall increase in total fire frequency, with one-third predicted to increase in distribution. However, almost all species (98%) showed a decrease in predicted range with increased late-dry season fire, and species distribution area was generally negatively correlated with an increase in late-dry season fire. Main conclusions Our study highlighted the array of responses of species to increasing fire frequency and suggested that increased fire frequency late in the dry season is detrimental to most savanna-restricted bird species. The understanding of individual species' preferences for particular fire frequencies is important for informed conservation planning. [ABSTRACT FROM AUTHOR]