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Unsustainable wildlife consumption and illegal wildlife trade (IWT) threaten biodiversity worldwide. Although publicly accessible data sets are increasingly used to generate insights into IWT, little is known about their potential bias. We compared three typical and temporally corresponding data sets (4204 court verdicts, 926 seizure news reports, and 219 bird market surveys) on traded birds native to China and evaluated their possible species biases. Specifically, we evaluated bias and completeness of sampling for species richness, phylogeny, conservation status, spatial distribution, and life-history characteristics among the three data sets when determining patterns of illegal trade. Court verdicts contained the largest species richness. In bird market surveys and seizure news reports, phylogenetic clustering was greater than that in court verdicts, where songbird species (i.e., Passeriformes) were detected in higher proportions in market surveys. The seizure news data set contained the highest proportion of species of high conservation priority but the lowest species coverage. Across the country, all data sets consistently reported relatively high species richness in south and southwest regions, but markets revealed a northern geographic bias. The species composition in court verdicts and markets also exhibited distinct geographical patterns. There was significant ecological trait bias when we modeled whether a bird species is traded in the market. Our regression model suggested that species with small body masses, large geographical ranges, and a preference for anthropogenic habitats and those that are not nationally protected were more likely to be traded illegally. The species biases we found emphasize the need to know the constraints of each data set so that they can optimally inform strategies to combat IWT., (© 2024 The Author(s). Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)

Conservation enforcement is a direct strategy to combat illegal wildlife trade in open markets. Yet, its large-scale effectiveness has not been widely assessed due to the lack of extensive market data. Between August 2016 and June 2017, a national coordinated enforcement campaign led by the leading Chinese authority to combat illegal migratory bird trade coincided with the largest-ever pet bird market survey across China by voluntary birdwatchers before and after the enforcement, which served as a unique natural experiment. Across 73 markets from 22 Chinese provinces, the dataset contains 140,723 birds of 346 species from 48 families and recorded a drastic decline in bird abundance traded after enforcement. Notably, species protected under China's Wildlife Protection Law declined significantly, while commercially bred species increased, although responses to enforcement were spatially heterogeneous. Our model showed that the national protection level was the best predictor for the trend of traded species, even after accounting for confounding factors such as regional baseline enforcement pressure and wild native bird populations. However, the widely traded native songbirds were not offered adequate national protection. Future policies should consider the pet bird trade patterns, target key areas of trade, and develop a more systematic market survey design to monitor trade., Competing Interests: Competing interests statement:X.R. is affiliated with the National Forestry and Grassland Administration but he is not directly involved in the planning and implementation of the enforcement action. J.Z. and Q.W. are from the China Birdwatching Association which carried out the market survey, but they are not involved in the analysis of the data.

Birds share lands with humans at a substantial scale and affect crops. Yet, at a global scale, systematic evaluations of human-bird coexistence in croplands are scarce. Here, we compiled and used meta-analysis approaches to synthesize multiple global datasets of ecological and social dimensions to understand this complex coexistence system. Our result shows that birds usually increase woody, but not herbaceous, crop production, implying that crop loss mitigation efforts are critical for a better coexistence. We reveal that many nonlethal technical measures are more effective in reducing crop loss, e.g., using scaring devices and changing sow practices, than other available methods. Besides, we find that stakeholders from low-income countries are more likely to perceive the crop losses caused by birds and are less positive toward birds than those from high-income ones. Based on our evidence, we identified potential regional clusters, particularly in tropical areas, for implementing win-win coexistence strategies. Overall, we provide an evidence-based knowledge flow and solutions for stakeholders to integrate the conservation and management of birds in croplands., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Huang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The extent to which species' traits, behavior and habitat synergistically determine their response to extreme weather events (EWE) remains poorly understood. By quantifying bird and vegetation assemblages before and after the 2008 ice storm in China, combined with interspecific interactions and foraging behaviours, we disentangled whether storm influences avian reassembly directly via functional traits (i.e. behavioral adaptations), or indirectly via habitat variations. We found that overall species richness decreased, with 20 species detected exclusively before the storm, and eight species detected exclusively after. These shifts in bird relative abundance were linked to habitat preferences, dietary guild and flocking behaviours. For instance, forest specialists at higher trophic levels (e.g. understory-insectivores, woodpeckers and kingfishers) were especially vulnerable, whereas open-habitat generalists (e.g. bulbuls) were set to benefit from potential habitat homogenization. Alongside population fluctuations, we found that community reassembly can be rapidly adjusted via foraging plasticity (i.e. increased flocking propensity and reduced perching height). And changes in preferred habitat corresponded to a variation in bird assemblages and traits, as represented by intact canopy cover and high density of large trees. Accurate predictions of community responses to EWE are crucial to understanding ecosystem disturbances, thus linking species-oriented traits to a coherent analytical framework.

Selective logging is one of the most common forms of forest use in the tropics. Although the effects of selective logging on biodiversity have been widely studied, there is little agreement on the relationship between life-history traits and tolerance to logging. In this study, we assessed how species traits and logging practices combine to determine species responses to selective logging, based on over 4000 observations of the responses of nearly 1000 bird species to selective logging across the tropics. Our analysis shows that species traits, such as feeding group and body mass, and logging practices, such as time since logging and logging intensity, interact to influence a species' response to logging. Frugivores and insectivores were most adversely affected by logging and declined further with increasing logging intensity. Nectarivores and granivores responded positively to selective logging for the first two decades, after which their abundances decrease below pre-logging levels. Larger species of omnivores and granivores responded more positively to selective logging than smaller species from either feeding group, whereas this effect of body size was reversed for carnivores, herbivores, frugivores and insectivores. Most importantly, species most negatively impacted by selective logging had not recovered approximately 40 years after logging cessation. We conclude that selective timber harvest has the potential to cause large and long-lasting changes in avian biodiversity. However, our results suggest that the impacts can be mitigated to a certain extent through specific forest management strategies such as lengthening the rotation cycle and implementing reduced impact logging., (© 2015 The Author(s) Published by the Royal Society. All rights reserved.)

Indirect effects of electronic waste (e-waste) have been proposed as a causal factor in the decline of bird populations, but analyses of the severity impacts on community assembly are currently lacking. To explore how population abundance/species diversity are influenced, and which functional traits are important in determining e-waste susceptibility, here we surveyed breeding and overwintering birds with a hierarchically nested sampling design, and used linear mixed models to analyze changes in bird assemblages along an exposure gradient in South China. Total bird abundance and species diversity decreased with e-waste severity (exposed < surrounding < reference), reflecting the decreasing discharge and consequent side effects. Twenty-five breeding species exclusively used natural farmland, and nine species decreased significantly in relative abundance at e-waste polluted sites. A high pairwise similarity between exposed and surrounding sites indicates a diffuse effect of pollutants on the species assembly at local scale. We show that sensitivity to e-waste severity varies substantially across functional guild, with the prevalence of woodland insectivorous and grassland specialists declining, while some open farmland generalists such as arboreal frugivores, and terrestrial granivores were also rare. By contrast, the response of waterbirds, omnivorous and non-breeding visitors seem to be tolerable to a wide range of pollution so far. These findings underscore that improper e-waste dismantling results in a severe decline of bird diversity, and the different bird assemblages on polluted and natural farmlands imply species- and guild-dependent susceptibility with functional traits. Moreover, a better understanding of the impact of e-waste with different pollution levels, combined multiple pollutants, and in a food-web context on bird is required in future.

Competition theory predicts that local communities should consist of species that are more dissimilar than expected by chance. We find a strikingly different pattern in a multicontinent data set (55 presence-absence matrices from 24 locations) on the composition of mixed-species bird flocks, which are important subunits of local bird communities the world over. By using null models and randomization tests followed by meta-analysis, we find the association strengths of species in flocks to be strongly related to similarity in body size and foraging behavior and higher for congeneric compared with noncongeneric species pairs. Given the local spatial scales of our individual analyses, differences in the habitat preferences of species are unlikely to have caused these association patterns; the patterns observed are most likely the outcome of species interactions. Extending group-living and social-information-use theory to a heterospecific context, we discuss potential behavioral mechanisms that lead to positive interactions among similar species in flocks, as well as ways in which competition costs are reduced. Our findings highlight the need to consider positive interactions along with competition when seeking to explain community assembly.

Extinction risk varies across species and space owing to the combined and interactive effects of ecology/life history and geography. For predictive conservation science to be effective, large datasets and integrative models that quantify the relative importance of potential factors and separate rapidly changing from relatively static threat drivers are urgently required. Here, we integrate and map in space the relative and joint effects of key correlates of The International Union for Conservation of Nature-assessed extinction risk for 8700 living birds. Extinction risk varies significantly with species' broad-scale environmental niche, geographical range size, and life-history and ecological traits such as body size, developmental mode, primary diet and foraging height. Even at this broad scale, simple quantifications of past human encroachment across species' ranges emerge as key in predicting extinction risk, supporting the use of land-cover change projections for estimating future threat in an integrative setting. A final joint model explains much of the interspecific variation in extinction risk and provides a remarkably strong prediction of its observed global geography. Our approach unravels the species-level structure underlying geographical gradients in extinction risk and offers a means of disentangling static from changing components of current and future threat. This reconciliation of intrinsic and extrinsic, and of past and future extinction risk factors may offer a critical step towards a more continuous, forward-looking assessment of species' threat status based on geographically explicit environmental change projections, potentially advancing global predictive conservation science.

There are few empirical data, particularly collected simultaneously from multiple sites, on extinctions resulting from human-driven land-use change. Southeast Asia has the highest deforestation rate in the world, but the resulting losses of biological diversity remain poorly documented. Between November 2006 and March 2008, we conducted bird surveys on six landbridge islands in Malaysia and Indonesia. These islands were surveyed previously for birds in the early 1900 s, when they were extensively forested. Our bird inventories of the islands were nearly complete, as indicated by sampling saturation curves and nonparametric true richness estimators. From zero (Pulau Malawali and Pulau Mantanani) to 15 (Pulau Bintan) diurnal resident landbird species were apparently extirpated since the early 1900 s. Adding comparable but published extinction data from Singapore to our regression analyses, we found there were proportionally fewer forest bird extinctions in areas with greater remaining forest cover. Nevertheless, the statistical evidence to support this relationship was weak, owing to our unavoidably small sample size. Bird species that are restricted to the Indomalayan region, lay few eggs, are heavier, and occupy a narrower habitat breadth, were most vulnerable to extinction on Pulau Bintan. This was the only island where sufficient data existed to analyze the correlates of extinction. Forest preservation and restoration are needed on these islands to conserve the remaining forest avifauna. Our study of landbridge islands indicates that deforestation may increasingly threaten Southeast Asian biodiversity., (© 2010 Society for Conservation Biology.)

Understanding how climate change affects the structure and function of communities is critical for gauging its full impact on biodiversity. To date, community-level changes have been poorly documented, owing, in part, to the paucity of long-term datasets. To circumvent this, the use of 'space-for-time' substitution--the forecasting of temporal trends from spatial climatic gradients--has increasingly been adopted, often with little empirical support. Here we examine changes from 1975 to 2001 in three community attributes (species richness, body mass and occupancy) for 404 assemblages of terrestrial winter avifauna in North America containing a total of 227 species. We examine the accuracy of space-for-time substitution and assess causal associations between community attributes and observed changes in annual temperature using a longitudinal study design. Annual temperature and all three community attributes increased over time. The trends for the three community attributes differed significantly from the spatially derived predictions, although richness showed broad congruence. Correlations with trends in temperature were found with richness and body mass. In the face of rapid climate change, applying space-for-time substitution as a predictive tool could be problematic with communities developing patterns not reflected by spatial ecological associations.

Protected areas are critical for the conservation of residual tropical forest biodiversity, yet many of these are being deforested by humans both within and outside of their administrative boundaries. Therefore, it is critical to document the significance of protected areas for conserving tropical biodiversity, particularly in mega-diverse Southeast Asia. We evaluated the importance of protected areas (national parks [NP], nature reserves [NR], and wildlife reserves [WR]) in preserving avifaunal diversity, particularly the endemic and forest species, on the island of Sulawesi. This island has one of the highest numbers of endemic avifauna genera (12) globally and is also experiencing heavy deforestation. Rarefaction analyses and species estimators showed that parks and reserves consistently recorded higher number of forest, endemic, and endemic forest bird species, in addition to larger population densities, than in their surrounding human-modified areas across eight protected areas (Gunung Manembo-nembo WR, Tangkoko-Batu Angus and Dua Saudara NR, Gunung Ambang NR, Bogani Nani Wartabone NP, Gunung Tinombala NR, Gunung Sojol NR, Lore Lindu NP, and Rawa Aopa Watumohai NP). This implies that protecting natural forests must remain as one of the fundamental conservation strategies in Sulawesi. Two small reserves (Gunung Manembo-nembo WR and Tangkoko-Batu Angus and Dua Saudara NR), however, had high number of forest and endemic bird species both within and outside their boundaries, suggesting the importance of buffer areas for augmenting small reserves so as to improve their conservation value. Ordination analyses revealed the differential response of bird species to different environmental factors (e.g., native tree cover), highlighting the significance of forested habitats with dense native vegetation cover for effective conservation of forest dependent and endemic avifauna. In addition, the distinctiveness in bird species composition among protected areas highlights the importance of establishing a reserve network across major altitudinal zones so as to achieve maximum complementarity for the conservation of Sulawesi's unique avifauna.

Long-term (> 50 years) extinction patterns and processes in isolated tropical forest patches are poorly understood. Considering that forest fragments are rapidly becoming the common feature of most tropical landscapes, data on the long-term conservation value of such fragments are urgently needed. We report on avifaunal turnover in a tropical woodlot (Bogor Botanical Gardens; 86 ha; 54% native and 46% introduced plants; mean 83,649 visitors/month) that has been surveyed several times before and after its isolation in 1936. By 2004 the original avifaunal richness of this woodlot declined by 59% (97 to 40 species) and its forest-dependent avifauna declined by 60% (30 to 12 species). Large-bodied birds were particularly prone to extinction before 1987, but following this time none of the species traits we studied could be considered predictive of extinction proneness. All seven forest-dependent bird species that attempted to colonize this woodlot by 1987 perished thereafter. Our results show that area reduction, isolation, intense human use, and perverse management (e.g., understory removal) of this patch have probably negatively affected the long-term sustainability of its forest avifauna.

The wildlife trade is now one of the greatest threats to biodiversity, and birds are among the most commonly traded groups worldwide. The demand for pet birds is especially high in Indonesia, a country with many exploited, imperiled bird species. Finding solutions to the threat that trade poses for birds, and wildlife in general, requires an understanding of its socioeconomic dimensions. We examined consumer demography and preferences of 762 bird owners in Medan, Sumatra, focusing on the differences among owners of birds taken from the wild versus birds bred in captivity. We found that the vast majority of bird owners have at least one wild-caught bird. However, wild-caught bird ownership is not uniformly distributed across Medan; rather, there are distinct hotspots with high proportions of people with wild-caught birds. The main reasons for owning wild-caught birds are lack of access to and the high cost of captive-bred birds, and a perception that captive-bred birds do not sing as well as wild-caught ones. We conclude that captive-breeding programs could reduce the pressure on wild populations, especially if suppliers are able to produce relatively cheap captive-bred birds. However, the perceived poorer song quality of captive-bred individuals might be a problem for the captive breeding of some species, notably the White-rumped Shama, Copsychus malabaricus . Since many owners of this species compete in bird song competitions, establishing competition categories specifically for captive-bred shamas could promote captive-bred bird ownership. Tackling the problem of the wild bird trade in Indonesia and elsewhere will require consideration of both the economic and the social factors that underlie pet ownership. [ABSTRACT FROM AUTHOR]

Extinction risk varies across species and space owing to the combined and interactive effects of ecology/life history and geography. For predictive conservation science to be effective, large datasets and integrative models that quantify the relative importance of potential factors and separate rapidly changing from relatively static threat drivers are urgently required. Here, we integrate and map in space the relative and joint effects of key correlates of The International Union for Conservation of Nature-assessed extinction risk for 8700 living birds. Extinction risk varies significantly with species' broad-scale environmental niche, geographical range size, and life-history and ecological traits such as body size, developmental mode, primary diet and foraging height. Even at this broad scale, simple quantifications of past human encroachment across species' ranges emerge as key in predicting extinction risk, supporting the use of land-cover change projections for estimating future threat in an integrative setting. A final joint model explains much of the interspecific variation in extinction risk and provides a remarkably strong prediction of its observed global geography. Our approach unravels the species-level structure underlying geographical gradients in extinction risk and offers a means of disentangling static from changing components of current and future threat. This reconciliation of intrinsic and extrinsic, and of past and future extinction risk factors may offer a critical step towards a more continuous, forward-looking assessment of species' threat status based on geographically explicit environmental change projections, potentially advancing global predictive conservation science. [ABSTRACT FROM AUTHOR]

Despite their vulnerability to forest disturbances in the Neotropics, the consequences of forest perturbation on mixed species flocks are poorly understood in the threatened Southeast Asian rainforests. We examined the effects of local-scale habitat disturbance on mixed species flocks along an escalating gradient of anthropogenic modification (i.e., forest interior, forest edge, and urban) in a sub-montane tropical rainforest in Peninsular Malaysia that is presently experiencing low intensity development. Mixed species flocks in the forest interior and forest edge habitats (9.3±2.3 and 8.4±2.3, respectively) had significantly higher number of species than those observed in the urban habitat (5.1±1.7). Flock participation was influenced by environmental characteristics (e.g., canopy cover). Flocking species sensitive to habitat disturbance were likely to be from the Families Corvidae, Nectariniidae, and Sylviidae; had narrow to restricted altitudinal ranges; and were exclusively dependent on primary forest and understory microhabitats. We conclude that sub-montane mixed species flocks are affected by even small scale urbanization and that they, particularly with species richness as a parameter, can be used as effective ecological indicators. With the looming development pressure on the sub-montane/montane habitats in Peninsular Malaysia and the Southeast Asian region, urgent conservation actions are needed for the preservation of their biotas. [Copyright &y& Elsevier]