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Abstract AimTwo important environmental hazards for nocturnally migrating birds are artificial light at night (ALAN) and air pollution, with ambient fine particulate matter (PM_2.5) considered to be especially harmful. Nocturnally migrating birds are attracted to ALAN during seasonal migration, which could increase exposure to PM_2.5. Here, we examine PM_2.5concentrations and PM_2.5trends and the spatial correlation between ALAN and PM_2.5within the geographical ranges of the world’s nocturnally migrating birds. LocationGlobal. Time period1998–2018. Major taxa studiedNocturnally migrating birds. MethodsWe intersected a global database of annual mean PM_2.5concentrations over a 21‐year period (1998–2018) with the geographical ranges (breeding, non‐breeding and regions of passage) of 225 nocturnally migrating bird species in three migration flyways (Americas,n = 143; Africa–Europe,n = 36; and East Asia–Australia,n = 46). For each species, we estimated PM_2.5concentrations and trends and measured the correlation between ALAN and PM_2.5, which we summarized by season and flyway. ResultsCorrelations between ALAN and PM_2.5were significantly positive across all seasons and flyways. The East Asia–Australia flyway had the strongest ALAN–PM_2.5correlations within regions of passage, the highest PM_2.5concentrations across all three seasons and the strongest positive PM_2.5trends on the non‐breeding grounds and within regions of passage. The Americas flyway had the strongest negative air pollution trends on the non‐breeding grounds and within regions of passage. The breeding grounds had similarly negative air pollution trends within the three flyways. Main conclusionsThe combined threats of ALAN and air pollution are greatest and likely to be increasing within the East Asia–Australia flyway and lowest and likely to be decreasing within the Americas and Africa–Europe flyways. Reversing PM_2.5trends in the East Asia–Australia flyway and maintaining negative PM_2.5trends in the Americas and Africa–Europe flyways while reducing ALAN levels would likely be beneficial for the nocturnally migrating bird populations in each region. 

Abstract Urban areas are foci for the introduction of non‐native plant species, and they often act as launching sites for invasions into the wider environment. Although interest in biological invasions in urban areas is growing rapidly, and the extent and complexity of problems associated with invasions in these systems have increased, data on the composition and numbers of non‐native plants in urbanized areas remain scattered and idiosyncratic.We assembled data from multiple sources to create the Global Urban Biological Invasions Compendium (GUBIC) for vascular plants representing 553 urban centres from 61 countries across every continent except Antarctica.The GUBIC repository includes 8140 non‐native plant species from 253 families. The number of urban centres in which these non‐native species occurred had a log‐normal distribution, with 65.2% of non‐native species occurring in fewer than 10 urban centres.Practical implications: The dataset has wider applications for urban ecology, invasion biology, macroecology, conservation, urban planning and sustainability. We hope this dataset will stimulate future research in invasion ecology related to the diversity and distributional patterns of non‐native flora across urban centres worldwide. Further, this information should aid the early detection and risk assessment of potential invasive species, inform policy development and assist in setting management priorities.