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Invasive plants are a growing ecological problem worldwide, but biases and patterns within invasive plant research may affect our understanding of invasive plant ecology. In this study, we analyzed 458 invasive plant papers sampled from the two journals dedicated entirely to the field of invasion biology, i.e., Biological Invasions and Neobiota. From these papers, we collected information on geographic coverage, climate, habitat, taxonomic coverage, plant functional type, and research topic to examine trends across a 21‐year time period from 1999 to 2020. Our analysis found that invasive plant research was consistently biased toward temperate grassland and forest ecosystems particularly within the Americas, Europe, and Australia, and toward smaller, herbaceous invasive plant species (i.e., forbs, grasses, and shrubs), with an increase in interest in invasive nitrogen‐fixing legumes over time. Our analysis also identified "hot" research topics in invasive plant research at specific time periods, such as a peak in the use of genetic analysis methods in 2014–2015 and a more recent focus on plant physiological and functional traits. While current models, concepts, and understanding of plant invasion ecology are still driven by such biases, this has been partially offset by recent increased research in understudied systems, as well as increasing awareness that plant invasion is heavily affected by their growth types, physiological traits, and soil interactions. As the field of invasion biology becomes ever increasingly important over time, focusing invasive plant research on understudied ecosystems and plant groups will allow us to develop a more holistic understanding of the ecology of invasive plants. In particular, given the outsized importance of the tropics to global biodiversity, the threats they face, and the dearth of studies, it is of critical importance that more invasive plant research is conducted within the tropics to develop a more globally representative understanding of invasive plant ecology. [ABSTRACT FROM AUTHOR]

Bird collisions with buildings are responsible for a large number of bird deaths in cities around the world, yet they remain poorly studied outside North America. We conducted one of the first citywide fine‐scale and landscape‐scale analyses of bird–building collisions in Asia and used maximum entropy modeling (as commonly applied to species distribution modeling) in a novel way to assess the drivers of bird–building collisions in the tropical city‐state of Singapore. We combined 7 years of community science observations with publicly available building and remote sensing data. Drivers of bird–building collisions varied among taxa. Some migratory taxa had a higher relative collision risk that was linked to areas with high building densities and high levels of nocturnal blue light pollution. Nonmigratory taxa had a higher collision risk in areas near forest cover. Projecting our results onto official long‐term land‐use plans, we predicted that future increases in bird–building collision risk stemmed from increases in blue light pollution and encroachment of buildings into forested areas and identified 6 potential collision hotspots linked to future developments. Our results suggest that bird–building collision mitigation measures need to account for the different drivers of collision for resident and migratory species and show that combining community science and ecological modeling can be a powerful approach for analyzing bird–building collision data. [ABSTRACT FROM AUTHOR]

Re‐establishing extirpated wildlife—or "rewilding"—is touted as a way to restore biodiversity and ecosystem processes, but we lack real‐world examples of this process, particularly in Southeast Asia. Here, we use a decade of aggregated camera trap data, N‐mixture occupancy models, and input from local wildlife experts to describe the unassisted recolonization of two native large herbivores in Singapore. Sambar deer (Rusa unicolor) escaped from captivity (in private or public zoos) in the 1970s and contemporary camera trap data show they have only colonized nearby forest fragments and their abundance remains low. Wild pigs (Sus scrofa), in contrast, naturally recolonized by swimming from Malaysia in the 1990s and have rapidly expanded their range and abundance across Singapore. While wild pigs have not recolonized all viable green spaces yet, their trajectory indicates they soon will. We also note that a third ungulate, the muntjac deer (Muntiacus muntjak), was captured in camera trapping in 2014 and 2015 but was never recorded afterward despite increased sampling effort, and thus we do not focus on their presumably unsuccessful recolonization. The divergent rewilding trajectories between sambar deer and wild pigs suggest different conservation outcomes and management requirements. Sambar deer may restore lost plant–animal interactions such as herbivory and seed dispersal without requiring significant management. Wild pigs, in contrast, have reached high numbers rapidly and may require active management to avoid hyperabundance and negative ecological impacts in regions, such as Singapore that lack both hunting and large predators. [ABSTRACT FROM AUTHOR]

Abstract Aim In general, the plant communities of oceanic islands suffer more from exotic plant invasions than their continental equivalents. At least part of this difference may be contributed by differences in non-biological factors, such as the antiquity and intensity of human impacts and the absence of internal barriers to dispersal, rather than differences in inherent invasibility. We tested the resistance of species-rich continental rain forests to plant invasion on a small, continental island that has been subject to prolonged and intensive human impact. Location Singapore is a 683-km2 equatorial island <1 km from the Asian mainland and with a population of 4 million people. It has a continental biota but has been subject to human impacts as intense as on any oceanic island. Methods We sampled twenty-nine sites in seven vegetation types, ranging from urban wasteland to fragments of primary lowland rain forest. In each sample plot, all plant species were identified, exotic cover was estimated, and a range of environmental variables measured. Additional qualitative surveys for exotic invasion were made in other forest areas in Singapore. The data were analysed by Spearman's rank correlation coefficient. Results The number of exotic species recorded at a site was unrelated to the number of native species. Across all sites, percentage canopy opening had the highest correlation with the number of exotic species, while soil pH (which largely reflects the incorporation of calcareous construction wastes) had the highest correlation if the mangrove sites were excluded. There were no exotics in mangrove forest and only a tropical American, bird-dispersed shrub, Clidemia hirta (L.) D. Don (Melastomataceae: Koster's Curse), in primary and tall secondary forest patches. The species-poor early stages of woody plant succession on highly degraded soils were also very resistant to exotic plant invasion. Main conclusions Long-isolated rain forest fragments in an... [ABSTRACT FROM AUTHOR]