The Anthropocene is characterised by a continuous human‐mediated reshuffling of the distributions of species globally. Both intentional and unintentional introductions have resulted in numerous species being translocated beyond their native ranges, often leading to their establishment and subsequent spread – a process referred to as biological invasion. Biological invasions are associated with profound changes in the composition, structure, and functioning of recipient ecosystems, plus substantial financial losses and disruptions to society, culture, and human well‐being. These ecological, economic, and socio‐cultural impacts are interrelated, ubiquitous, and detrimental, yet they are often subjectively perceived or inaccurately quantified. Persistent knowledge gaps remain, however, which limit our understanding of the complex and multifaceted causes and mechanisms of invasion impacts. To overcome these gaps and comprehensively capture all related facets pertaining to the nature and diversity of invasion impact, this scoping review of academic studies, grey literature, and expert reports provides a conceptual model for interpreting invasion impacts, structured around three interrelated pillars: impact domains, challenges in the study of impacts, and available risk‐ and impact assessments. We initially explore the various mechanisms and consequences of ecological, economic, and socio‐cultural invasion impacts and their temporal dynamics, substantiating these with relevant empirical examples. We then review common challenges and fallacies in studying invasion impacts, including context specificity and inter‐comparability of impact magnitudes, challenges associated with quantifying non‐ecological impacts, and research biases, before synthesising how risks are analysed and impacts assessed, and how these assessments ultimately inform management decisions. Our review underscores the multifaceted and complex nature of invasion impacts, and that effectively addressing biological invasions requires more than isolated, reactive interventions; it calls for globally coordinated, proactive action underpinned by reliable scientific knowledge, sincere political commitment, and broad public engagement. Drawing on nearly a century of literature and global expert contributions, this work offers a comprehensive, nuanced, and timely overview of the potential consequences of biological invasions, providing a valuable foundation for informing future research directions, management interventions, and policy development.

Litter in the marine environment, in particular plastic, is a significant threat to marine megafauna. Cetaceans are known to ingest or become entangled in marine debris, likely impacting individuals and populations. Southeast Asia is a biodiversity hotspot and harbours a diverse cetacean assemblage. However, there are key knowledge gaps relating to the impact of litter in this region due the lack of experts to survey its vast coastlines. This study aims to address such gaps by using social media, gathering data from Facebook posts relating to cetacean strandings and litter across Southeast Asia between 2009 and 2019. Results show that at least 15 cetacean species have been negatively affected by litter, with ingestion most commonly affecting deep-diving species. Epipelagic and mesopelagic foragers were most vulnerable to entanglement. Davao in the Philippines was identified as a litter-related stranding hotspot. The Irrawaddy dolphin (Orcaella brevirostris) and pygmy sperm whale (Kogia breviceps) are particularly vulnerable to litter. The combination of social media and peer reviewed literature can help build a more complete picture of the spatial distribution of marine litter and the scale of the impact it has on cetacean populations. In this study we provide details of a valuable online tool for helping to understand the impact of marine litter on cetaceans and other charismatic species that are a focus of community engagement.

Marine biodiversity plays a vital role in ecosystem resilience and stability against climate change and alien species invasions, among others. This also plays a role in the provision of ecosystem services and functions that benefits humans. However due to anthropogenic activities and population increase, marine biodiversity have been affected most. We conducted a review using open-sourced journals on the effects of nutrient enrichment, sedimentation, heavy metals and plastic pollution in the marine environment and its implications on marine biodiversity. Lethal and sub-lethal effects were observed in different organisms that could affect marine biodiversity directly or indirectly. Direct effects include mortality of organisms while indirect effects include habitat degradation or alteration, a simplified food web, increase alien species invasion and reduced fitness of organisms. Human land use change, coastal construction activities, untreated sewage discharges, pesticides, mine tailings, uncollected, unsegregated and improperly dumped garbages and unabated garbage dumping at sea have been found to negatively influence marine biodiversity. In the Philippines, very few studies have been conducted with regards to marine pollution, especially on marine plastic debris, and even fewer studies have been made that tackles the effect of these stressors at an ecosystem level. Furthermore, this review has identified direct and indirect effects of pollution stressors on marine organisms which include: mortality and reduced fitness, vulnerability to disease or sickness,-habitat degradation, and food web simplification. Keywords - Ecology, nutrient enrichment, sedimentation, plastic, biodiversity, literature review, pollution, Philippines

Non-native species introductions threaten global biodiversity, ecosystems, and the services they provide. The limited capacity of developing countries to mitigate and manage biological invasions increases their vulnerability to the resulting impacts. Developing countries’ lack of comprehensive information on non-native species to help formulate sound management efforts is a key challenge. Here, we provide the most comprehensive national list of established non-native species in the Philippines, along with an update on the Southeast Asian region to aid national and regional efforts in addressing the threats posed by biological invasions. Our assessment indicates that the Philippines currently hosts at least 1,029 established non-native species, the highest number among Southeast Asian countries, amidst a total of 2,528 non-native species established in the region. A taxonomic breakdown showed species of the division Tracheophyta and phylum Chordata to be the majority of established non-native species in the Philippines, most of which are found in terrestrial ecosystems. A network analysis further highlighted a high degree of similarity in the composition of established non-native species among Southeast Asian countries, with the Philippines’ non-native species community most closely resembling that of Indonesia, likely due to close socio-economic ties and similar climatic niches and environmental conditions. Finally, we identified 1,499 non-native species established in Southeast Asia but not the Philippines, which may pose potential future threats for the country. We highlight the need for more comprehensive research on established non-native species in the Philippines and the Southeast Asian region, particularly taxonomic studies and research at broader geographic scales, to better understand the distribution and impact of these species and stress the critical need to address this transboundary threat.