Toward a Global Classification of Coastal Anthromes

Muscling mussels: Understanding the invasive potential of the South American bivalve Mytella strigata (Hanley, 1843) in the Northern Indian Ocean

In past decades, non-native species invasion has emerged as one of the leading drivers of biodiversity loss in terrestrial and aquatic ecosystems globally. In aquatic ecosystems, invasion by bivalve species has increased substantially due to their evolutionary resilience and adaptability. This study aimed to determine the habitat suitability of the South American bivalve Mytella strigata in the northern Indian Ocean using Species distribution modelling. The species occurrence and environmental data for model building were extracted from GBIF, Bio-ORACLE, The World Bank Data Catalogue and GMED. Pearson's correlation (<0.7) and Variance inflation factor (<10) analyses were used to select the environmental covariates. Individual models were built by combining the native range occurrence data of Mytella strigata with the bioclimatic data under the current climatic setting. Ten individual models were built and ensembled to create the final model using the biomod2 package. The variable importance score and the response curve plot were used to identify the most crucial variable and its influence on the models. Distance to port had the highest influence on predicting the distribution of Mytella strigata. The results indicated that the western coast of India as more susceptible to invasion. Our predictions indicate that the species has the potential to become highly invasive in the region, given the vast habitat suitability and documented introduction and presence of the species in the region. This research generated baseline information on the habitat suitability of M. strigata that will aid in managing and restricting its spread in the region. Considering the substantial impact of the species in other introduced ranges worldwide, immediate action should be initiated for the swift management of M. strigata from the Indian coast.

Response of the bacterial metagenome in port environments to changing environmental conditions

Port environments are highly dynamic and hotspots for marine bioinvasion. This study investigated the bacterial diversity at two geographically distant ports (Mangalore-marine port; and Haldia-riverine port) using next-generation sequencing during southwest monsoon and non-monsoon (Pre-monsoon) seasons. During southwest monsoon, at both marine and riverine ports, operational taxonomic units (OTUs) affiliated to bacteria reported to have hydrocarbon degrading ability were observed. Whereas during pre-monsoon, a significant increase in benthic bacterial OTUs was evident at the marine port, and the riverine port was characterized by oceanic species OTUs. Results suggest that the dynamics of prevalent environmental conditions, driven by seasons, led to emergence of ecologically relevant bacteria, many of which have been observed for the first time in Indian coastal waters. Their presence could be used as indicators of prevailing environmental conditions and nature of anthropogenic influence in port ecosystems. Unravelling functional roles of such ecologically relevant species is a way forward.

Fishery-Based Ecotourism in Developing Countries Can Enhance the Social-Ecological Resilience of Coastal Fishers—A Case Study of Bangladesh

The importance of recreational fishing, in many coastal areas and less developed nations, is increasing rapidly. Connecting fisheries to tourism can create innovative tourism products and provide new income sources. The present study is the first to explore the concept of coastal fishery-based ecotourism (FbE) to enhance the social–ecological resilience of coastal fishing communities in a specific tourist spot in Bangladesh. A combination of primary (quantitative and qualitative) and secondary (literature databases) data sources were used in this study. It applied a social–ecological system (SES) and social–ecological resilience (SER) concept to collect quantitative and qualitative data (120 in-depth individual interviews, four focus group discussions, and strengths, weakness, opportunities, and threats-SWOT analyses) and frame their interpretation. The study found that Bangladesh needs to adopt a firm policy to utilize tourism’s potential in national economic development and societal progress. The findings show the considerable potential of the concept that integrates business, education, and an environmental conservation perspective in Bangladesh, specifically for Saint Martin’s Island: 32% of interviewees expressed that increasing employment opportunities and the Gross Domestic Products (GDP) is the primary potential, whereas 31% said it would attract fishing tourists and 23% believed it would develop the local infrastructure and facilities for fishing and tourism. Similarly, most of the respondents (31%) thought that the lack of awareness and promotional activities is the main limitation preventing this initiative from being well accepted. Moreover, based on the findings, specific measures for strengthening the social–ecological resilience of the coastal fishers via FbE at the local level were suggested, including building communal links, developing community infrastructures, revising prevailing rules and regulations, offering alternative means of generating income for fishers during disaster periods, and more active sharing of responsibility between stakeholders and government for the management of FbE. Finally, with its focus on the prospects and challenges of coastal FbE development on Saint Martin’s Island, this article provides a useful reference point for future discourse on similar social and economic strategies. While this study focuses on Bangladesh’s coastal fishing villages, the results are possibly applicable more broadly in similar contexts and developing countries worldwide.

Defining Coastal Resilience

The concept of resilience has taken root in the discourse of environmental management, especially regarding Building with Nature strategies for embedding natural physical and ecological dynamics into engineered interventions in developed coastal zones. Resilience is seen as a desirable quality, and coastal management policy and practice are increasingly aimed at maximising it. Despite its ubiquity, resilience remains ambiguous and poorly defined in management contexts. What is coastal resilience? And what does it mean in settings where natural environmental dynamics have been supplanted by human-dominated systems? Here, we revisit the complexities of coastal resilience as a concept, a term, and a prospective goal for environmental management. We consider examples of resilience in natural and built coastal environments, and offer a revised, formal definition of coastal resilience with a holistic scope and emphasis on systemic functionality: “Coastal resilience is the capacity of the socioeconomic and natural systems in the coastal environment to cope with disturbances, induced by factors such as sea level rise, extreme events and human impacts, by adapting whilst maintaining their essential functions.” Against a backdrop of climate change impacts, achieving both socioeconomic and natural resilience in coastal environments in the long-term (>50 years) is very costly. Cost trade-offs among management aims and objectives mean that enhancement of socioeconomic resilience typically comes at the expense of natural resilience, and vice versa. We suggest that for practical purposes, optimising resilience might be a more realistic goal of coastal zone management.