RIVER NETWORKS AS ECOLOGICAL HOTSPOTS AND CORRIDORS FOR INVASIVE AND AQUACULTURE SPECIES: LONG-TERM BIOCLIMATIC MODELING IN LATVIA
DOI:
https://doi.org/10.17770/etr2025vol1.8703Keywords:
bioclimatic long-term modeling, ecological hotspots and corridors, invasive and aquaculture species; river networksAbstract
Climate change significantly affects aquatic biodiversity, particularly through the expansion of invasive species, which pose critical threats to native ecosystems and economic sectors such as aquaculture. This study synthesizes research findings on the impact of climate change-driven species distribution, focusing on three alien thermophilic fish species: silver carp Hypophthalmichthys molitrix, bighead carp Aristichthys nobilis, and pumpkinseed Lepomis gibbosus. The range expansion of this species has continued across the Europe. Using a species distribution modelling approach, predictions are made of the geographic range of the fish based on presence records and environmental variables from the Near-global environmental information for freshwater ecosystems database likely to be associated with habitat suitability and important for the possible further expansion of the species. The results show a possible widespread under the current climate situation and prospects for the future expansion of the species under the influence of climate change in Latvian river networks, identifying ecological hotspots and corridors for these invasive and aquaculture species. In the aquaculture sector, climate change influences the viability of farming conditions and fosters the proliferation of invasive species that compete with or prey upon economically valuable fish stocks. Research on ecological and socioeconomic thresholds in Latvian pond aquaculture underscores the need for adaptive management strategies to mitigate climate-related risks. These findings underscore the necessity for targeted conservation policies, improved invasive species management, and climate-adaptive strategies in aquaculture. Proactive measures, including habitat restoration, stricter biosecurity regulations, and public awareness campaigns, are essential to mitigate the adverse effects of climate change on biodiversity and economic sustainability.
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