Influence of mature epibenthic fouling communities on colonisation patterns in new offshore wind farms

Arjun Trikannad

The EU's directive to increase renewable energy production has led to significant offshore wind farm development in Belgium, with targets to achieve a 17.5% renewable energy share by 2030. This study examines the succession of subtidal macro-epibenthic fouling communities on artificial substrates introduced by these wind farms in the Belgian part of the North Sea. Focusing on three wind farms—Belwind, Northwester 2, and Mermaid—the research compares community structures from 2012 and 2023 to determine if mature communities on existing structures accelerate the maturation of new ones.

Results show higher species richness and diversity indices in newer wind farms compared to older ones. Invasive species like Crepidula fornicata were notably more prevalent in 2023, suggesting artificial substrates may facilitate the spread of non-native species. Univariate and multivariate analyses, including NMDS and ANOSIM, indicated significant differences in community structures, particularly in spring samples. Despite limitations such as small sample size and exclusion of colonial species, the study highlights the need for long-term monitoring to fully understand the ecological impacts of artificial substrates in marine environments.

Future research should expand datasets, incorporate multiple years, and include both solitary and colonial species to enhance our understanding of these dynamic marine communities.