Shipwrecks function as ecologically significant artificial reef habitats that can support diverse reef fish assemblages in marine environments. Given their abundance and dispersed distribution across coastal waters, understanding the factors that influence reef fish movement and connectivity among these structures is essential for effective conservation and spatial management. However, the extent to which geographic distance constrains fish dispersal between shipwrecks remains poorly understood, particularly in data-limited regions. This knowledge gap limits current understanding of how shipwrecks contribute to broader ecological networks in tropical marine systems.
This study investigated the relationship between geographic distance and reef fish assemblage patterns among shipwrecks distributed around Sri Lanka. Using underwater video surveys, fish communities were documented across eight shipwreck sites, and the association between geographic distance and differences in fish assemblage composition was examined through Mantel tests.
The results revealed that geographic distance had only a limited influence on variation in fish assemblages among the shipwrecks. This suggests that spatial separation does not strongly constrain reef fish movement between these habitats. Instead, other factors, such as habitat characteristics, likely play a more important role in shaping fish assemblage structure.
These results provide evidence that shipwrecks can function as connected habitats supporting reef fish populations across broader spatial scales. The findings can support marine spatial planning and the integration of shipwreck habitats into conservation and management strategies in Sri Lanka.