Artificial reefs geographical location matters more than shape, age and depth for sessile invertebrate colonization in the Gulf of Lion (NorthWestern Mediterranean Sea)

Abstract

Artificial reefs (ARs) have been used to support fishing activities. Sessile invertebrates are essential components of trophic networks within ARs, supporting fish productivity. However, colonization by sessile invertebrates is possible only after effective larval dispersal from source populations, usually in natural habitat. We tested the relevance of geographic location, duration of immersion and depth on ARs colonization processes in the Gulf of Lion. Five species sessile invertebrates species, with contrasting life history traits and regional distribution in the natural rocky habitat, were inventoried on ARs deployed during two immersion periods (1985 and 2000-2009) and at different depths. At the local level, neither depth nor immersion duration differentiated ARs assemblages. At the regional scale, colonization patterns differed between species, resulting in diverse assemblages. This study highlights the primacy of geographical positioning over immersion duration and depth in ARs colonization, suggesting it should be accounted for in maritime spatial planning.