Coastal eutrophication as a potential driver of functional homogenization of copepod species assemblages in the Mediterranean Sea

Abstract

• Passive ambushing copepods were favored as Chl a increased. • Generalist feeders were favored as Chl a increased showing trophic homogenization. • Trait-based approaches are useful to study the effect of eutrophication on copepods. Eutrophication as a consequence of anthropogenic nutrient enrichment is one of the major threats to biodiversity in nearshore and coastal marine waters, and consequently, for ecosystem functioning. This study explores changes in the biological organization of copepod assemblages along a Chl a gradient through an upscaling analysis of regional datasets from the coastal waters of the Mediterranean Sea. Results show that omnivorous copepods using passive and/or ambush feeding strategy are favored as Chl a increases, and copepod community shifts towards trophic homogenization by favoring generalist feeders against specialists. To our knowledge, this is the first report of functional homogenization of copepods as the result of eutrophication. The present study also demonstrates the potential use of trait-based approaches to explore the effect of human disturbances on marine copepod assemblages in marine ecosystems.