Environmental DNA reveals biotic homogenization alongside elevated native and non-native species richness in marinas, supporting an ecological portuarization syndrome

Environmental DNA metabarcoding in 12 marinas in the north-western Mediterranean Sea finds higher animal species richness than adjacent natural habitats, including among native species.

• Why it matters: Ports and marinas may reshape biodiversity through environmental conditions and ongoing introductions of non-indigenous species, but the ecological signature of the biological portuarization syndrome is poorly quantified.
• What they did: The study used eDNA metabarcoding with three markers to profile 536 species across 18 phyla, including 50 non-indigenous or cryptogenic taxa, comparing marinas versus nearby natural habitats.
• The result: Assemblages differed in taxonomic and functional composition, marinas showed more homogeneous community structure than natural habitats, and the richness pattern held across most phyla.

AI summary of the abstract · may contain errors · not medical advice · read the paper.