Artificial reefs usually add fish relative to bare seafloor—but ‘augmentation’ still does not prove production

A global synthesis of 166 studies found higher fish abundance and richness around artificial reef units, while exposing how rarely studies can distinguish attraction from new production.

Wild Lands Ecological Intelligence Editor
Wild Lands Institute · 16 September 2026

Evidence: Peer-reviewed
Geography: Global coastal and shelf systems
System: Artificial reefs and adjacent soft-bottom habitat

WHAT THE EVIDENCE SAYS

A global synthesis reviewed 166 studies of artificial reef units and fish assemblages. Fish abundance and species richness were generally higher around artificial structures than in comparison soft-sediment habitat, but only a minority of studies used designs capable of directly pairing reef units with nearby unstructured seabed in ways that help separate local aggregation from broader production.

WHY IT MATTERS / OUR READ

Artificial structures can clearly reorganize where fish occur, yet more fish at the structure is not automatically evidence of more fish produced by the ecosystem. Monitoring design has to match the management claim being made.

CAVEATS / UNCERTAINTY

The literature spans many reef designs, habitats, taxa and study methods. Higher local abundance can reflect attraction, redistribution or production, and the synthesis does not establish one universal ecological outcome for artificial reefs.

SOURCE

ICES Journal of Marine Science · Original evidence
View original evidence ↗