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