Attraction versus production in restoration: spatial and habitat effects of shellfish reefs for fish in coastal seascapes

Restored shellfish reefs provide valuable habitat for fish, but it is not clear how different approaches affect performance, and either promote the development of new fish populations (i.e. “production”) or simply attract individuals from broader seascape “attraction”). We measured effects a 1.5 ha reef restoration site on assemblages in Pumicestone Passage eastern Australia, which contains replicates six units: shell patch reefs, crates shells, biodegradable matrix, each had with without live oysters. Fish were surveyed before then every 6 months 30 baited (at control sites) unbaited 106 sites across to detect potential attraction, at units) underwater cameras. Shellfish represents an addition carrying capacity two key reasons. First, significantly enhanced diversity abundance density harvestable by 3.8, 10.7, 16.4 times, respectively. Second, distributions did change response succession site. differ between units presence absence These findings further support notion that restored enhance can overall seascapes rather than centralizing them sites.