| Zusammenfassung: | ABSTRACT: This article replaces Sonnenholzner et al. (2007; Mar Ecol Prog Ser 343:77–85), which was retracted on September 19, 2007, due to errors in entry of data on sea urchins. We sampled 10 highly fished and 10 (putatively) lightly fished shallow rocky reefs in the southeastern area of the Galapagos Marine Reserve, Ecuador. After the correction, these are the new results: there was a negative association between slate-pencil urchinsEucidaris galapagensisand non-coralline algae. In addition, pencil urchins were less abundant where there were many predators. An indirect positive association between predators and non-coralline algae occurred. Fishing appeared to affect this trophic cascade. The spiny lobsterPanulirus penicillatus, the slipper lobsterScyllarides astori, and the Mexican hogfishBodianus diplotaeniawere significantly less abundant at highly fished sites. Urchin density was higher at highly fished sites. Non-coralline algae were nearly absent from highly fished sites, where a continuous carpet of the anemoneAiptasiasp. was recorded, and the algal assemblage was mainly structured by encrusting coralline and articulated calcareous algae.
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