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Our knowledge of the eff ects of consumer species loss on ecosystem functioning is limited by a paucity of manipulative fi eld studies, particularly those that incorporate inter-trophic eff ects. Further, given the ongoing transformation of natural habitats by anthropogenic activities, studies should assess the relative importance of biodiversity for ecosystem processes across diff erent environmental contexts by including multiple habitat types. We tested the context-dependency of the eff ects of consumer species loss by conducting a 15-month fi eld experiment in two habitats (mussel beds and rock pools) on a temperate rocky shore, focussing on the responses of algal assemblages following the single and combined removals of key gastropod grazers ( Patella vulgata , P. ulyssiponensis , Littorina littorea and Gibbula umbilicalis ). In both habitats, the removal of limpets resulted in a larger increase in macroalgal richness than that of either L. littorea or G. umbilicalis . Further, by the end of the study, macroalgal cover and richness were greater following the removal of multiple grazer species compared to single species removals. Despite substantial diff erences in physical properties and the structure of benthic assemblages between mussel beds and rock pools, the eff ects of grazer loss on macroalgal cover, richness, evenness and assemblage structure were remarkably consistent across both habitats. Th ere was, however, a transient habitat-dependent eff ect of grazer removal on macroalgal assemblage structure that emerged after three months, which was replaced by non-interactive eff ects of grazer removal and habitat after 15 months. Th is study shows that the eff ects of the loss of key consumers may transcend large abiotic and biotic diff erences between habitats in rocky intertidal systems. While it is clear that consumer diversity is a primary driver of ecosystem functioning, determining its relative importance across multiple contexts is necessary to understand the consequences of consumer species loss against a background of environmental change.