Reefscapes of fear: predation risk and reef heterogeneity interact to shape herbivore foraging behavior

Predators can exert strong direct and indirect effects on ecological communities by intimidating their prey. The nature of predation risk effects is often context dependent, but in some ecosystems these contingencies are often overlooked. Risk effects are often not uniform across landscapes or among species. Indeed, they can vary widely across gradients of habitat complexity and with different prey escape tactics. These context-dependencies may be especially important for ecosystems such as coral reefs that vary widely in habitat complexity and have species-rich predator and prey communities. With field experiments using predator decoys of the black grouper (Mycteroperca bonaci), we investigated how reef complexity interacts with predation risk to affect the foraging behavior and herbivory rates of large herbivorous fishes (e.g., parrotfishes and surgeonfishes) across four coral reefs in the Florida Keys (USA). In both high and low complexity areas of the reef we measured how herbivory ...