Dynamic landscapes of fear and safety alter prey refuge use in freshwater habitats

Abstract The non-consumptive effects of predators on prey behaviour have been studied in many systems. However, predator–prey ecology has placed emphasis on how fear alters prey behaviour, and new studies have shifted focus to the importance that safety in the form of refuges has in structuring prey behavioural responses. We expanded upon the concept of safety by presenting rusty crayfish ( Faxonius rusticus ) to the cues of a natural predator, largemouth bass ( Micropterus salmoides ), to observe how sheltering behaviour is altered as a function of predator exposure pattern, shelter quality, and the spatial arrangement of shelters. Crayfish were exposed to chemical cues of the predator while the spatial arrangement of differing quality shelters was altered. We found shelter quality significantly affected crayfish sheltering time ( ). Next, we found that interactions between fish presence and shelter spatial arrangement significantly affected crayfish sheltering time ( ), as crayfish perception of risk and safety within mesocosms was heavily influenced not only by the introduction of predator odors but also by the spatial relationship between predator odours and shelters of varying qualities. These results show that safety in the form of refuges helps to inform prey decision-making in risky situations, and safety should be considered as a positive factor separate from fear in predator–prey ecology.