Non-consumptive effects of predator and conspecific exudates on different stages of an encapsulating gastropod

Prey can detect chemical cues from predators or injured conspecifics, triggering non-consumptive effects (NCEs) that influence behavior, physiology, or life-history traits. This study examined NCEs on the slipper limpet Crepipatella peruviana by measuring oxygen consumption rate (OCR) and clearance rate (CR) at three life stages (encapsulated larvae, males, and females). Individuals were exposed to exudates from two predators: the seastar Meyenaster gelatinosus (a top predator in wave-exposed coastal environments) and the gastropod Argobuccinum pustulosum (a sympatric predatory snail), as well as from injured conspecifics. We also assessed the actual predation capacity and attack rates of both predators on C. peruviana. Results showed no NCEs induced by M. gelatinosus exudates, likely due to habitat segregation preventing prey recognition. Conversely, exposure to A. pustulosum exudates increased OCR in larvae and females and increased CR in males, while females showed decreased CR. Injured conspecific exudates caused a reduction in CR in females, without affecting OCR. Predation trials revealed M. gelatinosus attacked prey only when detached from the substrate (0.5 individuals/day), while A. pustulosum effectively attacked substrate-attached prey (0.34 individuals/day) by shell perforation. These findings suggest that C. peruviana can detect and respond physiologically to certain predator cues, potentially as escape or antipredatory mechanisms, while the absence of response to M. gelatinosus may be explained by limited ecological overlap.