Anti-predator responses of amphipods are more effective in the presence of conspecific chemical cues

摘要: Predators have been widely demonstrated to influence developmental plasticity in aquatic prey. We investigated the body size of amphipod Hyalella azteca raised with predatory sunfish by exposing solitary or groups three amphipods kairomones a control for 30 days. Field studies indicate that small H. is likely an adaptive response size-selective predation. Grouped chronically exposed had significantly smaller lengths than grouped controls, while individual exhibited no significant differences. Behavioral trials revealed sought refuge less amphipods. To examine if conspecific chemical cue was related reduction kairomones, were combination cues and controls Amphipods length alone. These results mirrored group versus exposure experiment, suggesting required induce anti-predator response. The present study highlights importance plastic responses predators.