Predatory blue crabs induce stronger nonconsumptive effects in eastern oysters Crassostrea virginica than scavenging blue crabs

摘要: By influencing critical prey traits such as foraging or habitat selection, predators can affect entire ecosystems, but the nature of cues that trigger reactions to are not well understood. Predators may scavenge supplement their energetic needs and scavenging frequency vary among individuals within a species due preferences availability. Yet consumers primarily scavengers versus those active foragers have been investigated, even though variation in might influence cascading nonconsumptive effects food webs. Oysters Crassostrea virginica react crab by growing stronger shells. We exposed oysters exudates from crabs fed live aged oyster tissue simulate scavenging, controls without cues. grew shells when either exudate, were significantly oysters. The response than could be inherent differences diet representative reduced risk presence degradation conspecific alarm treatments, which mask potential subsisting scavenging.