Can ocean acidification interfere with the ability of mud snails (Tritia obsoleta) to sense predators?

Abstract

Nonlethal predator-prey interaction between Dyspanopeus sayi (northern mud crab) and Tritia obsoleta (mud snail) under ocean acidification conditions (OA) were investigated. Nonlethal interactions can influence predator-prey relationships and magnify the ecological impact of predators in marine habitats. Future increases in OA necessitate an understanding of how prey perceive the threat of predation and how this may be impacted by ocean acidification. In baseline experiments at pH 8.1, mud snails responded differently to crab cues compared to crushed conspecifics, burying in the presence of crushed conspecifics and fleeing in the presence of a mud crab. While many predator cue experiments combine these two types of cues, these results suggest that mud snails not only discern between threat cues but also have a nuanced response that is tailored to specific threats. Mud snail responses to predator-prey relationships were delayed under lower pH conditions, as snails in acidified treatments did not exhibit any of the escape responses that they commonly displayed under control conditions. Thus, acidification could shift predator-prey relationships and significantly alter food webs under acidified conditions.