Schooling Increases Risk Exposure for Fish Navigating Past Artificial Barriers

摘要: Artificial barriers have become ubiquitous features in freshwater ecosystems and they can significantly impact a region's biodiversity. Assessing the risk faced by fish forced to navigate their way around artificial is largely based on assays of individual swimming behavior. However, social interactions influence movement patterns alter exposure. Using an experimental flume, we assessed effects amount time required for juvenile palmetto bass (Morone chrysops × M. saxatilis) downstream past barrier. Fish were released either individually or groups into flume using flow conditions that approached limit expected stamina. We compared behaviors under solitary schooling measured as individuals spent exposed Solitary generally turned with current moved quickly barrier, while swam against displayed 23-fold increase exposure time. also showed greater signs skittish behavior than those groups, which was reflected larger changes accelerations turning profiles. While fission-fusion dynamics, inter-individual positions highly structured remained steady over These spatial align theoretical necessary reduce exertion through wake capturing velocity sheltering, but diverge from any potential gains channeling between adjacent neighbors. conclude isolated performance trials projections lead erroneous predictions along engineered structures. Our results suggest perception may be more important fish's stamina artificially modified systems.