The impact of increased turbidity, as a result of global climate change, on the stress and alarm signaling in the crayfish, Orconectes virilis.

Abstract

The objective of this study was to investigate the influence potential increasing suspended sediment loads due to global climate change could have on Orconectes virilis chemical communication. Experiments were designed to determine if suspended sediment triggers an increase in the quantity of chemical stress signals that crayfish release voluntarily under stressful environments. As well as determine if crayfish behavior is altered when exposed to chemical stress signals and damage-induced signals under turbid water conditions. In order to determine if suspended sediment triggers an increase in urine quantity crayfish were catheterized and exposed to clear water as well as turbid water in separate treatments. The influence of suspended sediment on the behavior of conspecifics exposed to both stress signals and alarm signals was determined by monitoring behavior in a Y-maze experimental stream. This Y-maze consisted of two separated arms to allow for the simultaneous input of clear and turbid with holding tanks for conspecifics to release chemical signals. First, crayfish exposed to turbid water conditions released urine quantities that were similar to that of crayfish exposed to clear water conditions. The behavior of conspecifics exposed to damage-induced alarm signals in turbid water showed no difference from the behavior of conspecifics exposed to these chemicals in clear water conditions. This indicates that Orconectes virilis disturbance chemical communication is tolerant to turbid water conditions for at least short durations of time.