The effect of waterfowl signals andPseudocorynosoma enriettiinfection on the behaviour of the amphipodHyalella patagonica

Abstract

AbstractIn the present study, we sought to determine whether i) a waterfowl signal induces avoidance behaviour of the amphipodHyalella patagonica, ii) infection by the acanthocephalanPseudocorynosoma enriettiaffects the behaviour of the amphipod, and iii) the parasite interferes with the amphipod response to waterfowl. We evaluated amphipod behaviour experimentally by measuring activity levels, phototaxis, geotaxis, and clinging behaviour. The main findings of this study indicate that uninfected amphipods show avoidance behaviour by reducing their activity in the presence of a predator signal. Secondly, infected amphipods show altered behaviour, such as swimming in bright areas near the water surface, which makes them more visible to predators in nature. Lastly, the presence of predatory cues causes infected amphipods to drop to the bottom, which increases their visibility to predators. The present research allows us to perceive the intricate interplay among predators, parasites, and their intermediate hosts and advance our understanding of these complex ecological dynamics.