title: Parasite-induced alteration of odour responses in an amphipod-acanthocephalan system.
abstract: Odour-related behaviours in aquatic invertebrates are important and effective anti-predator behaviours. Parasites often alter invertebrate host behaviours to increase transmission to hosts. This study investigated the responses of the amphipod Hyalella azteca when presented with two predator chemical cues: (i) alarm pheromones produced by conspecifics and (ii) kairomones produced by a predatory Green Sunfish (Lepomis cyanellus). We compared the responses of amphipods uninfected and infected with the acanthocepalan parasite Leptorhynchiodes thecatus. Uninfected amphipods reduced activity and increased refuge use after detecting both the alarm pheromones and predator kairomones. Infected amphipods spent significantly more time being active and less time on the refuge than uninfected amphipods, and behaved as if they had not detected the chemical stimulus. Therefore, L. thecatus infections disrupt the amphipods' anti-predator behaviours and likely make their hosts more susceptible to predation.
authors.affiliation: Colorado State University, Department of Biology, Building 1878, Fort Collins, CO 80523, USA. Electronic address: cfstone@rams.colostate.edu.
authors.forename: Charles F
authors.initials: CF
authors.lastname: Stone
authors.affiliation: Colorado State University, Department of Biology, Building 1878, Fort Collins, CO 80523, USA.
authors.forename: Janice
authors.initials: J
authors.lastname: Moore
mesh_terms: D000049:Acanthocephala / Q000502:physiology*; D033304:Amphipoda / Q000469:parasitology* / Q000502:physiology*; D000818:Animals; D059001:Aquatic Organisms / Q000469:parasitology; D001522:Behavior, Animal; D003463:Cues; D006790:Host-Parasite Interactions / Q000502:physiology; D009812:Odorants; D010675:Pheromones / Q000494:pharmacology*; D011235:Predatory Behavior
chemical_list: D010675:Pheromones
keywords: Alarm pheromones; Leptorhynchoides thecatus; Manipulation; Olfactory predator cues; Parasitism; Predator kairomones