title: Effects of fish cues on mosquito larvae development.
abstract: We investigated the effects of predator-released kairomones on life history traits of larval Culex pipiens (Linnaeus). We compared the development time and survival of sibling larvae, reared in either water conditioned by the presence of Gambusia affinis (Baird and Girard) or fishless control-water. Our results indicate that larvae developing in fish-conditioned water (FCW) pupated faster than larvae in fishless-control water. The effect of FCW on larval survival was evident only in females. Surprisingly, FCW increased female survival. In both development-time and survival, boiling the water eliminated the FCW effect, supporting our hypothesis that fish conditioning is based on kairomones. Accelerated metamorphosis in response to predator released kairomones, evident in our results, is a rarely described phenomenon. Intuitively, when exposed to predator associated signals, aquatic larvae should metamorphose earlier to escape the higher risk of predation. However, theoretical models predict this outcome only under specific conditions. Indeed, longer - rather than shorter - time to metamorphosis is usually observed in response to predation risk. We argue that the response of larval mosquitoes to predation risk is context-dependent. Shortening larval development time may not be an exceptional response, but rather represents a part of a response spectrum that depends on the level of predation risk and resource abundance.
authors.affiliation: Center for Biological Control, Department of Life Sciences, Ben-Gurion University of the Negev, Israel. Electronic address: alonsil@gmail.com.
authors.forename: Alon
authors.initials: A
authors.lastname: Silberbush
authors.affiliation: Center for Biological Control, Department of Life Sciences, Ben-Gurion University of the Negev, Israel.
authors.forename: Zvika
authors.initials: Z
authors.lastname: Abramsky
authors.affiliation: Center for Biological Control, Department of Life Sciences, Ben-Gurion University of the Negev, Israel; Department of Life Sciences, Achva Academic College, Israel.
authors.forename: Ido
authors.initials: I
authors.lastname: Tsurim
mesh_terms: D000818:Animals; D003463:Cues; D003465:Culex / Q000502:physiology*; D005260:Female; D005399:Fishes; D007814:Larva / Q000254:growth & development; D008297:Male; D010675:Pheromones / Q000378:metabolism*; D011235:Predatory Behavior
chemical_list: D010675:Pheromones
keywords: Culex pipiens; Life history; Phenotypic plasticity; Predator cues