Скачать или смотреть Prey and predator behaviors are both affected by the prey infection [Prosnier, Loïc]

Loïc Prosnier, Nicolas Loeuille, Florence Hulot, David Renault, Christophe Piscart, Matthieu Lam, Vincent Médoc

Parasites are important components of ecosystems, altering life history traits and many interactions among species. Some effects are well known, as the reduction of fecundity and survival. Many others are less studied, as the modification of behaviors. In this work we studied the effects of a virus (DIV-1) on the Daphnia magna host. In addition to survival reduction, we observed reduction in host mobility, even when host resisted to infection. We noted many other host alterations: size, coloration and energetic content are increased. It could have repercussion on predators' diet because prey is less mobile, more visible and more energetic. Thus, we also studied implications of this infection on the predation by Notonecta sp. When D. magna are infected, Notonecta handling time is increased but search time is not modified. We also observed a higher preference for the infected D. magna. These results could be understood using Optimal Foraging Theory. Then, how prey infection could affect predators' diet was studied by a theoretical approach. Long term interaction between hosts/prey, predators and parasites could affect predator diet because prey are less available but more profitable.