Foraging behaviour by a parasitoid of an exotic woodwasp pest under intra and interspecific interactions

SUANS, MELISA; FISCHBEIN, DÉBORAH; CORLEY, JUAN

San Carlos de Bariloche

Conferencia; International Conference TOPWOOD + LIA Forestia - Adapting forest ecosystems and wood products to biotic and abiotic stress; 2019

European Union Marie Curie project TOPWOOD; INRA; INTA

Competition for limited resources is a widespread ecological interaction in animals. Parasitoids, insects whose adult females lay their eggs on or within the bodies of other insects, can interact with several organisms from their community. During foraging, both intra and interspecific competitions can occur and the behavioral decisions in searching for and parasitizing hosts have implications for the population dynamics of parasitoids and for their use as biological control agents. The interactions between foragers can influence the patch residence time and the oviposition behaviour, both linked with the fitness -lifetime reproductive success- of parasitoids. The aim of the present project is to elucidate the patch exploitation strategies by Megarhyssa nortoni (Hymenoptera: Ichneumonidae), parasitoid of the exotic pest woodwasp Sirex noctilio (Hymenoptera:Siricidae), under intra and interspecific interactions. I will explore, on the one side, the effect of direct (i.e. presence of conspecific females exploiting simultaneously the same patch) and indirect (i.e. patch previously visited by conspecific females) intraspecific competition on patch residence time andoviposition behaviour of M. nortoni; and on the other side, the parasitism and life history traits of adults M. nortoni developing in patches previously parasited by Ibalia leucospoides (Hymenoptera:Ibalidae), another parasitoid of the same host, in laboratory and field conditions. The results will be discussed in the context of classical biological control of forest insect pests.