FORAGING BEHAVIOUR BY A PARASITOID OF AN EXOTIC WOODWASP PEST UNDER INTRA AND INTERSPECIFIC INTERACTIONS

CORLEY JUAN; FISCHBEIN DEBORAH; MELISA SUANS

Congreso; INTERNATIONAL CONFERENCE TOPWOOD, ADAPTING FOREST ECOSYSTEMS AND WOOD PRODUCTS TO BIOTIC AND ABIOTIC STRESS; 2019

Competition for limited resources is a widespread ecological interaction in animals. Parasitoids, insects whose adults 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 of Megarhyssa nortoni (Hymenoptera: Ichneumonidae), an ectoparasitoid of later instars of the exotic pest woodwasp Sirex noctilio (Hymenoptera: Siricidae), under intra and interspecific competition considering their adaptive value and the impact on the population host. For this purpose, I will explore the effect of (1) direct (i.e. presence of conspecific females exploiting simultaneously the same patch) and (2) indirect (i.e. patch previously visited by conspecific females) intraspecific competition on patch residence time and oviposition behaviour in laboratory conditions, and (3) the parasitism and life history traits of adults M. nortoni developing in patches previously parasited by Ibalia leucospoides (Hymenoptera: Ibalidae), an endoparasitoid of eggs and first or second instars of the same host, in laboratory and field conditions.