Intra- and Interspecific Interactions among Parasitoids: Mechanisms, Outcomes and Biological Control

Insect parasitoids are a major mortality factor for their herbivore hosts. Parasitoids typically interact, within their guild and between trophic levels, with several organisms from their community. Both intra- and interspecific competitions occur and the intensity of this competition influences the population dynamics of parasitoids. A female parasitoid may face several types of competition from females of her own species or from different species or from either conspecific or heterospecific females. The strategies evolved by parasitoids to cope with competition have implications both for the population dynamics of these species and for their use as biological control agents. The response of parasitoids to the type and intensity of competition varies at the level of the species, population and individual. In addition, a female parasitoid may change her response to competition depending on the conditions under which she developed and the experience she gained.