2007 Annual Report 1a.Objectives (from AD-416) Tephritids of the genus Anastrepha are potentially invasive species whose establishment would severely impact the fruit-growing economy of the USA. Knowledge of natural enemies and the development of biological control strategies are necessary to both prepare for eventual invasion and to limit the likelihood of invasion through suppression of populations in neighboring countries. 1b.Approach (from AD-416) Long term field and laboratory studies will be pursued in order to determine the environmental conditions preferred by both pests and their predators and parasitoids. In addition, sexual, feeding and host-foraging behaviors will be described in order to choose the best candidate natural enemies for conservation, introduction and mass-rearing and inundative release under a variety of conditions. 3.Progress Report This report serves to document research conducted under an unfunded cooperative agreement between ARS and the Instituto de Ecologia (Xalapa, Veracruz, Mexico). Additional details may be found in the report for the parent project #6615-22000-021-00D; Biologically-Based Technologies for Management of Crop Insect Pests in Local and Area-wide Programs. The ADODR has monitored activities and cooperated in planning research for this project through extended visits between the PI and collaborators and through email and telephone correspondence. The ADODR has provided technical guidance to students participating in this research. Research conducted under this unfunded agreement addresses issues concerning the management of invasive tephritid fruit flies, specifically the ecology and behavior of parasitic Hymenoptera that are candidates for biological control programs. In the past year students and postdoctoral associates at both laboratories have participated. In the past year, parthenogenesis (all-female offspring) in a parasitoid species has been ascribed to a Wolbachia bacterium that lives inside the wasp’s cells. Additional studies have looked at volatiles that come from fruit and their influence of parasitoid searching for food and oviposition sites, and the role of diet on the number of eggs a female parasitoid can produce under mass-rearing conditions. This research supports NP 304 Crop protection and Quarantine, Components III (Plant, Pest and Natural Enemy Interactions and Biology), and V (Component V: Pest Control Technologies).