Population Dynamics of the Olive Fly, Bactrocera oleae (Diptera: Tephritidae), Are Influenced by Different Climates, Seasons, and Pest Management

Pest management practices interact with many species and have an impact on the ecology and the economy of the area. In this paper, we examine the population dynamics of the olive fly, Bactrocera oleae (Rossi), Diptera: Tephritidae, on Samos Island, Greece, observing the spatial and temporal changes of the pest along an altitude associated with area-wide pest management. More specifically, we analyze data from an extended McPhail trap network and focus on experimental sites, where we monitor the pest population in relation to sprays, temperature, and relative humidity inside the tree canopy during the season for a three-year period. Our findings indicate that fly populations are influenced mostly by climate and altitude over longer periods in the season and from bait sprays for shorter periods of time, which appeared to be less effective in autumn, probably due to population movements and overlapping generations. Apart from the factors that were taken into account, such as the weather conditions and pest management regimes that were proven important, more factors will have to be considered for infestation level, such as fruit availability, inhibition factors (natural enemies, symbiotic agents, food supplies), and cultivation practices. Site microclimate conditions and the landscape can be used to explain changes at the plot level.