Modeling the climatic suitability for Fopius arisanus (Hymenoptera: Braconidae) and its host fly Bactrocera dorsalis (Diptera: Tephritidae)

Abstract

Releases of the parasitoid Fopius arisanus (Sonan) (Hymenoptera: Braconidae) have significantly reduced fruit fly populations, especially for its preferred host Bactrocera dorsalis (Hendel) (Diptera: Tephritidae, Dacinae) in climatically suitable areas where the species can become established for long-term control. The maximum entropy model (MaxEnt) was used to create niche models to find overlapping regions of climatic suitability for B. dorsalis and F. arisanus to pinpoint suitable release locations. Models for both species performed very well. Temperature seasonality contributed the most to the fly model, followed by precipitation of the wettest quarter, which also had the highest gain for the parasitoid model. The calculated niche overlap between the two species was high. The parasitoid model had less climatic suitability than for B. dorsalis. According to the fly model, parts of the Mediterranean, the Americas, most of Sub-Saharan Africa, northern China, and northern Australia are at risk for invasion. Suitable parasitoid release locations include parts of the Americas, regions of Sub-Saharan Africa, and coastal Queensland. Previously proposed release locations in most of California, Peru, and Argentina were unsuitable.