CLIMEX and MEDFOES models for predicting the variability in growth potential and persistence of the Mediterranean fruit fly (Diptera: Tephritidae) populations

Authors: SZYNISZEWSKA, ANNA - University Of Cambridge; Collier, Travis; Manoukis, Nicholas; HASTINGS, JOHN - Animal And Plant Health Inspection Service (APHIS); BIGSBY, KEVIN - North Carolina State University; KRITICOS, DARREN - Commonwealth Scientific And Industrial Research Organisation (CSIRO); LEPPLA, NORMAN - University Of Florida

Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/16/2019
Publication Date: 2/11/2020
Citation: Szyniszewska, A., Collier, T.C., Manoukis, N., Hastings, J.M., Bigsby, K., Kriticos, D., Leppla, N.C. 2020. CLIMEX and MEDFOES models for predicting the variability in growth potential and persistence of the Mediterranean fruit fly (Diptera: Tephritidae) populations. Annals of the Entomological Society of America. 113(2):114-124. https://doi.org/10.1093/aesa/saz065.
DOI: https://doi.org/10.1093/aesa/saz065

Interpretive Summary: In this paper we use two different computer models to assess aspects of the biology of Mediterranean fruit fly, a highly damaging invasive pest of the US Mainland: 1) the environmental suitability of California and Florida for this pest and 2) how difficult it would be to eradicate the fly if it should invade. We examine these two factors over different times of year and under different phases of El Niño, La Niña climate cycles. Our results indicate that the most favorable periods for medfly establishment and growth are March-May and October-November in California and Florida, and that California is largely suitable in the summer with the addition of irrigation. We also find that it would take longer to eradicate medfly from California than Florida, particularly if the incursions are initiated in the summer months. La Niña years are generally less suitable for medfly in California. During the El Nino phase, the growth index remains unchanged for San Francisco, increases for Los Angeles, and decreases for Tampa and Miami. The outputs the two models is useful for preventing and controlling invasive insects, including the medfly.

Technical Abstract: CLIMEX and MED-FOES models integrate climate and medfly life history data and use it to define the environmental suitability for the pest at specific geographic locations. CLIMEX calculates growth and stress indices as indicators of climates that are suitable for medfly establishment and persistence. MED-FOES incorporates information on climate and pest management interventions and simulates the process and timing of medfly eradication. CLIMEX simulations of climatic suitability in California and Florida indicated that the most favorable periods for medfly establishment and growth are March-May and October November, whereas the environment would be highly stressful during the summer months, except when irrigation is included. With irrigation, California is largely suitable for Medfly during the summer. Medfly populations will decline significantly in January-February in Los Angeles, Tampa and Miami and probably not survive in San Francisco. Based on MED-FOES simulations, it would take longer to eradicate medfly from California than Florida, particularly if the incursions are initiated in the summer months. Medfly annual growth indices for the ENSO La Nina years are relatively low for San Francisco and Los Angeles but are above neutral for Tampa and very high for Miami. During the El Nino phase, the growth index remains unchanged for San Francisco, increases for Los Angeles, and decreases for Tampa and Miami. The temperature indexes increase from San Francisco to Los Angeles and Tampa to Miami, with California lower than Florida. The outputs of CLIMEX and MED-FOES models is useful for preventing and controlling invasive insects, including the medfly.