The synergy between climate change and transportation activities drives the propagation of an invasive fruit fly in California

Authors: ZHAO, ZIHUA - China Agricultural University; Reddy, Gadi V.P.; CHEN, LEI - China Agricultural University; QIN, YUJIA - China Agricultural University; LI, ZHIHONG - China Agricultural University

Submitted to: Journal of Pest Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/16/2019
Publication Date: 1/1/2020
Citation: Zhao, Z., Reddy, G.V., Chen, L., Qin, Y., Li, Z. 2020. The synergy between climate change and transportation activities drives the propagation of an invasive fruit fly in California. Journal of Pest Science. 93:615-625. https://doi.org/10.1007/s10340-019-01183-9.
DOI: https://doi.org/10.1007/s10340-019-01183-9

Interpretive Summary: Current globalization trends are an important contributor to biological invasions, and an effective management strategy for controlling invasive alien species is urgently needed. Detection events and infested cells infested with the oriental fruit fly fluctuated over the past 58 years and were mediated by the synergistic effects of climate change and transportation activities. The synergy effects could be used to perfectly explain the invasion dynamics of the oriental fruit fly. Additionally, continuously increasing transportation activities would further increase spatial invasions of the oriental fruit fly, especially in warmer climates. The spatial heterogeneity and passenger randomness made the prediction of invasions more difficult, which also challenges the sustainable management of the oriental fruit fly in California. Additionally, the shift of thermal tolerance and host adaptation of the pest in newly invaded areas should be examined to reveal the mechanism of the global spread of the oriental fruit fly.

Technical Abstract: Agricultural ecosystems are being increasingly exposed to the interactive effects of biological invasions, climate fluctuation and human actions, with increasing temperatures and intense transportations expected to lead to the aggravation of alien species invasions. We thus assessed this expectation for a global invasive pest, the oriental fruit fly (Bactrocera dorsalis), by determining whether climate variation and transportation activities affect invasion dynamics of this epidemic in California. We found that both temperature fluctuation (growing degree days) and transportation activities (passenger volume) have significant effects on interannual fluctuations of the oriental fruit fly detection events and infested areas. In addition, both detection events and infested areas of the oriental fruit fly were significantly higher in warmer years, while annual precipitation had no significant effects on invasion dynamics of the oriental fruit fly. The growing degree days contributed much more to the invasion dynamics than passenger volume, while passenger volume facilitated an increase in infested area more than growing degree days. Then, we introduced a conceptual framework of synergy model of climate change and transportation activities to illustrate invasion dynamics of the oriental fruit fly, revealing both the invasion dynamics in a fixed cell according to growing degree days and the spatial transmission of invasive alien species by passenger volume. Our findings shed light on the spatial invasion dynamics of alien species, with potential implications for understanding the trajectories of biological invasions under changing future climates and transportation activities.