Predicted decrease in global climate suitability masks regional complexity of invasive fruit fly species response to climate change

摘要

Climate change affects the rate of insect invasions as well as the abundance, distribution and impacts of suchinvasions on a global scale. Among the principal analytical approaches to predicting and understandingfuture impacts of biological invasions are Species Distribution Models (SDMs), typically in the form ofcorrelative Ecological Niche Models (ENMs). An underlying assumption of ENMs is that speciesenvironmentrelationships remain preserved during extrapolations in space and time, although this is widelycriticised. The semi-mechanistic modelling platform, CLIMEX, employs a top-down approach using speciesecophysiological traits and is able to avoid some of the issues of extrapolation, making it highly applicable toinvestigating biological invasions in the context of climate change. The tephritid fruit flies (Diptera:Tephritidae) comprise some of the most successful invasive species and serious economic pests around theworld. Here we project 12 tephritid species CLIMEX models into future climate scenarios to examine overallpatterns of climate suitability and forecast potential distributional changes for this group. We further comparethe aggregate response of the group against species-specific responses. We then consider additional driversof biological invasions to examine how invasion potential is influenced by climate, fruit production and tradeindices. Considering the group of tephritid species examined here, climate change is predicted to decreaseglobal climate suitability and to shift the cumulative distribution poleward. However, when examiningspecies-level patterns, the predominant directionality of range shifts for 11 of the 12 species is eastward.Most notably, management will need to consider regional changes in fruit fly species invasion potentialwhere high fruit production, trade indices and predicted distributions of these flies overlap.