Climate change effects on biological control of invasive plants by insects.

Abstract

Abstract Because many invasive plants are anticipated to benefit from climate change, the need for effective management strategies will become more pressing in the future. Biological control of invasive plants by insects has been an effective management strategy in many instances, but climate change may substantially alter such systems. Maximizing biological control efficacy with climate change will require predicting responses of the invasive plant in question, its biological control agents, and especially their corresponding interactions. However, because of the wide variety of species-specific plant and insect responses to increased atmospheric CO 2 concentrations, temperatures, extreme weather events, and other climate factors, climate change will likely result in highly variable, system- and geographically-specific effects. Even still, predicted future climates are generally anticipated across systems to alter geographic ranges of invasive plants (and correspondingly their biological agents), reduce host-plant quality, and hasten the phenology of both plants and insects. Some of these anticipated effects on biological control systems can be expected to hamper control efficacy. However, because some of these effects might also increase control efficacy, biological control can still be an effective and important management tool in the face of climate change. Although the variety of insect and plant responses to climate change reported in the literature do not currently allow for strong generalizations to be made as to the best biological control agents or strategies in novel climates, pertinent considerations for selecting effective biological control agents in the future are discussed.