Reassessing the presence of alien predatory mites and their prospects in the face of future climate change.

Abstract

Climate change poses uncertainties in the effectiveness of classical biological control (CBC), and there is a lack of information on the establishment of natural enemy populations under present and future climatic conditions. The objective is to explore current traces of two alien predators (Neoseiulus californicus and Neoseiulus fallacis; introduced for the CBC program in the 1980s) and their future expansion under climate change in Taiwan. The results indicated that N. californicus was present in alpine orchards (e.g., Lishan and Meifeng) but N. fallacis was not found. Under current climate condition, most areas in Taiwan were deemed highly suitable for N. californicus, but not for N. fallacis, which may explain the outcomes of the CBC program. With intensifying climate change, the ranges of both species are projected to contract to varying extents in Taiwan but expand in some countries. The findings from this study can provide insights for evaluating and developing future CBC programs worldwide, and can help predict the implications of climate change on biological control efforts. © 2023 Society of Chemical Industry.