CLIMEX modelling for risk assessment of Asian fruit fly, Bactrocera papayae (Drew and Hancock, 1994) in India

Abstract

Aim: Risk of establishment of Asian fruit fly, Bactrocera papayae (Drew and Hancock, 1994) an alien species to India was made for the present and expected climate change situations of 1 °C, 2 °C and 3 °C rise in global temperatures using CLIMEX, a bioclimatic modelling tool. Methodology: CLIMEX, the bioclimatic model was run for 33 known geo-referenced home locations of B. papayae using "regional match climate" function in order to predict the areas with similar Climate Match Index, (CMI > 0.7). The model was also run with rise in temperature of 1 °C, 2 °C and 3 °C for predicting the risk areas for B. papayae establishment, in case gets introduced accidentally. Results: High climatic similarity was predicted for most parts of South East Asia, Africa, South America, few parts of Australia, North Western Europe, North and Central America. In India, a climate match of >0.7 was predicted for the states of Karnataka, Tamil Nadu, Andhra Pradesh, Telangana, Orissa, Bihar, Jharkhand, West Bengal, Maharashtra, Kerala and Chhattisgarh, which could be potential hot spots for B. papayae, if introduced accidentally. In India, with the rise in temperatures from 1 °C to 3 °C, there was a gradual decrease in the climate similarity for the pest establishment particularly in the coastal regions of Tamil Nadu and Andhra Pradesh. However, the climate similarity was projected to increase in the coastal parts in the states of Karnataka and Maharashtra with 3 °C rise in temperature, making the regions more suitable for pest establishment. Interpretation: Present findings emphasises the need for close monitoring in the regions predicted to have congenial climatic conditions for B. papayae and needs strict quarantine measures against this pest.