Urban and agricultural areas under threat of the termite pest genus Heterotermes: insights from species distribution modelling and phylogeny

Abstract

Termites, particularly those of the genus Heterotermes, are significant pests impacting urban and agricultural environments worldwide. Despite their impact, the distribution of Heterotermes has been largely overlooked. Our study aims to predict the potential distribution of 15 Heterotermes species by integrating bioclimatic, land-use, connectivity, soil and elevation variables into species distribution models (SDMs). These models project habitat suitability under three Shared Socioeconomic Pathways (SSP1-2.6, SSP2-4.5, SSP5-8.5) for short-term (2021–2040), mid-term (2041–2060) and long-term (2061–2080) scenarios. Our results underscore the critical influence of temperature, connectivity and soil moisture on termite distribution, revealing potential expansions into new regions due to climate change. Most parts of the Neotropics and Australia could become suitable for at least one species. Our study also examines the efficacy of incorporating phylogenetic data into SDMs, demonstrating its enhanced reliability for predicting distributions of co-occurring species, though its effectiveness diminishes for geographically isolated ones. Future projections indicate significant range shifts due to increased urbanization, agriculture expansion and climate change. Neotropical species are likely to face habitat reductions, especially in South American forests, while several Australian and major structural pest species may expand their range. Currently, densely populated cities in the Neotropics, the south-western US, Australia and South Asia could be within the range of one to five Heterotermes species. In agricultural areas, Australia and the Neotropics—both heavily reliant on agriculture—are highly vulnerable, and this vulnerability is expected to worsen as more land is converted to agricultural use.