The potential global distribution of Chilo partellus, including consideration of irrigation and cropping patterns

Abstract

Chilo partellus is a major crop pest in Asia and Africa, and has recently spread to the Mediterranean region. Knowledge of its potential distribution can inform biosecurity policies aimed at limiting its further spread and efforts to reduce its impact in areas that are already invaded. Three models of the potential distribution of this insect have been published, each with significant shortcomings. We re-parameterized an existing CLIMEX model to address some parameter inconsistencies and to improve the fit to the known distribution of C. partellus. The resulting model fits the known distribution better than previous models, highlights additional risks in equatorial regions and reduces modelled risks in wet and extremely dry regions. We bring new insights into the role of irrigation in the potential spread of this invasive insect and compare its potential distribution with the present known distribution of its hosts. We also distinguish regions that are suitable for supporting persistent populations from those that may be at risk from ephemeral populations during favourable seasons. We present one of the first demonstrations of a new capability in CLIMEX to automatically estimate parameter sensitivity and model uncertainty. Our CLIMEX model highlights the substantial invasion risk posed by C. partellus to cropping regions in the Americas, Australia, China, Europe, New Zealand and West Africa. Its broad host range and reported impacts suggest that it should be a pest of significant concern to biosecurity agencies in these presently uninvaded regions.

Including irrigation in niche modelling of the invasive wasp Vespula germanica (Fabricius) improves model fit to predict potential for further spread

“…This modelling technique [50–52] is likely to yield significant improvements to niche models of most agricultural pests, diseases and weeds.…”

Impacts of climate change and host plant availability on the global distribution of Brontispa longissima (Coleoptera: Chrysomelidae)

“…Wet stress (WS) is defined by the wet stress threshold (SMWS) and wet stress rate HWS), and restricts the species distribution in the case of excessive soil moisture . SMWS was set to 2.5 based on SM3.…”

“…Wet stress (WS) is defined by the wet stress threshold (SMWS) and wet stress rate HWS), and restricts the species distribution in the case of excessive soil moisture. 16 SMWS was set to 2.5 based on SM3. Distribution records denote that B. longissima can survive in wet areas; therefore, integrating with wet tropical template parameters, a low HWS of 0.002 week −1 was set to ensure that the potential distribution in the model was consistent with the known geographical distribution.…”

“…Various ecosystem changes have occurred globally due to the temperature rise, among which changes in insect distributions have caused problems worldwide . Recent studies show that climate change will alter the geographic distributions of many insects and increase the risk of invasion to new regions, leading to serious damage to ecosystems and huge economic losses …”

“…11 Various ecosystem changes have occurred globally due to the temperature rise, among which changes in insect distributions have caused problems worldwide. 12 Recent studies show that climate change will alter the geographic distributions of many insects and increase the risk of invasion to new regions, [13][14][15][16][17] leading to serious damage to ecosystems and huge economic losses. 13,18 The identification of the geographical distribution that is suitable for pests under climate change scenarios is essential for the development of long-term management strategies.…”