Distribution of non-native and native species under EWEs from 443 studies [IMAGE: GU SHIMIN]

Invasive species and extreme weather events (EWEs) are posing high impacts on global biodiversity, but their combined threat remains unclear; the first factor may be dependent on the responses of invasive species to EWEs. Compared with their native counterparts, invasive species usually have higher phenotypic plasticity, growth rates, and population recovery to quickly adapt to stressful environments. It is theoretically predicted that non-native species and native species may exhibit different responses to EWEs, but that hypothesis has never been tested in terrestrial, freshwater and marine ecosystems, where various EWE types and response mechanisms across taxonomic groups and worldwide biogeographic regions may be observed.

Sample effect sizes of non-native and native species in responding to EWEs [IMAGE: GU SHIMIN]

A recent study led by Professor Liu Xuan from the Institute of Zoology (IOZ) of the Chinese Academy of Sciences (CAS) revealed that EWEs may provide non-native species with advantages over their native counterparts. This study was published in Nature Ecology & Evolution on November 6, 2023 (16:00 GMT). Dr. Gu Shimin and master’s candidate Qi Tianyi are the first authors and contributed equally to this work. Professor Jason Rohr from the University of Notre Dame participated in the research.

Overlapping areas between potential distributions of non-native species that are tolerant of EWEs and EWE hotspots worldwide [IMAGE: QI TIANYI]

Liu Xuan and his colleagues built a database covering 187 non-native and 1,852 native species experiencing different kinds of EWEs including heatwaves, cold spells, storms, floods, and droughts across seventeen classes in terrestrial, freshwater, and marine ecosystems in the past seventy years.

Based on this comprehensive dataset, their analyses using multilevel mixed-effects meta regressions showed that, overall, responses to EWEs were more often negative among native than non-native animal populations, but that responses differed depending on the type of EWE and habitat. Both non-native and native marine animals are insensitive to EWEs, although native mollusks, corals and anemones are negatively affected by heatwaves. Non-native terrestrial and freshwater animals were only affected by heatwaves and storms, respectively, while native animals in terrestrial ecosystems respond negatively to heatwaves, cold spells and droughts, and in freshwater habitats are vulnerable to most events apart from cold spells.

Further spatial overlap analyses between EWE hotspots and existing locations of insensitive non-native species identified several locations including North America, Latin America, East and Southeast Asia, Southwest Australia and New Zealand, and west coasts and islands in the Pacific Ocean and North Atlantic Ocean, where native species may be particularly vulnerable to their joint impacts.

Under the limited resources that can be used to manage biological invasions and extreme weathers, this study highlights the necessity of prioritizing those biodiversity conservation hotspots where EWE-tolerant non-native animals and intensified EWEs are co-occurring, so that timely mitigation strategies can be implemented for alleviating the combined threats of invasive species and climate change.

For more information, please contact:

Liu Xuan

E-mail: liuxuan@ioz.ac.cn

Institute of Zoology,

Chinese Academy of Sciences

Source: Institute of Zoology,

Chinese Academy of Sciences