Raw water transfers: why a global freshwater invasion pathway has been overlooked

Abstract

Zhu et al. (Science 380:1230, 2023, https://doi.org/10.1126/science.adi6022) recently reported in Science that ‘water diversions’ carry a range of freshwater invasive non-native species (INNS) in China, and make calls for the Chinese government to take actions to monitor this invasion pathway and prevent future spread. This issue is not confined to China however. Water diversions, more commonly known internationally as ‘water transfers’ or ‘raw water transfers’, exist globally in large numbers. Despite worldwide occurrence, this major invasion pathway has received little attention within the field of freshwater ecology or invasion ecology, beyond a limited number of regional studies which offer little context regarding the global nature of the pathway. We discuss the factors contributing to the widespread lack of awareness of this uniquely complex invasion pathway, and emphasise the importance of future collaboration and knowledge sharing in this emerging field. Transdisciplinary research is needed to develop effective management techniques for this invasion pathway and ensure that the threat to global freshwater biodiversity posed by INNS is dealt with comprehensively.