High risk of biological invasion from prayer animal release in China

Abstract

Prayer animal release (PAR)—a traditional “compassion-based” religious practice of releasing captive animals into the wild to improve the karma of the releaser—has been regarded as a major anthropogenic pathway facilitating species invasions worldwide. However, comprehensive, quantitative assessments of PAR-related invasion risks, crucial for the development of mitigation strategies, are lacking. To address this knowledge gap, we conducted a literature review of the prevalence of PAR events and examined the overlap between PAR intensity across China and habitat suitability for non-native vertebrates released in these events. Our results revealed that 63% of the areas with high PAR intensity in China were also suitable for non-native vertebrate establishment, a degree of overlap that was greater than expected by chance. In addition, field surveys in China detected higher richness of non-native fishes at PAR sites than at non-PAR sites. These findings imply an overall high risk of biological invasions associated with PARs. We recommend interdisciplinary cooperation among scientists, religious groups, and government agencies to effectively manage PARs and reduce the associated bioinvasion risk.