期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2020
卷号：117
期号：27
页码：15397-15399
DOI：10.1073/pnas.2004805117
出版社：The National Academy of Sciences of the United States of America
摘要：Fish have somehow colonized isolated water bodies all over the world without human assistance. It has long been speculated that these colonization events are assisted by waterbirds, transporting fish eggs attached to their feet and feathers, yet empirical support for this is lacking. Recently, it was suggested that endozoochory (i.e., internal transport within the gut) might play a more important role, but only highly resistant diapause eggs of killifish have been found to survive passage through waterbird guts. Here, we performed a controlled feeding experiment, where developing eggs of two cosmopolitan, invasive cyprinids (common carp, Prussian carp) were fed to captive mallards. Live embryos of both species were retrieved from fresh feces and survived beyond hatching. Our study identifies an overlooked dispersal mechanism in fish, providing evidence for bird-mediated dispersal ability of soft-membraned eggs undergoing active development. Only 0.2% of ingested eggs survived gut passage, yet, given the abundance, diet, and movements of ducks in nature, our results have major implications for biodiversity conservation and invasion dynamics in freshwater ecosystems.
关键词：long-distance dispersal ; freshwater ; fish distribution ; invasion ; endozoochory
