Humans impose a significant pressure on large herbivore populations, such as hippopotami, through hunting, poaching, and habitat destruction. Anthropogenic pressures can also occur indirectly, such as artificial lake creation and the subsequent introduction of invasive species that alter the ecosystem. These events can lead to drastic changes in parasite diversity and transmission, but generally receive little scientific attention. In order to document and identify trematode parasites of the common hippopotamus (Hippopotamus amphibius) in artificial water systems of Zimbabwe, we applied an integrative taxonomic approach, combining molecular diagnostics and morphometrics on archived and new samples. In doing so, we provide DNA reference sequences of the hippopotamus liver fluke Fasciola nyanzae, enabling us to construct the first complete Fasciola phylogeny. We describe parasite spillback of F. nyanzae by the invasive freshwater snail Pseudosuccinea columella, as a consequence of a cascade of biological invasions in Lake Kariba, one of the biggest artificial lakes in the world. Additionally, we report an unknown stomach fluke of the hippopotamus transmitted by the non-endemic snail Radix aff. plicatula, an Asian snail species that has not been found in Africa before, and the stomach fluke Carmyerius cruciformis transmitted by the native snail Bulinus truncatus. Finally, Biomphalaria pfeifferi and two Bulinus species were found as new snail hosts for the poorly documented hippopotamus blood fluke Schistosoma edwardiense. Our findings indicate that artificial lakes are breeding grounds for endemic and non-endemic snails that transmit trematode parasites of the common hippopotamus. This has important implications, as existing research links trematode parasite infections combined with other stressors to declining wild herbivore populations. Therefore, we argue that monitoring the anthropogenic impact on parasite transmission should become an integral part of wildlife conservation efforts.

中文翻译：

---

入侵的蜗牛、寄生虫溢出和潜在的寄生虫溢出驱动津巴布韦人工湖中河马两栖动物的寄生虫病

人类通过狩猎、偷猎和栖息地破坏对大型食草动物种群（如河马）施加了巨大压力。人为压力也可能间接发生，例如人工湖的创建和随后引入的改变生态系统的入侵物种。这些事件可能导致寄生虫多样性和传播发生巨大变化，但通常很少受到科学关注。为了记录和识别津巴布韦人工水系统中常见河马 (Hippopotamus amphibius) 的吸虫寄生虫，我们应用了一种综合分类学方法，将分子诊断学和形态计量学结合在存档和新样本上。为此，我们提供了河马肝吸虫 Fasciola nyanzae 的 DNA 参考序列，使我们能够构建第一个完整的片形吸虫系统发育。我们描述了入侵淡水蜗牛 Pseudosuccinea columella 对 F. nyanzae 的寄生虫溢出，这是世界上最大的人工湖之一卡里巴湖发生级联生物入侵的结果。此外，我们报告了一种未知的由非地方性蜗牛 Radix aff 传播的河马胃吸虫。plicatula，一种以前在非洲没有发现过的亚洲蜗牛物种，以及由本地蜗牛 Bulinus truncatus 传播的胃吸虫 Carmyerius cruciformis。最后，发现 Biomphalaria pfeifferi 和两种 Bulinus 物种作为记录很少的河马血吸虫爱德华血吸虫的新蜗牛宿主。我们的研究结果表明，人工湖是传播普通河马吸虫寄生虫的地方性和非地方性蜗牛的繁殖地。这具有重要意义，因为现有的研究将吸虫寄生虫感染与其他压力源与野生食草动物种群的减少联系起来。因此，我们认为监测人为对寄生虫传播的影响应该成为野生动物保护工作的一个组成部分。