Wang Qiaoyun, Han Xuesong, Wang Zichen, Zheng Kaidan, Dong Zhengyi, Zhang Peng, Fan Pengfei, Zhang Lu
School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.
State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
Curr Zool. 2023 Jun 21;70(4):472-479. doi: 10.1093/cz/zoad025. eCollection 2024 Aug.
Religious wildlife release is prevalent worldwide, especially in Asia countries. It is one of the anthropogenic pathways to cause biological invasions. Religious fish release is common on the Qinghai-Tibetan Plateau, yet few studies have assessed the influences of religious fish release on local species. In Yushu, a city on the Qinghai-Tibetan Plateau, we interviewed local people, conducted fish trap surveys in local rivers, and examined the diet of Eurasian otters using a fecal DNA metabarcoding approach. We found that fish release started at least in 1980-1990s in Yushu. Tibetan residents released fish in large amounts and released fish were usually exotic commercial fish purchased from market. Despite such long-term and intensive fish release activities, released fish were few in local rivers. On the other hand, Eurasian otters mainly prey on fish and released fish accounted for ~20% of relative read abundance of prey DNA in otters' diet, indicating their high preference on released fish. Our study suggested that religious fish release may provide additional food resources for otters, whereas otters, as a top predator in local rivers, may deplete non-native fish once they were released and, therefore, reduce the probability of colonization of released fish, although further studies are required to assess otters' impact. Our study revealed otters' diet in Yushu, providing basic information for local otter management and conservation. Furthermore, it represents a case showing that native predators prey on religious released animals, implying a probable direction for controlling invasive species through native predator conservation.
宗教放生野生动物在全球范围内都很普遍，尤其是在亚洲国家。这是导致生物入侵的人为途径之一。宗教放鱼在青藏高原很常见，但很少有研究评估宗教放鱼对当地物种的影响。在青藏高原的玉树市，我们采访了当地人，在当地河流中进行了诱捕调查，并使用粪便DNA宏条形码方法研究了欧亚水獭的饮食。我们发现，玉树的放鱼活动至少始于20世纪80年代至90年代。藏族居民大量放鱼，所放的鱼通常是从市场购买的外来商业鱼类。尽管有如此长期和密集的放鱼活动，但当地河流中的放流鱼数量很少。另一方面，欧亚水獭主要以鱼类为食，放流鱼在水獭饮食中的猎物DNA相对读取丰度中占约20%，表明它们对放流鱼有很高的偏好。我们的研究表明，宗教放鱼可能为水獭提供了额外的食物资源，而水獭作为当地河流中的顶级捕食者，一旦放流鱼被放生，可能会消耗这些非本地鱼类，从而降低放流鱼定殖的可能性，不过还需要进一步研究来评估水獭的影响。我们的研究揭示了玉树水獭的饮食情况，为当地水獭的管理和保护提供了基础信息。此外，它代表了一个本土捕食者捕食宗教放生动物的案例，暗示了通过保护本土捕食者来控制入侵物种的一个可能方向。
