信息素和赤链蛇对入侵种北美牛蛙控制效果研究

American bullfrog (bullfrog, Lithobates catesbeianus = Rana catesbeiana) is an notorious globally invasive species,listed as one of "100 of world's worst invasive alien species" by Invasive Species Specialist Group (ISSG/IUCN)and one of "the 16 most invasive species" in China. Bullfrogs have invaded Zhejiang, Yunnan, Sichuan, Guizhou and Shanxi in large number. Bullfrog invasions not only have led to rapid population declines,distribution shrinking and local extinctions of local amphibians and reptiles in the invaded countries included China or invaded areas, but also destroied structures of local aquatic ecosystems. There is urgently needed for the development of control measurements of bullfrog populations in invaded ranges for conserving local biodiversity. Focused on bullfrog-invaded areas of Zhoushan Archipelago where long-term study has been conduced, this project will estimate control effects of bullfrog pheromone and local enemy red banded snake (Dinodon rufozonatum) on bullfrog populations using behavioural ecology and chemical analysis approaches. The project will also explore how to reduce negative effects of such control measurements on native amphibians when using pheromone and the enemy in invaded ranges. The aim of this project is to develop novel, economical and environment-safe control measurements of bullfrogs.

北美牛蛙(American bullfrog, Lithobates catesbeianus = Rana catesbe iana)是极具危害的入侵种，已被自然保护联盟入侵种专家组列为全球100种危害最大的外来种，也是我国公布的16种最具威胁的入侵种之一。牛蛙已在浙江、云南、四川、贵州和山西等省大范围入侵成功并快速扩展。牛蛙入侵已引起包括我国在内的许多国家和地区蛙类和蛇类种群的严重下降、分布区缩小和局部绝灭，并破坏水生生态系统的结构。发展控制牛蛙的有效途径和方法是各入侵区生物多样性保护的当务之急。本申请应用行为生态学和化学分析的方法，以有牛蛙长期研究基础的舟山群岛为研究区域，探索牛蛙的信息素对牛蛙蝌蚪以及当地天敌赤链蛇对牛蛙成体和亚成体的控制效果；研究使用信息素和赤链蛇时如何减少它们对当地两栖动物的不利影响；发展新的、经济的、环境安全及有效的牛蛙控制途径。

北美牛蛙(Lithobates catesbeianus)入侵已引起当地蛙类和蛇类种群的下降，破坏了水生生态系统的结构。发展控制牛蛙的有效方法是生物多样性保护的当务之急。本项目以有牛蛙长期研究基础的舟山群岛为研究区域，探索牛蛙的信息素对牛蛙蝌蚪以及当地天敌赤链蛇（Dinodon rufozonatum）对牛蛙成体和亚成体的控制效果。在信息素控制牛蛙蝌蚪研究方面，发现牛蛙卵和成体皮肤分泌物对其蝌蚪具有一定的吸引力，但吸引反应比蔗蟾蜍(Rhinella marina)实验表现得弱，暗示可以利用它们在入侵地选择性地去除牛蛙。但牛蛙卵物质或皮肤分泌物在野外水体吸引牛蛙蝌蚪的效果并不显著，可能原因是信息素浓度不够，或特异性不强，或水体太大对信息素有稀释作用。这些结果为未来寻找高效特异的信息素提供了基础数据。在赤链蛇控制牛蛙研究方面，发现赤链蛇最偏好捕食牛蛙，无论从生物量和个体数量方面均是如此，其次是黑斑侧褶蛙（Pelophylax nigromaculatus）和泽蛙（Fejervarya limnocharis），赤链蛇避免捕食中华大蟾蜍（Bufo gargarizans）。赤链蛇捕食牛蛙的量为1-8个个体/成蛇/4周，蛇的个体大，捕食量大。赤链蛇偏好永久性静水水体。野外实验发现，赤链蛇被释放到水体后，很难再发现和捕获，可能原因是赤链蛇的归家行为非常强，快速返回了其原生境。我们的结果为利用当地天敌控制牛蛙提供了重要数据。