寄生对地面巢捕食风险的影响

巢捕食和巢寄生是大多数鸟类巢失败的主要原因，同时也是影响和改变鸟类生活史策略和行为的重要选择压力。巢捕食理论认为巢的暴露会增加巢被捕食的风险，而巢寄生者在雏期会表现出对寄主的拱卵或拱雏行为、大声高频乞食和延时离巢出飞行为，这些行为会暴露巢位置并招致潜在捕食者的风险。地面巢捕食率本就很高的情况下，加上上述寄生者的特殊繁殖行为作为诱因，无疑会进一步增加地面巢的捕食风险。为此，我们选择大杜鹃（Cuculus canorus）及其3种地面寄主鸟巢为研究对象，对比寄生巢与非寄生巢在孵化和育雏阶段的捕食情况，总结并揭示寄生对地面巢捕食风险的影响，并进一步探索和发现地面巢反捕食和反寄生的生活史策略。我们预期，寄生巢捕食率会明显高于非寄生巢，被捕食的速率将会更快，捕食者将会有所差异，同时，巢寄生率会较低。此研究将让我们进一步了解地面巢捕食的情况，同时会丰富和增进人们对巢寄生和巢捕食理论的理解。

Nest predation and brood parasitism are the primary sources of nest failure for most bird species，meanwhile are the important selective pressure in influencing and changing avian life history strategy and behaviour. Nest predation hypothesis believe that nest exposure will incur the cost of nest predation risk, and yet the parasite showed the supernormal behaviour include tossing egg/nestling behaviour, loud and rapid begging, and time-delay leaving the nest, these behaviours will expose the nest location and incur the potential predator. The ground-nest originally has a high predation rate, combined with the above mentioned special behaviour of parasites nestling, which undoubtedly will increase the ground-nest predation risk. Therefore, we compare the predation cases between parasitized and non-parasitized nests in common cuckoo Cuculus canorus and their three ground-nesting hosts, that will reveal the influence of nest predation risk in ground-nest by avian brood parasitism, furthermore, we explore and discover the life history strategies of counter predation and anti-parasitism. We predict that the parasitized nests predation rate obviously higher than the non-parasitized nests, the predation speed would more rapid and the predator would different in body size, also the parasitism rate would lower. This study would significantly improve our knowledge of parasite-host system and nest predation theory, meanwhile better understand the predation risk of ground-nesting birds.