Predation and brood parasitism are common reasons for nesting failure in passerine species and the additive impact by invasive species is a major conservation concern, particularly on tropical islands. Recognising the relative contribution of the different components of nesting failure rates is important to understand co‐evolutionary interactions within brood parasite–host systems. In the remote archipelago of New Caledonia, the fan‐tailed gerygone Gerygone flavolateralis is the exclusive host of the brood‐parasitic shining bronze‐cuckoo Chalcites lucidus. Additionally, invasive rodents also possibly have an impact on breeding success. To estimate the impact of potential nest predators, we 1) video monitored nests to identify predators, 2) estimated the probability of predation based on nest visibility and predator abundance and 3) tested the possibility that the location of experimental nests and lack of odour cues decrease the predation by rodents. In addition, we estimated nest survival rates using data collected in different habitats over the course of eight breeding seasons. Nesting success of fan‐tailed gerygones was relatively low and predation was the main cause of nesting failure. We recorded mainly predation by native birds, including the shining bronze‐cuckoo, whereas predation by rats was rare. In open habitats predation by cuckoos was much lower than predation by other avian predators. Neither predator activity around nests nor nest visibility influenced the probability of predation. Experimental nests in more accessible locations and containing an odorous bait were more exposed to rodent predation. Apparently, the fan‐tailed gerygone has either never been specifically vulnerable to predation by rats or has developed anti‐predator adaptations.

中文翻译：

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孵化场寄生和捕食对新喀里多尼亚扇尾灰鼠的巢生存的影响

捕食和繁殖体寄生是雀形目物种筑巢失败的常见原因，入侵物种造成的累加影响是主要的保护问题，特别是在热带岛屿上。认识到嵌套失败率的不同组成部分的相对贡献对于理解亲代寄生虫-宿主系统内的协同进化相互作用非常重要。在新喀里多尼亚偏远的群岛中，扇尾的灰熊黄松黄酮是繁殖寄生的，闪亮的青铜杜鹃Chalcites lucidus的独家寄主。此外，侵入性啮齿动物也可能对育种成功产生影响。为了估算潜在的巢穴掠食者的影响，我们1）通过视频监控的巢穴来识别掠食者，2）根据巢穴的可见度和捕食者丰富度估计掠食的可能性，以及3）测试实验巢穴的位置和缺乏气味提示的可能性减少啮齿动物的捕食。此外，我们使用八个繁殖季节过程中在不同栖息地收集的数据来估算巢生存率。扇形尾ery的筑巢成功率相对较低，掠食是筑巢失败的主要原因。我们主要记录了本土鸟类的捕食，包括闪闪发光的青铜杜鹃，而老鼠的捕食却很少。在开放的栖息地，杜鹃的捕食比其他鸟类的捕食者的捕食要低得多。巢周围的捕食者活动或巢的可见性都不会影响捕食的可能性。在更容易接近的位置并含有臭味诱饵的实验巢更容易受到啮齿动物的捕食。显然，扇尾灰鼠草从来没有特别容易受到老鼠的捕食，也没有发展出反捕食者的适应能力。