Nest predation is the main cause of reproductive failure in many bird species. Identification of predators is crucial to understand and interpret the factors that affect nest predation. Although nest predation is a natural top-down regulator of bird populations, its effect is usually more dramatic when introduced predators are involved, particularly in oceanic islands. In the Azores archipelago, the endemic Azores Woodpigeon (Columba palumbus azorica) is believed to be under high predation pressure. We used motion-triggered cameras to monitor nests of the Azores Woodpigeon on two islands of the archipelago (Pico and Terceira) in order to identify nest predators, quantify their impact on this bird and better understand the determinants of predation rates. We sampled 56 nests, during 569 camera trap days, obtaining around 125,000 photographic records. Two introduced predators were identified, black rat (on both islands) and feral cat (only on Terceira), both depredating eggs and chicks. Breeding success, calculated using the Mayfield method, was estimated at 19% on Pico and only 9% on Terceira. Overall, predation was the main cause of breeding failure. General linear models showed that predation rates are positively correlated to fruit availability and negatively correlated to elevation, human population density and adult Woodpigeon attendance at the nest. Edge distance, nest height or cover of trees did not affect predation. Camera traps also provided additional and useful information on predator behaviour when approaching a nest and on daily activity patterns of both adult Woodpigeon and nest predators.

巢捕食是许多鸟类繁殖失败的主要原因。识别掠食者对于理解和解释影响巢捕食的因素至关重要。尽管鸟巢捕食是自然的自上而下的鸟类种群调节器，但是当涉及引入的捕食者时，其影响通常会更为显着，特别是在大洋岛屿中。在亚速尔群岛，特有的亚速尔群岛自然斑鸠（Columba palumbus azorica）被认为处于高压捕食状态。我们使用运动触发式摄像机来监视群岛两个岛屿（皮克和特塞拉）上的亚速尔群岛斑鸠的巢，以识别巢捕食者，量化它们对这只鸟的影响，并更好地了解捕食率的决定因素。我们在569个相机陷阱天内对56个巢进行了采样，获得了约125,000张摄影记录。确定了两个引进的捕食者，黑鼠（在两个岛上）和野猫（仅在特塞拉），都在捕食卵和小鸡。使用Mayfield方法计算的育种成功率在Pico估计为19％，在Terceira仅为9％。总体而言，掠食是繁殖失败的主要原因。一般线性模型显示，捕食率与水果供应量呈正相关，与海拔高度呈负相关，人口密度和成年Woodpigeon在巢中的出勤率。边缘距离，巢高度或树木的覆盖率均不影响捕食。相机陷阱还提供了有关接近巢时捕食者行为以及成年Woodpigeon和巢捕食者日常活动模式的其他有用信息。