Abstract Many sightings of the Ivory-billed Woodpecker (Campephilus principalis) have been reported during the past several decades, but nobody has managed to obtain the clear photo that is regarded as the standard form of evidence for documenting birds. Despite reports of sightings by teams of ornithologists working independently in Arkansas and Florida, doubts cast on the persistence of this iconic species have impeded the establishment of a meaningful conservation program. An analysis of the expected waiting time for obtaining a photo provides insights into why the policy of insisting upon ideal evidence has failed for this species. Concepts in statistics and probability are used to analyze video footage that was obtained during encounters with birds that were identified in the field as Ivory-billed Woodpeckers. One of the videos shows a series of events that are consistent with that species and are believed to be inconsistent with every other species of the region. Another video shows a large bird in flight with the distinctive wing motion of a large woodpecker. Only two large woodpeckers occur in the region, and the flap rate is about ten standard deviations greater than the mean flap rate of the Pileated Woodpecker (Dryocopus pileatus). Supplemental materials for this article are available online.

中文翻译：

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统计，概率和失败的保护策略

摘要在过去的几十年中，已经有许多目击过象牙的啄木鸟（CampephilusPrincipalis）的报道，但没有人能获得清晰的照片，该照片被视为记录鸟类的标准证据。尽管有报道称在阿肯色州和佛罗里达州有独立工作的鸟类学家团队目击了该物种，但对这种标志性物种的持久性的怀疑仍阻碍了有意义的保护计划的建立。通过对获取照片的预期等待时间的分析，可以了解为什么坚持理想证据的政策对该物种失败的原因。统计和概率的概念用于分析在与野外鸟类相遇时获得的录像，这些鸟类在现场被确认为象牙嘴啄木鸟。其中一个视频显示了一系列与该物种一致的事件，并被认为与该地区的其他每个物种都不符。另一个视频显示，一只大鸟在飞行中，有着一只大型啄木鸟的独特机翼。该区域仅出现两只大啄木鸟，其拍打率大约比打桩的啄木鸟（Dryocopus Pileatus）的平均拍打率大十个标准差。可在线获得本文的补充材料。并且拍打速率比打桩的啄木鸟（Dryocopus Pileatus）的平均拍打速率大大约十个标准差。可在线获得本文的补充材料。并且拍打速率比打桩的啄木鸟（Dryocopus Pileatus）的平均拍打速率大大约十个标准差。可在线获得本文的补充材料。