Imperfect detection is ubiquitous among wildlife research and is therefore commonly included in abundance estimation. Yet, the factors that affect observation success are largely unknown for rare and elusive species, such as large carnivores. Here, we took advantage of intensive ground‐based monitoring effort and an extensive GPS data set (2000–2018) and developed a winter sightability model for gray wolves (Canis lupus) in northern Yellowstone National Park, Wyoming, USA. Our resulting sightability model indicated that observation success was positively affected by the topographic nature of where wolves were in relation to observer locations (viewshed), areas being less forested (openness), and wolf group size, and negatively affected by distance from observer locations. Of these, viewshed had the strongest effect on the probability of observing a wolf, with the odds of observing a wolf being four times more likely when wolves were in the predicted viewshed. Openness was the next most influential covariate, and group size was the least influential. We also tested whether a wolf being harvested from a pack when they were outside of Yellowstone National Park had an effect on wolf sightability. We did not, however, find support for human‐induced mortality affecting wolf sightability inside of Yellowstone National Park. Our results indicate that the ability to observe wolves was greatly affected by ecological and landscape‐level factors, a finding that is likely to generally extend to other large carnivores. As such, our sightability model highlights the importance of considering landscape structure and variation in large carnivore use of the landscape when conducting observational‐based studies.

中文翻译：

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观察研究中发现不完美的原因：在黄石国家公园模拟狼的可见性

不完善的检测在野生动植物研究中无处不在，因此通常包含在丰度估算中。但是，对于稀有和难以捉摸的物种（例如大型食肉动物）而言，影响观察成功的因素很大程度上未知。在这里，我们利用了深入的地面监测工作和广泛的GPS数据集（2000-2018年），并开发了灰狼（Canis lupus）的冬季可见性模型）在美国怀俄明州的黄石国家公园北部。我们得出的可见性模型表明，观察成功与否取决于狼与观察者位置（视域），森林较少（开阔度）和狼群大小有关的地形性质，而与观察者位置的距离则具有负面影响。其中，视域对观察狼的可能性影响最大，当狼处于预测视域中时，观察狼的几率是四倍。开放性是第二大影响力的协变量，而小组规模的影响最小。我们还测试了在黄石国家公园外从狼群中收获的狼是否对狼的可见性有影响。但是，我们没有 在黄石国家公园内寻找人为导致影响狼可见性的死亡率。我们的结果表明，观察狼的能力受到生态和景观水平因素的极大影响，这一发现通常可能会扩展到其他大型食肉动物。因此，我们的可见性模型强调了在进行基于观测的研究时，在大型食肉动物使用景观时要考虑景观结构和变化的重要性。