Motion‐triggered camera traps are subject to imperfect detection and thus camera‐trapping surveys often try to increase species detectability as part of the study design. One possible way to increase detectability is to use lures, which may encourage a species to investigate a given area. Yet the effectiveness of lures is primarily grounded in anecdotal support. We quantified the effect of a common olfactory carnivore lure on the detectability of mammals near Chicago, Illinois, USA, during 27 August 2018–25 September 2018. We deployed 2 camera traps per site, spaced apart by 100 m, to assess whether lure can modify detectability both within and between sites. At each camera location, we changed lure treatments every 7 days and placed either a lure or a non‐lure control in view of each camera following a fully crossed design. For analysis, we developed single‐season occupancy models with 3 distinct observational models to quantify whether lure increased the number of days a species was detected, decreased the amount of time to first detection, and increased the number of images collected. Lure induced a subtle change in detectability. Virginia opossum (Didelphis virginiana) responded most to the presence of lure; their daily detection probability rose by roughly 5% and the number of opossum images nearly doubled. However, the effect of lure was often negative for prey species. When lure was present, eastern cottontail (Sylvilagus floridanus) daily detection probability decreased by 5% and they were photographed 63% less often. Likewise, eastern gray squirrel (Sciurus carolinensis) arrived 70% later to a camera trap if lure was present and were photographed 14% less. By using multiple criteria, we were able to better understand how wildlife respond to lure while camera‐trapping more thoroughly than would be possible with a single metric. Our results show that lure may not be as effective as expected in terms of increasing detectability, but the choice to use lure should depend on several factors, including the density of the study species, species life history, and the dynamics between the species studied. © 2020 The Wildlife Society.

中文翻译：

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诱饵对用相机陷阱检测哺乳动物的影响

触发运动的摄像机陷阱的检测不完善，因此，作为研究设计的一部分，摄像机陷阱调查通常会尝试提高物种的可探测性。提高可检测性的一种可能方法是使用诱剂，这可能会鼓励物种调查给定区域。然而，诱饵的有效性主要基于轶事支持。我们在2018年8月27日至2018年9月25日之间量化了常见的嗅觉食肉动物引诱对美国伊利诺伊州芝加哥附近的哺乳动物的可检测性的影响。我们在每个站点部署了两个摄像头，相隔100 m，以评估诱饵是否可以修改站点内部和站点之间的可检测性。在每个摄像头位置，我们每隔7天更改一次诱饵处理，并按照完全交叉的设计针对每个摄像头放置一个诱饵或一个非诱饵控件。为了分析，我们开发了具有3种不同观察模型的单季节居住模型，以量化诱饵是否增加了检测物种的天数，减少了首次检测的时间并增加了收集的图像数量。诱剂在可检测性上引起了细微的变化。弗吉尼亚负鼠（Didelphis virginiana）对诱饵的反应最大。他们的每日检测概率增加了5％，负鼠图像的数量几乎翻了一番。但是，诱饵的作用通常对猎物种类不利。当存在诱饵时，东部棉尾（（Sylvilagus floridanus）的每日检测概率降低了5％，而被拍照的频率则降低了63％。同样，东部灰松鼠（Scuulus carolinensis）在有诱饵的情况下70％之后到达了相机陷阱，并且被拍照的人数减少了14％。通过使用多个标准，我们可以更好地了解野生生物对诱饵的反应，同时比单项指标更全面地捕捉照相机。我们的结果表明，就增加可检测性而言，诱饵可能没有预期的有效，但是诱饵的选择应取决于几个因素，包括研究物种的密度，物种生活史以及研究物种之间的动力学。©2020野生动物协会。