The truth about cats and dogs: assessment of apex- and mesopredator diets improves with reduced observer uncertainty
The truth about cats and dogs: assessment of apex- and mesopredator diets improves with reduced observer uncertainty
复制标题
关于猫和狗的真相：随着观察者不确定性的减少，对顶级和中级捕食者饮食的评估得到改善
DOI：
10.1093/jmammal/gyz040
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发表时间：
2019
影响因子：
1.7
通讯作者：
E. Ritchie
中科院分区：
文献类型：
--
作者：
M. Wysong;A. Tulloch;L. Valentine;R. Hobbs;K. Morris;E. Ritchie
食物(SCAT)分析是评估捕食者对猎物的潜在影响以及比较捕食者之间的资源利用的关键工具，这些信息对于有效的野生动物管理至关重要。然而，对SCAT起源物种的错误识别可能导致关于捕食者-猎物相互作用及其对生态系统的后果的不准确结论，这最终可能危及养护和管理行动。为了解决这个问题，我们开发了一个框架，通过结合现场、实验室和分子鉴定技术，在面临不确定的SCAT物种起源的情况下进行决策。我们使用该框架从澳大利亚干旱地带的696只野外采集的海豚中检查了两种捕食者的食物，一种是本土的顶端捕食者(野狗，犬狼疮)，另一种是入侵的中掠食者(野猫，猫科动物)。我们研究了有关SCAT物种起源的不确定性如何改变了人们对共存的捕食者和猎物之间关系性质的看法。野狗和猫科动物之间的饮食重叠程度因用于识别SCAT物种来源的方法而有所不同。通过实验室鉴定评估的饮食重叠是通过我们的决策框架解决SCAT物种起源的不确定性时的两倍。如果饮食研究不能解决SCAT物种来源的不确定性，依赖这些信息的从业者和决策者可能会对捕食者的生态功能(包括对受威胁物种的潜在影响)做出错误的结论，如果针对错误的捕食者进行管理，可能会产生相反的结果。随着我们的决策框架解决了SCAT物种起源的不确定性，这两种捕食者之间的食物重叠程度很低，而且最有可能灭绝的中型哺乳动物被证明比野狗更容易受到野猫的影响。
Dietary (scat) analysis is a key tool for assessing the potential effects of predators on prey and for comparing resource use between predators, information that is crucial for effective wildlife management. However, misidentification of the species from which scats originate could result in inaccurate conclusions regarding predator–prey interactions and their consequences for ecosystems, which may ultimately compromise conservation and management actions. To address this issue, we developed a framework for decision-making in the face of uncertain scat species origin by incorporating field, laboratory, and molecular identification techniques. We used the framework to examine the diets of two predators, a native apex predator (dingo, Canis lupus dingo) and an invasive mesopredator (feral cat, Felis catus), from 696 field-collected scats in the arid zone of Australia. We examined how uncertainty regarding scat species origin changed perceptions of the nature of the relationship between coexisting predators and their prey. The extent of dietary overlap between dingoes and cats varied with the method used to identify scat species origin. Dietary overlap assessed by laboratory identifications was twice as high as when uncertainty in scat species origin was resolved through our decision framework. If uncertainty in scat species origin is not resolved in dietary studies, practitioners and decision-makers relying on this information run the risk of making misinformed conclusions regarding the ecological function of predators (including potential impacts on threatened species), which could have perverse outcomes if the wrong predators are targeted for management. With uncertainty in scat species origin resolved through our decision framework, a low level of dietary overlap between the two predators was demonstrated, and medium-sized mammals most threatened with extinction were shown to be more at risk of impact from feral cat than from dingo depredations.