Data from: Enhanced understanding of predator–prey relationships using molecular methods to identify predator species, individual and sex

Predator species identification is an important step in understanding predator-prey interactions, but predator identifications using kill site observations are often unreliable. We used molecular tools to analyse predator saliva, scat and hair from caribou calf kills in Newfoundland, Canada to identify the predator species, individual and sex. We sampled DNA from 32 carcasses using cotton swabs to collect predator saliva. We used fragment length analysis and sequencing of mitochondrial DNA to distinguish between coyote, black bear, Canada lynx and red fox and used nuclear DNA microsatellite analysis to identify individuals. We compared predator species detected using molecular tools to those assigned via field observations at each kill. We identified a predator species at 94% of carcasses using molecular methods, while observational methods assigned a predator species to 62.5% of kills. Molecular methods attributed 66.7% of kills to coyote and 33.3% to black bear, while observations assigned 40%, 45%, 10% and 5% to coyote, bear, lynx and fox, respectively. Individual identification was successful at 70% of kills where a predator species was identified. Only one individual was identified at each kill, but some individuals were found at multiple kills. Predator sex was predominantly male. We demonstrate the first large-scale evaluation of predator species, individual and sex identification using molecular techniques to extract DNA from swabs of wild prey carcasses. Our results indicate that kill site swabs (i) can be highly successful in identifying the predator species and individual responsible; and (ii) serve to inform and complement traditional methods.捕食者物种识别是解析捕食者-猎物相互作用的关键环节，但依托捕杀现场观测开展的捕食者识别工作往往可靠性欠佳。我们借助分子生物学工具，对加拿大纽芬兰地区驯鹿幼崽捕杀现场留存的捕食者唾液、粪样及毛发样本进行分析，以明确捕食者的物种、个体身份与性别。我们通过棉拭子采集了32具猎杀现场的猎物尸体表面的捕食者唾液，并从中提取DNA样本。我们采用片段长度分析与线粒体DNA（mitochondrial DNA）测序技术，对郊狼、美洲黑熊、加拿大猞猁与赤狐进行区分；同时借助核DNA微卫星（microsatellite）分析技术完成捕食者个体识别。我们将分子技术检测得到的捕食者物种结果，与各猎杀现场通过野外观测所指派的物种结果进行对比。通过分子方法，我们在94%的猎物尸体样本中成功识别出捕食者物种；而观测方法仅能为62.5%的猎杀现场指派捕食者物种。分子方法将66.7%的猎杀事件归因于郊狼，33.3%归因于美洲黑熊；而野外观测方法则分别将40%、45%、10%与5%的猎杀事件指派给郊狼、黑熊、猞猁与赤狐。在成功识别出捕食者物种的猎杀现场中，70%的样本实现了个体识别。每个猎杀现场仅检出一只捕食者个体，但部分个体在多个猎杀现场被重复检出。捕食者性别以雄性占绝对主导。本研究首次针对通过分子技术从野生猎物尸体拭子中提取DNA的方式，开展了大规模的捕食者物种、个体及性别识别性能评估。我们的研究结果表明，捕杀现场拭子（i）可高效识别实施猎杀的捕食者物种与个体；（ii）可用于为传统研究方法提供参考并与之形成互补。