Data from: Detection dog efficacy for collecting fecal samples from the critically endangered Cross River gorilla (Gorilla gorilla diehli) for genetic censusing

Population estimates using genetic capture–recapture methods from non-invasively collected wildlife samples are more accurate and precise than those obtained from traditional methods when detection and resampling rates are high. Recently, detection dogs have been increasingly used to find elusive species and their by-products. Here we compared the effectiveness of dog- and human-directed searches for Cross River gorilla (Gorilla gorilla diehli) faeces at two sites. The critically endangered Cross River gorilla inhabits a region of high biodiversity and endemism on the border between Nigeria and Cameroon. The rugged highland terrain and their cryptic behaviour make them difficult to study and a precise population size for the subspecies is still lacking. Dog-directed surveys located more fresh faeces with less bias than human-directed survey teams. This produced a more reliable population estimate, although of modest precision given the small scale of this pilot study. Unfortunately, the considerable costs associated with use of the United States-based detection dog teams make the use of these teams financially unfeasible for a larger, more comprehensive survey. To realize the full potential of dog-directed surveys and increase cost-effectiveness, we recommend basing dog-detection teams in the countries where they will operate and expanding the targets the dogs are trained to detect.利用非侵入式采集的野生动物样本开展遗传捕获重捕法（genetic capture–recapture）进行种群数量估算，在检测率与重捕率较高的前提下，其估算结果的准确度与精度均优于传统方法所得结果。近年来，探测犬（detection dog）愈发广泛地被用于搜寻珍稀物种及其排泄物等副产物。本研究在两处采样点开展对比实验，评估了探测犬引导搜寻与人工搜寻克罗斯河大猩猩（Cross River gorilla，Gorilla gorilla diehli）粪便的效果差异。处于极危状态的克罗斯河大猩猩栖息于尼日利亚与喀麦隆边境的高生物多样性、高特有性区域。崎岖的高原地形与该物种隐秘的栖息习性，使得其研究难度极大，目前该亚种仍缺乏精确的种群规模估算数据。相较于人工搜寻团队，探测犬引导的调查能够定位到更多新鲜粪便，且调查偏差更低。尽管受本次预实验的样本规模限制，估算精度较为有限，但该方法得到的种群数量估算结果更为可靠。遗憾的是，聘用总部位于美国的探测犬团队的相关成本高昂，若要开展更大规模、更全面的调查，这类团队的使用方案在经济上并不可行。为充分发挥探测犬引导调查的全部潜力并提升成本效益，我们建议将探测犬团队部署至其作业所在的国家，并拓展犬只训练时的探测目标范围。