Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, 1432 Ås, Norway.
Norwegian Institute for Nature Research (NINA), 7485 Trondheim, Norway.
Biol Lett. 2021 Jun;17(6):20210128. doi: 10.1098/rsbl.2021.0128. Epub 2021 Jun 30.
Are instrumented animals representative of the population, given the potential bias caused by selective sampling and the influence of capture, handling and wearing bio-loggers? The answer is elusive owing to the challenges of obtaining comparable data from individuals with and without bio-loggers. Using non-invasive genetic data of a large carnivore, the wolverine () in Scandinavia, and an open-population spatial capture-recapture model, we found a 16 (credible interval: 4-30) percentage points lower mortality probability for GPS-collared individuals compared with individuals without GPS collars. While the risk of dying from legal culling was comparable for collared and non-collared wolverines, the former experienced lower probability of mortality due to causes other than legal culling. The aforementioned effect was pronounced despite a potentially lower age-and therefore likely higher natural mortality-of collared individuals. Reports of positive effects of bio-loggers on the survival of individuals are uncommon and we argue that GPS collars could shield animals from poaching. Our results highlight the challenges of drawing population-level inferences for populations subjected to poaching when using data from instrumented individuals.
鉴于选择性采样带来的潜在偏差以及捕捉、处理和佩戴生物标记物的影响，有佩戴仪器的动物是否能代表整个种群？由于难以从佩戴和未佩戴生物标记物的个体中获得可比数据，因此这个问题的答案难以确定。我们使用斯堪的纳维亚地区一种大型食肉动物——狼獾的非侵入性遗传数据和开放种群空间捕获-再捕获模型发现，与未佩戴 GPS 项圈的个体相比，佩戴 GPS 项圈的个体的死亡率概率低 16 个百分点（置信区间：4-30）。虽然佩戴和未佩戴 GPS 项圈的狼獾因合法捕猎而死亡的风险相当，但前者因合法捕猎以外的原因死亡的概率较低。尽管佩戴 GPS 项圈的个体年龄可能较低（因此自然死亡率可能较高），但上述影响仍然明显。关于生物标记物对个体生存产生积极影响的报告并不常见，我们认为 GPS 项圈可以保护动物免受偷猎。我们的研究结果强调了在使用佩戴仪器的个体的数据推断受到偷猎影响的种群时，在种群水平上进行推断所面临的挑战。
