Abstract:
Stoat (Mustela erminea) and weasel (M. nivalis) are hard to monitor as they are elusive of nature and leave few identifying marks in their surroundings. Stoat and weasel are both fully protected in Denmark and are thought to be widely distributed throughout the country. Despite this stoat and weasel were listed on the Danish Red List as Near Threatened in 2019, as their densities and population trends are unknown. Using a modified novel camera trapping device, the Double-Mostela, a wooden box comprising a tracking tunnel and two camera traps, we attempted to obtain density estimates based on identification of individual stoats and weasels. We deployed camera traps both inside Double-Mostela traps and externally in three different study areas in northern Zealand, Denmark, and tested commercial, American scent-based lures to attract stoat and weasel. We obtained very low seasonal trapping rates of weasel in two study areas, but in one study area, we obtained a seasonal trapping rate of stoat larger compared to another study using the Mostela. In one study area, both species were absent. We observed no effect of scent-based lures in attracting small mustelids compared to non-bait traps. Potential reasons behind low capture rates of weasel and stoat are suboptimal habitat placement and timing of deployment of the Double-Mostelas, land-use changes over the last 200 years, predation from larger predators, as well as unintended secondary poisoning with rodenticides. Due to the scarcity of weasel and stoat captures, we were unable to make density estimates based on identification of individuals; however, we identified potential features that could be used for identification and density estimates with more captures.
摘要:
斯托特(Mustelaerminea)和黄鼠狼(M.nivalis)很难监控,因为它们对自然难以捉摸,并且在周围环境中几乎没有识别标记。斯帕特和黄鼠狼在丹麦都受到充分保护,并被认为在全国范围内广泛分布。尽管这种长发和黄鼠狼在2019年被列入丹麦红色名录,但它们的密度和人口趋势尚不清楚。使用改良的新型相机诱捕装置,双Mostela,一个木箱,包括一个跟踪隧道和两个相机陷阱,我们试图根据个体白鼠和黄鼠狼的识别获得密度估计。我们在Double-Mostela陷阱内部和外部在新西兰北部三个不同的研究区域部署了相机陷阱,丹麦,并经过商业测试,美国基于气味的诱饵吸引白鼠和黄鼠狼。我们在两个研究区域获得了很低的黄鼠狼季节性捕获率,但是在一个研究领域,与使用Mostela的另一项研究相比,我们获得的季节性诱捕率更大。在一个研究区域,两个物种都不存在。与非诱饵诱捕器相比,我们没有观察到基于气味的诱饵在吸引小芥菜方面的作用。黄鼠狼和长尾鼠捕获率低的潜在原因是栖息地的位置和部署Double-Mostelas的时机欠佳,过去200年的土地利用变化,来自更大的捕食者的捕食,以及杀鼠剂的意外二次中毒。由于黄鼠狼和猎鹰的稀缺性,我们无法根据个人身份进行密度估计;然而,我们确定了可用于识别和密度估计的潜在特征,同时捕获更多.