Data belonging to the article: Estimating pre-harvest density, adult sex ratio and fecundity of white-tailed deer using wildlife cameras

Adult sex ratio and fecundity (juveniles per female) are key population parameters in sustainable wildlife management, but inferring these requires abundance estimates of at least three age/sex classes of the population (male and female adults and juveniles). Prior to harvest, we used an array of 36 wildlife camera traps during 2 and 3 weeks in the early autumn of 2016 and 2017 respectively. We recorded white-tailed deer adult males, adult females and fawns from the pictures. Simultaneously, we collected fecal DNA (fDNA) from 92 20mx20m plots placed in 23 clusters of four plots between the camera traps. We identified individuals from fDNA samples with microsatellite markers and estimated the total sex ratio and population density using Spatial Capture Recapture (SCR). The fDNA-SCR analysis concluded equal sex ratio in the first year and female bias in the second year, and no difference in space use between sexes (fawns and adults combined). Camera information was analyzed in a Spatial Capture (SC) framework assuming an informative prior for animals’ space use, either (1) as estimated by fDNA-SCR (same for all age/sex classes), (2) as assumed from the literature (space use of adult males larger than adult females and fawns), (3) by inferring adult male space use from individually-identified males from the camera pictures. These various SC approaches produced plausible inferences on fecundity, but also inferred total density to be lower than the estimate provided by fDNA-SCR in one of the study years. SC approaches where adult male and female were allowed to differ in their space use suggested the population had a female-biased adult sex ratio. In conclusion, SC approaches allowed estimating the pre-harvest population parameters of interest and provided conservative density estimates.

成年性比与繁殖力（每雌繁殖幼体数）是可持续野生动物管理中的核心种群参数，但要推算这两项指标，需获取种群至少三类年龄/性别组的丰度估计值，即成年雄性、成年雌性以及幼体。在狩猎活动开展前，我们分别于2016年和2017年的早秋时段，部署了由36台野生动物红外相机组成的监测阵列，监测时长分别为2周与3周。我们从拍摄的影像中记录了白尾鹿的成年雄性、成年雌性与幼鹿。与此同时，我们在相机阵列间布设的23个样地集群（每个集群含4块20米×20米的样方）中，共收集了92块样方的粪便DNA（fecal DNA, fDNA）样本。我们利用微卫星标记对粪便DNA样本中的个体进行识别，并通过空间捕获再捕获（Spatial Capture Recapture, SCR）模型估算了总性比与种群密度。粪便DNA-空间捕获再捕获分析结果显示，第一年种群性比均衡，第二年则表现为雌性偏倚，且雌雄（含幼体与成体）的空间利用模式无显著差异。我们采用空间捕获（Spatial Capture, SC）分析框架对相机监测数据进行处理，该框架设定了动物空间利用的信息性先验，共包含三种假设场景：（1）以粪便DNA-空间捕获再捕获模型的估算结果作为先验（所有年龄/性别组的空间利用模式一致）；（2）基于文献设定先验（成年雄性的空间活动范围大于成年雌性与幼鹿）；（3）通过相机影像中个体识别的成年雄性数据推断其空间利用模式。上述不同的空间捕获分析方法均得到了合理的繁殖力推断结果，但在其中一个研究年份中，其估算的总种群密度低于粪便DNA-空间捕获再捕获模型的结果。允许成年雄性与雌性空间利用模式存在差异的空间捕获分析方法，则推断种群成年性比呈现雌性偏倚。综上，空间捕获分析方法可有效估算目标狩猎前种群参数，并得到较为保守的种群密度估计值。