Animal abundance and diversity in coastal grasslands

Meta dataMethodsManagement history of Rancho Marino and Fiscalini Ranch were investigated by observing tilled/planted and untilled/unplanted grasslands. Two 100 m transects at each site were utilized. The coordinates of the transects are as follows: Fiscalini Ranch (transect 1 start: [N35.54944, E121.10043], stop: [N35.55009, E121.10102]), (transect 2 start [N35.55046, E121.10166], stop [N35.5517, E121.10227]) and Rancho Marino (transect 1 start [N35.53966, E121.09032], stop [N35.53896, E121.08968]), (transect 2 start [N35.52933, E121.07793], stop [N35.52862, E121.07728]). Each transect consisted of eight plots where animal cameras were deployed over the course of three nights. The plots on each transect were chosen by randomization of 25 numbers ranging from 1 to 100. Eight of these numbers were again randomly selected for each of the three nights. No two plots were repeated. From the transect line, the 0.5 m x 0.5 m quadrat was placed down at a distance of 3 m to avoid interference with other sampling plots. Percent coverage of Phalaris aquatica, invasive grasses, and bare ground was measured by estimation. A motion triggered animal camera was placed on the bottom right corner of the quadrat facing North. Plants obstructing the camera’s field of view were subsequently removed. The bait, consisting of peanut butter and oats, was placed 1 m away from the camera on a white paper plate and weighed down with a stone. Cameras were deployed at 4:00 PM and footage was collected from 5:00 PM to 9:00 AM. The following day, the SD cards were taken from each camera and were analyzed for the presence of animal activity. The pictures were organized based on site, transect, day, and camera. A positive hit was defined as animal presence in the capture frame. Two or more animals of the same species were considered independent positive hits if they were seen an hour apart. Total abundance and diversity of animals were counted and recorded for each location. All data was collected and recorded for further analysis of results.VariablesSite: RM is Rancho Marino and FR is Fiscalini RanchManagement History: If the land was planted with Phalaris aquatica/tilled or remained unplanted/untilled. Transect: Distinguishes the two distinct lines in each site that were selected for sampling. Each transect within each site has it’s own coordinates. Rep.day: The day that cameras were deployed Rep.cam: The number of cameras deployed per transect each nightHarding cover: Coverage of Phalaris aquatica measured as a percentage of the quadrat Exotic plant cover: Coverage of other exotic plant species measured as a percentage of the quadrat Bare cover: Coverage of bare ground measured as a percentage of the quadratAnimal sign: Evidence of animal activity noted near the quadrat such as scatt and burrowing. 1 indicates sign of animal while 0 indicates an absence Taxa: Specific taxa captured by cameraMethod: Motion triggered animal cameras were used to calculate abundance and diversity of animals Abundance: Total number of individual animals seen during footage time (a collective sum of all 8 cameras used per night) Diversity: Total number of different animal species Sample time: Total hours of footage collected between 5:00 PM and 9:00 AMRate: Number of positive hits/hour *Authors are all equal contributors listed in alphabetical order

本研究通过对比翻耕/种植与未翻耕/未种植的草地，对兰乔马里诺（Rancho Marino）和菲斯卡里尼牧场（Fiscalini Ranch）的管理历史展开调查。每个样地设置两条100米长的样带（transect），样带坐标如下：菲斯卡里尼牧场样带1：起点[N35.54944, E121.10043]，终点[N35.55009, E121.10102]；样带2：起点[N35.55046, E121.10166]，终点[N35.5517, E121.10227]。兰乔马里诺样带1：起点[N35.53966, E121.09032]，终点[N35.53896, E121.08968]；样带2：起点[N35.52933, E121.07793]，终点[N35.52862, E121.07728]。每条样带设置8个样方（quadrat），连续三个夜间布设运动触发动物相机（motion triggered animal camera）。样方的初始选取通过对1至100的25个数字进行随机抽样确定，随后每晚再从这25个数字中随机抽取8个作为当晚的采样样方，确保样方不重复布设。从样带线向外3米处布设0.5m×0.5m的样方，以避免与其他采样样方产生干扰。通过估测法记录球茎虉草（Phalaris aquatica）、入侵草本植物以及裸地的盖度百分比。将运动触发动物相机（motion triggered animal camera）放置于样方右下角，朝向正北，并移除遮挡相机视场的植物。在相机1米外的白色纸盘上放置由花生酱与燕麦组成的诱饵，并用石块固定以防止移动。相机于当日下午4:00完成部署，采集时段为当日下午5:00至次日上午9:00。次日回收各相机的SD存储卡，分析其中的动物活动影像。将拍摄的影像按样地、样带、日期及相机编号进行整理。阳性记录的判定标准为：捕获帧中出现动物个体；同一物种的两只及以上动物若间隔1小时及以上被拍摄到，则视为独立的阳性记录。统计并记录各采样点的动物总丰度与物种多样性。所有数据均已完成收集与记录，用于后续的结果分析。

变量说明：
样地（Site）：RM为兰乔马里诺（Rancho Marino），FR为菲斯卡里尼牧场（Fiscalini Ranch）
管理历史（Management History）：记录样地是否种植过球茎虉草（Phalaris aquatica）并经过翻耕，或处于未种植、未翻耕的状态
样带（Transect）：用于区分每个样地内两条独立的采样样带，每个样地内的每条样带均配有专属坐标
采样日期（Rep.day）：相机部署的日期
夜间部署相机数（Rep.cam）：每个样带每晚部署的相机数量
Harding盖度（Harding cover）：以样方百分比计量的球茎虉草（Phalaris aquatica）盖度
外来植物盖度（Exotic plant cover）：以样方百分比计量的其他外来植物物种盖度
裸地盖度（Bare cover）：以样方百分比计量的裸地盖度
动物活动痕迹（Animal sign）：样方周边记录的动物活动证据，如粪便、洞穴等。赋值1代表存在动物活动痕迹，赋值0代表无痕迹
动物类群（Taxa）：相机捕获的具体动物类群
调查方法（Method）：采用运动触发动物相机（motion triggered animal camera）统计动物丰度与物种多样性
动物丰度（Abundance）：单晚所有8台相机拍摄时段内记录到的动物个体总数
物种多样性（Diversity）：记录到的不同动物物种总数
采样时长（Sample time）：当日下午5:00至次日上午9:00的总拍摄时长
检出率（Rate）：每小时阳性记录数，即阳性记录数与总采样时长的比值

* 所有作者贡献均等，按字母顺序排列