Boom and bust: The effects of masting on seed predator range dynamics and trophic cascades

Aim: Spatiotemporal variation in resource availability is a strong driver of animal distributions. In northern hardwood and boreal forests of the northeastern United States, tree mast events provide resource pulses that drive the population dynamics of small mammals, including the American red squirrel (Tamiasciurus hudsonicus), a primary songbird nest predator. This study sought to determine whether mast availability ameliorates their abiotic limits, enabling red squirrel elevational distributions to temporarily expand and negatively impact high elevation songbirds. Location: Northeastern United States Methods: We used two independent datasets to evaluate our hypotheses. First, we fit a dynamic occupancy model using data from camera trap surveys to evaluate red squirrel distributional responses to pulses in tree mast. We also assessed population responses using systematic auditory surveys analyzed with an open-population binomial mixture model. Further, we used modeled red squirrel abu..., , , # Data from:Â Boom and bust: The effects of masting on seed predator range dynamics and trophic cascades ## Occupancy data **Occupancy_Cameras_RESQ.rds** - .rds file containing all associated data to run the occupancy model. ### Description of data **occ**: A three dimensional array [sites, weeks, months] with binary occurrence data of American red squirrels **nTraps**: The total number of camera traps **nWeeks**: The maximum number of weeks in a primary period (months) **nMonths**: The number of primary periods (month) **camera**: Integer for camera **wkmon**: The number of weeks within in primary period **mon_sampled**: Array [sites,start:end] with start and end month for each camera **ncovs**: number of covariates **npcovs**: number of detection covariates **nintcovs**: number of intercepts **nTrapsOp**: number of traps operating in each primary period **TrapsOp**: array with a vector of trap numbers operating **date**: centered date for week **date2**: centered date^2 for week **...研究目标：资源可利用性的时空变化是驱动动物分布的核心驱动因子。在美国东北部的北部硬木林与北方针叶林（boreal forests）中，林木种子结实大年事件会产生资源脉冲，进而调控小型哺乳动物的种群动态，其中包括美洲红松鼠（*Tamiasciurus hudsonicus*）——一类主要的鸣禽巢捕食者。本研究旨在探明结实大年的资源可利用性是否能够缓解美洲红松鼠的非生物限制条件，使其海拔分布范围发生暂时性扩张，并对高海拔鸣禽种群产生负面影响。 研究地点：美国东北部 研究方法：本研究采用两套独立数据集对研究假说进行验证。其一，利用相机陷阱（camera trap）调查数据构建动态占据模型（dynamic occupancy model），以评估美洲红松鼠的分布对林木种子结实大年脉冲的响应；其二，采用开放种群二项混合模型（open-population binomial mixture model）分析系统性声学调查数据，以此评估其种群响应。此外，本研究还使用了建模得到的美洲红松鼠丰度…… # 数据来源：《繁荣与萧条：结实大年对种子捕食者种群动态及营养级联效应的影响》 ## 占用数据 **Occupancy_Cameras_RESQ.rds**——该.rds文件包含运行占据模型所需的全部关联数据。 ### 数据说明 **occ**：三维数组[样点、周、月]，存储美洲红松鼠的二元出现数据。 **nTraps**：相机陷阱总数量 **nWeeks**：每个主周期（月）内的最大周数 **nMonths**：主周期（月）的总数 **camera**：相机的整数编号 **wkmon**：主周期内的周数 **mon_sampled**：数组[样点、起始:结束]，存储每台相机的采样起止月份 **ncovs**：协变量总数 **npcovs**：检测协变量总数 **nintcovs**：截距项总数 **nTrapsOp**：每个主周期内运行的陷阱数量 **TrapsOp**：存储各主周期运行陷阱编号的数组 **date**：周的中心化日期 **date2**：周的中心化日期平方 ……