Settlement rates of fishes and crab megalopa within Artificial Seagrass Units (ASU) in Back Sound, NC from June to August 2018

To parse the ecological effects of habitat area and patchiness on faunal community structure and dynamics of estuarine nekton, we employed artificial seagrass unit (ASU) landscapes at a scale relevant to habitat fidelity of common fish and macroinvertebrates in our temperate study system, Back Sound, NC. These ASU landscapes were designed along orthogonal axes of artificial seagrass area (i.e., percent cover of each landscape = 10-60 percent) and fragmentation per se (i.e., percolation probability; 0.1-0.59) to delineate their independent and interactive effects on seagrass fish and macroinvertebrate communities. To assess whether faunal density patterns across landscapes were driven by larval settlement, larval fishes and crab megalopa were sampled seven times from June to August 2018 using Standardized Monitoring Units for the Recruitment of Fishes (SMURFs). To examine how settlement rates across landscapes differed depending upon the amount of immediately surrounding artificial seagrass, each SMURF was positioned at the 'center' of the largest ASU patch (as estimated for each irregular shape) in each landscape. SMURF samples were collected by Drs. F. Joel Fodrie and Amy H. Yarnall for the Estuarine Ecology Laboratory of the University of North Carolina at Chapel Hill’s Institute of Marine Sciences. SMURF samples were processed by Lauren A. Yeager at the Marine Science Institute, of the University of Texas at Austin.为解析栖息地面积与斑块性对河口游泳动物群落结构及动态的生态效应，我们在温带研究系统——北卡罗来纳州巴克桑德（Back Sound）中，采用与常见鱼类和大型无脊椎动物栖息地保真度相匹配的尺度下的人工海草单元（artificial seagrass unit, ASU）景观。这些人工海草单元景观沿正交轴设计，分别对应人工海草面积（即各景观的盖度百分比为10%~60%）与固有破碎化程度（即渗流概率，取值范围0.1~0.59），以厘清二者对海草生境鱼类及大型无脊椎动物群落的独立与交互效应。 为探究不同景观间的动物密度格局是否由幼体沉降所驱动，我们于2018年6月至8月期间，采用鱼类招募标准化监测单元（Standardized Monitoring Units for the Recruitment of Fishes, SMURFs）开展了7次采样，以收集幼鱼与蟹类大眼幼体。为检验不同景观下的幼体沉降速率是否随紧邻周边人工海草的丰度而变化，我们将每个SMURF放置于各景观中最大的人工海草单元斑块的“中心”位置（针对每个不规则斑块进行估算）。 本研究的SMURF样本由北卡罗来纳大学教堂山分校海洋科学研究所河口生态学实验室的F. Joel Fodrie博士与Amy H. Yarnall博士采集。SMURF样本的处理工作由德克萨斯大学奥斯汀分校海洋科学研究所的Lauren A. Yeager完成。