Greenland Peregrine Falcon eggshell thickness monitoring data 1972 - 2019

The Peregrine Falcon (Falco peregrinus tundrius) population in Greenland has been monitored in different survey areas in South and West Greenland since 1972. At visits to Peregrine Falcon nests, eggshell fragments from hatched eggs as well as addled (dead) eggs left behind have been collected with the aim of monitoring the thickness of the eggshells as well as analysing the whole eggs for contaminants. The shell thickness serves as a proxy for the falcons’ exposure to certain persistant organic pollutants, in particular DDT and its breakdown products (see summaries in Cade et al. 1988). This data set contains the raw data on 6665 eggshell thickness measurements of:<br> 1. Whole eggs from South Greenland 1986-2015<br> 2. Eggshell fragments from the study area in South Greenland 1981-2019<br> 3. Eggshell fragments from the study area around Kangerlussuaq in West Greenland 1972-1989 The data set contains a mix of measurements of shell thickness including or excluding the eggshell membranes from the same clutch of eggs. Based on those measurements the average membrane thickness is 0.071 mm (SD=0.013) – a figure confirmed by other studies – and this ’membrane factor’ can be added or subtracted for comparisons with other data sets. Further details regarding the sampling areas, measurement methods and the results of trends analyses of changes in shell thickness are provided in Falk et al. (2006 and 2018). The file named <em>1_Data_Eggshell_Thickness_1972-2019.csv</em> contains the raw measurements data and the file <em>2_ReadMe_Eggshell_Thickness_1972-2019.txt</em> specifies the content. The file named <em>3_Rscript_Eggshell_Thickness_1972-2019.R</em> provides an R script for summarizing and plotting the data as shown in the file <em>4_Plot_Eggshell_Thickness_1972-2019.pdf</em>自1972年起，研究团队便在格陵兰南部与西部的多个调查区域，对游隼（Falco peregrinus tundrius）种群开展长期监测。在走访游隼巢穴的过程中，研究人员会采集已孵化卵的蛋壳碎片以及遗留的未孵化（死亡）卵，旨在监测蛋壳厚度，并对完整卵开展污染物分析。蛋壳厚度可作为游隼接触特定持久性有机污染物（尤其是滴滴涕（DDT）及其降解产物）的替代指标，相关综述详见Cade等1988年的研究成果。本数据集包含6665条蛋壳厚度测量原始数据，涵盖以下三类样本： 1. 1986—2015年采自格陵兰南部的完整卵样本 2. 1981—2019年采自格陵兰南部研究区域的蛋壳碎片样本 3. 1972—1989年采自格陵兰西部康格鲁苏阿克（Kangerlussuaq）周边研究区域的蛋壳碎片样本 数据集中混合了同一窝卵的蛋壳厚度测量值，部分测量包含蛋壳膜，部分则未包含。基于上述测量数据，研究人员测算得到蛋壳膜平均厚度为0.071 mm（标准差（SD）=0.013），该数值已得到其他独立研究的验证；该“膜校正因子”可用于与其他数据集进行比较时的加减修正。 关于采样区域、测量方法以及蛋壳厚度变化趋势分析的更多细节，详见Falk等2006年与2018年的研究成果。 名为`1_Data_Eggshell_Thickness_1972-2019.csv`的文件存储了全部原始测量数据；名为`2_ReadMe_Eggshell_Thickness_1972-2019.txt`的文件对数据集内容进行了详细说明。名为`3_Rscript_Eggshell_Thickness_1972-2019.R`的文件提供了用于汇总与可视化该数据集的R脚本，对应的可视化结果可参见`4_Plot_Eggshell_Thickness_1972-2019.pdf`。