Escape behaviour in Estonian birds: differences in flight initiation distance (FID) between urban and rural populations

This data contains 2129 observations of escape behaviour from 57 bird species from Estonian urban and rural habitats. Data was collected in 2015-2016 by Kunter Tätte. Flight initiation distances are accompanied by starting distances, alert distances and various other covariates. This data contains observations from four studies (but not observations collected by other authors): 1) Samia, D.S.M., Blumstein, D.T., Díaz, M., Grim, T., Ibáñez-Álamo, J.D., Jokimäki, J., Tätte, K., Markó, G., Tryjanowski, P., Møller, A.P. (2017). Rural-Urban Differences in Escape Behavior of European Birds Across a Latitudinal Gradient. Frontiers in Ecology and Evolution, 5: 66. 2) Tätte, K., Møller, A.P., Mänd, R. (2018). Towards an integrated view of escape decisions in birds: relation between flight initiation distance and distance fled. Animal Behaviour, 136: 75-86. 3) Morelli, F., Benedetti, Y., Díaz, M., Grim, T., Ibáñez-Álamo, J., Jokimaki, J., Kaisanlahti-Jokimäki, M.L., Tätte, K., Marko, G., Jiang, Y., Tryjanowski, P., Møller, A.P. (2018). Contagious fear: Escape behavior increases with flock size in European gregarious birds. Ecology and Evolution, 9(10), 6096-6104. 4) Unpublished data. Mainly for a discontinued project titled "Effects of winter weather and latitude on escape decisions" in 2015 by Anders Pape Møller. There is also excluded data from the first three studies (i.e. either species with too few observations, or species not of interest in a particular study, or repeat observations) Some remarks: * All distances are in meters, but snow cover in cm * Temperatures are in celsius. * This data set is good for urban-rural comparisons because (a) I always collected observations from both habitats on the same day, (b) starting distances between urban and rural habitats are very similar, (c) there is a large overlap between species composition * Most birds were located on the ground (initial_perch_height = 0) * Whenever a column name has "repeat_..." as prefix, it indicates a second subsequent approach to the same individual. After the first approach I moved back to a starting distance of about 30 m and then recorded alert distance and FID again. This repeat data has not been analyzed or used anywhere. * In the column titled sex, M=male, F=female. I am not very certain about how well I was able to sex Motacilla alba, but observations from other species should be fine. Sex data has not been analyzed. * approach_speed "normal" indicates a walking speed of 1.3 m/s, while "fast" was about 2.6 m/s. However, note that some observations were made during wintertime with snow, meaning that the approach speeds might have been slower then. I would treat winter data with caution. There is also a column "bird_feeder_nearby" that indicates whether a bird feeder was in sight, but it does not necessarily mean that the bird was feeding there. * Column on flock size does not discriminate between same-species groups and mixed-species groups.

本数据集包含来自爱沙尼亚城市与乡村生境的57种鸟类的2129条逃逸行为观测记录。该数据由Kunter Tätte于2015至2016年间采集。数据记录了鸟类的起飞逃逸距离（flight initiation distance, FID），同时配套记录了起始距离、警戒距离以及多种其他协变量。
本数据集整合了四项研究的观测数据（但不包含其他作者采集的观测样本）：
1. Samia, D.S.M., Blumstein, D.T., Díaz, M., Grim, T., Ibáñez-Álamo, J.D., Jokimäki, J., Tätte, K., Markó, G., Tryjanowski, P., Møller, A.P. (2017). 《欧洲鸟类沿纬度梯度逃逸行为的城乡差异》，《生态学与进化前沿》(Frontiers in Ecology and Evolution), 5: 66。
2. Tätte, K., Møller, A.P., Mänd, R. (2018). 《鸟类逃逸决策的整合视角：起飞逃逸距离与逃逸飞行距离的关联》，《动物行为》(Animal Behaviour), 136: 75-86。
3. Morelli, F., Benedetti, Y., Díaz, M., Grim, T., Ibáñez-Álamo, J., Jokimaki, J., Kaisanlahti-Jokimäki, M.L., Tätte, K., Marko, G., Jiang, Y., Tryjanowski, P., Møller, A.P. (2018). 《传染性恐惧：群居鸟类的逃逸行为随种群规模增大而增强》，《生态学与进化》(Ecology and Evolution), 9(10): 6096-6104。
4. 未发表数据：主要来自Anders Pape Møller于2015年开展的一项已终止项目《冬季天气与纬度对鸟类逃逸决策的影响》。
此外，本数据集剔除了前三项研究中的部分数据（即观测样本量过少的物种、特定研究中不关注的物种，以及重复观测样本）。
相关说明如下：
* 所有距离单位均为米，但积雪覆盖度单位为厘米；温度单位为摄氏度。
* 本数据集非常适用于城乡生境的对比分析，原因在于：(a) 研究者始终在同一天完成同一物种在城乡两种生境的观测采样；(b) 城乡生境间的起始距离差异极小；(c) 物种组成存在高度重叠。
* 多数观测鸟类栖息于地面（初始栖息高度initial_perch_height = 0）。
* 若某列名称以“repeat_”为前缀，则代表针对同一个体的第二次后续逼近观测：在首次逼近完成后，研究者会后退至约30米的起始距离，再次记录警戒距离与起飞逃逸距离。该重复观测数据尚未被任何研究分析或使用。
* 性别列中，“M”代表雄性，“F”代表雌性。研究者对白鹡鸰（Motacilla alba）的性别判定准确性存疑，但其他物种的性别记录应无问题。目前性别数据尚未用于分析。
* 逼近速度列中，“normal”代表步行速度1.3 m/s，“fast”代表约2.6 m/s。但需注意，部分观测在冬季积雪环境下完成，此时逼近速度可能更慢，因此对冬季观测数据需谨慎处理。
* 数据集包含“bird_feeder_nearby”列，用于标记观测范围内是否存在鸟类喂食器，但这并不意味着鸟类正在喂食点取食。
* 种群规模列未区分同物种种群与混合物种种群。