Data for: Four decades of phenology in an alpine amphibian: trends, stasis, and climatic drivers

This dataset is used for the analysis of the breeding phenology of a common toad (Bufo bufo) alpine population, and how it is associated with either climatic conditions or the genetics of the population. Toad Data Since 1982, we have captured annually all the toads that come to breed at the study pond. We then marked (first by toe-clipping, then starting in 1993 by implanting PIT tags), measured, and released them in the same place (Hemelaar, 1988; Grossenbacher, 2002). To make sure we captured both early and late arrivers, we repeated this procedure for on average 5–6 nights, with breaks in-between of about 2-4 days (i.e, the data conform to Pollock’s (1982) robust design). The length of the field work period usually covers the breeding season duration, which typically lasts about two weeks at our study pond. This design also had the advantage of not overly stressing the toads. In total, for the period 1982–2020, 3053 uniquely recognizable individuals have been caught, of which 1852 were males and 1201 females. For each individual we have a record of presence for each capture night over the study period. Given the reduced size of the pond and the repeated capture rounds within a capture night, we assumed high capture probabilities (capture probability p ≈ 0.85 per year based on a preliminary analysis of the mark-recapture data). At the population level we determined for each year a start, a peak, and an end date of breeding (i.e., first capture night, the capture night when most toads were captured, and last capture night, respectively). These calendar dates were all transformed into days of the year (where January 1st is 1), to facilitate modelling of long-term trends. Weather Data We obtained climatic data for the period 1980–2020 from the DaymetCH dataset (data obtained from Bioclimatic maps of Switzerland © WSL, based on station data from the Federal Office of Meteorology and Climatology MeteoSwiss, and elaborated by the Land Change Science group, WSL). This dataset consists of a 100-metre resolution grid of interpolated estimates of weather variables, using meteorological data from ground stations and the Daymet software (Thornton et al., 1997). We obtained data for the cell containing the breeding pond for the following variables: daily minimum, maximum, and mean temperature, daily total precipitation, and daily snow water equivalent (SWE; the equivalent amount of water stored in the snow pack). We then calculated average seasonal minimum daily temperatures (winter and spring), and cumulative seasonal precipitation (spring) and SWE (winter and spring). The csv file Season_values store these measures (one value for each of the 5 climatic variables per year, for the period 1982-2020, as the study on the toads started in 1982). We conducted all the analyses in R (R version 4.1.1; R Core Team, 2020) with RStudio (version 2022.7.1.554; R Studio Team, 2022).本数据集用于分析普通蟾蜍（Bufo bufo）高山种群的繁殖物候，及其与气候条件或种群遗传学的关联。 蟾蜍数据 1982年起，研究团队每年对到访研究池塘繁殖的所有蟾蜍开展捕获工作。随后对其进行标记（最初采用剪趾法，1993年起改用植入PIT标签（PIT tag））、测量，并原地放归（Hemelaar, 1988; Grossenbacher, 2002）。为确保捕获到早到达与晚到达的个体，本研究平均重复开展5~6晚的捕获流程，每晚间隔约2~4天，即数据符合Pollock（1982）提出的稳健设计。野外工作周期通常覆盖完整繁殖季，研究池塘的繁殖季时长约为两周。该设计还可避免对蟾蜍造成过度应激。1982-2020年期间，总计捕获3053只可唯一识别的个体，其中雄性1852只，雌性1201只。针对每只个体，我们记录了其在研究期内各捕获夜的出现情况。鉴于池塘面积有限且单晚内开展多次捕获轮次，我们推测年捕获概率较高（基于标记重捕数据的初步分析，年捕获概率p ≈ 0.85）。在种群水平上，我们每年确定繁殖的起始、峰值与结束日期，分别对应首次捕获夜、捕获蟾蜍数量最多的捕获夜以及末次捕获夜。所有日历日期均转换为年中日（1月1日记为1），以方便长期趋势建模。 气候数据 我们从DaymetCH数据集获取了1980-2020年的气候数据，数据源自瑞士生物气候地图© WSL，基于瑞士联邦气象与气候办公室（MeteoSwiss）的台站数据，由WSL土地变化科学组整理。该数据集为分辨率100米的栅格数据，通过地面站气象数据与Daymet软件（Thornton等，1997）插值得到各气象变量的估算值。我们提取了包含研究池塘的栅格单元的数据，涉及以下变量：每日最低、最高与平均气温，日总降水量，以及每日雪水当量（SWE；积雪中储存的等效水量）。随后我们计算了各季节的平均最低日气温（冬季与春季），以及累计季节降水量（春季）和累计季节雪水当量（冬季与春季）。名为Season_values的CSV文件存储了这些指标，1982-2020年每年对应5个气候变量各1个值，因蟾蜍研究始于1982年。 所有分析均在R（版本4.1.1；R开发核心团队，2020）与RStudio（版本2022.7.1.554；RStudio开发团队，2022）中完成。