δ13C and δ15N stable isotope compositions of the whisker of 8 harbour seals (Phoca vitulina) and 10 grey seals (Halichoerus grypus) captured in the baie de Somme, France, in 2008 and 2012, for telemetry tracking

δ13C and δ15N stable isotopes values were measured along the whiskers of eight harbour seals (Phoca vitulina) and ten grey seals (Halichoerus grypus) captured in the baie de Somme, France, in 2008 and 2012, respectively, to be fitted with FastlocTM GPS/GSM tags (cf GPS data available on http://seamap.env.duke.edu/dataset/2030 for harbour seals and on http://seamap.env.duke.edu/dataset/2026 for grey seals seals). The foraging areas posterior to seal captures are available for all harbour seals and seven on ten grey seals (Planque et al. 2020, https://doi.org/10.1007/s00227-019-3636-8). Seal whiskers provided a temporal integration of isotope compositions during the period of whisker growth, i.e. during months prior to sampling. All whisker segments were analysed with an elemental analyser (Flash 2000, Thermo Scientific, Milan, Italy) coupled to an isotope-ratio mass spectrometer (Delta V Plus with a Conflo IV interface, Thermo Scientific, Bremen, Germany). Isotope compositions are expressed with the usual δ notation in parts per thousands (‰) relative to Vienna PeeDee Belemnite Standard for δ13C and atmospheric N2 for δ15N. Based on replicate measurements of internal laboratory standards, analytical precision is < 0.15 ‰ for both δ13C and δ15N.

本数据集对2008年与2012年分别于法国索姆湾（baie de Somme）捕获的8头港海豹（Phoca vitulina）及10头灰海豹（Halichoerus grypus）的触须分段测定了碳稳定同位素比值δ¹³C与氮稳定同位素比值δ¹⁵N；所有个体均佩戴了Fastloc™ GPS/GSM追踪标签（FastlocTM GPS/GSM tags），港海豹的GPS追踪数据可参见http://seamap.env.duke.edu/dataset/2030，灰海豹的GPS追踪数据可参见http://seamap.env.duke.edu/dataset/2026。所有港海豹以及10头灰海豹中的7头均已公开其捕获后的觅食区域数据（Planque et al. 2020, https://doi.org/10.1007/s00227-019-3636-8）。海豹触须可整合触须生长周期内（即采样前数月）的同位素组成信息，所有触须片段均采用元素分析仪（Flash 2000型，赛默飞世尔科技（Thermo Scientific），意大利米兰）与同位素比值质谱仪（搭载Conflo IV接口的Delta V Plus型，赛默飞世尔科技（Thermo Scientific），德国不来梅）联用完成分析。同位素组成以常规δ符号表示，单位为千分比（‰）；其中δ¹³C以维也纳佩迪德箭石标准（Vienna PeeDee Belemnite Standard, VPDB）为参考物质，δ¹⁵N以大气氮（atmospheric N₂）为参考物质。基于实验室内部标准物质的平行测量结果，δ¹³C与δ¹⁵N的分析精度均小于0.15‰。