Coupling isotope values of feathers and satellite tracking of individuals have the potential to reveal multi-season linkages between wintering habitat, diet and carry-over effects on reproductive parameters in migrating birds. Snowy owls Bubo scandiacus have multiple wintering tactics as they can use both terrestrial and marine resources during the non-breeding season, but their nomadic behaviour complicates their study. We assessed if inter-individual variability in the diet inferred by feather isotopes could be explained by habitat use in winter as determined by satellite telemetry and examined possible carry-over effects on reproduction. Seventeen breeding female snowy owls were equipped with satellite transmitters and sampled for stable isotopes (δ 13C and δ 15N) in feathers. We found a positive relationship between the use of the coastal and marine environments in winter and the contribution of marine resources to the diet of snowy owls in the previous year based on feather analysis. The proportion of marine contribution to the winter diet was variable among individuals and showed a weak negative relationship to summer body mass but not with laying date or clutch size. Our integrated approach shows the usefulness of isotope analyses to infer habitat use and expand the temporal coverage of radio-tracking studies.

中文翻译：

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使用卫星跟踪和稳定同位素分析将雪鸮的冬季栖息地利用、饮食和繁殖联系起来

将羽毛的同位素值与个体的卫星跟踪结合起来，有可能揭示越冬栖息地、饮食和对迁徙鸟类生殖参数的遗留影响之间的多季节联系。雪鸮 Bubo scandiacus 有多种越冬策略，因为它们可以在非繁殖季节利用陆地和海洋资源，但它们的游牧行为使他们的研究复杂化。我们评估了羽毛同位素推断的饮食中的个体差异是否可以通过卫星遥测确定的冬季栖息地使用来解释，并检查了可能对繁殖产生的遗留影响。17 只繁殖的雌性雪鸮配备了卫星发射器，并对羽毛中的稳定同位素（δ 13C 和 δ 15N）进行采样。基于羽毛分析，我们发现冬季沿海和海洋环境的利用与上一年海洋资源对雪鸮的饮食贡献呈正相关。海洋对冬季饮食的贡献比例因人而异，与夏季体重呈弱负相关，但与产蛋日期或离合器大小无关。我们的综合方法显示了同位素分析在推断栖息地使用和扩大无线电跟踪研究的时间覆盖范围方面的有用性。海洋对冬季饮食的贡献比例因人而异，与夏季体重呈弱负相关，但与产蛋日期或离合器大小无关。我们的综合方法显示了同位素分析在推断栖息地使用和扩大无线电跟踪研究的时间覆盖范围方面的有用性。海洋对冬季饮食的贡献比例因人而异，与夏季体重呈弱负相关，但与产蛋日期或离合器大小无关。我们的综合方法显示了同位素分析在推断栖息地使用和扩大无线电跟踪研究的时间覆盖范围方面的有用性。