Environmental correlates of large-scale spatial variation in the Delta13C of marine animals

Carbon stable isotopes can be used to trace the sources of energy supporting
food chains and to estimate the contribution of different sources to a
consumer's diet. However, the δ13C signature of a consumer is not sufficient
to infer source without an appropriate isotopic baseline, because there is no
way to determine if differences in consumer δ13C reflect source changes or
baseline variation. Describing isotopic baselines is a considerable challenge
when applying stable isotope techniques at large spatial scales and/or to
interconnected food chains in open marine environments. One approach is to use
filter-feeding consumers to integrate the high frequency and small-scale
variation in the isotopic signature of phytoplankton and provide a surrogate
baseline, but it can be difficult to sample a single consumer species at large
spatial scales owing to rarity and/or discontinuous distribution. Here, we use
the isotopic signature of a widely distributed filter-feeder the queen scallop
(*Aequipecten opercularis*) in the north-eastern Atlantic to develop a model
linking base δ13C to environmental variables. Data includes catch data,
isotope analysis data, environmental data and associated positional data.

碳稳定同位素可用于追踪支撑食物链的能量来源，并估算不同来源对消费者饮食的贡献。然而，消费者δ13C的特征不足以推断来源，除非有适当的同位素基线，因为无法确定消费者δ13C的差异系来源变化还是基线变异所致。在大尺度空间范围内或对开放海洋环境中的相互连接的食物链应用稳定同位素技术时，描述同位素基线是一项重大挑战。一种方法是利用滤食消费者整合浮游植物同位素特征的频繁和小尺度变异，从而提供一个替代基线，但由于稀有性和/或分布不连续，在大尺度空间范围内对单一消费者物种进行采样可能存在困难。在本研究中，我们利用分布广泛的滤食性贝类——东北大西洋的皇后扇贝（*Aequipecten opercularis*）的同位素特征，构建了一个将基础δ13C与环境变量相联系的模式。数据包括捕捞数据、同位素分析数据、环境数据和相关的位置数据。