Australian Rivers Institute - Coast and Estuaries, School of Environment and Science, Griffith University, Gold Coast, QLD 4222, Australia.
Sci Total Environ. 2020 Feb 25;705:135782. doi: 10.1016/j.scitotenv.2019.135782. Epub 2019 Nov 26.
It is helpful to understand the movement of animals and objects to inform species conservation and broader environmental management (e.g. by identifying the origin of marine debris). Tagging techniques are limited to investigations of future movement (e.g. after a tag has been applied), with no ability to understand where an animal or object has come from prior to encounter. However, studies that apply chemical techniques are able to address questions about historical movement prior to encounter, particularly through the analysis of stable isotopes from the tissues of migrating animals, or from barnacle shells that attach to migrating hosts. Barnacle shell isotope analysis is a promising technique that could provide a new understanding of the ecology of migrating marine fauna, or additionally the origin of marine debris. Here we use global datasets to assess the applicability of barnacle shell isotope techniques for identifying the origin and travel pathways of animals and objects that carry hitchhiking barnacles. We present the first global isoscapes for barnacle shell calcite, using these to identify areas that are likely to offer the finest spatial resolution for this application. We further demonstrate how isoscapes can be applied to back-trace animal migrations using real-world migration case studies of sea turtles and whales. We demonstrate that coastal areas and mid-latitude oceanic regions are likely to offer the best spatial resolution, and that migration pathways are able to be identified from successive barnacle shell samples. We expect that this work will allow for more efficient and precise future applications of barnacle shell isotope analyses to trace the movement and origin of barnacle hosts through marine waters.
了解动物和物体的运动有助于为物种保护和更广泛的环境管理提供信息（例如，通过确定海洋碎片的来源）。标记技术仅限于对未来运动的调查（例如，在应用标记之后），而无法了解动物或物体在遇到之前来自何处。然而，应用化学技术的研究能够解决遇到之前关于历史运动的问题，特别是通过分析来自迁徙动物组织或附着在迁徙宿主上的藤壶壳中的稳定同位素。藤壶壳同位素分析是一种很有前途的技术，可以为了解迁徙海洋动物的生态学提供新的认识，或者还可以了解海洋碎片的来源。在这里，我们使用全球数据集来评估藤壶壳同位素技术用于识别携带藤壶的动物和物体的起源和旅行路径的适用性。我们展示了藤壶壳方解石的第一个全球同位素景观图，利用这些图来确定最适合这种应用的区域。我们进一步展示了如何使用海龟和鲸鱼的实际迁徙案例研究，将同位素景观图应用于回溯动物迁徙。我们证明了沿海地区和中纬度海洋地区可能提供最佳的空间分辨率，并且可以从连续的藤壶壳样本中识别出迁徙路径。我们预计，这项工作将使未来更有效地利用藤壶壳同位素分析来追踪藤壶宿主在海洋中的运动和起源。
