Elliott Smith Emma A, Moss Madonna L, Wellman Hannah P, Gill Verena A, Monson Daniel H, Newsome Seth D
Department of Biology and Center for Stable Isotopes, University of New Mexico, Albuquerque, NM, USA.
Department of Anthropology, Smithsonian National Museum of Natural History, Washington, DC, USA.
Proc Biol Sci. 2025 Jan;292(2039):20241682. doi: 10.1098/rspb.2024.1682. Epub 2025 Jan 29.
Retrospective datasets offer essential context for conservation by revealing species' ecological roles before industrial-era human impacts. We analysed isotopic compositions of pre-industrial and modern sea otters () to reconstruct pre-extirpation ecology and offer insights for management. Our study focuses on southeast Alaska (SEAK), where sea otters are recolonizing, and northern Oregon, where translocations are being considered. We measured bulk bone collagen C and N values and essential amino acid C values of extirpated sea otters from archaeological contexts, and bulk isotopic values from vibrissae of modern SEAK sea otters. We compare these results with published isotopic data of potential prey and additional archaeological datasets. In SEAK, our data show pre-industrial sea otter populations consumed infaunal bivalves and used soft-sediment (33%) and kelp forest habitats (67%), with sub-regional variation. We anticipate current populations will expand into this historical niche, and conflict with regional traditional/subsistence bivalve fisheries will persist. In northern Oregon, isotopic data from extirpated sea otters indicate past consumption of low trophic level invertebrates and a stronger reliance on kelp forests (88%) rather than soft-sediment habitats, highlighting the importance of kelp forests for future translocations. Our work exemplifies the value of historical ecology in informing conservation strategies for recovering species.
回顾性数据集通过揭示工业时代人类影响之前物种的生态作用，为保护提供了重要背景。我们分析了工业时代前和现代海獭的同位素组成，以重建海獭灭绝前的生态状况，并为管理提供见解。我们的研究重点是阿拉斯加东南部（SEAK），海獭正在那里重新定居，以及俄勒冈州北部，正在考虑在那里进行海獭迁移。我们测量了考古遗址中已灭绝海獭的骨骼胶原蛋白碳和氮值以及必需氨基酸碳值，以及现代SEAK海獭触须的整体同位素值。我们将这些结果与已发表的潜在猎物同位素数据和其他考古数据集进行比较。在SEAK，我们的数据表明，工业时代前的海獭种群以底栖双壳贝类为食，并利用软质沉积物栖息地（33%）和海带森林栖息地（67%），存在区域差异。我们预计当前的海獭种群将扩展到这个历史生态位，与区域传统/自给性双壳贝类渔业的冲突将持续存在。在俄勒冈州北部，已灭绝海獭的同位素数据表明，过去它们食用低营养级别的无脊椎动物，并且对海带森林（88%）的依赖程度高于软质沉积物栖息地，这突出了海带森林对未来海獭迁移的重要性。我们的工作例证了历史生态学在为恢复物种的保护策略提供信息方面的价值。
