WALRUS - Walrus Adaptability and Long-term Responses; Using multi-proxy data to project Sustainability

海象 - 海象的适应性和长期反应；

• 批准号: 1263848
• 负责人: Nicole Misarti
• 金额: $ 170.73万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-15 至 2022-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1263848&HistoricalAwards=false
• 关键词: WALRUS; Walrus; Adaptability; Long; term

The Pacific walrus (Odobenus rosmarus divergens) is one of many species affected by recent environmental change in the Arctic. Much attention has focused on the loss of sea ice recorded from 2007-2012, the concomitant appearance of thousands of walruses on Alaska's and Russia's beaches, and the unfortunate consequence of large numbers of trampling mortalities. In addition, an unusual number of walruses in poor body condition were reported on Wrangel Island in 2007, many of which subsequently died. While walrus haul-out and mortality events are not historically isolated occurrences, these past haul-outs on Alaska's coasts, associated with reduced sea ice abundance, signify a change to this population. These occurrences are disquieting taken together with a decrease in estimated walrus based on surveys from 2006 versus 1990, (129,000 in 2006 compared to 200,000 in 1990), and current data on reduced fertility. The Pacific walrus is of critical importance to subsistence consumers in Alaska (and other areas of the Arctic). Despite impressive data from in-depth studies of Pacific walruses over the last 40-50 years, it is difficult to implement proposed co-management and conservation plans based on data from such a relatively short time span, much less project the impact of additional changes to the Arctic ecosystem on both walruses and humans subsisting on them.This project aims to integrate several disciplines including archaeology, ethnology, biology, and ecology using diverse sources of data including DNA, stable isotope, steroid, and trace element analysis as well as to ascertain long-term trends of walrus feeding ecology, foraging location, and stock genetics over the last two millenia. This time frame includes large climatic anomalies such as the Medieval Warm and the Little Ice Age, thereby presenting scientists with the possibility of understanding how walruses adapt during times of stress and change. Present-day samples will be obtained from Alaskan subsistence hunters, historic samples will be acquired from museums, and prehistoric samples from archaeological collections. Each type of data will act as a building block to better understand walruses and how they adapt to change in Arctic ecosystems. DNA analysis will provide insights into population bottlenecks and potentially adaptive differentiation between stocks. Stable isotope analysis of bone collagen and growth ring layers of teeth will define overall feeding ecologies of individuals through time. Trace element analysis will reveal foraging locations, potential population structure, and changes of essential and non-essential elements over time. Bone steroid hormones (i.e., stress hormones) can delineate population structure and health over time, and translation of historic taped interviews and use of previously archived studies will reveal traditional knowledge of walrus habitats and feeding habits over the last 100 years.

太平洋海象是受北极近期环境变化影响的众多物种之一。人们的注意力集中在2007-2012年记录的海冰消失、阿拉斯加和俄罗斯海滩上相伴出现的数千只海象，以及大量踩踏死亡造成的不幸后果上。此外，据报告，2007年兰格尔岛上出现了数量不同寻常的身体状况不佳的海象，其中许多后来死亡。虽然海象的迁出和死亡事件在历史上并不是孤立的事件，但阿拉斯加海岸过去的这些迁出与海冰丰度减少有关，标志着这一种群的变化。这些情况令人不安，加上根据2006年与1990年的调查(2006年为129,000只，1990年为200,000只)估计海象数量的减少，以及目前关于生育率下降的数据。太平洋海象对阿拉斯加(和北极其他地区)的自给自足消费者至关重要。尽管过去40-50年来对太平洋海象的深入研究提供了令人印象深刻的数据，但基于相对较短的时间跨度的数据很难实施拟议的共同管理和保护计划，更不用说预测北极生态系统的额外变化对海象及其生存的人类的影响。该项目旨在利用包括DNA、稳定同位素、类固醇和微量元素分析在内的多种数据来源整合考古学、民族学、生物学和生态学等多个学科，并确定过去两千年来海象摄食生态、觅食地点和种群遗传学的长期趋势。这一时间框架包括大型气候异常，如中世纪暖期和小冰期，从而为科学家提供了了解海象在压力和变化时期如何适应的可能性。目前的样本将从阿拉斯加自给自足的猎人那里获得，历史样本将从博物馆获得，史前样本将从考古收藏品中获得。每种类型的数据都将作为构建块，更好地了解海象以及它们如何适应北极生态系统的变化。DNA分析将提供对种群瓶颈和潜在的种群之间适应性差异的洞察。牙齿的骨胶原和生长环层的稳定同位素分析将随着时间的推移定义个体的整体摄食生态。微量元素分析将揭示觅食地点、潜在种群结构以及必需和非必需元素随时间的变化。骨类固醇激素(即应激激素)可以描述随着时间的推移海象种群结构和健康状况，翻译历史录音采访和使用以前存档的研究将揭示过去100年来关于海象栖息地和食性的传统知识。