The Paleoecology of Pinnipeds on the Pacific Rim

太平洋沿岸鳍足类动物的古生态学知识价值——最近的研究表明，人类，包括史前人类，在塑造他们所居住的生态系统方面发挥了重要作用，而且我们今天熟悉的一些生态系统在最近的过去的运作方式不同。历史和古生态数据为保护区考虑未来的管理决策提供了重要的背景信息，特别是对于那些最近经历了种群数量下降的物种。我们的总体目标是探索过去5000年来环境和人为因素如何相互作用，从而产生东北太平洋沿岸的生态变化。这些变化的最完整记录是在沿海考古遗址中发现的，在那里可以研究过去陆地和海洋生态系统的动物，以调查古生态变化。此外，对主要生态变化的认识对于考古学家试图破译人类人口和资源利用的变化将是重要的。在过去的研究中，利用同位素和考古数据研究了北方毛皮海豹，表明该物种在过去的1000年里改变了其繁殖和迁徙行为。海狗骨头的年代也表明，当地繁殖群的崩溃并不是在太平洋边缘同步发生的。本研究将通过构建同位素组成、存在/不存在、相对丰度和年龄/性别分布的时间序列，研究中全新世以来四种不同鳍足类动物觅食、迁徙、断奶和拖出行为的变化。此外，我们将开发两种新的方法来评估鳍足动物的断奶年龄。第一项研究将使用尖牙的生长结构作为断奶年龄和母体投资的替代指标。另一种是生物地球化学方法，利用骨生长系列和牙本质中N同位素比率的变化。我们将重点关注四个鳍状多样性中心——东部阿留申群岛、美加边境、俄勒冈海岸和海峡群岛。该项目将包括广泛的文献检索和将现有的动物信息汇编成一个关于东北太平洋边缘全新世鳍状动态的数据库。更广泛的影响-这项研究将展示如何从考古数据中了解受威胁物种的生态。这对孑遗种群中的物种很重要，它们目前的生态可能受到最近的开发或环境变化的影响。我们将研究的四种物种中有三种目前正经历着数量的快速下降，但导致这些下降的原因还远不清楚。这项研究将提供这些物种长期生态的基线数据，并表明它们在过去是否因人为或环境扰动而经历过类似的衰退。我们将与自然保护生物学家合作，将我们的数据提供给那些做出管理决策的人。为此目的，我们将在2004年冬季共同主办一次会议，由加州大学太平洋太平洋研究中心资助，届时考古学家、历史学家、海洋哺乳动物生态学家、保护生物学家和社会科学家将齐聚一堂。我们的目标是在当今这些物种的生态背景下评估东北太平洋鳍足类的考古和历史记录，然后制定策略，将这些信息整合到保护政策制定者的决策过程中。这个项目更直接的影响将是UCSC的研究生和本科生的教育。此外，我们对海洋哺乳动物生态学的史前方法在2002年和2003年被开发成COSMOS（加利福尼亚州数学和科学暑期学校）的一个模块。一组不同的学生（8-12年级）参加了为期四周的课程，该课程整合了实地，实验室和课堂练习，旨在向学术和积极的年轻人介绍科学。

The Paleoecology of Pinnipeds on the Pacific RimIntellectual Merits - Recent studies have shown that humans, including prehistoric people, play a major role in shaping the ecosystems they inhabit, and that some of the ecosystems we are familiar with today operated differently in the recent past. Historical and paleoecological data provide crucial contextual information for the conservation communities considering future management decisions, especially for species that have witnessed relatively recent population declines. Our overarching goal is to explore how environmental and anthropogenic factors interacted to generate ecological shifts on the northeastern Pacific coast over the past 5000 years. The most complete record of these changes is found in coastal archaeological sites, where the faunas of past terrestrial and marine ecosystems can be studied to investigate paleoecologic shifts. Furthermore, the recognition of major ecological shifts will be important for archaeologists attempting to decipher changes in human demography and resource utilization. In past studies, northern fur seals were studied using isotopic and archaeological data to show that the species has changed its breeding and migratory behavior over the past 1000 years. Fur seal bones were also dated to show that the collapse of local breeding colonies was not synchronous across the Pacific margin. For this study, we will investigate changes in foraging, migratory, weaning, and haul-out behavior in four different pinniped species since the mid-Holocene through construction of time series on isotopic composition, presence/absence, relative abundance, and age/sex distribution. In addition, we will develop two new methods to assess weaning age in pinnipeds. The first will use growth structures in pinniped teeth as proxies for weaning age and maternal investment. The other is a biogeochemical approach that uses changes in the N isotope ratios in bone growth series and tooth dentin. We will focus on four centers of pinniped diversity - the eastern Aleutian Islands, the US-Canadian border, the Oregon coast, and the Channel Islands. This project will include an extensive literature search and compilation of existing faunal information into a database on Holocene pinniped dynamics along the NE Pacific margin.Broader Impacts - This study will show how insights into the ecology of threatened species may be gleaned from archaeological data. This is important for species in relict populations, whose current ecology may be shaped by recent exploitation or environmental change. Three of the four species we will study are presently undergoing rapid population declines, but the causes for these declines are far from clear. This study will provide baseline data on the ecology of these species over deep time, and indicate whether or not they experienced similar declines in the past in relation to anthropogenic or environmental perturbations. We will work with conservation biologists to make our data available to those making management decisions. To this end, in winter 2004 we will co-host a conference, funded by the UC-PACRIM, which will bring together archaeologists, historians, marine mammal ecologists, conservation biologists, and social scientists. Our goal is to evaluate the archaeological and historical record of NE Pacific pinnipeds in the context of the ecology of these species today, and then to develop strategies for integrating this information into decision-making processes of conservation policy makers. A more immediate impact of this project will be the education of graduate and undergraduate students at UCSC. In addition, our prehistoric approach to marine mammal ecology was developed into a module for COSMOS (California State Summer School for Mathematics and Science) in 2002 and 2003. A diverse group of students (grades 8-12) took part in a 4-week course that integrated field, laboratory, and classroom exercises designed to introduce scholarly and motivated young people to science.