Feeding Ecology of Sea Otters in Soft-Bottom Habitats

海獭在所有海洋哺乳动物中是独一无二的， 觅食的前沿正在入侵历史上的觅食地， 水獭种群恢复并扩大了它们的活动范围。 该人群 扩张提供了重要的自然实验，有助于评估 水獭如何影响猎物种群、非猎物群落和底栖生物 栖息地 虽然大多数以前的研究社区的作用， 水獭来自多岩石的海岸，没有人记录这些 令人兴奋的自然实验，几乎没有什么是已知的 水獭在软沉积物环境中觅食的栖息地。 奥利弗 建议建立长期研究海獭如何利用 软沉积物猎物群落，主要由 蛤 一般的方法是找到活跃的觅食前线， 建立永久性的水下断面。 这些样带将 位于被严重开发的旧觅食地，最近， 在相对未开发的地区， 觅食地将被水獭入侵，在未开发的 水獭不太可能使用的区域。 一个这样的梯度 在科迪亚克岛附近的Afognak海峡附近有觅食活动。 尽管将沿着现有的 觅食梯度（觅食前沿）将提供相当多的见解 海獭数量的变化与猎物数量的变化之间的关系 社区，对永久样带的长期监测甚至 更重要的是，它将为海洋提供最直接的证据， 水獭在构建软沉积物群落中的作用。 这项工作是 与海獭的种群和行为研究密切配合 这将由阿拉斯加的美国鱼类和野生动物管理局完成。 这是一个本科院校研究奖。

Sea otters are unique among all the marine mammals because large foraging fronts are invading historical feeding grounds as the sea otter populations recover and expand their range. This population expansion provides important natural experiments that help to evaluate how otters affect prey populations, non-prey communities and benthic habitats. Although most previous studies of the community role of otters derive from the rocky shore, none have documented these exciting natural experiments and almost nothing is known about the foraging habitats of otters in soft-sediment environments. Oliver proposes to establish long-term studies of how sea otters utilize soft-sediment prey communities, which are primarily dominated by clams. The general approach is to locate active foraging fronts and to establish permanent underwater transects. These transects will be located in old feeding grounds that are heavily exploited, in recently invaded sites that are heavily exploited, in relatively unexploited feeding grounds that will be invaded by otters, and in unexploited areas that are not likely to be used by otters. One such gradient of feeding activity exists around Afognak Strait, by Kodiak Island. Although the quantitative sampling that will be done along existing feeding gradients (foraging fronts) will provide considerable insight into how changes in sea otter populations relate to changes in prey communities, the long-term monitoring of permanent transects is even more important and will provide the most direct evidence for the sea otter's role in structuring soft-sediment communities. This work is closely coordinated with population and behavior studies of sea otters that will be done by the U.S. Fish and Wildlife Service in Alaska. This is a Research in Undergraduate Institutions Award.