A Collaborative Study of the Dynamics and Ecosystem Implications of Post-Bloom Production at the Inner Front of the Southeast Bering Sea

东南白令海内前沿花后生产动态和生态系统影响的合作研究

• 批准号: 9819273
• 负责人: Terry Whitledge
• 金额: $ 37.72万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9819273&HistoricalAwards=false
• 关键词: Collaborative; Study; Dynamics; Ecosystem; Implications

AbstractHunt U of CA, Irvine 9819251Zeeman U of New England 9907097Whitledge U of AK, Fairbanks 9819273Each year millions of short-tailed shearwaters (Puffinus tenuirostris) migrate from Australia to the Bering Sea to forage over the inner shelf. The evolution of this annual trans-equatorial migration implies that extraordinary amounts of prey must be readily available to these birds in the Bering Sea. In 1997 and 1998, unusual weather patterns in the eastern Bering Sea resulted in significant changes in hydrography and water circulation. The resultant ecosystem anomalies included the first recorded coccolithophore bloom in the Bering Sea, the starvation of about 10% of the migrant shearwaters present, and the collapse in both 1997 and 1998 of the Bristol Bay sockeye salmon fishery. This research project will continue testing the hypothesis that elevated primary production at the inner front of the southeastern Bering Sea continues longer than in non-frontal waters, and that this production provides an energy source throughout the summer for a food web that supports shearwaters, salmon, and their zooplankton prey. Based on findings in 1997 and 1998, additional hypotheses concerning the roles of storms and advection of nutrients will be tested using seasonal and inerannual comparisons. This collaborative study will collect and interpret observations on physical and biological features in the vicinity of the inner front to determine: 1) the availability of nutrients in the euphotic zone, 2) the physical processes responsible for enhanced vertical flux of nutrients, 3) primary production, 4) the distribution, abundance and trophic ecology of near-surface swarms of euphausiids and other macro- and micro-zooplankton, and 5) the distribution, abundance, and foraging ecology of shearwaters, and 6) by stable isotope enrichment, trophic pathways from phytoplankton to shearwaters at and away from the front.The southeastern Bering Sea supports one of the world's richest fisheries; walleye pollock, salmon, halibut and crab generate over 2 billion dollars in revenue each year. Despite this, the coastal domain and inner front, where shearwaters, young salmon and some crab larvae congregate to forage, has not been well studied. The study is important because it will: 1) relate how variation in weather patterns forces physical processes that affect ecosystem function; 2) be the first examination of the physical processes of the inner front during summer and of the role of the front in post-bloom primary production; 3) focus on the ecological role of the extended production, and 4) relate the evolution of trans-equatorial migration patterns of seabirds to biophysical processes that create predictable sources of prey. These questions are addressed by focusing on species and regions with which the investigators are familiar; however, the results can be applied to numerous continental shelf tidal fronts and species. Thus, the results should have a general applicability to understanding and managing some of the world's most productive seas.

摘要 Hunt 加州大学，欧文 9819251Zeeman 大学，新英格兰 9907097Whitledge 大学，AK 费尔班克斯 9819273 每年，数以百万计的短尾海鸥 (Puffinus tenuirostris) 从澳大利亚迁徙到白令海，在内陆架上觅食。 这种一年一度的跨赤道迁徙的演变意味着，白令海的这些鸟类必须随时可以获得大量的猎物。 1997年和1998年，白令海东部异常的天气模式导致水文和水循环发生重大变化。 由此产生的生态系统异常现象包括白令海首次出现有记录的颗石藻大量繁殖、约 10% 的迁徙海鸥遭受饥饿，以及 1997 年和 1998 年布里斯托尔湾红鲑鱼渔业的崩溃。 该研究项目将继续测试以下假设：白令海东南部内前沿初级生产力的提高持续时间比非前沿水域持续时间更长，并且这种生产在整个夏季为海鸥、鲑鱼及其浮游动物猎物的食物网提供能源。 根据 1997 年和 1998 年的研究结果，将使用季节和年际比较来测试有关风暴和平流营养物作用的其他假设。 这项合作研究将收集和解释对内锋附近物理和生物特征的观察结果，以确定：1）富光区营养物质的可用性，2）负责增强营养物质垂直通量的物理过程，3）初级生产，4）近地表磷虾和其他大型和微型浮游动物群的分布、丰度和营养生态学，以及 5) 海鸥的分布、数量和觅食生态，以及 6) 稳定同位素富集、从浮游植物到前沿和远离海鸥的营养途径。白令海东南部支持着世界上最丰富的渔业之一；狭鳕、鲑鱼、大比目鱼和螃蟹每年创造超过 20 亿美元的收入。 尽管如此，海鸥、幼鲑鱼和一些螃蟹幼虫聚集觅食的沿海地区和内锋尚未得到充分研究。 这项研究很重要，因为它将：1）关联天气模式的变化如何迫使影响生态系统功能的物理过程； 2）首次检查夏季内锋的物理过程以及锋在花后初级生产中的作用； 3）关注扩展生产的生态作用，4）将海鸟跨赤道迁徙模式的演变与创造可预测猎物来源的生物物理过程联系起来。 这些问题是通过关注研究人员熟悉的物种和地区来解决的；然而，这些结果可以应用于许多大陆架潮汐锋和物种。 因此，研究结果应该普遍适用于理解和管理世界上一些生产力最高的海洋。