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

白令海东南部内前沿花后生产动态和生态系统影响的合作研究

• 批准号: 9819251
• 负责人: George Hunt
• 金额: $ 34.28万
• 依托单位: University of California-Irvine
• 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 2002-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9819251&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]每年有数百万只短尾鹱（Puffinus tenuirostris）从澳大利亚迁徙到白令海，在白令海的内大陆架上觅食。这种每年跨赤道迁徙的进化意味着白令海上的这些鸟一定有大量的猎物。1997年和1998年，白令海东部的异常天气模式导致了水文和水循环的显著变化。由此导致的生态系统异常包括白令海第一次有记录的球石藻爆发，大约10%的迁徙海鸥饿死，以及1997年和1998年布里斯托尔湾红鲑鱼渔业的崩溃。这个研究项目将继续测试这样一个假设，即白令海东南部内前缘的初级产量比非前缘的持续时间更长，并且这种产量在整个夏天为支持海鸥、鲑鱼和它们的浮游动物猎物的食物网提供能量。根据1997年和1998年的调查结果，将使用季节和年度比较来检验关于风暴和营养物平流作用的其他假设。这项合作研究将收集和解释对内前部附近的物理和生物特征的观察结果，以确定：1)浮游带营养物的可利用性，2)营养物垂直通量增强的物理过程，3)初级生产，4)近地表浮游生物群和其他大、微型浮游动物群的分布、丰度和营养生态，5)剪切水的分布、丰度和觅食生态，6)通过稳定同位素富集，浮游植物到剪切水的营养途径。白令海东南部拥有世界上最丰富的渔业资源之一；狭鳕、鲑鱼、大比目鱼和螃蟹每年的收入超过20亿美元。尽管如此，沿海地区和内陆地区，也就是海鸥、小鲑鱼和一些螃蟹幼虫聚集觅食的地方，还没有得到很好的研究。这项研究很重要，因为它将：1)与天气模式的变化如何影响影响生态系统功能的物理过程有关；2)首次考察夏季内锋的物理过程，以及花期后初级生产中锋的作用；3)关注扩展生产的生态作用；4)将海鸟跨赤道迁徙模式的进化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锋和物种。因此，研究结果应普遍适用于了解和管理世界上一些生产力最高的海洋。