Forays and Foraging by Marine Zooplankton

海洋浮游动物的袭击和觅食

• 批准号: 0525943
• 负责人: Bruce Frost
• 金额: --
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-10-01 至 2009-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0525943&HistoricalAwards=false
• 关键词: Forays; Foraging; Marine; Zooplankton; Forays; Foraging; Marine; Zooplankton

Intellectual Merit: A major challenge for biological oceanography is to understand and predict the vertical distribution and foraging behavior of planktonic animals. These organisms play central roles in pelagic ecosystems as consumers and producers of particles and as crucial links in pelagic food webs as prey for higher trophic types such as fish. A predictive understanding of the roles of zooplankton in these processes hinges on knowledge of their depth selection and foraging behavior. For example, where a planktonic animal forages in the water column can profoundly affect not only its feeding rate and growth rate, but also where it produces particles associated with its feeding. Moreover, in vertically structured advective fields, the dispersal of individuals depends on their position in the water column that may be dictated by other properties. Although diel vertical migration is the most conspicuous expression of depth selection and foraging behavior in zooplankton, there is much evidence indicating that zooplankton make excursions of substantial vertical extent on time scales shorter than the diel period. The biological significance of such behavior is currently unknown, but if frequent and widespread, its inclusion in models of zooplankton population dynamics and dispersal will be essential. The goal of this research is to test, in the ocean, the hypothesis that when occupying near surface waters planktonic copepods make repeated vertical excursions (forays) into and out of the food-rich layer. The Investigators will test the hypothesis by directly intercepting (trapping) vertically migrating individual adults and the last pre-adult stage (copepodid stage 5) of three species of planktonic copepods. Copepods will be sampled on sufficiently short time scales to detect repeated forays and to assess whether the forays are for the purpose of feeding. The research team will measure a small number of key indicators of physiological state and condition to assess the physiological consequences for individual copepods of such foraging behavior. The observations will be obtained in different seasons with different feeding conditions, water column physical structure (intensity of thermal stratification) and nocturnal period. Finally, they will integrate the observations in an individual-based model of copepod forays and foraging. The results of the research will be important for identifying and assessing processes and their potential significance in determining the vertical distribution and foraging behavior of zooplankton. These considerations are fundamental not only to understanding and modeling the population dynamics of marine zooplankton, but also to predicting the possible response of zooplankton to environmental changes, such as those associated with global climate change, and to understanding the vertical flux of materials, nutrients, and energy from surface waters to depth in the ocean.Broader impacts: The project will involve direct participation of two graduate student research assistants, who will pursue related research projects. The research will also develop a partnership with NOAA's Pacific Fisheries Environmental Laboratory in Pacific Grove, CA. Relevant to that partnership, the insights gained in the proposed research should also be valuable to fisheries management in terms of advancing understanding of how environmental change may affect the distribution and availability of a major class of prey items for many managed living marine resources, such as juvenile salmon and other small pelagic fish.

智力优点：生物海洋学的主要挑战是了解和预测浮游动物的垂直分布和觅食行为。这些生物作为颗粒的消费者和生产国，在质食物网的关键环境中起着核心作用，作为较高营养类型（例如鱼）的猎物的关键联系。对浮游动物在这些过程中的作用的预测理解取决于其深度选择和觅食行为的知识。例如，在水柱中的浮游动物饲料中，不仅会影响其进食率和生长速率，而且还会影响与其饲料相关的颗粒。此外，在垂直结构化的对流场中，个体的分散取决于其在水柱中可能由其他特性决定的位置。尽管DIEL垂直迁移是浮游动物中深度选择和觅食行为最明显的表达，但有很多证据表明，浮游动物的时间尺度比DIEL时期短。这种行为的生物学意义目前尚不清楚，但是如果频繁且广泛地扩展其包含在浮游动力学模型和分散的模型中。这项研究的目的是在海洋中检验一个假设，即在地表水附近占据时，浮游生物copepods将重复的垂直偏移（弹出）重复进入和偏出富含食物的层。研究人员将通过直接拦截（捕获）垂直迁移的个体成年人和三种浮游生物copepods的三种种类的成年阶段（共卵形5期）来检验该假设。 Copepods将在足够短的时间尺度上进行采样，以检测重复的尝试，并评估出发是否是为了进食的目的。研究团队将测量少数的生理状态和状况的关键指标，以评估这种觅食行为的单个copepods的生理后果。观察结果将在不同季节以不同的饲养条件，水柱物理结构（热分层的强度）和夜间周期获得。最后，他们将将观测值集成到基于个体的copepod尝试和觅食模型中。研究结果对于确定和评估过程及其在确定浮游动物的垂直分布和觅食行为方面的潜在意义将很重要。这些考虑不仅是理解和建模海洋浮游生物的种群动态，而且还预测了浮游动物对环境变化的可能反应，例如与全球气候变化相关的变化，以及了解材料，营养和能量的垂直范围的垂直范围，从地表水中逐渐参与研究人员参与了两次学生的参与。这项研究还将与位于加利福尼亚太平洋格罗夫的NOAA太平洋渔业环境实验室建立合作伙伴关系。与该合作伙伴关系相关的是，在拟议的研究中获得的见解也应该对渔业管理有价值，这是在了解环境变化如何影响许多托管生存海洋资源（例如少年鲑鱼和其他小型Pelagic Fish）的主要猎物分布和可用性方面的理解。