PRF: Energetics and Hydrodynamics of Suspension Feeding in Blackfish: Ontogenetic Shift in Feeding Mode

成年悬食鱼（如凤尾鱼和鲭鱼）通过张开嘴游动来捕获多个猎物。尽管这些鱼类在经济和生态方面具有重要意义，但很少有研究对悬浮摄食的功能形态学、能量学和流体动力学的假设进行检验。在幼年时期，这些物种是颗粒捕食者，它们用吸力捕捉单个猎物。从颗粒进料到悬浮进料的深刻转变为从机械角度研究悬浮进料提供了一个理想的机会。呼吸生理学和生物力学技术将被应用于测试两个主要假设：第一，水通过口腔和眼腔的水力阻力，以及整个身体在张开嘴巴游泳时的水动力阻力，在幼年黑鱼中明显高于成年黑鱼；其次，摄食的能量消耗在不同摄食方式之间的转换过程中急剧下降。虽然过渡后悬浮摄食的能量消耗可能较低，但身体上的限制可能会阻止幼鱼进行悬浮摄食。对浮游生物种群动态、幼鱼和成鱼之间的资源分配以及鱼类悬浮摄食的进化具有重要意义。加州大学戴维斯分校将作为该博士后研究奖学金项目的主办机构。该奖项的期限为两年。

Adult suspension feeding fishes (e.g., anchovies and mackerels) capture multiple prey by swimming with mouths held open. Despite the economic and ecological importance of these fishes, few studies have tested hypotheses concerning the functional morphology, energetics, and hydrodynamics of suspension feeding. As juveniles, these species are particulate feeders that capture individual prey using suction. The profound shift from particulate feeding to suspension feeding offers an ideal opportunity to investigate suspension feeding from a mechanistic perspective. The techniques of respiratory physiology and biomechanics will be applied to test two main hypotheses: first,that the hydraulic resistance of the water path through the oral and opercular cavities, as well as the hydrodynamic drag of the entire body during swimming with the mouth held open, is significantly higher in juvenile blackfish than in adults; and secondly, that the energetic cost of feeding decreases abruptly over the transition between feeding modes. Although the energetic cost of suspension feeding may be low after the transition, physical constraints may prevent juveniles from suspension feeding. Information on the factors involved in the switch between feeding modes will have implications for plankton population dynamics, resource partitioning between juvenile and adult fishes, and the evolution of suspension feeding in fishes. The University of California at Davis will serve as the host institution for this postdoctoral research fellowship project. The duration of this award is two years.