Collaborative Research: Estuarine Crab Transport: Linking Post-Settlement Dispersal, Bio-Physical Mechanisms and Hydrodynamic Corridors

幼体最初定居后的二次远洋扩散可能会严重影响当地和区域的种群动态，但在招募研究中很少考虑二次扩散。虽然目前已认识到定居后蓝蟹扩散在确定北卡罗来纳州帕姆利科湾的补充模式方面的相对重要性，但尚未探讨引发早期幼蟹离开定居栖息地的因素、调节跨声运输的机制以及重新分配到替代栖息地的种群一级后果。这个项目将通过一项跨学科研究来解决这些问题，其内容包括：(1)在外滩声音一侧的海草床上进行小规模实地测量，以确定促使栖息地最初迁移的因素；(2)进行实验室实验，以测试推动中上层迁徙的行为机制；(3)进行全声水文学调查，以确定Pamlico声循环的特征，同时对仔蟹和幼蟹的时空分布进行天气学测量。该项目将在2002-2003年期间进行，以利用另一个国家科学基金会奖支持的同时进行的幼体和幼体采样。该项目将有助于理解在不是由潮汐运动主导，而是由不规则或持续的风致运动主导的河口，中上层扩散是如何发生的。过去对具有强烈潮汐信号的系统(例如切萨皮克和特拉华湾)的补充动力学的概括可能不能准确地描述主要由风驱动的大型系统(如Pamlico Sound)中的河口补充模式。

Secondary pelagic dispersal of juvenile benthic organisms following initial larval settlement may strongly influence local and regional population dynamics, yet secondary dispersal is rarely considered in recruitment studies. While the relative importance of post-settlement blue crab dispersal in determining recruitment patterns in Pamlico Sound, NC, is presently recognized, the factors initiating movement by early juvenile blue crabs away from settlement habitats, the mechanisms mediating across-sound transport, and the population-level consequences of redistribution to alternative habitats, have not yet been explored. This project will address these issues through an interdisciplinary study that incorporates: (1) small-scale field measurements in seagrass beds along the sound-side of the Outer Banks to identify the factors cueing initial movement from settlement habitats, (2) laboratory experiments to test the behavioral mechanisms that drive pelagic emigration, and (3) sound-wide hydrographic surveys to characterize Pamlico Sound circulation coupled with synoptic measurements of the spatiotemporal distribution of postlarval and juvenile blue crabs. The project will be conducted during 2002-2003 to take advantage of concurrent postlarval and juvenile sampling supported by another NSF award. This project will contribute to the understanding of how pelagic dispersal occurs in estuaries that are not dominated by tidal motions, but by irregular or persistent wind-induced motions. Generalizations of recruitment dynamics from past work on systems with strong tidal signals (e.g., Chesapeake and Delaware Bays) may not accurately characterize patterns of estuarine recruitment in predominantly large, wind-driven systems such as Pamlico Sound.