Collaborative Research: Temporal and spatial scales of variability in bivalve connectivity.

幼虫连接，即亚种群交换幼虫的程度，已成为种群生态学、生物资源管理、生物多样性保护、入侵物种控制和栖息地恢复等领域的一个基本概念。然而，确定幼虫的扩散轨迹及其变异性的规模仍然是一项重大挑战。在这里，Levin博士、Muccino博士和Razmussen博士将使用前瞻性建模和追溯(元素指纹)方法相结合的方法来评估幼虫连接性的变异性及其对南加州贻贝种群的人口统计学影响。这个项目建立在对Mytild连通性的初步研究的基础上，以更深入、更紧密地结合物理/生物方法来解决变异性问题及其原因。这些合作的科学家将提出关于贻贝、加州贻贝和高氏贻贝连通性的空间和时间尺度的假设，检查它们在地点和物种之间的一致性。为实现这一目标，将通过以下途径：(A)每年在圣地亚哥县18个地点数次放养幼虫，以生成痕量元素指纹的参考信号；(B)收集新兵和对其幼虫贝壳进行元素分析以确定起源地点和区域；(C)在2个海湾地点和2个沿海地点收集高频数据，以分析招募活动的变异性、其与化学信号和招募来源的联系以及收集人口数据(不同大小的存活、生长和繁殖力)。通过沿海海洋和海湾的数值扩散模拟，以及随后与基于指纹的招募来源评估的比较，他们将研究环流、本地与远程强迫、海湾-海洋相互作用、事件和幼虫属性(垂直行为、释放时间、浮游持续时间)在确定连通性可变性方面的作用。人口学数据将与连接性数据相结合，以模拟观察到的Myild连接性模式的人口和元种群水平的健康结果。该项目的关键教育元素包括培训本科生和研究生进行综合沿海海洋物理学、幼虫生态学和人口学的跨学科研究。连通性研究的结果直接适用于商业和自然双壳类种群的养护和管理，并考虑到贻贝在保护岩石海岸生境方面的关键结构作用。

Larval connectivity, the extent to which sub-populations exchange larvae, has emerged as a fundamental concept within the diverse arenas of population ecology, biotic resource management, biodiversity conservation, invasive species control, and habitat restoration. However, determining dispersal trajectories of larvae and their scales of variability remain a major challenge. Here Drs. Levin, Muccino and Razmussen will use an integration of prospective modeling and retrospective (elemental fingerprinting) approaches to assess variability in larval connectivity and its demographic consequences for mytilid mussel populations in southern California. This project builds on initial studies of mytilid connectivity to address in greater depth and with a more strongly coupled physical/biological approach, questions of variability and its causes. These collaborating scientists will address hypotheses concerning the spatial and temporal scales of connectivity for mussels, Mytilus californianus and Mytilus galloprovincialis, examining their consistency among sites and species. This will be accomplished through (a) larval out-planting at 18 locations in San Diego County several times a year to generate reference signatures for trace elemental fingerprinting, (b) collection of recruits and elemental analyses of their larval shells to determine sites and regions of origins, and (c) high frequency data collection at 2 bay locations for M. galloprovincialis and 2 open coast locations for M. californianus to carry out weekly analysis of recruitment variability, its link to chemical signals and recruit origins, and for collection of demographic data (size-specific survivorship, growth and fecundity). Through numerical dispersal simulations of the coastal ocean and bays, and subsequent comparisons to fingerprinting based assessment of recruit origins, they will examine the roles of circulation, local vs. remote forcing, bay-ocean interaction, episodic events, and larval attributes (vertical behavior, release times, planktonic duration) in defining the variability of connectivity. Demographic data will be combined with connectivity data to model the population and meta-population level fitness consequences of observed mytilid connectivity patterns.Key educational elements of this project include the training of undergraduate and graduate students to conduct inter-disciplinary research that integrates coastal ocean physics, larval ecology and demography. The results of connectivity studies have direct applicability to conservation and management of commercial and natural bivalve populations, and given the key structural role of mussels, to the conservation of rocky shore habitats.