US GLOBEC: Maintenance of Pseudocalanus spp. Populations in Georges Bank

美国GLOBEC：伪哲水蚤属的维护。乔治河岸的种群Ann Bucklin和Dennis J. McGillicuddy在春季和夏季，在乔治河岸共域地出现了浮游桡足类的兄弟物种，Pseudocalanus moultoni和P. newmani。 尽管它们在形态上有着显著的相似性，但这些物种在生态学的许多方面都存在差异，包括：分布和丰度模式;首选栖息地;以及繁殖的季节性时间。 与P. newmani相比，P. moultoni在60米等深线内的乔治浅滩混合良好的波峰上更丰富（Bucklin等人，1998年3月，生物学，出版中）。 我们假设，种群的P. moultoni保持在乔治银行的本地繁殖和招聘，该物种是差异保留在潮汐混合前位于沿着60米等深线的行为（垂直分布）的物理过程（潮汐混合前的动态）。 将通过表征与环流模式相关的全岸、特定阶段的毛氏原甲藻和纽氏原甲藻的分布和丰度（基于1999年1月至6月收集的大尺度调查样本）以及与潮汐混合锋中的平流和混合相关的三维小尺度分布（在1999年5月和6月的现场实验期间）来检验这一假设。 本研究的目的是了解毛氏肺吸虫如何在复杂多变的乔治滩流场中持续生存和增殖。 技术方法将是使用物种特异性竞争PCR来识别所有生命阶段的P. moultoni，并使用在已知物理场中观察到的分布进行数值模拟实验。 该项目的意义是了解种群动态和海洋过程之间的相互作用，以确定乔治海岸浮游动物组合的重要成员的分布和丰度。

U.S. GLOBEC: Maintenance of Pseudocalanus spp. populations on Georges BankAnn Bucklin and Dennis J. McGillicuddy The planktonic copepod sibling species, Pseudocalanus moultoni and P. newmani, occur sympatrically during the spring and summer on Georges Bank. Despite their marked morphological similarity, the species differ in many aspects of their ecology, including: patterns of distribution and abundance; preferred habitat; and seasonal timing of reproduction. In comparison to P. newmani, P. moultoni is more abundant on the well-mixed crest of Georges Bank within the 60 m isobath (Bucklin et al., 1998, Mar. Biol., in press). We hypothesize that populations of P. moultoni are maintained on Georges Bank by local reproduction and recruitment, and that the species is differentially retained within the tidal-mixing front located along the 60 m isobath by behavior (vertical distribution) in relation to physical processes (dynamics of the tidal-mixing front). This hypothesis will be tested by characterization of Bank-wide, stage-specific distribution and abundance of P. moultoni and P. newmani in relation to circulation patterns (based on Broadscale Survey samples collected from January to June, 1999) and three-dimensional small-scale distributions in relation to advection and mixing in the tidal-mixing front (during field experiments proposed for May and June, 1999). The goal of this work is to understand how P. moultoni may persist and proliferate in the complex and variable flow field over Georges Bank. The technical approach will be to identify all life stages of P. moultoni using species-specific competitive PCR, and to perform numerical modeling experiments using observed distributions in a known physical field. The significance of this project is to understand the interplay between population dynamics and ocean processes in determining the distribution and abundance of important members of the Georges Bank zooplankton assemblage.