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

美国GLOBEC：乔治河岸上pseudoalanus种群的维持ann Bucklin和Dennis J. McGillicuddy浮游桡足类兄弟物种，moultonpseudoalanus和P. newmani，在春季和夏季在乔治河岸对称地出现。尽管它们在形态上有明显的相似性，但它们在生态的许多方面都不同，包括：分布模式和丰度；首选栖息地;以及繁殖的季节性时间。与P. newmani相比，P. moultoni在60 m等深线内的Georges Bank混合良好的顶部更为丰富（Bucklin et al., 1998, march . Biol）。（待印）。我们假设，P. moultoni种群是通过本地繁殖和补充在乔治河岸维持的，并且该物种在60 m等深的潮汐混合锋内的保留是通过与物理过程（潮汐混合锋动力学）相关的行为（垂直分布）进行的。这一假设将通过与环流模式（基于1999年1月至6月收集的大尺度调查样本）和与潮汐混合锋的平流和混合有关的三维小尺度分布（在1999年5月和6月提出的实地实验期间）的特征、特定阶段的莫尔托尼和纽马尼p.m oultoni和纽马尼p.m oultoni的分布和丰度进行检验。这项工作的目的是了解P. moultoni如何在乔治海岸复杂多变的流场中持续存在和增殖。技术方法将是利用物种特异性竞争性PCR识别莫尔托尼假单孢菌的所有生命阶段，并利用在已知物理场中观察到的分布进行数值模拟实验。该项目的意义在于了解种群动态与海洋过程之间的相互作用，以确定乔治滩浮游动物群落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.