Blooms of Pseudo-nitzschia species are frequent, but presently unpredictable, in the Juan de Fuca Eddy region off the coasts of Washington (US) and British Columbia (Canada). This upwelling eddy region is proposed to be the bloom commencement site, before cells are entrained into the coastal surface currents. During a shipboard study, we characterized the different stages of the Pseudo-nitzschia bloom development from its initiation and intensification, to its eventual sinking and dissipation. Specifically, we followed a water mass using lagrangian ARGOS-tracked drifters released at the eddy water mass and quantified production of dissolved and particulate domoic acid, and the physiological status of the Pseudo-nitzschia cells with regards to photosynthesis, nutrient needs and sinking rates, along with its relationship with competing species – in this case, the marine euglenoid, Eutreptiella spp. The drifter study allows for an interpretation of the presence or absence of Pseudo-nitzschia and domoic acid against active environmental factors – particularly copper and iron.

在华盛顿（美国）和不列颠哥伦比亚省（加拿大）沿岸的胡安·德·富卡·埃迪地区，伪造菌的繁殖频繁但目前无法预测。在将细胞夹带到沿海地表水流之前，该上升流涡流区域被认为是水华开始的地点。在船上研究中，我们表征了拟南芥开花的不同阶段，从其萌芽和增强到最终的下沉和消散。具体而言，我们使用在涡流水团处释放的拉格朗日ARGOS跟踪的浮标跟踪水团，并量化溶解的和颗粒状的二氢酸的产量，以及假性尼兹菌的生理状态有关光合作用，养分需求和下沉率的细胞，以及与竞争物种的关系–在这种情况下，是海洋类鳗鱼Eutreptiella spp。漂泊者研究可以解释是否存在伪性尼兹菌和多摩酸对活跃的环境因素（尤其是铜和铁）的影响。