Global and local factors driving the phenology of Alexandrium minutum (Halim) blooms and its toxicity

The A. minutum bloom characteristics are defined. Only one bloom per year is measured and it may reach more than a million of cells L−1. Bloom period extends from April to October and the bloom length ranges from two weeks to six months. In the ecosystems studied, water temperature and river flow, as regional and local factors respectively, are the main environmental drivers influencing the magnitude, growth rate and length of the blooms. Bloom toxicity is linked to the bloom maximum abundance and river flow. This work provides new knowledge for further managing tools for A. minutum blooms in the ecosystems studied.