Algal blooms in the Mediterranean Sea have been studied by means of SeaWiFS derived (1998-2003) data on chlorophyll-like pigment concentration. Statistics of blooming anomalies, as well as comparisons with analogous data collected in situ, were used to address the relationship between local and regional phytoplankton dynamics, in both the (mesotrophic, sometimes eutrophic) western basin and the (oligotrophic) eastern basin. Intense (coastal) blooming appeared to be linked to local factors, and only occasionally affected by mesoscale features such as eddies or meanders, suggesting that the forcing functions of local (harmful) algal blooms and regional blooms are different, or overlap only marginally.