Blooms of cyanobacteria are recurrent phenomena in coastal estuaries. Their maximum abundance coincides with the productive period zooplankton and pelagic fish. Experimental studies indicate that diazotrophic, i.e. dinitrogen (N2)-fixing cyanobacterial (taxonomic order Nostocales) blooms affect zooplankton, as well other phytoplankton. We used multidecadal monitoring data from one archipelago s...