A Bloom of the Planktonic Diatom, Cerataulina pelagica, off the Coast of Northeastern New Zealand in 1983, and its Contribution to an Associated Mortality of Fish and Benthic Fauna

A bloom of Cerataulina pelagica dominated the sea area off the north‐east coast of New Zealand for three months in the summer of 1982–83, and has been related to unusually calm conditions associated with an unusually low Southern Oscillation Index. Deaths of benthic shellfish during the bloom were attributed to anoxia induced by the bacterial decay of the diatom cells. Death of bony fish caught on long‐lines was attributed to anoxia and the clogging of the gills with mucilage produced by the diatoms.