Effect of vertical mixing on the vertical distribution of copepods in coastal waters

The vertical distribution of copepod adult stages and nauplii had been studied in a coastal water before and during homogenization of the water column due to wind. When the water column was stratified, the vertical distribution of the zooplankton was also stratified, as is generally described in the literature. During homogenization of the water column different patterns of vertical distribution were observed. The less active nauplius stage was evenly distributed, even though adult stages always exhibited a stratified distribution. Oithona similis and Microsetella norvegica exhibited the same distribution in stratified and unstratified water columns. Temora longicornis and Pseudocalanus sp. were deeply distributed in a less turbulent area. The causes of these changes are discussed.