abstract: The change in the intensity of bioluminescence fields in the coastal area of the western shelf of the Crimea in the dark time of day was discussed. It is noted, that the biomass of luminous organisms closely correlate with the biomass of plankton and other pelagic creatures, including commercial pelagic fish. The parameters of the basic biological rhythms of plankton communities are found using method of Fourier series. These rhythms leads to change of intensity of the bioluminescence field. It 
journal: Turkish Journal of Fisheries and Aquatic Sciences