Enhanced echograms of high-frequency sound (120 and 200 kHz) from entire tracklines surveyed during summer and winter of 1991–1994 were evaluated to observe volume backscattering in the Black Sea. Echo intensities were filtered through two thresholds for distinguishing suspended scatterers from active swimmers (fish). It was postulated that the backscattering by the suspended matters was associated with bathymetry, seasonal stratification and different levels of mixing of water, and daily migration of zooplankton. The scattering was layered in association with the physical structure in the open water. As bottom depth was shoaled, the vertical structure became more homogenous. Biological scatterers were diversified with zooplanktoners and pelagic fish (anchovy and sprat). Copepod and gelatinous organisms (comb-jelly and moon jellyfish) appeared to be responsible for the zooplanktonic scatterers. Changes in seasonal and diurnal migrational patterns of fish were investigated. During the summer, pelagic fish schools were observed in an offshore area, whereas in winter the schools were confined to the coastal area. In regard to the schooling density, higher concentrations were found in winter.