[The characteristics of the circadian motor activity of sturgeons and their hybrids studied by a motion picture-TV method].

Technique of slow-motion shot was used for simultaneous automatic recording of behaviour of sturgeon species Acipenser nudiventris and its hybrid with white sturgeon, Huso huso. The hybrids and the individuals of the paternal species were placed in two separate aquaria under the conditions of constant light. Cinematographic recording was performed each hour throughout 3 days during 30 s per hour. Significant differences between two kinds of sturgeons were found in the locomotor activity, trajectory of swimming, the average value and circadian rhythm of the swimming speed. The hybrid individuals swim faster and display a high peak of night activity. This puts them close to the maternal species, white sturgeon, and gives evidence of the maternal inheritance of these traits.