TWENTY-FOUR HOUR FEEDING CYCLE OF SIBERIAN STURGEON (ACIPENSER BAERI BRANDT) REARED IN A POND MONOCULTURE
Julian Pyka, Ryszard Kolman
The Stanisław Sakowicz Inland Fisheries Institute in Olsztyn, Poland
ABSTRACT. The present study evaluated the weight composition of Siberian sturgeon food, the species feeding intensity in a 24-hour cycle (as consumption index I - ‰o), and its daily food ration (as a percentage of average fish body mass). The study was conducted on fish in their first year of life which were being reared in a 0.05 ha pond with a maximum depth of 2 m and an average depth of 1.2 m. Chironomid larvae, mainly Chironomus plumosus L., were the principal food component found in the digestive tracts of all the fish in all the samples. Some butterfly and stone-fly larvae were also noted. Feeding intensity reached the highest values at night. Calculated according to Thorpe (1977), the daily food ration of Siberian sturgeon with an average body mass of 20.3 g and at an average daily water temperature of 14.2°C was 5.4% of fish body weight.
Key words: SIBERIAN STURGEON, FOOD, DAILY FOOD RATION, POND REARING