Short communication
FEEDING INTENSITY AND GROWTH OF SIBERIAN STURGEON ACIPENSER BAERI BRANDT IN POND CULTIVATION
Julian Pyka, Ryszard Kolman
The Stanisław Sakowicz Inland Fisheries Institute in Olsztyn, Poland
ABSTRACT. This paper presents the results of studies on the feeding and growth of Siberian sturgeon in the first year of life in monoculture in earthen ponds. The digestive tracts of the fish contained the following orders of invertebrate fauna: Cladocera, Coleoptera, Copepoda, Diptera, Heteroptera, Mollusca, Oligochaeta and Trichoptera. Diptera and Cladocera dominated. Small amounts of Copepoda, Heteroptera, Mollusca and Trichoptera were also noted. The average indexes of weight contribution reached the highest values (1.09 – 1.70 g) in the spring-summer season, while the value in the fall sample was 1.41 g. The highest values of frequency of occurrence (100%) of the dominant Cladocera and Diptera in the food and of feeding intensity (179 – 275%oo) also occurred in the spring-summer season. The highest values of the percentage indexes (> 50% - eudominants) were reported for plankton crustaceans from the order Cladocera in spring and summer. After the spring sturgeon had adapted to the new environmental conditions, a clear increase in the growth rate was observed, and after the water temperature dropped below 13°C growth stopped.
Key words: SIBERIAN STURGEON (ACIPENSER BAERI), FOOD, GROWTH, MONOCULTURE
CORRESPONDING AUTHOR:
Dr Julian Pyka, Instytut Rybactwa Śródlądowego, Zakład Ichtiologii, ul. Oczapowskiego 10, 10-719 Olsztyn;
Tel./Fax: +48 (89) 52401071; e-mail: kolrys@infish.com.pl