Abstract: The results of fishery biology of sturgeons Acipenser schrencki Brandt (n=155) and Huso dauricus Georgi based (n=120) collected from the middle Heilongjiang River in 2001 were summarized as follows:1) The Acipenser schrencki Brandt population had average total body length of 147.7 cm (98-232 cm),body weight 17.07 kg (3.5-62.65 kg); in Huso dauricus Georgi population, average body length was 241.11 cm (191-340 cm),and body weight 225.23 kg (24-291.0 kg). 2) Average age of the Acipenser schrencki Brandt population was 16.9 (8-29); and the average age of Huso dauricus Georgipopulation was 25.92 (14-43).3) There was an exponential function relation between body weight(W)and body length(L) for the sturgeons: W=6.9614×10~(-6)L~(2.9281). Sexual ratio of Acipenser schrencki Brandt was 1∶1.87 and that of Huso dauricus Georgi 1∶1.5. 4) Acipenser schrencki Brandt had the absolute fecundity of 46 200-1 318 350 eggs with a mean of 433 496.7 eggs, and the relative fecundity of 6 893 - 15 694 eggs/kg with a mean of (11 173.3) eggs/kg. Acipenser schrencki Brandt had an average ova diameter of 3.65 mm(3.0-4.5 mm),and average gonadosomatic indices of 22.49%. There were the absolute fecundity of 100 440-1 515 360 eggs with a mean of 1 118 732.5 eggs, and the relative fecundity of 4 377- 8 770 eggs/kg with a mean of 6 360 eggs/kg, and average gonadosomatic indices of 13.58% (11.59%-16.57%)in Huso dauricus Georgi.5) There were 620 individuals total weighing about 12 t in Acipenser schrencki breeding population and 250 individuals total weighing about 144.8 t in Huso dauricus Georgi breeding population, indicating that the number of breeding population in these populations decreased in Heilongjiang River.
2005, Vol. 20 
