Age, growth and index of production of pike (Esox lucius) from the Danube, Slovakia
1992
Cerny, J. (Slovenska Akademia Vied, Bratislava (CSFR). Ustav Zoologie a Ekosozoologie)
During the years 1985-1988, the age, growth and index of production of Esox lucius in the Danube river was recorded. Pike population consisted of 7 age categories. The age structure became balanced in 1987, when the spring outlet of young fishes (1010 reared specimens.ha-2) was done and when the river arm was connected with the innundation territory again. Considerable variability and individual differences were recorded in the growth of pike. Considered by the method of relative increase divergences, it may be characterized as mediate. The growth rate of pike in the innundation territory of the Czecho-Slovak section of the Danube is approximately the same as in its delta. The values of production index from the second to fifth age groups varied from 1308 g (Oct.1988) to 3402 g (Sept.1988). The size suitable for fishing reached in average 50 % of individuals of the third and fourth age group and 100 % of the fifth age group.
显示更多 [+] 显示较少 [-]