CHARACTERISTICS OF THE POPULATION GROWTH AND MORTALITY OF CARP IN THE DANUBE (Km 170 – Km 196)
Daniela Cristina Gheorghe, Ionica (Bancu) Enache, V. Cristea, G.P. Razlog
The paper presents the results of the investigations made during the 2006 – 2009 period on the carp population from the Danube sector Braila (km 170) - Gropeni (km 196). During the study 367 specimens were caught, with a total biomass of 930, 25 kg.
The purpose of this study was to estimate the growth parameters and the mortality rates for the carp population.
Mathematical relationships: length – weight (L - W) and the growth equation in length von Bertalanffy (VBGF) for the carp population are: W=0.0271*Lt2.845 and Lt=87.15*(1-e-0.260(t+0.81)).
The estimated values of the mortality rates for this population are high: total mortality (Z) is 0,850 and the natural one (M) reaches the 0,370 value. Exploitation rate (E) calculated for the carp population exceeds the optimal value (0,5) which suggests that the carp population from the studied area is slightly overexploited.
Key words: Breastfeeding, bitch, chemical composition correlation