Growth, the length-weight relationship, and reproduction in vimba (Vimba vimba L. 1758) sampled from an oligo-mesotrophic lake in northwest Anatolia (Turkey)

Abstract

The growth parameters and reproduction period in vimba (Vimba vimba L. 1758) sampled from Sapanca Lake were determined monthly between September 2003 and July 2004. The 335 vimba specimens caught ranged in age from 2(+) to 6(+) years, and the majority of the samples consisted of individuals of the 4(+)-year-old age group. The length-weight relationship was estimated to be W = 0.0084 FL3.1797 +/- 0.0035 for males (r(2) = 0.94, P < 0.05) and W = 0.0089 FL3.1572 +/- 0.0033 for females (r(2) = 0.93, P < 0.05). Regression coefficients for sex were significant (t-test, P < 0.05). The slope (b) significantly differed (ANCOVA, P < 0.05) between months. The fact that the b values for male and female vimba specimens differed from 3.0 indicates that there was positive allometric growth. The von Bertalanffy equation was determined using Lt = 28.940 (1-exp {-0.123[t+2.193]}), empty set': 2.030, (r = 0.999) for males and Lt = 24.708 [1-exp {-0.205[t+1.464]}), empty set': 2.097, (r = 0.999) for females. The sex ratio was 1:1.86 (chi(2); P < 0.05). The spawning period of vimba began at the end of April and continued until the beginning of July; the water temperature during this period was between 14.8 and 25.9 degrees C.