Abstract
Weight-length relationships were investigated for three fish species, i.e., Leuciscus leuciscus (L.), Phoxinus phoxinus (L.), and Salmo trutta L., which occur commonly in the Strwiąż River, a tributary of the Dniester River (Black Sea Basin). It was found that the allometric model of regression fitted the three species much better than did the isometric one in the terms of the coefficient of determination (r2). The best fitted values of parameter a (intercept) were estimated as 0.038, 0.004, and 0.008, respectively, whereas parameter b (slope) values were 2.596, 3.408, and 3.106, respectively.