MORPHOLOGIC PARAMETERS AND LENGTH-MASS RELATIONSHIP OF THREE ROACH (Rutilus rutilus (L., 1758)) POPULATIONS FROM NORTHWESTERN CROATIA

Abstract

Three populations of roach from northwestern Croatia were checked for 24 morphometric and 7 meristic parameters, as well as for length-mass relationship. Some meristic characters expressed the values beyond those mentioned in the key for freshwater fish species determination in southeastern Europe. Length-mass relationship and condition factor (CF) were the highest in the river Kupa and somewhat lower in the eutrophic stagnant water (3 rd Maksimir lake). On the other hand, these parameters were significantly lower at roach from oligotrophic stagnant water (Mrtvica). This indicates that roach is similarly well adapted to the stagnant as well as running waters and that its condition and morphometry is primarily influenced by the quantity of the food offered.

Keywords

• condition factor
• length-mass relationship
• morphology
• roach
• rutilus