Libovarsky, 1985



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Associated characteristics


Species Development state Trait Primary Data Secondary Data
Rutilus rutilus Spawning conditions Spawning temperature 14-16 15.0 °C
Rutilus rutilus Spawning conditions Spawning period duration In 1980, spawing took place between May 12 and 19. All females taken fater May 19 were spent, two of them partially spent. In 1981, the spawning began round May 12. On May 14 and 19 no famles were caught retaining all egs, two were found partially spent 1980.0 weeks
Rutilus rutilus Female Maximum GSI value No data
Rutilus rutilus Female Relative fecundity The relative number of eggs fluctuated between 241 (in 1982) and 291 (1981) eggs. The individual variability fluctuated within the range 170 to 354 eggs, the frequancy distribution was rather flat, the mode lying within the range 250 to 270 eggs 241.0 thousand eggs/kg
Rutilus rutilus Egg Oocyte diameter The modes of egg size frequencies prior to spawning varied between 1.23 and 1.32 mm. The egg diameter in the prespawning period fluctuated between 0.97 and 1.67 (up to 1.85) in fish caught in 1980 and 1981, whereas in small fish caught in 1982 the variation covered 0.88 and 1.58 mm. In other studies, the average diameter of ova prior to spawning was: 1.1, 1.16, or 1.27 1.23 mm
Rutilus rutilus Female Absolute fecundity A roach female measuring 20 cm in standard length spawned some 67 thousand eggs. The individual variation in number of eggs fluctuated between 2.6 and 184.9 thousand. [Other studies: a range of 1.4 to 26 thousands eggs in roach 7 to 16 cm in length from the lower Danube, 1 to 24 thousand eggs in roach 8 to 17 cm in length, 36 to 67 thousand eggs in roach 13 to 25 cm in length from the Klicava reservoir, and 4 to 120 thousand eggs from the Kijevskije reservoir] 20.0 thousand eggs
Rutilus rutilus Spawning conditions Spawning season In mid-May [Other authors descibed it in: last from May 11 to 22 in the Klicava reservoir, in southern Poland spawning occurred from the 3rd decade of April till the 1st decade of June] ['April', 'May', 'June']
Rutilus rutilus Female Length at sexual maturity In the lower Danube, the first mature females among two-year-old individuals of standard length 9 to 13 cm, also described as at the end of the second year of life the first mature individuals reached a length array of 135-153 mm, and 71-180 mm in the Batak reservoir 144.0 cm
Rutilus rutilus Female Age at sexual maturity The first sexually mature females were found to be aged 2 (age group III), the roach spawned after three winters of their life. [Other studies: 85% of roach females in age group II took part in spawning. Most authors however have shown that roach females spawned in age group III. Attainment of sexual maturity in age group IV for the first time was also reported, the age 3 to 4] 2.0 year