Temperature effects on incubation time and growth of juvenile whitefin gudgeon, Gobio albipinnatus Lukasch

Eggs of the whitefin gudgeon, Gobio albipinnatus Lukasch, were artificially obtained from adults caught in the Danube River near Vienna, Austria. Average diameter of hydrated eggs was 1.5 mm (S.D.=0.05). Incubation times decreased exponentially from 8 to 24° C. Mortality of embryos was lowest at 16° C and highest at 8° C. Total length at hatching ranged from 4 to 5.7 mm. First feeding occurred 3 days after hatching. Growth with excess food was observed for 3 months in the laboratory at 16 and 20° C. Highest growth rates obtained were 11 % fresh weight day‘. Field samples of 0+G. albipinnatus indicated four cohorts occurring in a Danube backwater. Growth in the backwater was comparable to juveniles growing at 20° C in the laboratory. From information on growth and incubation we estimate that spawning starts in the middle of May and proceeds at 2-weekly intervals until the end of June. Incubation time and growth of 0+G. albipinnatus closely resembles that of Gobio gobio (L.).