Mackay and Mann, 1969



Citation


Mackay, I. and Mann, K.H. (1969) Fecundity of two cyprinid fishes in the river Thames, Reading, England. J. Fish. Res. Board Can., pp. 2795-2805

Associated characteristics


Species Development state Trait Primary Data Secondary Data
Alburnus alburnus Spawning conditions Spawning period duration It therefore appears from the samples that the population shed a batch of eggs in early May, and that there was one, possibly two peaks of spawning activity during June No data
Rutilus rutilus Spawning conditions Spawning period duration Short spawning period No data
Rutilus rutilus Female Age at sexual maturity A proportion of the males matured at age 2+ 2.0 years
Alburnus alburnus Female Oocyte development Appereance of three kinds of eggs in the ovaries No category
Rutilus rutilus Female Oocyte development Two categories of eggs could be recognized in active ovaries at all times up to the beginning of spawning Asynchronous
Alburnus alburnus Female Absolute fecundity The estimated of a 5-year-old fish was 6356 with 95% condifidence limits at 5987 and 6776 5.0 thousand eggs
Rutilus rutilus Female Absolute fecundity Estimated fecundity of a 6-year-old fish was 5157 with 95% confidence limits 4725 and 5631 [In other studies: The average figure for Thames roach is about 5000 or 6000 eggs per fish, caspian semi-migratory roach lay in the range 34,000-51,000, whereas in the following year it had fallen to 19000 to 41000. 25.5 thousand eggs
Rutilus rutilus Female Age at sexual maturity The youngest maturing females seen were age 3+ 3.0 year
Alburnus alburnus Spawning conditions Spawning release Produced two or three batches Mutliple
Rutilus rutilus Spawning conditions Spawning release Sheld all their eggs in one batch Mutliple