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in their sample. Calculation of the data by Minto and Nolan shows that
(1) fecundity holds a positive relation with body size (Fig. 29) but relative
fecundity, which increases to the maximum at the age of about 125+,
perceptibly decreases thereafter. The same holds true for the egg production
rate RFR as well.
Fig. 29.
Fecundity, relative fecundity and relative fecundity rate of small annual
Danio rerio
whose eggs are left uncared (A & B, compiled from Balasubramani and Pandian, 2009a),
Betta splendens
, whose eggs are guarded by male (C & D, compiled from Balasubramani and
Pandian, 2009b) and large long living
Hoplostethus atlanticus,
whose eggs are left uncared
(E & F, compiled from Minto and Nolan, 2006)
From a rare investigation undertaken on long living iteroparous
rockfi shes
Sebastes aleutianus
and
S. alutus,
de Bruin et al. (2004) recorded
the continuation of oogenesis with follicular and oocyte enlargement in
active ovaries of females even upto the age of 80 years. “Seventeen samples
of mature (> 9 years)
S. aleutianus
ranging in age from 19 to 80 years and
248 samples of mature of
S. alutus
ranging in age from 9 to 77 years were
obtained. Fortunately,
S. alutus
was sampled before spawning, when pre-
ovulatory follicles are at maximum development” (de Bruin et al., 2004).
Hence very rare and useful data have been made available for further
