Monthly variation in sexual maturity stages
Data of monthly changes in the stages of
sexual maturity is presented in Table I. It has been
observed that part of P. latipinna population in
Wadi Haneefah stream is reproductively active
round the year. The highest reproductive activities
seem to be occurring from February to May and
August to November defining two distinct annual
period of reproduction coinciding with the period of
reduced water current and high availability of food
(Lower water level and high planktonic population
was reported by Al-Ghanim, 2005 in these months
period). An irregular pattern of distribution of
different maturity stages (I-V) was observed
(Table I).
Variations in gonado-somatic index (GSI)
The monthly changes in GSI are presented in
Figure 1. Male GSI remained lower as compared
with females. GSI started to increase from February
and attained the maximal value in May, decreased in
June corresponding to their spawning season (Table
I). The second spawning season was prolonged; it
started from August till November with the peak
value of gonado-somatic index in September