Age group Meannumber  ObservedLength(mm) Back calculated lengths in mm
 1  2 3   4 5 6
I 34 11.0 10.46
  II 41 15.5 10.69 14.15
III 61 18.9 11.50 15.20 17.68
I V 36 21.7 11.35 15.37 16.98 20.19
V 33 23.9 10.81 15.85 18.81 20.90 23.44
VI 12 26.4 10.75 15.34 19.52 22.02 23.69 25.36
Average total 217   10.92 15.18 18.95 21.44 23.57 25.36
Increment of length     10.92 4.26 3.77 2.49 2.13 1.79
% of annual Increment     43.1 16.88 14.87 9.82 8.40 7.06
Table 1: Average back-calculated lengths (cm) of male Siganus rivulatus from the Bitter lakes, Egypt.