Some biological aspect of thinspine seacatfish (plicofollis tenuispinis) in northwest of persian gulf (Khuzestan coastal waters, Iran)

During this study from December 2009 to November 2011, 403 Thinspine seacatfish fish were caught and their weight and length were measured. Total number of caught fishes included, 33 males, 77 females and 293 immature fishes. The Mean, maximum and minimum total lengths were 236±82, 470 mm and 121 mm respectively. The Mean, maximum and minimum total weight for this species was 184±150gr, 1385 gr and 14gr respectively. The length-weight relationship were calculated as W=0.000006FL3.07 (n=77, R2= 0.98) for females, W=0.000004FL3.15 (n=33, R2=0.98) for males and W=0.000007FL3.08 (n=403, R2 =0.98) for total fishes verifying calculated b with 3, using Students t-test there was significant difference between calculated b and 3 (P < 0.05), growth pattern is allometric. The mean Values of condition factor (K) and Hepatosomatic Index (HIS) was 0/95± 0/09, 1/54± 0/2 in for total specimens. The highest value of K and HIS were observed in May, August and the lowest in December, June were observed. The mean value of Gonado somatic Index (GSI) for the total specimens were 0/89 ± 0/7. For both sexes, the highest GSI value were observed in April and the lowest GSI value in May were observed. Mean GSI value indicated that spawning time were occurred during April. The mean size at first sexual maturity (Lm) was 358mm for total fishes.