This study describes the length-weight and length-length relationships for three cyprinid species from the Bibi-Sayyedan River (western Isfahan provinces, Iran). The slope parameter (b) values in the length-weight relationship equations were determined as 3.0729 for Alburnus mossulensis Heckel, 1843; 2.8509 for Barbus lacerta Heckel, 1843; and 3.0864 for Chondrostoma regium (Heckel, 1843). This study presents the first LWR and LLR references for these species in the Bibi-Sayyedan River.

Some aspects of the reproductive biology of Planiliza abu (Mugilidae) were investigated by collecting of 428 specimens caught with trawl by local fishermen from Karun River, Ahwaz, from November 2016 to September 2017. The total length for males ranged between 10-17.1 (13.6±1.26 SD) cm and for females, between 10.5-17.3 (13.44±1.35) cm. The age range of fish in both sexes was between 0 + -7 + years and the most abundant age group was the 4 + . The sex ratio in the studied fish was equal (P>0.05). The mean egg diameter was significantly different (P<0.05) in different months and the individual size ranged between 0.12 and 0.57 mm. The absolute fecundity ranged from 3600 to 48600 eggs and the relative fecundity from 120 to 900 eggs per 1 g of body weight. The highest hepatosomatic index in females was in February during yolk vitellogenesis (1.89). Based on gonadosomatic index, egg diameter, and monthly distribution of ovarian maturation stages, the spawning season of this fish is long, but peaks in February (GSI 12.35) and March (GSI 12.18). This species appears to have a group synchrony reproductive pattern.

The feeding habits of oriental sole, Brachirus orientalis (Bloch & Schneider) were investigated using 300 male and female specimens collected from coastal waters of Bushehr Province (Persian Gulf) between June 2015 and July 2016. The total length of females and males ranged from 16.2 to 38.5 cm and 14.1 to 29.1 cm, respectively. Of the total number of stomachs examined, 225 were empty (vacuity index = 77%). This index varied significantly over the year (P < 0.05), with maximum values in April and September and minimum in October and May. The B. orientalis diet was composed of nine prey species belonging to five classes. The most important prey items were Crustacea and Mollusca (Bivalvia and Gastropoda). Diet composition showed little seasonal variation, and Crustacea, Bivalvia, and Gastropoda were the most important prey items in all seasons. Sex did not appear to have any significant effects on dietary composition, and the main prey items were consumed by both males and females (P > 0.05).

No abstract

No abstract