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This study was conducted to determine growth parameters, catch and fishing effort trends, stock assessment and Acceptable Biological Catch (ABC) of Caspian Sea mullets in the Iranian coastal waters of Caspian Sea in the fishing season of 2012-2013. For gathering of data on biometry and catch statistics, 5 mobile working group in the regions of Anzali, Kiashahr, Nowshahr, Babolsar and Torkmen were involved from the start to the end of fishing season.Gathered data Were entered to the computer. For data analysis, common methods were undertaken for estimation of growth parameters, mortality rates, biomass and Maximum Sustainable yield (MSY) and Acceptable Biological Catch (ABC) as well. According to the result, the number of beach seines cooperatives was 124 and fishing efforts were 45260 beach seining haul. The catch per unit of effort CPUE) was calculated 37 kg/haul during this fishing season. The total catches of Caspian Sea mullets (including illegal fishing estimated as 2151 mt. Growth parameters of golden gray mullet (Liza aurata) were estimated as K=0.12 /yr, L_∞=59.24 cm, t_0 = - 1.31 /yr. Based on catch-at-age data, in the fishing season of 2012-2013 , the total biomass, from the biomass-based cohort analysis were estimated 11321.6 mt. The reference points of F0.1 and F30% were estimated 0.3 /yr . based on these results , the fishing mortality rate in fishing season of 20122013 were very closed to these reference points. In this survey , the Maximum sustainable yield and Acceptable biological catch were estimated as 2207.7 and 1981.4 mt respectively .Results of biometry of leaping gray mullet (Liza saliens) showed that the mean length and weight of this species were 28.8 ± 3.4 cm and 230.5±74.8 g respectively. Based on these results and due to decline of golden gray mullet stocks, it is recommanded to reduce fishing effort and harvest keep to the level of MSY and ABC .The study of spawing condition of golden gray mullet in new situation of this species is also recommanded.

The Caspian Sea is an important source of water in terms of having valuable resources of sturgeon and bony fish is taken into consideration roach(Rutilus rutilus caspicus (L.)) is one of the most important commercial species in the southern coast of the Caspian Sea in Iran , the catch of this species has declined substantially in the last 10 years, The management and exploitation need of comprehensive review of its biology .This study as part of a comprehensive study of feeding , spawning and growth of this species.In this study, using samples caught in beach seine along the southern coast of the Caspian Sea coastal ( Iranian waters ) took place. The fork length and total weight ranged between 12.5 to29.5(cm) and 29 to293( grm),10.5 to23(cm) and17.2 to21(grm) in Golestan and Gilan Province respectively. The b value of the length-weight relationship ranged 3.02 to 3.25 and 3.28 to 3.75 for female and male, in Golestan and Gilan Province respectively. The age composition of the catch was from 1 to 4 year in both Province, there was one spawning peak and Fecundity variations were high and ranged 7260 to 231965 eggs. Average growth in length was described with the Von Bertalanffy growth model: L (t) = 30.94(1-exp (0.42(t-0.18) and L (t) = 20.49(1-exp (0.53(t-1). The percent of empty stomach and prey dominant evaluated during different seasons by specific formula. Result showed that gastropod, Polychaete worms and molluscs were dominated and specific food items respectively. Shrimp, fish, insects, zooplankton and clams were scare of prey. Iranian Fisheries Science Research Institute Published

This study was conducted to determine growth parameters, catch and fishing effort trends, stock assessment and Acceptable Biological Catch (ABC) of Caspian Sea mullets in the Iranian coastal waters of Caspian Sea in the fishing season of 2012-2013. For gathering of data on biometry and catch statistics, 5 mobile working group in the regions of Anzali , Kiashahr , Nowshahr , Babolsar and Torkmen were involved from the start to the end of fishing season.Gathered data Were entered to the computer. For data analysis , common methods were undertaken for estimation of growth parameters , mortality rates , biomass and Maximum Sustainable yield ( MSY ) and Acceptable Biological Catch ( ABC ) as well. . According to the result, the number of beach seines cooperatives was 124 and fishing efforts were 45260 beach seining haul . The catch per unit of effort CPUE) was calculated 37 kg/haul during this fishing season . The total catches of Caspian Sea mullets (including illegal fishing estimated as 2151 mt. Growth parameters of golden gray mullet ( Liza aurata ) were estimated as K=0.12 /yr, L∞ = 59.24 cm, t0 = - 1.31 /yr. Based on catch-at-age data, in the fishing season of 2012-2013 , the total biomass, from the biomass-based cohort analysis were estimated 11321.6 mt. The reference points of F0.1 and F30% were estimated 0.3 /yr . based on these results , the fishing mortality rate in fishing season of 20122013 were very closed to these reference points . In this survey , the Maximum sustainable yield and Acceptable biological catch were estimated as 2207.7 and 1981.4 mt respectively .Results of biometry of leaping gray mullet (Liza saliens) showed that the mean length and weight of this species were 28.8 ± 3.4 cm and 230.5 ± 74.8 g respectively . Based on these results and due to decline of golden gray mullet stocks , it is recommanded to reduce fishing effort and harvest keep to the level of MSY and ABC .The study of spawing condition of golden gray mullet in new situation of this species is also recommanded . Iranian Fisheries Science Research Institute Published

The Caspian Sea is an important source of water in terms of having valuable resources of sturgeon and bony fish is taken into consideration roach(Rutilus rutilus caspicus (L.)) is one of the most important commercial species in the southern coast of the Caspian Sea in Iran , the catch of this species has declined substantially in the last 10 years, The management and exploitation need of comprehensive review of its biology .This study as part of a comprehensive study of feeding , spawning and growth of this species.In this study, using samples caught in beach seine along the southern coast of the Caspian Sea coastal ( Iranian waters ) took place. The fork length and total weight ranged between 12.5 to29.5(cm) and 29 to293( grm),10.5 to23(cm) and17.2 to21(grm) in Golestan and Gilan Province respectively. The b value of the length-weight relationship ranged 3.02 to 3.25 and 3.28 to 3.75 for female and male, in Golestan and Gilan Province respectively. The age composition of the catch was from 1 to 4 year in both Province, there was one spawning peak and Fecundity variations were high and ranged 7260 to 231965 eggs. Average growth in length was described with the Von Bertalanffy growth model: L (t) = 30.94(1-exp (0.42(t-0.18) and L (t) = 20.49(1-exp (0.53(t-1). The percent of empty stomach and prey dominant evaluated during different seasons by specific formula. Result showed that gastropod, Polychaete worms and molluscs were dominated and specific food items respectively. Shrimp, fish, insects, zooplankton and clams were scare of prey.

The survey was conducted during 2010 and 2011 on the banana prawn stocks in Sirik to Dargahan in Strait of Hormoz. Samples was taken by bottom trawl boats monthly. Growth in the prawns (male and female) was allometric and length of maturity in female was 31.7 (mm CL). Spawning season was occurred in winter from Jan to March. Growth parameters (K, L_∞) were 1.6 y^-1 and 49 (mm CL) for female and 1.9 y^-1 and 38 (mm CL) for male respectively. Instantaneus mortality rate (M, F and Z) calculated 2.6, 1 and 3.6 y^-1 for female and 3.1, 1.4 and 4.5 y^-1 for male respectively. Banana shrimp recruited at to fishing ground in Jun and Jul. Opening time for starting catch at 2010 was calculated at 28/09/2010 and total allowable catch was 1380 tones. At 2011 starting catch was calculated at 29.09.2011 and total allowable catch was 1480 tones. Time for end of catch season were stimated at 04.11.2010 and 21.11.2011 for each year. According to yield per recruit model, the best size of the banana prawn was 30 (mm CL) for female.

The survey was conducted during 2010 and 2011 on the banana prawn stocks in Sirik to Dargahan in Strait of Hormoz. Samples was taken by bottom trawl boats monthly. Growth in the prawns (male and female) was allometric and length of maturity in female was 31.7 (mm CL). Spawning season was occurred in winter from Jan to March. Growth parameters (K, L_∞) were 1.6 y^-1 and 49 (mm CL) for female and 1.9 y^-1 and 38 (mm CL) for male respectively. Instantaneus mortality rate (M, F and Z) calculated 2.6, 1 and 3.6 y^-1 for female and 3.1, 1.4 and 4.5 y^-1 for male respectively. Banana shrimp recruited at to fishing ground in Jun and Jul. Opening time for starting catch at 2010 was calculated at 28/09/2010 and total allowable catch was 1380 tones. At 2011 starting catch was calculated at 29/09/2011 and total allowable catch was 1480 tones. Time for end of catch season were stimated at 04/11/2010 and 21/11/2011 for each year. According to yield per recruit model, the best size of the banana prawn was 30 (mm CL) for female. Iranian Fisheries Science Research Institute Published

The study of some biological aspects of Narrow-barred Spanish mackerel (Scomberomorus commerson) was done in 1380-1381 in Oman Sea (Sistan and Baluchistan province). Analysis of catch/effort statistics of Shilat Statistical system was also made for the species and Indo-pacific King mackerel (Scomberomorus guttatus) from the year 1376 to 1381 Analysis of Gonadosomatic index of the former species, indicated a protracted spawning period of March to August, with a peak in April-May. The results of hepatosomatic index indicated the highest value before the maximum of G.S.k value in May and then decreased afterwards. The sex ratio was about 1:1 during the study the basis of LM50% (94 cm) and releasing fish below 96 cm fork length, the standard mesh size of the Narrow-barred Spanish mackerel was obtained as 171 mtn (stretched mesh size). Small pelagic fish (Clupeidae) accounted for a major part of the stomach contents (47%). There is available information on _ the length—frequency -distribution-ofthe-specieSby month and gear. The proportion of the species catch has also been analyzed by fishing gear (small-mesh and larger-mesh nets). The parameters of population dynamics of the species was obtained by using length frequency data and compared to the previous studies in Indian Ocean Estimated exploitation rate of the species (E=0.81) indicated a high level result. The total landings of Narrow- barred Spanish mackerel have been increased up tol .9 times from the year 1376 to 1381 spite of decreasing the total efforts (panel.day) from 1376 to 1381 -The CPUE values of (Kg/panel.day) the species have been increased. The CPUE values of Indo-pacific king mackerel have been decreased from 1377 to 1381 as well as of decreasing the total landings (69%). Iranian Fisheries Science Research Institute Published