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This study was conducted to determine growth parameters, catch and fishing effort trends and stock assessment of mullets in the Iranian coastal waters of Caspian Sea in the years 2015-2016 and 2016-2017. According to the result, the numbers of beach seines were 123 and 120 and their fishing efforts were observed 43588 and 42230 beach seining, respectively. The total catches (including illegal fishing) were also obtained 1542 mt and 2505 mt during 2015-2016 and 2016-2017, respectively. The mean (± SD) of fork length were observed 33.4±5.24 and 33.3±5.72 cm and for total weight were 395.8±142.8 and 395.5±264.52 g in 2015-2016 and 2016-2017, respectively. The frequency of immature individuals were observed 14.2 and 15.7 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 4 to 6 years comprised up to 75.4 and 70 percent, respectively. In fork length – weight relationship a and b were calculated 0.029 and 2.690 for 2015- 2016 and 0.0207 and 2.7914 for 2016-2017, respectively. The Growth parameters of golden gray mullet were K=0.16/yr, L∞ = 64.3 cm, t0 = -0.26/yr. The total and naturaly mortality, Z and M, were calculated 0.81 and 0.35, respectively. Based on catch-at-age data, in the years 2015-2016 and 2016-2017, the total biomass, from the biomass-based cohort analysis were estimated 8170 mt and 7960 mt for golden gray mullet, respectively. In the years 2015-2016 and 2016-2017, the instantanuse fishing mortality F, were 0.25 and 0.46 year-1 and explotation ratio were 0.46 and 0.57, respectively. 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, 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 overfishing and changing environmental following the introduction of the comb jelly Mnemiopsis leidyi in the Caspian Sea, the population structure has a strong influence on kilka fishes in the Caspian Sea and therefore to in this investigation which had been done in commercial catch regions (where discharged theirs catch) in three ports Babolsar, Amirabad (in mazandaran) and Anzali (in Guilan), stimated catch and catch per unit effort, the age structur of catch, length- weight relationship, von Bertalanffy growth parameters, condition factor, sex ratios, maturity stags, spawning and feeding. The result shown that catch of kilka in Iranian coastal in 2012 decreased from 24080 ton to 22696 ton in 2013. But CPUE increased was 2.7 ton (Vessel ×Night) and there was no significant changes. Common kilka was the predominant all months of the year, 98.1 and 98.9 percent in 2012 and 2013 respectively. The mean length was 104.4±10.5 and 101.6±11.2 at the same time and range length 92/ 5 – 117/5 mm were the dominant population(about 75%). Relative abundance of fish less than 77.5 mm and more than 127.5 mm is very low. Age abundance during this period have not been substantially changed and always fishes with 3 and 4 year olds had the highest frequency73.6 and 73.5 percent respectively. The parameters of the Von Bertalanffy growth curve were ] exp1[8.141 ) 048.1(297.0  tLt for common kilka. The instantaneous coefficient of natural mortality (M) was 0.506 yr-1. The instantaneous coefficient of fihing mortality and total mortality were 0.694 yr-1 and 1.2 yr-1 , respectively. The exploitation rate of common kilka varied during 2012-2013 between 0.41-0.50. The mean condition factor 1.41±0.14 (n=5801) and 1.38±0.16 (n=6754) at the same time respectively . According to statistical analysis Anova oneway were a significant difference between condition factor at the same time . Main prey common kilka was Acartia tonsa accounting for over 80%. It seems Common kilka due to a decrease in the frequency of other zooplankton species depend more than ever on Acartia tonsa and this species is probably a concentration of prey for Common kilka. 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

Reservoirs are one of the most constructions for control and water supply for different usage that could have various social an economical effects. The Khandaghloo dam reservoir with area of 100 ha located in Mahneshan city of Zanjan province and related to Parichay river watershed. Khandaghloo reservoir is valuable water body that the aim of its establishment was supply of water for agriculture farms. The reservoir has been studied for responsible and sustainable fisheries exploitation proposes. Results showed that the reservoir categorizes as eutroph to super eutroph based on different indices.Also phosphorous is limiting factor of the water body.Totally 42 genera from 6 phyla including green-blue algae cyanophyta, diatoms (Bacillariophyta), green algae, chlorophyta, euglenophyta, pyrrophyta and xanthophyta has been identified and cyanophyta was the dominant group that comprise 74.3 % of phytoplankton population. The zooplankton of the reservoir comprised 4 phyla and 20 genera. 1 genera of the protozoa and rhizopoda, 1 genra of the ciliophora ,15 genera of rotatoria, 2 genera of cladocera has been identified in zooplankton communities. Tubificidae and chironomidae has been identified in all months of the survey. The mean total length of crayfish was 130.5±20.5 mm ( 636) and mean weight was measured as 69.4±34.1 g with maximum and minimum weight of 1.9 and 207.2 g respectively .Total biomass of crayfish in Khandaghloo reservoir estimated as 3.4 tones with a range of 1.1–5.7 tones. But it is recommended not to harvest for at least two year due to high mortality of the populations.The fishes of the reservoir comprised common carp Chinese carp (silver carp, big head and grass carp) (released), Caspian kutum (accidentally released by fishery sector) and some endemic species as Siamahii. The catch of the reservoir fluctuated between 8 to 26 tones during 2000-2010.The fish production of Khandaghloo reservoir ranged from 167 to 324 kg/ha based on different methods that by consideration of 100 ha area of the reservoir, the total production of fish fluctuated between 16.7 to 32.4 tones. The fingerling restocking of Chinese carp in Khandaghloo reservoir with density of 1500 fingerling/ha recommended as 68% of phytoplanktonivorous fish (silver carp) ,12% zooplanktonivorous fish (big head), 6.6% of Crass carp and 10% of benthophagous fish (common carp).