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This study was conducted to determine catch and fishing effort trends, length and age composition, growth and mortality parameters and estimate biomass and acceptable biological catch of Kutum in the Iranian coastal waters of the Caspian Sea from 2015 to 2017. The catch of Kutum was 4282.9 and 3395.5 tons and CPUE were 98.3 and 80.4 kg/haul in 2015-2016 and 2016-2017, respectively. The mean (± SD) of fork length were observed 38.8±6.6 and 37.1±5.6 cm and for total weight were 790.8±435.2 and 637.2±392.2 gram in 2015-2016 and 2016-2017, respectively. The most predominated of length class was obtained 34-36 cm in 2015-2016 and from 36-38 to 38-40 cm in 2016-2017 respectively and frequency of immature individuals were observed 48.1 and 55.5 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 3 to 5 years comprised up to 76.6 percent. In length – weight relationship a, b and r2 were calculated 0.01, 3.04 and 0.96 in 2015-2016 and 0.005, 3.19 and 0.92 in 2016-2017 respectively. K value, L∞ and t 0 were calculated 0.2 (/year), 62.3 cm and -0.65 respectively. Mortality parameters such as Z, M and F were calculated 0.72, 0.37 and 0.35 respectively and Exploitation rate were calculated 0.49. The biomass of kutum estimated 25270 tons and the biomass of Kutum decreased in recently years in spite of produce and release of huge fingerlings. This recruitment (produce and release fingerlings) must be continued for stability of stocks and fishing stress must be decrease by anyway. Published

This study aimed to assess the social, economic and fish farming in cages in the Southern Caspian Sea. The Caspian Sea is considered as one of the most important water resources of Iran, in which due to the appropriate weather conditions in the north of the country, has the potential for marine aquaculture. With the implementation of this plan would say that with respect to the proposed initial selection from Kheshtsar in Mazandaran province and Kiashahr in Guilan province with along coastline of about 250 km from the depth of 20 to 100 meters and an the area of about 2027km2 has the cage aquaculture talent. Of course, at the depths of greater than 100 M by using the world technology procedure, there is also the possibility of the establishment of marine cage aquaculture. Now, with the regards of the above potential in the Caspian Sea coastline, it is expected at least 200 cages fish sites farming in with the establishment of 40 cages per site and produce 160,000 tons with creating of 1,000 direct jobs and 2,000 indirect jobs and income 2000 billion gross annual average net profit of 40% could be 800 billion in which will produce of proteins needed part of the country, creating jobs, welfare, prosperity and economy in the region. With the implementation of such national project, it is needed to establish pilot farms to reach the goals: environmental assessment studies, risk assessment, aquatic selection and the use of appropriate cage structures according to ecological conditions of southern Caspian Sea. Iranian Fisheries Science Research Institute Published

This study was conducted to determine catch and fishing effort trends, length and age composition, growth and mortality parameters and estimate biomass and acceptable biological catch of Kutum in the Iranian coastal waters of the Caspian Sea from 2015 to 2017. The catch of Kutum was 4282.9 and 3395.5 tons and CPUE were 98.3 and 80.4 kg/haul in 2015-2016 and 2016-2017, respectively. The mean (± SD) of fork length were observed 38.8±6.6 and 37.1±5.6 cm and for total weight were 790.8±435.2 and 637.2±392.2 gram in 2015-2016 and 2016- 2017, respectively. The most predominated of length class was obtained 34-36 cm in 2015-2016 and from 36-38 to 38-40 cm in 2016-2017 respectively and frequency of immature individuals were observed 48.1 and 55.5 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 3 to 5 years comprised up to 76.6 percent. In length – weight relationship a, b and r2 were calculated 0.01, 3.04 and 0.96 in 2015-2016 and 0.005, 3.19 and 0.92 in 2016-2017 respectively. K value, L∞ and t0 were calculated 0.2 (/year), 62.3 cm and -0.65 respectively. Mortality parameters such as Z, M and F were calculated 0.72, 0.37 and 0.35 respectively and Exploitation rate were calculated 0.49. The biomass of kutum estimated 25270 tons and the biomass of Kutum decreased in recently years in spite of produce and release of huge fingerlings. This recruitment (produce and release fingerlings) must be continued for stability of stocks and fishing stress must be decrease by anyway. Iranian Fisheries Science Research Institute Published

The present study was carried out on the basis of data collected from the catch of beach seine operating in the southern coast of the Caspian Sea for two species carp (Cyprinus carpio) and roach (Rutilus caspicus) in 2015 – 2016. Besides, the changes in patterns of recruitments were evaluated on the basis of the historical catch statistics and the released number of the two species which taken from the G.D office of Golestan province. The age structure and length-frequency distribution of the two species were determined. The largest catches of carp and roach belongs to the age groups (5, 6 and 1, 2) year olds, respectively. In order to estimate the growth pattern of the two species, the length-weight relationships were determined. The von Bertalanffy growth parameters (L∞, K and t0) and mortality were calculated by the ELFFAN I method using FiSAT program for two species. The von Bertalanffy growth equation obtained was Lt=75. 72 (1-e (-0. 12 (t+0. 5)) in 2015 and Lt=72. 75 (1-e (-0. 13 (t+0. 26)) in 2016 for carp and Lt=30. 82 (1-e (-0. 27 (t+1)) in 2015 Lt=24. 92 (1-e (-0. 5 (t+0. 35)) in 2016 for Roach. The estimates of von Bertalanffy growth parameters were compared with the carp populations in other areas. The total coefficient of mortality (Z) using the linear curve method of fishing was estiamted 1. 3 years for carp and 0.86 for roach in both years. The natural mortality (M) using the Pauli experimental formula was calculated 0.23 years in 2015 and 0.24 years in 2016 for carp and 0.5 years in 2015 and 0.46 years in 2016 for roach. The biomass of two species carp and roach was estimated 96.7 and 68.4 tone in 2015 and 4.8 and 21.8 tone in 2016, respectively. Iranian Fisheries Science Research Institute Published

Region South East of the Caspian Sea (area Goharbaran) having valuable resources biological flora and fauna, the diversity of commercial fishes, especially reserves the exclusive sturgeon as well as reserves abiotic such as oil and gas resources and transit of goods through Bandar Amirabad to Central Asia , the ecological conditions for the implementation of the project is very necessary. The aim of this study was to determine species composition, spatial and temporal distribution of plankton and fish of this region. Plankton sampled from different depths (5, 10 and 15 m) were carried out. Sampling of phytoplankton did by Ruttner and sampling of zooplankton did by net with mesh size 100 microns. The fish were sampled monthly from December 2013 to July 2014 and within months was carried out. From livestock gill Monofilament.. In this study, a total of 130 species of phytoplankton of 7 filums Bacillariophyta (60 species), Pyrrophyta (23 species), Cyanophyta (22 species), Chlorophyta (14 species), Euglnophyta (9 species), Haptophyta (1 species) and Chrysophyta (1 species )and 24 species of zooplankton branch of Copepoda (5 species), Rotatoria (7 species), porotozoa (3 species), Cladocera (9 species), and Meroplankton (2 species) of larvae of Cypris Balanus and bivalves Lamellibranchiate larvae and 256 fish Acipenser persicus at 5, Alosa braschnikowi 71 number, Alosa caspia 40 number, Benthophilius lipidus 1 number, Cluponella cultriventris 72 number, Cyprinus carpio 1 number, Liza saliens 15 number, Neogobius bathybius 1 number, Neogobius caspia 5 pcs, Neogobius flauviatilis 19 number, Neogobius gorlab 6 number, Rutilus kutum 14 number, Rutilus rutilus 2 pcs, vimba vimba 4 number was observed.Different ecological conditions appointment dietary needs and relationships of organisms and their adaptations to the environment, the density and distribution of different species of phytoplankton, zooplankton and fish specifies.Also the Caspian Sea due to the type of biological species and number of endemic species (42%) in addition to comb jelly invasion, were force of the effects some species like Gloeotrichia Echinulata and as a result, now or in the future, more species will be observed and recognized will be of most interest. Also Psedonitzschia seriata ability to produce Domick acid that can be hazardous to aquatic animals and even human, was in Goharbaran area. This was considered for fishes of the southern Caspian Sea and ecological distribution of most species depends on the region. The abundance of two species of whitefish and pelagic fish in Ghahrebaran region is more than the whole Caspian Sea. On the other hand, the dominant phytoplankton of this region is Bacillariophyta and dominant zooplankton is Copepoda, which shows the goodness of these plankton branches, and by changing the various factors as the different terms of receiving solar energy and resulting in temperature and water currents can cause seasonal differences in the density of the Bacillariophyta branch and also the Copepoda, therefore one of the most important factors is season, and in the winter, when the aquatic rotation of this ecosystem increases, it increases the nutrients and moves it from the floor to the water column, and as a result, increasing the amount of silica in various levels of water can affect the nutrition of fish.

Region South East of the Caspian Sea (area Goharbaran) having valuable resources biological flora and fauna, the diversity of commercial fishes, especially reserves the exclusive sturgeon as well as reserves abiotic such as oil and gas resources and transit of goods through Bandar Amirabad to Central Asia , the ecological conditions for the implementation of the project is very necessary.The aim of this study was to determine species composition, spatial and temporal distribution of plankton and fish of this region.Plankton sampled from different depths (5, 10 and 15 m) were carried out.Sampling of phytoplankton did by Ruttner and sampling of zooplankton did by net with mesh size 100 microns.The fish were sampled monthly from December 2013 to July 2014 and within months was carried out. From livestock gill Monofilament.. In this study, a total of 130 species of phytoplankton of 7 filums Bacillariophyta (60 species), Pyrrophyta (23 species), Cyanophyta (22 species), Chlorophyta (14 species), Euglnophyta (9 species), Haptophyta (1 species) and Chrysophyta (1 species )and 24 species of zooplankton branch of Copepoda (5 species), Rotatoria (7 species), porotozoa (3 species), Cladocera (9 species), and Meroplankton (2 species) of larvae of Cypris Balanus and bivalves Lamellibranchiate larvae and 256 fish Acipenser persicus at 5, Alosa braschnikowi 71 number, Alosa caspia 40 number, Benthophilius lipidus 1 number, Cluponella cultriventris 72 number, Cyprinus carpio 1 number, Liza saliens 15 number, Neogobius bathybius 1 number, Neogobius caspia 5 pcs, Neogobius flauviatilis 19 number, Neogobius gorlab 6 number, Rutilus kutum 14 number, Rutilus rutilus 2 pcs, vimba vimba 4 number was observed.Different ecological conditions appointment dietary needs and relationships of organisms and their adaptations to the environment, the density and distribution of different species of phytoplankton, zooplankton and fish specifies.Also the Caspian Sea due to the type of biological species and number of endemic species (42%) in addition to comb jelly invasion, were force of the effects some species like Gloeotrichia Echinulata and as a result, now or in the future, more species will be observed and recognized will be of most interest. Also Psedonitzschia seriata ability to produce Domick acid that can be hazardous to aquatic animals and even human, was in Goharbaran area. This was considered for fishes of the southern Caspian Sea and ecological distribution of most species depends on the region. The abundance of two species of whitefish and pelagic fish in Ghahrebaran region is more than the whole Caspian Sea. On the other hand, the dominant phytoplankton of this region is Bacillariophyta and dominant zooplankton is Copepoda, which shows the goodness of these plankton branches, and by changing the various factors as the different terms of receiving solar energy and resulting in temperature and water currents can cause seasonal differences in the density of the Bacillariophyta branch and also the Copepoda, therefore one of the most important factors is season, and in the winter, when the aquatic rotation of this ecosystem increases, it increases the nutrients and moves it from the floor to the water column, and as a result, increasing the amount of silica in various levels of water can affect the nutrition of fish. Iranian Fisheries Science Research Institute Published

The main goal of the current study is to evaluate the impact of dietary herbal appetizer on the growth performance of growth out shrimp. This project was conducted at Caspian sea research institute of ecology from 2014 to 2016. Totally 180shrimps with an average weight of 2 g were randomly distributed to 9 fiberglass tanks with area and depth of 1m2 and of 0.6 m. The experiment lasted for eight weeks and the shrimp were fed by three different diets as follows: 1. Commercial pellet contained no herbal additive (control diet) 2. Commercial pellet contained 1% herbal appetizer and 3. Commercial pellet contained 2% herbal appetizer. The results showed that prawn weight gains for diet 1 , 2 and 3 were 6.28, 5.68 and 6.07 respectively. The estimated growth rate was 2.34g for control diet, 2.22g for 1% inclusion of the additive and 2.28g for 2% inclusion of the additive. Results also showed that inclusion of the additive did not change statistically average final weight (p>0.05). A larger weight gain was observed at 0% additive inclusion although this was not statistically different with other treatments. In conclusion, with regard to the observed results, herbal appetizer administration cannot improve growth, feed conversion rate and weight gain in common carps. Iranian Fisheries Science Research Institute Published

A mass-balance Ecopath model of coastal areas in the Caspian Sea has been constructed for a quantitative description of the trophic structure of the ecosystem. The model is used to estimate the important biological parameters and relationships among the different ecologically important groups. Twenty five species were used in the present analysis. The model is based on the data collected of Kilka fisheries, beach seining (Bony fish fisheries), and set Gillnet (Sturgeon Fisheries) and also dietary information. Total landings along the Iranian portion of southern Caspian coast reached 39647 t, including sturgeon (41 t), kilka (22873 t) and bony fishes (16733 t) in 2014. Two species of kilka (Common kilka and Anchovy) are important commercially in the Caspian Sea, together accounting in the past decade for > 60 % of the total catch, as well as being a crucial part of the food chain. The mean average trophic level was estimated at 3.17 by Ecopath software. In this research, the mean level were studied between eight species varied from 2.56 to 4.04, Sander lucioperca occupy the highest and the as vimba vimba was the lowest level. The ranges of total mortality varied from 0.5 to 2.56 per years. The food consumption rate was estimated about 101.56 per year Mixd trophic level index (MTI) showed small pelagic fishes as prey, have crucial role in feeding of pelagic predators population such as invasion of the ctenophore Mnemiopsis leidyi, bream fish and benthic fish such as sturgeon. In general, niche overlap was greater in more species such as Alburnus chalcoides, Rutilus rutilus, Clupeonella cultriventris, Rutilus kutum and M. leidyi who consumed large amounts of plankton. In conclusion small pelagic fish exert a major control on the trophic dynamics of the Caspian Sea ecosystems and constitute midtrophic-level populations.

The main goal of the current study is to evaluate the impact of dietary herbal appetizer on the growth performance of growth out shrimp. This project was conducted at Caspian sea research institute of ecology from 2014 to 2016. Totally 180shrimps with an average weight of 2 g were randomly distributed to 9 fiberglass tanks with area and depth of 1m^2 and of 0.6 m. The experiment lasted for eight weeks and the shrimp were fed by three different diets as follows: 1. Commercial pellet contained no herbal additive (control diet) 2. Commercial pellet contained 1% herbal appetizer and 3. Commercial pellet contained 2% herbal appetizer. The results showed that prawn weight gains for diet 1 , 2 and 3 were 6.28, 5.68 and 6.07 respectively. The estimated growth rate was 2.34g for control diet, 2.22g for 1% inclusion of the additive and 2.28g for 2% inclusion of the additive. Results also showed that inclusion of the additive did not change statistically average final weight (p>0.05). A larger weight gain was observed at 0% additive inclusion although this was not statistically different with other treatments. In conclusion, with regard to the observed results, herbal appetizer administration cannot improve growth, feed conversion rate and weight gain in common carps.

The purpose of this study was to investigate the possibility of natural reproduction of indanger fish in the southern Caspian Sea in Tajan, Haraz,Sardabrood and Chalos rivers, and identify suitable habitats for this species in the study area as a genetic reserve.Sampling of physical and chemical parameters of water, macrobenthic invertebrates and fish fauna was conducted seasonaly in each rivers at selected stations from febrary 2010 during one year. Macrobenthic invertebrate sampling were used bySorber sampler and fish was collected by gill net and electroshocker set with a voltage of 1.7 A and 100-300 V. A total of 53 taxa of macrobenticinvertabrateshave been identified in the four mentioned rivers, in which Tajanriverconsisted of 47 taxa with highest richness.20 species of fish were determined in the studied rivers that 6 of them were non-native species.The results showed that the predominant identified fish species were native in the river. The fish species diversity increases as one moves from the headstream towards the estuaries of the two studied Sardabrud and Chalus rivers.The results of this study showed that the relative abundance of fish species resistant to pollution and hard environmental conditions were much more that sensitive species. physicochemical parameters of water such as; water temperature, DO, BOD5, pH, TSS, TDS, EC, turbidity, nutrients, biodiversity index such as Shanon index, EPT, HFBI, EPT/CHIR, nutrition functioning group and present or absent of fish species showed that there are significant decrease in water qualities from upstraem ratio to down stream (For example, in Tajan river water turbidity varied from 0 at station 1 to 333 NTU at station 6, Which is strongly influenced by sand workshops. As well as the activities of a significant impact of fish farming workshop on the Haraz river water quality). The minimum of HFBI index was 2.84 at station 1 and the maximum was recorded at station 5 with 6.01, and there is not any possibility to natural reproduction of migrated species that are dominant and indanger at downstream. Conditions for natural reproduction of this species in the rivers of srdabrood and Chalus there is to some. In Shahid- Rajaei dam the maximum relative abundance of fish species belonged to Capoeta capoeta, Luciobarbus capito and Squalius cephalus, respectively. These species have different age, length and weight stuctures at Shahid- Rajaei dam inhabitant, and the resourval of this dam and it,s upstream have been preparing auch a favorabile condition that seems there are potentioal of introductionand inhabitant of some of the Migratory and indanger fish species such as Barbels, Sturgeon, Alburnus chalcoides and etc. as genetic reserve for biodiversity preservation. Iranian Fisheries Science Research Institute Published

Mullet and mullet products have considerable economic importance at a regional level, especially around the Caspian Sea. The leaping mullet constitutes an important part of their production. This study is the first detailed work on the age and growth of the leaping mullet (Liza saliens) from September 2012 to March 2013 in theSouthern coast of the Caspian Sea.Age and growth determinations were based upon thescale samples taken from 102 fish. Marginal increment analysis was used to validate agedetermination. The back-calculated lengths stage estimated from the scale showed no differences between in this study. The maximum age of leaping mullet in the Southern coast of the Caspian Sea was 5 years for males and 6 years for females.The von Bertalanffy growth functions were Lt=30.415(1-e-0.275(t+0.645)) for males and Lt=34.832(1-e0.211(t+1.009)) for females. A large spread and length overlapcharacterized the age groups. The estimated LengthWeight relationships were common for the two sexes(W=0.079L3 ). The slope (b) values of the length-weight relationship showed that weight of leaping grey mullet in Mazandaran increased associated with length in isometric. The mean condition factor for males, females and all specimens were determined as 0.908, 0.900 and 0.897, respectively. According to sex groups, the mean condition factor of males was slightlyhigher than that of females. The total length for leaping grey mullet was determined as 23.3 cm. 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 bony fishes in the Iranian coastal waters of Caspian Sea in the years 2013-2014 and 2014-2015. According to the result, the numbers of beach seines were 124 and 120 and their fishing efforts were observed 44688 and 46299 beach seining, respectively. The total catches (including illegal fishing) were also obtained 17144.3 mt and 16733.2 mt during 2013-2014 and 2014-2015, respectively. The highest proportion of catch was belonged to kutum and golden grey mullet (94.4% and 89.5%, respectively) in two fishing seasons mentioned above. Growth parameters of kutum were estimated as K=0.19/yr, L_∞ = 61.3 cm, t0 = -0.99/yr. The Growth parameters were K=0.18/yr, L_∞ = 61.1 cm, t0 = -0.14/yr for golden gray mullet and were K=0.14/yr, L_∞ = 70.8 cm, t0 = 0/yr for common carp. Based on catch-at-age data, in the years 2013-2014 and 2014-2015, the total biomass, from the biomass-based cohort analysis were estimated 46900 mt and 41000 mt for kutum and 11550 mt and 12670 mt for golden grey mullet, respectively. The reference points of F0.1 and F35% were 0.41/yr and 0.34/yr for kutum and 0.36/yr and 0.33/yr for golden grey mullet, respectively. According to catch of species/groups, three main groups can be divided easily. The one–way ANOSIM catch similarity test indicated that coverage rates of different years were homologous and similar, but the coverage rates of different months, regions and periods were not similar. Also, there were significant differences in community composition of fishes in catch of beach seines among three times; three durations; three regions and seasons (in all cases MRPP, p

In this study genetic characterization of Barbus brachycephalus caspius, Lucioperca lucioperca , Rutilus rutilus caspius , Rutilus frisi kutum and Salmo trutta caspius were examined by 611 samples from regions in East (Guilan province), Middle (Mazandaran province) and west (Golestan province) of southen part of the Caspian Sea. DNA was extracted from fin tissue by phenol - chlorophorm method and then PCR was performed using special primers. Statistical analysis of data was performed by Gene Alex, MEGA and Arlequin softwares. - Rutilus frisi kutum: The results showed that nine of ten primers were polymorphic loci. The mean of effective and observed alleles were 7.26±0.49 and 4.37± 0.35 respectively. Also, the mean of expected and observed heterozygosity were 0.55±0.03 and 0.69±0.02 respectively. Of the analysed loci, all of the samples (except Tajan and samples in LOC4 and Gilan samples in MFW2) possible tests were found to deviate significantly from the Hardy–Weinberg equilibrium(P

The ichthyology studies at fish tagging was referred to more than 100 years ago. Tagging is utilized for the estimation of stock amount, population frequency and project or calculating of survival and growth value. There are many various methods for fish tagging are used for juvenile to adult fish. The current study was carried out at Ghare-su research station during 2011-2013. 250 of carp fingerlings (Cyprinus carpio) were tagged by bath with tetracycline manner (pH=6, 500mg/l). The fork length and weight of fish were 10-12 mm and 2-4 g, respectively. Also, fish were fed twice a day. The second and third tagging stages were performed at November 2012 and July 2014, respectively. After otolith was extracted, it was washed water and dry at lab room air. The tagged rings or loops (annuali) were observed by lab loupe with 10X and 40 X magnifications. The results showed that a narrow band was formed after the first tagging of carp fingerlings, as it was seen at the end of otolith edge. It was demonstrated that tetracycline was absorbed and the tagged ring or loop (annuli) was newly formed at external or out of othlith edge. There was not observed any fish death, when carp fingerlings were tagged by OTC bath manner. It said that the first OTC band will be seen, the first sign of the formed OTC band was observed at external margin of otoilith after 6th month , of course , from 4th month, this sign was formed at the most external of otoilth edge but with added the following region, it can be hardly distinguished. The formed band in relative to second tagging was similar to the first band but there was no discrepancy or difference with together.

The main goal of the current study is to evaluate the impact of dietary herbal appetizer on the growth performance of growth out common carp. This project was conducted at Caspian sea research institute of ecology from 2013 to 2014. Totally 186 common carps with an average weight of 126.3 g were randomly distributed to 9 fiberglass tanks with area and depth of 16m2 and of 0.6 m. The experiment lasted for eight weeks and the fish were fed by three different diets as follows: 1. Commercial pellet contained no herbal additive (control diet) 2. Commercial pellet contained 1% herbal appetizer and 3. Commercial pellet contained 2% herbal appetizer. The results showed that common carp weight gains for diet 1 , 2 and 3 were 51.6, 49.3 and 57.6g respectively. The estimated growth rate was 39.03g for control diet, 40.03g for 1% inclusion of the additive and 48.65g for 2% inclusion of the additive. Results also showed that inclusion of the additive did not change statistically average final weight (p>0.05). A larger weight gain was observed at 2% additive inclusion although this was not statistically different with other treatments. In conclusion, with regard to the observed results, herbal appetizer administration cannot improve growth, feed conversion rate and weight gain in common carps.

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 purpose of this study was to investigate the possibility of natural reproduction of indanger fish in the southern Caspian Sea in Tajan, Haraz,Sardabrood and Chalos rivers, and identify suitable habitats for this species in the study area as a genetic reserve.Sampling of physical and chemical parameters of water, macrobenthic invertebrates and fish fauna was conducted seasonaly in each rivers at selected stations from febrary 2010 during one year. Macrobenthic invertebrate sampling were used bySorber sampler and fish was collected by gill net and electroshocker set with a voltage of 1.7 A and 100-300 V. A total of 53 taxa of macrobenticinvertabrateshave been identified in the four mentioned rivers, in which Tajanriverconsisted of 47 taxa with highest richness.20 species of fish were determined in the studied rivers that 6 of them were non-native species.The results showed that the predominant identified fish species were native in the river. The fish species diversity increases as one moves from the headstream towards the estuaries of the two studied Sardabrud and Chalus rivers.The results of this study showed that the relative abundance of fish species resistant to pollution and hard environmental conditions were much more that sensitive species. physicochemical parameters of water such as; water temperature, DO, BOD5, pH, TSS, TDS, EC, turbidity, nutrients, biodiversity index such as Shanon index, EPT, HFBI, EPT/CHIR, nutrition functioning group and present or absent of fish species showed that there are significant decrease in water qualities from upstraem ratio to down stream (For example, in Tajan river water turbidity varied from 0 at station 1 to 333 NTU at station 6, Which is strongly influenced by sand workshops. As well as the activities of a significant impact of fish farming workshop on the Haraz river water quality). The minimum of HFBI index was 2.84 at station 1 and the maximum was recorded at station 5 with 6.01, and there is not any possibility to natural reproduction of migrated species that are dominant and indanger at downstream. Conditions for natural reproduction of this species in the rivers of srdabrood and Chalus there is to some. In Shahid- Rajaei dam the maximum relative abundance of fish species belonged to Capoeta capoeta, Luciobarbus capito and Squalius cephalus, respectively. These species have different age, length and weight stuctures at Shahid- Rajaei dam inhabitant, and the resourval of this dam and it,s upstream have been preparing auch a favorabile condition that seems there are potentioal of introductionand inhabitant of some of the Migratory and indanger fish species such as Barbels, Sturgeon, Alburnus chalcoides and etc. as genetic reserve for biodiversity preservation.

The aim of this project is to study the growth and age structure in the Caspian trout, comparison with other coldwater species and check the trend of these parameters in recent years. This study was conducted during 2013 till 2015. Totally, 43 specimens for back calculation and 101 specimens for biometrical study of the Caspian trout have been caught in two month period. Biometric parameters such as length, weight and age of the fish were recorded. Base on Back calculation method in 1393, the average length of fish at ages 1, 2 and 3 years old were 18.98 ± 3.5, 30.5 ± 7.24 and 41.7 ± 9.1 cm. So these age groups are under the adult age and don’t approaching to near the beach and rivers for spawning behavior. Therefore, these length groups cannot be observed in catch composition. The result showed, the mean of gonad weight in this fish was about 11 percent of total weight and number of eggs per gram of gonad calculated about 10.8 numbers. Minimum age and maximum age of this species determined 4 years and 7 years (mean = 5.6) and the most frequency allocated to 5 age group and the frequency of 6 and 7 years has been remarkable. The average length of salmon was 69.2 ± 6.2 cm (minimum 57 and maximum 81 cm) and the average weight was measured 3323 ± 677 g (2400 to 5600 g) in the catch composition. Growth parameters such as k, L∞ and ø’ was measured 0.18, 104 cm and 3.289 respectively. The amount of b for relation length and weight was 2.9 which imply negative allometry. L∞ and growth coefficient (K) on the Caspian trout were acceptable range, that it shows good growth the fish in the sea water. Most of the fishes were catched from Cheshmehkileh River. As at present Shilat uses just the broods of the Tonekaboon region for restocking of this species, we recommend using the broods of the western region separately for rehabilitation of the stocks of this region. 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 bony fishes in the Iranian coastal waters of Caspian Sea in the years 2013-2014 and 2014-2015. According to the result, the numbers of beach seines were 124 and 120 and their fishing efforts were observed 44688 and 46299 beach seining, respectively. The total catches (including illegal fishing) were also obtained 17144.3 mt and 16733.2 mt during 2013-2014 and 2014-2015, respectively. The highest proportion of catch was belonged to kutum and golden grey mullet (94.4% and 89.5%, respectively) in two fishing seasons mentioned above. Growth parameters of kutum were estimated as K=0.19/yr, L_∞ =61.3 cm, t0=-0.99/yr. The Growth parameters were K=0.18/yr, L_∞= 61.1 cm, t0= -0.14/yr for golden gray mullet and were K=0.14/yr, L_∞= 70.8 cm, t0= 0/yr for common carp. Based on catch-at-age data, in the years 2013-2014 and 2014-2015, the total biomass, from the biomass-based cohort analysis were estimated 46900 mt and 41000 mt for kutum and 11550 mt and 12670 mt for golden grey mullet, respectively. The reference points of F0.1 and F35% were 0.41/yr and 0.34/yr for kutum and 0.36/yr and 0.33/yr for golden grey mullet, respectively. According to catch of species/groups, three main groups can be divided easily. The one–way ANOSIM catch similarity test indicated that coverage rates of different years were homologous and similar, but the coverage rates of different months, regions and periods were not similar. Also, there were significant differences in community composition of fishes in catch of beach seines among three times; three durations; three regions and seasons (in all cases MRPP, p

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

The ichthyology studies at fish tagging was referred to more than 100 years ago. Tagging is utilized for the estimation of stock amount, population frequency and project or calculating of survival and growth value. There are many various methods for fish tagging are used for juvenile to adult fish. The current study was carried out at Ghare-su research station during 2011-2013. 250 of carp fingerlings (Cyprinus carpio ) were tagged by bath with tetracycline manner (pH=6, 500mg/l). The fork length and weight of fish were 10-12 mm and 2-4 g, respectively. Also, fish were fed twice a day. The second and third tagging stages were performed at November 2012 and July 2014, respectively. After otolith was extracted, it was washed water and dry at lab room air. The tagged rings or loops (annuali) were observed by lab loupe with 10X and 40 X magnifications. The results showed that a narrow band was formed after the first tagging of carp fingerlings, as it was seen at the end of otolith edge. It was demonstrated that tetracycline was absorbed and the tagged ring or loop (annuli) was newly formed at external or out of othlith edge. There was not observed any fish death, when carp fingerlings were tagged by OTC bath manner. It said that the first OTC band will be seen, the first sign of the formed OTC band was observed at external margin of otoilith after 6th month , of course , from 4th month, this sign was formed at the most external of otoilth edge but with added the following region, it can be hardly distinguished. The formed band in relative to second tagging was similar to the first band but there was no discrepancy or difference with together. Iranian Fisheries Science Research Institute Published

The main objectives of the present study were to estimate of biomass and maximum sustainable yield of common kilka in Iranian waters of the Caspian Sea. This paper examines the maximum sustainable yield (MSY) and fishing intensity at MSY (fMSY) and then using by fMSY, yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of Fmax, F0.1 and F40%; the acceptable biological catch (ABC) was estimated. The results showed that the catch of three species of kilka were 24080 and 22969 t in 2012-2013 and 2013-2014 in Iranian waters of the Caspian sea, respectively and common kilka predominated with 98.1% and 98.9%, respectively. Growth parameters were estimated as L∞ = 141.8 mm, K=0.297 year−1 , t0 =−1.048 year−1 . The ages of common kilka comprised 6 age groups, ranged from 1 to 6 years and Age groups 3 and 4 years old had the highest frequency. In the years 2012-2013, the catch of age 1 and age 4 represented the lowest and highest proportion of total catch (133.6 and 9121.6 t). In 2013-2014, followed the catch of age 1 and age 3 had the lowest and highest proportion of total catch (151.9 and 8700.2 t). The instantaneous coefficient of natural mortality was estimated as 0.506 year−1 and total mortality and the instantaneous coefficient of terminal fishing mortality were 0.894 and 1.40 year−1 respectively. In the years 2012-2013 and 2013-2014, the biomass of common kilka was estimated 90700 and 83300 t, respectively. Also, the fishing mortality was 0.622 and 0.894 year−1 and the exploration rates were 0.551 and 0.636. The reference points of common kilka at F0.1 and F40% were estimated 0.92 and 0.80 year−1 , respectively. According to Schafer model the MSY and fMSY were estimated 22670 t and 8690 vessel×nights (a unit of effort). In 2013-2014, the ABC of common kilka was estimated 17500, 20060, 23500 and 18900 t in tiers 2, 3, 4 and 5, respectively. However, for the implementation of a precautionary management approach the lower and more accurate ABC-value, based on more information, should be selected and thus the catch should be restricted to 17500 t. Iranian Fisheries Science Research Institute Published

The main objectives of the present study were to estimate of biomass and maximum sustainable yield of common kilka in Iranian waters of the Caspian Sea. This paper examines the maximum sustainable yield (MSY) and fishing intensity at MSY (fMSY) and then using by fMSY, yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of Fmax, F0.1 and F40%; the acceptable biological catch (ABC) was estimated. The results showed that the catch of three species of kilka were 24080 and 22969 t in 2012-2013 and 2013-2014 in Iranian waters of the Caspian sea, respectively and common kilka predominated with 98.1% and 98.9%, respectively. Growth parameters were estimated as L_∞=141.8 mm, K=0.297 yea^r−1, t_0=−1.048 year^−1. The ages of common kilka comprised 6 age groups, ranged from 1 to 6 years and Age groups 3 and 4 years old had the highest frequency. In the years 2012-2013, the catch of age 1 and age 4 represented the lowest and highest proportion of total catch (133.6 and 9121.6 t). In 2013-2014, followed the catch of age 1 and age 3 had the lowest and highest proportion of total catch (151.9 and 8700.2 t). The instantaneous coefficient of natural mortality was estimated as 0.506 year^−1 and total mortality and the instantaneous coefficient of terminal fishing mortality were 0.894 and 1.40 year^−1 respectively. In the years 2012-2013 and 2013-2014, the biomass of common kilka was estimated 90700 and 83300 t, respectively. Also, the fishing mortality was 0.622 and 0.894 year^−1 and the exploration rates were 0.551 and 0.636. The reference points of common kilka at F0.1 and F40% were estimated 0.92 and 0.80 year^−1, respectively. According to Schafer model the MSY and fMSY were estimated 22670 t and 8690 vessel×nights (a unit of effort). In 2013-2014, the ABC of common kilka was estimated 17500, 20060, 23500 and 18900 t in tiers 2, 3, 4 and 5, respectively. However, for the implementation of a precautionary management approach the lower and more accurate ABC-value, based on more information, should be selected and thus the catch should be restricted to 17500 t.

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

Mullet and mullet products have considerable economic importance at a regional level, especially around the Caspian Sea. The leaping mullet constitutes an important part of their production. This study is the first detailed work on the age and growth of the leaping mullet (Liza saliens) from September 2012 to March 2013 in the Southern coast of the Caspian Sea. Age and growth determinations were based upon the scale samples taken from 102 fish. Marginal increment analysis was used to validate age determination. The back-calculated lengths stage estimated from the scale showed no differences between in this study. The maximum age of leaping mullet in the Southern coast of the Caspian Sea was 5 years for males and 6 years for females. The von Bertalanffy growth functions were Lt=30.415(1-e-0.275(t+0.645)) for males and Lt=34.832(1-e 0.211(t+1.009)) for females. A large spread and length overlap characterized the age groups. The estimated Length Weight relationships were common for the two sexes (W=0.079L3 ). The slope (b) values of the length-weight relationship showed that weight of leaping grey mullet in Mazandaran increased associated with length in isometric. The mean condition factor for males, females and all specimens were determined as 0.908, 0.900 and 0.897, respectively. According to sex groups, the mean condition factor of males was slightlyhigher than that of females. The total length for leaping grey mullet was determined as 23.3 cm.

In this study genetic characterization of Barbus brachycephalus caspius, Lucioperca lucioperca, Rutilus rutilus caspius, Rutilus frisi kutum and Salmo trutta caspius were examined by 611 samples from regions in East (Guilan province), Middle (Mazandaran province) and west (Golestan province) of southen part of the Caspian Sea. DNA was extracted from fin tissue by phenol -chlorophorm method and then PCR was performed using special primers. Statistical analysis of data was performed by Gene Alex, MEGA and Arlequin softwares. -Rutilus frisi kutum: The results showed that nine of ten primers were polymorphic loci. The mean of effective and observed alleles were 7.26±0.49 and 4.37±0.35 respectively. Also, the mean of expected and observed heterozygosity were 0.55±0.03 and 0.69±0.02 respectively Of the analysed loci, all of the samples (except Tajan and samples in LOC4 and Gilan samples in MFW2) possible tests were found to deviate significantly from the Hardy–Weinberg equilibrium (P

The main goal of the current study is to evaluate the impact of dietary herbal appetizer on the growth performance of growth out common carp. This project was conducted at Caspian sea research institute of ecology from 2013 to 2014. Totally 186 common carps with an average weight of 126.3 g were randomly distributed to 9 fiberglass tanks with area and depth of 16m2 and of 0.6 m. The experiment lasted for eight weeks and the fish were fed by three different diets as follows: 1. Commercial pellet contained no herbal additive (control diet) 2. Commercial pellet contained 1% herbal appetizer and 3. Commercial pellet contained 2% herbal appetizer. The results showed that common carp weight gains for diet 1 , 2 and 3 were 51.6, 49.3 and 57.6g respectively. The estimated growth rate was 39.03g for control diet, 40.03g for 1% inclusion of the additive and 48.65g for 2% inclusion of the additive. Results also showed that inclusion of the additive did not change statistically average final weight (p>0.05). A larger weight gain was observed at 2% additive inclusion although this was not statistically different with other treatments. In conclusion, with regard to the observed results, herbal appetizer administration cannot improve growth, feed conversion rate and weight gain in common carps. Iranian Fisheries Science Research Institute Published

The aim of this project is to study the growth and age structure in the Caspian trout, comparison with other coldwater species and check the trend of these parameters in recent years. This study was conducted during 2013 till 2015. Totally, 43 specimens for back calculation and 101 specimens for biometrical study of the Caspian trout have been caught in two month period. Biometric parameters such as length, weight and age of the fish were recorded. Base on Back calculation method in 1393, the average length of fish at ages 1, 2 and 3 years old were 18.98 ± 3.5, 30.5 ± 7.24 and 41.7 ± 9.1 cm. So these age groups are under the adult age and don’t approaching to near the beach and rivers for spawning behavior. Therefore, these length groups cannot be observed in catch composition. The result showed, the mean of gonad weight in this fish was about 11 percent of total weight and number of eggs per gram of gonad calculated about 10.8 numbers. Minimum age and maximum age of this species determined 4 years and 7 years (mean = 5.6) and the most frequency allocated to 5 age group and the frequency of 6 and 7 years has been remarkable. The average length of salmon was 69.2 ± 6.2 cm (minimum 57 and maximum 81 cm) and the average weight was measured 3323 ± 677 g (2400 to 5600 g) in the catch composition. Growth parameters such as k, L_∞ and ø’ was measured 0.18, 104 cm and 3.289 respectively. The amount of b for relation length and weight was 2.9 which imply negative allometry. L_∞ and growth coefficient (K) on the Caspian trout were acceptable range, that it shows good growth the fish in the sea water. Most of the fishes were catched from Cheshmehkileh River. As at present Shilat uses just the broods of the Tonekaboon region for restocking of this species, we recommend using the broods of the western region separately for rehabilitation of the stocks of this region.

After the arrival of the invasive spexies (Mnemiopsis leidyi) in the ecosystem of Caspian Sea in 1999, It had notable impacts. In this study, we,re assessing impacts of quantitative M. leidyi as a biopllutant on zooplankton community in the southern part of the Caspian Sea during 2001-2010 period. It becomes clear that Abundance and Distribution Range ( ADR) of M.leidyi during 2001-2009 was in class E( occurrence in high numbers in all localities) and in year 2010 was in class D( occurrence in moderate numbers in all localities). from 2001- 2009, ADR in Summer season was in class E, but in summer 2010 , relatinve biomass of M.leidyi has decreased and ADR was evaluated as D. During the fall seasons of 2001 -2010, only in fall of 2003 and 2010, the ADR was C( occurrence in low numbers in all localities) and D respectively and in other years, the ADR was in class E. In winter season relative biomass of M.leidyi decreased and only in winter of 2001 relative biomass was high and the highest ADR ( class E). In winter 2003 and 2004, ADR was in class D . The biomass of M.leidyi was found to be zero in winter 2008. From winter of 2009-2010,ADR, were assessed B and A respectively. In the spring, ADR was evaluated A and D. Considering the obtained results, the yesr 2001, which the relative niomass was more than 90 percent,could be considered as the expantion phase and the following years( 2002-2010) with regard to decrease of relative biomass as the adjustment phase. With regards to the loss of the keystone species (Eurytemora sP.) and some other native species ,our evalution showed that the impact of M.leidyi on structure of zooplankton community was assessed as massive (C4).During summer and fall seasons that biomass of M.leidyi was higher than 50%, only A.tonsa exist, but during spring and winter seasons that biomass of M.leidyi was decreased and more species have a chance to exist. Iranian Fisheries Science Research Institute Published

Present study analyzed the stomach contents of individuals belonging to five fish’s species in order toInvestigate seasonal changes in feeding strategy and diet composition in the South coast of the Caspian Sea (Gilan and Mazandaran provinces) from late March until late May 2010 using the research ship Gillan and fishing with batoom trawl nets and fishing blades insoles bony fishes in the depths of less than 60 meters. The average length and the total weight of Rutilus frisii kutum, Rutilus rutilus caspicus, Cyprinus carpio, Liza auratus and Liza saliens respectively were 36/9 ± 8/5 cm , 562/9 ± 353/2 g, 23/2 ± 3/2 cm , 202 ± 101/6 g, 24/6 ± 8/1 cm , 249/8 ± 242 g, 32/2 ± 8/9 cm , 320/9 ± 242/8 g, 22/7 ± 2/6 cm and 82/9 ± 52/2 g repectively. Using the method of Shorygin and Costello highly nourishing food strategy and different species of fishes were studied. The results of this study showed that Rutilus frisii kutum fed generally of Balanus and Cerastorderma In order of importance after Bivalvia, Gastropoda, Crabs, Fish eggs, Filamentous alge in GI Rutilus frisii kutum presence, but feeding it of Bivalvia (in particular Cerastorderma) was much more than the other food. The results of present study showed that under the influence of compatibility and behavioral mechanisms, ecological, physiological and nutritional importance of Rutilus frisii kutum Bivalvia. The results of studies were showed that Bivalvia was feeding the dominant Rutilus frisii kutum , while the results of this study showed that despite Bivalvia present importance in feeding the of this species, it seems that its presence in such digestion decreased. As well as the dominant food of Rutilus rutilus caspicus was fish, but generally from Detrite fed. This study showed that feeding the dominant species of Cyprinus carpio, Liza auratus and Liza saliens of Detrite was. The most important food items after ditrit for the Cyprinus carpio in order of importance include the Bivalvia, Gastropoda, Oligochaeta, Abra ovata, Nereis, Fish eggs, Filamentous alge, was. The Liza auratus dietary habits also showed that after ditrit the most importance in nutrition related to Foraminifera, Porifera and Balanus, and for Liza saliens to Gastropoda, Bivalvia and Porifera. The results showed that the mullet the greater the intensity of feeding fishes than other species were, Rutilus frisii kutum in between of Cyprinidae the greater the intensity of feeding fishes than other species were (0/05 > P). The values of this indicator in the lower longitudinal in all fish species investigated were more than high longitudinal groups. The feeding intensity at different times of sampling for all species investigated showed that in all species at times extremely reduced the reproductive index (0/05 > P). As well as the diversity foods in the lower longitudinal in all fish species investigated were more than high longitudinal groups. In conclution, our results demonstrated Food strategy have changed based on physiological changes, metabolismi activity, behaviour, and the amount of food available. Iranian Fisheries Science Research Institute Published

This study was to assess the silver carp diet compositionduring grow out period. The experiment was conducted in a well-managed fish farm located at Mazndarn province from 2012 to 2013. Totally five samples from the pond water and also silver cap intestines were collected in May, April, Jun, July, August and September of 2012. The results showed that there are five phyla of phytoplankton in the ponds including: Phyrophyta, Bacilluryophyta, Cyanophyta, Clorophyta, Oglenophyta. A comparison of phytoplankton populationindicated a significant differences throughout the five sampling sessions (P

Present study analyzed the stomach contents of individuals belonging to five fish’s species in order toInvestigate seasonal changes in feeding strategy and diet composition in the South coast of the Caspian Sea (Gilan and Mazandaran provinces) from late March until late May 2010 using the research ship Gillan and fishing with batoom trawl nets and fishing blades insoles bony fishes in the depths of less than 60 meters. The average length and the total weight of Rutilus frisii kutum, Rutilus rutilus caspicus, Cyprinus carpio, Liza auratus and Liza saliens respectively were 36/9 ± 8/5 cm , 562/9 ± 353/2 g, 23/2 ± 3/2 cm , 202 ± 101/6 g, 24/6 ± 8/1 cm , 249/8 ± 242 g, 32/2 ± 8/9 cm , 320/9 ± 242/8 g, 22/7 ± 2/6 cm and 82/9 ± 52/2 g repectively. Using the method of Shorygin and Costello highly nourishing food strategy and different species of fishes were studied. The results of this study showed that Rutilus frisii kutum fed generally of Balanus and Cerastorderma In order of importance after Bivalvia, Gastropoda, Crabs, Fish eggs, Filamentous alge in GI Rutilus frisii kutum presence, but feeding it of Bivalvia (in particular Cerastorderma) was much more than the other food. The results of present study showed that under the influence of compatibility and behavioral mechanisms, ecological, physiological and nutritional importance of Rutilus frisii kutum Bivalvia. The results of studies were showed that Bivalvia was feeding the dominant Rutilus frisii kutum , while the results of this study showed that despite Bivalvia present importance in feeding the of this species, it seems that its presence in such digestion decreased. As well as the dominant food of Rutilus rutilus caspicus was fish, but generally from Detrite fed. This study showed that feeding the dominant species of Cyprinus carpio, Liza auratus and Liza saliens of Detrite was. The most important food items after ditrit for the Cyprinus carpio in order of importance include the Bivalvia, Gastropoda, Oligochaeta, Abra ovata, Nereis, Fish eggs, Filamentous alge, was. The Liza auratus dietary habits also showed that after ditrit the most importance in nutrition related to Foraminifera, Porifera and Balanus, and for Liza saliens to Gastropoda, Bivalvia and Porifera. The results showed that the mullet the greater the intensity of feeding fishes than other species were, Rutilus frisii kutum in between of Cyprinidae the greater the intensity of feeding fishes than other species were (0/05 > P). The values of this indicator in the lower longitudinal in all fish species investigated were more than high longitudinal groups. The feeding intensity at different times of sampling for all species investigated showed that in all species at times extremely reduced the reproductive index (0/05 > P). As well as the diversity foods in the lower longitudinal in all fish species investigated were more than high longitudinal groups. In conclusion, our results demonstrated Food strategy have changed based on physiological changes, metabolism activity, behaviour, and the amount of food available.

This study was to assess the silver carp diet compositionduring grow out period. The experiment was conducted in a well-managed fish farm located at Mazndarn province from 2012 to 2013. Totally five samples from the pond water and also silver cap intestines were collected in May, April, Jun, July, August and September of 2012. The results showed that there are five phyla of phytoplankton in the ponds including: Phyrophyta, Bacilluryophyta, Cyanophyta, Clorophyta, Oglenophyta. A comparison of phytoplankton populationindicated a significant differences throughout the five sampling sessions (P

This study was to investigate the possibility of pellet production for grow out common carp considering attractiveness and stability of the pellets. The experiment consisted of two periods and was conducted at the Caspian Sea ecology research center in 2011 and 2012. In period one, two types of pellet with similar protein level (31%) and different energy contents (3000 and 3500 cal/g) were formulated by the ingredients used in fish feed industry. In period two, 316 juvenile carp with initial weight of 27.9g were assigned randomly to 9 fiberglass tanks (4×4×1 m), with three replicates for each treatment. The fish were fed by three diets throughout the eight weeks study , two diets were formulated in the current study and third one was a commercial carp diet with 25% protein. The results showed that feeding with diet containing 31% protein and 3500 cal/g energy led to a feed conversion ratio of 3, but this value was recorded 1.9 for commercial diet. The type of diets was also influenced (P

This study was to investigate the possibility of pellet production for grow out common carp considering attractiveness and stability of the pellets. The experiment consisted of two periods and was conducted at the Caspian Sea ecology research center in 2011 and 2012. In period one, two types of pellet with similar protein level (31%) and different energy contents (3000 and 3500 cal/g) were formulated by the ingredients used in fish feed industry. In period two, 316 juvenile carp with initial weight of 27.9g were assigned randomly to 9 fiberglass tanks (4×4×1 m), with three replicates for each treatment. The fish were fed by three diets throughout the eight weeks study, two diets were formulated in the current study and third one was a commercial carp diet with 25% protein. The results showed that feeding with diet containing 31% protein and 3500 cal/g energy led to a feed conversion ratio of 3, but this value was recorded 1.9 for commercial diet. The type of diets was also influenced (P

The beach seines catch and effort data from 1996 to 2011 categorized in four periods and used in this research. Geographical coordinates of beach seines determined by portable GPS and distribution maps of important and commercial species prepared by catch per unit effort (CPUE). The concentration of beach seines in the western coast of Golestan province, Kiashahr area and eastern part of Anzali was more than another part. The daily effort in Kiashahr and Anzali area was very high, thus the fishing stress in these areas was more than another part of Iranian coastal waters of the Caspian Sea. The number of species in catch composition increased from east to west and the beach seines of Guilan province had total of commercial species, but the number of commercial species rarely was five species in Golestan province and especially in eastern coast. Relative frequency and distribution of Kuttum in the east Babolsar area and then between Sepidroud and Anzali lagoon were more than another part. The ISI index of Kuttum was high in all of the area except east coast of Golestan province. The main distribution of Mullets determined in the western coast of Golestan province and the Amirabad fishing area and in these areas, the ISI index of Mullets was high. The main distribution area of common carp determined in east coast of Golestan and the ISI index of common carp was very low in other parts. Density and distribution of Kolmeh were high in eastern and western coasts of Iranian waters of the Caspian Sea and the density of this species was very low in Mazandaran province. The density of Zander was very high in surrounding of Sepidroud River and Anzali lagoon. The ISI index of commercial species in Guilan province was more than other provinces except Kuttum, mullets and common carp. Iranian Fisheries Science Research Institute Published

The project of the Study on fishing and resource management of fisheries within Southern Caspian Sea was conducted on the base of an agreement made between fisheries organization (Shilat) and the Iranian fishery research organization (IFRO) signed in 2010. In this library-based study the current situation of bony fish fisheries and biology of these species has been surveyed in Iranian waters of the Caspian Sea . In this survey internal and external environmental factors of bony fishes activities were considered. Using SWOT analysis method, current situation of fisheries was investigated..One of the most important strategies for conserving anadromous species such as Caspian kutum , common carp, roach, bream and …. is rehabilitation of the natural spawning ground in rivers, coastal lagoon specially Anzali lagoon .By conducting this strategy not only restocks of bony fishes is done ,but also reduced the cost of artificial restocking programs and releasing fingerlings .In short term , it is nessesary to enhance the stocks of the species that have low catch is done by huge releasing of the fingerlings and study the qualification of the program.

The beach seines catch and effort data from 1996 to 2011 categorized in four periods and used in this research. Geographical coordinates of beach seines determined by portable GPS and distribution maps of important and commercial species prepared by catch per unit effort (CPUE). The concentration of beach seines in the western coast of Golestan province, Kiashahr area and eastern part of Anzali was more than another part. The daily effort in Kiashahr and Anzali area was very high, thus the fishing stress in these areas was more than another part of Iranian coastal waters of the Caspian Sea. The number of species in catch composition increased from east to west and the beach seines of Guilan province had total of commercial species, but the number of commercial species rarely was five species in Golestan province and especially in eastern coast. Relative frequency and distribution of Kuttum in the east Babolsar area and then between Sepidroud and Anzali lagoon were more than another part. The ISI index of Kuttum was high in all of the area except east coast of Golestan province. The main distribution of Mullets determined in the western coast of Golestan province and the Amirabad fishing area and in these areas, the ISI index of Mullets was high. The main distribution area of common carp determined in east coast of Golestan and the ISI index of common carp was very low in other parts. Density and distribution of Kolmeh were high in eastern and western coasts of Iranian waters of the Caspian Sea and the density of this species was very low in Mazandaran province. The density of Zander was very high in surrounding of Sepidroud River and Anzali lagoon. The ISI index of commercial species in Guilan province was more than other provinces except Kuttum, mullets and common carp.

The project of the Study on fishing and resource management of fisheries within Southern Caspian Sea was conducted on the base of an agreement made between fisheries organization (Shilat) and the Iranian fishery research organization (IFRO) signed in 2010. In this library-based study the current situation of bony fish fisheries and biology of these species has been surveyed in Iranian waters of the Caspian Sea . In this survey internal and external environmental factors of bony fishes activities were considered. Using SWOT analysis method, current situation of fisheries was investigated..One of the most important strategies for conserving anadromous species such as Caspian kutum , common carp, roach , bream and …. is rehabilitation of the natural spawning ground in rivers, coastal lagoon specially Anzali lagoon .By conducting this strategy not only restocks of bony fishes is done ,but also reduced the cost of artificial restocking programs and releasing fingerlings .In short term , it is nessesary to enhance the stocks of the species that have low catch is done by huge releasing of the fingerlings and study the qualification of the program. Iranian Fisheries Science Research Institute Published

The project of the Study on fishing and resource management of fisheries within Southern Caspian Sea was conducted on the base of an agreement made between fisheries organization (Shilat) and the Iranian fishery research organization (IFRO) signed in 2010. The study has several phases. The final report of the fishery on fishing and resource management of fisheries within Southern Caspian Sea (Gilan, Mazandaran & Golestan provinces) is consisted of several sections such as: 1- The Survey status of biology and catch of Kilka fishes , Bony fishes and Estrogen fishes and also the status of aquatic resource conservation in the Southern part of Caspian Sea 2- Fishing analysis in the Southern part of Caspian Sea 3- Fisheries development Strategies, policies and plans in the Southern part of Caspian Sea In this survey and library-based study, internal and external environmental factors of shilat activities are considered. Using SWOT analysis method, current situation of fisheries is investigated. In this regard, all fisheries activities were divided into four groups, then, the strengths, weaknesses, opportunities and treats of internal and external environment will be analyzed. A considerable number of tables and matrixes were prepared and policies and strategies as seen of final report were carried out.

The project of the Study on fishing and resource management of fisheries within Southern Caspian Sea was conducted on the base of an agreementmade between fisheries organization (Shilat) and the Iranian fishery research organization (IFRO) signed in 2010. The study has several phases. The final report of the fishery on fishing and resource management of fisheries within Southern Caspian Sea (Gilan, Mazandaran & Golestan provinces) is consisted of several sections such as: 1- The Survey status of biology and catch of Kilka fishes , Bony fishes and Estrogen fishes and also the status of aquatic resource conservation in the Southern part of Caspian Sea 2- Fishing analysis in the Southern part of Caspian Sea 3- Fisheries development Strategies, policies and plans in the Southern part of Caspian Sea In this survey and library-based study, internal and external environmental factors of shilat activities are considered. Using SWOT analysis method, current situation of fisheries is investigated. In this regard, all fisheries activities were divided into four groups, then, the strengths, weaknesses, opportunities and treats of internal and external environment will be analyzed. A considerable number of tables and matrixes were prepared and policies and strategies as seen of final report were carried out. Iranian Fisheries Science Research Institute Published

Recently, the ecology of the Caspian Sea coastal has undergone with increasing development of human activities and industrial wastewater discharge. Therefore, considering the current situation, evaluate of pollutants issue in the Caspian Sea is very important. Results of this study showed that levels of heavy metals (Cd, Cr, Cu, Fe, Pb, and Zn) of water had lower than standard and also acceptable for aquatic life. Significant accumulation of metals such as Co, Cu and Cr in the sediment was observed at transect Sefidrood and Anzali in comparison with six other transects (Turkmen, Amirabad, Babolsar, Noshar, Tonekabon and Astara) and for Ni at transects Sefidrood and Astara compared with six other transects (Turkmen, Amirabad, Babolsar, Noshahr, Tonekabon and Anzali) (P

The intensive culture of common carp (Cyprinus carpio) evaluated in fiberglass tanks(2*2m) with feeding on pellet during 8 weeks.The fish (n=201)of common carp selected from three treatments along with three replicates as the average of fish weight was less than 100(g )which divided into 0.05).The common pellet food was chosen for feeding from market as fish were fed by the mean of 4% of their body weight a day. The result indicated that the mean of particular growth ratio at first treatment (0.54) has higher than second treatment (0.34) but in comparison with third treatment (0.46), there was no statistically significant difference (P

During the past decades the environmental status of the Caspian Sea has changed. Therefore, study on the biological structure such as: age, growth, Lm50%, feeding of fishes is necessary. In the present study the biological characteristics of some commercial important species including kilka, kutum, golden grey mullet and carp were studied during 2006-2010. Kutum, golden grey mullet and carp predominated in the catch composition of bonyfishes, representing 61.3, 29.6 and 7.6% of the total catch. The average fork lengths of kutum, golden grey mullet and carp were 38.4, 32.7 and 36.7 cm, and weights were 784.5, 411.0 and 977.0 g, respectively. The values of b in length-weight relationships were 3.02 and 2.97 for kutum and golden grey mullet indicating an isometric growth. The value b for carp was 2.89, indicating an allomertic growth. The maximum age of three species was 12 years. Von Bertalanffy growth equations were estimated as: for kutum: for golden grey mullet: and for carp: The sex ratio of three species showed that females were dominant. Spawning migratory of kutum was started in March. The gonadosomatic index value of kutum peaked in March and April. The spawning season of carp expended from March to August. The gonadosomatic index value of golden grey mullet peaked in September and then declined in November and December. Absolute fecundity of kutum, golden grey mullet and carp were 64400, 700800 and 131000 eggs, respectively. Length maturity (Lm50%) of three species were 39.07, 28.4 and 31.6 cm, respectively. The highest feeding intensity (Gastrosomatic index=GSI) for females and males were 313.9 ± 65.9 and 350.7±103.7 in October; and the lowest value of GSI were 19.4 ±59.2 and 144.1±85.04 in March, respectively. There are significant different between GSI with male and female in difference months (P

Annually, many data of hydrology and hydrobiology of the southern Caspian Sea at Iran's coasts were collected by Caspian Sea Research Institute of Ecology. The data which had been collected by researchers submitted annually in several reports but has not been processed all at once. Fluctuations of various parameters were surveyed and the relationships between them were analyzed. The main goal of this research is to analysis the data were obtained from 1994 to 2006 and show changes the concentration of various parameters in the Caspian Sea. Physicochemical data indicated that the average trend of transparency and salinity was decreased from 1994 to 2006 annually, where the salinity value was decreased from 12.37 ppt (part per thousand) to 11.5 ppt. The average of dissolved oxygen was increased from 6.4 to 8.6mg/l. pH has slightly fluctuated from 8.15 to 8.31. However, with increasing depth from surface to bottom, the average of dissolved oxygen was sharply decreased (DO concentration in surface and 800 m was 7.18 and 1.45 mg/l, respectively). The trend of salinity and pH fluctuation was very slow with depth but the salinity has an increasing with incrementing of depth but pH has a decreased trend. The average of organic and inorganic phosphorus and TP was nearly increased. The average of Nitrate and Silica sharply increased comparing to depth but the average of Nitrite and organic Nitrogen decreased. The results showed that the temperature fluctuation in different water layers was low in winter but the dramatic decreasing of temperature was occurred at 10-20 m (in spring), 20-50 m (in winter) and 50-100 m (in autumn). With increasing of depth (Slope of the Sea), transparency and salinity values have an increasing while DO and pH showed decreased. As a whole, 335 species of phytoplankton were identified, there are 70 species in advance as these species were not seen in this period but 96 of novel's species have been recorded. The lowest and the most of phytoplankton biomass was recorded in 2006 and 2001 while the biomass was 59 and 1034 mg/m3, respectively. Albet, the lowest biomass was recorded at the depth of 100 m (24.1 mg/m3) but the maximum was observed in surface layer (1344.1 mg/m3). The average of phytoplankton biomass was increased after arrival of the ctenophore. There was a significant difference between the average of biomass in different seasons before and after of the ctenophore invasion (P0.137, P>0.782). Before the presence of ctenophore, the worms had been constituted a dominate group with a approximately %45 of total abundance and also %20 of their biomass. After this period, their frequency was sharply increased (more than %85) but the maximum value pertains to Cardidae (more than %90). The species diversity, evenness and richness were varied between .69-2.51, 0.23-0.63 and .011-3.79, respectively. AMBI software, Shanon-Viner parameter was moderate in all seasons from 1994 to 1996 but this parameter was reduced in a bad limit (boundary) in the most seasons from 2002 to 2005. The main parameter of M-AMBI consists of several parameters and also approximately showed similar changes such as Shanon -viner parameter. On basis of this parameter, the ecological quality condition of Caspian Sea was superior limit in all seasons from 1994 to 1996 but after the following years were decreased from good to moderate limits (After the presence of ctenophore). Relationship between abiotic variants and phytoplankton indicated that there was a direct relationship between transparency and salinity while there was a powerful and reversal significant relationship between transparency water temperature, transparency in organic Nitrate, phytoplankton number and transparency phytoplankton biomass. The comparison between different variants average in two periods (before and after the ctenophore invasion) indicated that the average of Kilka catch was decreased, the relative frequency of clupeonella engrauliformis and clupenoella grimmi was sharply reduced but the relative frequency of Clupeonella cultriventris was sharply increased, the species diversity, evenness and richness and the number of zooplankton species were sharply decreased, the average of biomass and transparency was sharply reduced, the average of dissolved oxygen and liza saliens or liza auratus catch were increased. These difference were often significant (P

During the past decades the environmental status of the Caspian Sea has changed. Therefore, study on the biological structure such as: age, growth, Lm50%, feeding of fishes is necessary. In the present study the biological characteristics of some commercial important species including kilka, kutum, golden grey mullet and carp were studied during 2006-2010. Kutum, golden grey mullet and carp predominated in the catch composition of bonyfishes, representing 61.3, 29.6 and 7.6% of the total catch. The average fork lengths of kutum, golden grey mullet and carp were 38.4, 32.7 and 36.7 cm, and weights were 784.5, 411.0 and 977.0 g, respectively. The values of b in length-weight relationships were 3.02 and 2.97 for kutum and golden grey mullet indicating an isometric growth. The value b for carp was 2.89, indicating an allomertic growth. The maximum age of three species was 12 years. Von Bertalanffy growth equations were estimated as: for kutum: for golden grey mullet: and for carp: The sex ratio of three species showed that females were dominant. Spawning migratory of kutum was started in March. The gonadosomatic index value of kutum peaked in March and April. The spawning season of carp expended from March to August. The gonadosomatic index value of golden grey mullet peaked in September and then declined in November and December. Absolute fecundity of kutum, golden grey mullet and carp were 64400, 700800 and 131000 eggs, respectively. Length maturity (Lm50%) of three species were 39.07, 28.4 and 31.6 cm, respectively. The highest feeding intensity (Gastrosomatic index=GSI) for females and males were 313.9 ± 65.9 and 350.7±103.7 in October; and the lowest value of GSI were 19.4 ±59.2 and 144.1±85.04 in March, respectively. There are significant different between GSI with male and female in difference months (P

Recently, the ecology of the Caspian Sea coastal has undergone with increasing development of human activities and industrial wastewater discharge. Therefore, considering the current situation, evaluate of pollutants issue in the Caspian Sea is very important. Results of this study showed that levels of heavy metals (Cd, Cr, Cu, Fe, Pb, and Zn) of water had lower than standard and also acceptable for aquatic life. Significant accumulation of metals such as Co, Cu and Cr in the sediment was observed at transect Sefidrood and Anzali in comparison with six other transects (Turkmen, Amirabad, Babolsar, Noshar, Tonekabon and Astara) and for Ni at transects Sefidrood and Astara compared with six other transects (Turkmen, Amirabad, Babolsar, Noshahr, Tonekabon and Anzali) (P

In the years 2007-2007, 2008-2009 and 2009-2010 the exploitation of bony fishes resources (by 131 beach seines) started on 12 October but finished on 9 April, 9 April and 13 April, respectively. During these periods the total catch of bony fishes were 23537.8, 20045.5 and 18664.8 tonnes, respevtively. During these periods, kutum predominated and represented the highest proportion of total catch at 73.1, 74.0 and 66.9% , followed by golden grey mullet at 18.3, 13.9 and 18.7%, respectively. K values calculated 0.22, 0.15 and 0.14 year-1 and L∞ were 66.0, 62.7 and 70.0 cm for kuttum, golden grey mullet and common carp, respectively. The instantaneous coefficient natural mortality were estimated as 0.386 and 0.35 year-1 for kutum and golden grey mullet, respectively. During three periods, the exploitation rates were 0.789, 0.584 and 0.614 for kutum and 0.71, 0.75 and 0.61 for golden grey mullet, respectively. In the years 2007-2007, 2008-2009 and 2009-2010, the total biomass, from the biomass-based cohort analysis were 56600, 62090 and 61590 tonnes for kutum and and MSY estimated about 24733.7 and 8550.4 tones for kuttum and 11040, 11900 and 14460 tonnes for golden grey mullet, respectively. The ABC (acceptable biological catch) were estimated as 8000 and 2200 tonnes. Iranian Fisheries Science Research Institute Published

In the years 2007-2007, 2008-2009 and 2009-2010 the exploitation of bony fishes resources (by 131 beach seines) started on 12 October but finished on 9 April, 9 April and 13 April, respectively. During these periods the total catch of bony fishes were 23537.8, 20045.5 and 18664.8 tonnes, respevtively. During these periods, kutum predominated and represented the highest proportion of total catch at 73.1, 74.0 and 66.9% , followed by golden grey mullet at 18.3, 13.9 and 18.7%, respectively. K values calculated 0.22, 0.15 and 0.14 year-1 and L∞ were 66.0, 62.7 and 70.0 cm for kuttum, golden grey mullet and common carp, respectively. The instantaneous coefficient natural mortality were estimated as 0.386 and 0.35 year-1 for kutum and golden grey mullet, respectively. During three periods, the exploitation rates were 0.789, 0.584 and 0.614 for kutum and 0.71, 0.75 and 0.61 for golden grey mullet, respectively. In the years 2007-2007, 2008-2009 and 2009-2010, the total biomass, from the biomass-based cohort analysis were 56600, 62090 and 61590 tonnes for kutum and and MSY estimated about 24733.7 and 8550.4 tones for kuttum and 11040, 11900 and 14460 tonnes for golden grey mullet, respectively. The ABC (acceptable biological catch) were estimated as 8000 and 2200 tonnes.

The intensive culture of common carp (Cyprinus carpio) evaluated in fibreglass tanks (2*2m) with feeding on pellet during 8 weeks. The fish (n=201)of common carp selected from three treatments along with three replicates as the average of fish weight was less than 100(g )which divided into 0.05).The common pellet food was chosen for feeding from market as fish were fed by the mean of 4% of their body weight a day. The result indicated that the mean of particular growth ratio at first treatment (0.54) has higher than second treatment (0.34) but in comparison with third treatment (0.46), there was no statistically significant difference (P