Changes in stocks of anchovy kilka, Clupeonella engrauliformis in Iranian coastal zone of the Caspian Sea (1995-2011)

The main objective of the present study was qualitative and quantitative assessment of anchovy stock, Clupeonella engrauliformis in Iranian waters of the Caspian Sea during (1995- 2011). Over this period, total catch of anchovy kilka increased from 32000 tonnes in 2005 to 67000 tonnes in 1999 and decreased sharply to 80 tonnes in 2011. In the years 1995-1999, catch per unit effort (CPUE) was fairly constant (2.92-3.52 tonnes/(Vessels×Nights) which fell to 0.01 tonnes/(Vessels×Nights) in 2011. Total biomass and spawning stock biomass (SSB) had the same trend as CPUE. During 1995-1999, total biomass of anchovy kilka ranged between 158500-185900 tonnes which dropped to 2000 tonnes in 2007. The SSB showed a downwardtrend from 105500 tonnes in 1997 to 1950 tonnes in 2007. In age compositions of the catch, age 3+ was the largest age group. From 2001 to 2003, age 2+ predominated. Finally, number of young specimens declined and age 6+ and 7+ groups were predominated in the last years. Present study indicated that the situation of the anchovy kilka is critical. A coordinated international effort is needed to provide implementation of sustainable management and responsible fishing activities in the whole Caspian Sea

Determination of technical regulation & criteria of Iranian fisheries & marine aquatics

Accurate scientific and practical plan for achieving the goals of the Islamic Republic of Iran within the framework of Vision development 1404, is the infrastructure achieving sustainable development of the country. Order to achieve the above mentioned objectives and in order to the comprehensive development plans in the country, Iranian fisheries research organization adjust the fifth developing plan for support of executive related departments in country with mobilization a large number researchers consists of several working groups of IFRO affiliated research centers. The fifth developing plan consist of three chapters for report of the forth developing plan and intrudction of research , construction plans and financial support (budjet) for period of 2011-2014 A.C

Determination of biomass of fishes in Shadegan Wetland

Biomass estimation of fishes were done by depletion method in Shadegan Wetland in 2011-12. Fishing effort and landing catch amount per unit effort was done via random oversea in fixed landing area monthly. Fishermen and catch statistics were obtained from census. Total catch was calculated from multiplication of effort and average catch. Fishes biological characteristics survey indicated that Golden barb (Barbus luteus) and Berzem (Barbus pectoralis) has maximum (62 kg/ha) and minimum (4 kg/ha) biomass respectively. Maximum and Minimum biomass was in spring (380 kg/ha) and in winter (58 kg/ha) respectively and mean biomass was estimated 249 kg/ha in whole area during one year. Number of fishermen were about 1317 and maximum fishing effort was in April, May and June. Total fish landing was 4300 tons per year in which 1119 tons was calculated in April. Large scaled barb (Barbus grypus) and Abu mullet (liza abu) had maximum and minimum mean length and weight. The range length of most of fishes was low and their spawning season was in winter and spring. Length- weight relationship indicates their isometric growth. Despite of 45% decrease of number of fisherman to previous time (2008), catch effort and exploitation was increased (20%). Regarding fish living area (70000 ha), total biomass was 17430 tons

Stock assessment of banana shrimp (Penaeus merguiensis) in coastal waters of Hormozgan Province

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

Study forming of growth rings in the Caspian bony fishes (Step 1: Common carp Cyprinus carpio Linnaeus, 1758)

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

Age, growth, feeding regime reproduction and sexual maturity of Rutilus frisii Kutum in Iranian coastal waters of Caspian Sea

The project of Age, growth, feeding regime and fecundity of Kutum (Rutilus frisii Kutum) survey started in south of the Caspian Sea from 2006 to 2007. The aim of project was related to determination of length maturity (Lm50%), identification of feeding animals, and investigation some of biological aspects uncluded in sex ratio, growth and age structure in southern of the Caspian Sea. Total 2706 specimens of Kutum were surveyed. The age structure of Kutum has nine age groups that included in 1, 2, 3, 4, 5, 6, 7, 8, and 9 years. The result showed that maximum frequency was about 39.3 % and were belong to 4 years and minimum frequency which was about o.1 % were belong to 9 years. The maximum and minimum fork length and weight were 58 and 21cm with mean (±SD) 38.4 (± 6.4) cm; 2450 and 104g with mean (±SD) 784.2 (± 383.30) g , respectively. There are significant different between fork length and weight in male and female of Kutum at difference months (ANOVA, P<0.05). The sex ratio of males to female was 0.65: 1 (males: females). The least and high condition factor was 1.5 in January and 2.17 in October, respectively. Length maturity (Lm50%) was 39.07cm. Minimum and maximum absolute fecundity was varied from 15713 to 130737 eggs with mean (±SD) 69961.7 (± 3836.4). Significant different was between absolute fecundity with fork length and weight (p<0.05). Gonadosomatic index (GSI) mean for females were 2.5±0.2 (autumn) and 17± 0.2 (spring); 1.2± 0.1 (autumn) and 4.1± 0.2 (spring) for males, respectively wich coincided to spawning period. The highest feeding intensity (Gastrosomatic index) for females was 313.9 ± 65.9 in October and 119.4 ±59.2 in March; 350.7 ±103.7 in October and 144.1±85.04 in March for males, respectively. There are significant different between GSI with male anfemale in difference months (ANOVA, p<0.05). The Bertalanffy growth equation for all populations of Kutum was L (t) = 63.92[1-e ^0.19 (t (-1.00)]. Main prey mature of Kutum was Cerastoderma lamarki; Gastropoda and Balanus were subordinate, and Crab, Hypanis, Fish (Neogobous sp.) Algae, egg, and scale were random preys. Planktone groups comprise to Exuviaella, Nitzchia, Osillatoria, Synedra, Nematoda, Navicolla, Diatoma, Rholcosphenia were preys juvenile of Kutum. Based on ISI (Important species index), Cerastoderma lamarki and Balanus were dominant species in feeding of Kutum. As a result, growth, fecundity and length maturity of Kutum declined which may due to loss natural breeding area, overfishing (overlapping between fishing and spawning period) and artificial breeding that commenced since 1982. Hopefully, this information can be used in fisheries management

The Study of biology (age, feeding and, reproduction of Rutilus rutilus caspicus in south coast of the Caspian Sea (Iranian waters)

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

Study on the growth status of mullets with viral nervous necrosis disease in the southern Caspian Sea

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

Growth performance and age composition of Salmo trutta caspius in Iranian part of Caspian Sea

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

Stock enhancement and estimation of growth rate of green tiger prawn (Penaeus semisulcatus) and banana shrimp (Fenneropenaeus merguiensis) released in the Persian Gulf

Present study was conducted in the Persian Gulf (Iranian waters) from 2009 to 2012. The main objective of the research was economical evalution of the stock enhancement of banana prawn (Fenneropenaeus merguiensis) and green tiger shrimp (Penaeus semisulcatus) in the studied area. Also tagging effects on the growth and mortality of tagged shrimp were studied. In banana prawn, broodstock shrimps were hatched in June. In July 2010 and 2011some of the juvenile of this species were marked by red fluorescent liquid injection and released were made at night in the estuaries of Tiab, Kolahi and Koolgan in the Hormozgan province. 84000 juveniles of banana prawn in 2010 and about 50000 in 2011 were released in this area. In Bushehr province waters, adults shrimp were reared and when juveniles reached to optimum size, some of them were tagged by red and blue coloures and were released in the coastal waters of Bandargah and Delvar. Tagging and releasing program of green tiger prawn was performed in 2010 and 2012. A total number of 8000 prawn in 2010 and about 30000 juveniles prawn in 2010 were released. Activities for recaptured shrimps were informed by posters describing the tagging program that were distributed to local peoples, as well as local magazines, and a tagging program awareness film was broadcast on national television three times prior to the shrimp fishing season and during catch season. To encourage people to report recaptures a reward of two handered thousent riales was paid for the return of each marked shrimp accompanied by information. Economical evaluation of banana prawn was performed based on releasing and recaptured program in 2011. As it mentioned in this year 50000 of juvenile shrimp were tagged and released. At the same time 4700000 of unmarked shrimp were released in this area. In the shrimp season 11 (./022%) of tagged shrimp were recaptured. Movements of tagged shrimp were northwesterly to released area. Weight average of tagged prawns was 1.2 gram. Mean weight of the recaptured prawns was 22.06±4.9 gram. Body weight Growth of the recaptured prawns was between 16-26 grams with the growth speed of 0.88-1.41 per week. The number of recaptured prawn to the released prawn was 0.022 percent. Based on the released prawns (4700000) to the recaptured percent (./022%), about 103400 of released shrimp with mean weight of 2.5 tones were observed in the Hormozgan shrimp catch. The average price of shrimp in the studied year in the local market was 85000 Rials per kilogram. These results showed that the ratio of profit is 210 milion riales. In the taggiing program of green tiger prawn in the Bushehr waters only one recaptured shrimp was observed in the catch season (2012). Total weigth and total length of this prawn was 99 gram and 22 centimeter respectively .given the small percentage of the recaptured, economical analyses was not performed on this species. The effects of tagging on the growth and mortality of green tiger prawn were studied. The present study was carried out in the shrimp research station in Bandargah and Abzistan shrimp Hatchery Company in Delvar during 2010 and 2012. The accuracy of the study was more rialable in 2012. In this year growth and mortality of juveniles that was marked by red and blue coloures, were studied in both area Bandargah and Delvar. In Bandargah, three tanks of 300 l each with 30 specimens were used for untagged shrimp as a control group, and tagged with injected liquid fluorescent during 98 days. Length and weigh of 10 specimens were measured evenly in different times. ANOVA results (α = 0.1 and α = 0.5) showed no significant differences between length growth of tagged shrimp and control group. The mortality of two groups was evaluated by numbering of remained shrimps and the average of survival was 52 percent in the tagged and 44.5 percent in tagged shrimps. In the Delvar station, Abzistan Company, the specimens were kept in the 9 tanks each 300 l that included of 30 untagged shrimps, 30 blue tagged shrimps and 30 red florescent tagged shrimp. The growth and mortality of this station were evaluated during 110 days. The growth rate of the specimens were measured and recorded evenly. The results of ANOVA (α = 0.1 and α = 0.5) showed no difference significantly in the weight growth of tagged and control groups. The mortality rates among the control group, red tagged and blue tagged were 63 percent, 59 percent and 40 percent. The mortality of the groups was differences in the two stations and it seems the management and environmental conditions were more affected on the mortalities. The results of the study show that the ratio of profit to the coast is 0.46 that is covering half of the coasts, so that the expenditures are two times more than profit. This result is the minimum of economical value of stock enhancement of shrimp. The results of study showed that the injected tags into the body tissue of shrimp has no affected on the growth rate and mortality