Stock assessment of the bony fishes of Golestan province

Total catches of bony fishes in the coastal of south Caspian Sea have been ended to 1554 ton in 1382. The catch of common carp Cyprinus carpio as a one of important commercial species has been lower than others species such as mahisephid, kolmeie and kafal. From commercial catch point of view, the catch of kolmeie is not very important, so that its catch was included only 2% of total bony fish catch in three provinces which are located in south of Caspian sea . In spite of lower common carp catch, in comparison with total bony fish catch in Golestan province more thanb70% catch was belong to Common carp. The higher catch kolmeie among three provinces was related to Guilan with 46% of total catches. Seasonal changes of common carp catch showed maximum and minimum catch were in April 83 and December 82 respectively. The most of (CPUE) was in April 83 and September, October 82. The trend of kolmeie catch showed low fluctuation. Three age groups were specified in kolmeie age composition high and low percent observed in 2 and 3 age groups respectively. Result of biometric information common carp showed most of catch was under standard fisheries catch

The first report of shrimp Macrobrachium nipponense in Alagol, Almagol and Ajigol Lagoons, Golesta Province

For the first time, Oriental river prawn Mcrobrachium nipponense were investigated in three international lagoons the (Aalgol, Ajigol and Almagol) in 209-210; sampling take place monthly using collapsible traps (Funnel Trap). In this study the max 2310 male and 1779 female specimens and min 599 male and 667 female specimens were caught, and, 667 in the Alagol and Ajigol respectively. In the three lagoons, females were smaller than males. Comparing the average mean length males and females showed significant difference among the Ajigol with the other lagoons and the Alagol with the other lagoons respectively

The stock assessment of bony fish, carp (Cyprinus carpio) and roach (Rutilus rutilus) in southern coast of the Caspian Sea

In this study, the combination of length, growth rate, mortality rate and also the current of status Operation Carp and roach commercially as important species in southern waters were reviewed. Samples were taken from beach sine net catch and fish were offered at fish market. The age composition of carp and roach was 1 to 16 and 1 to 4 years respectively, most catch carp and roach was in length range of 31 to 39 cm and 18 to 20 cm respectively. Growth parameters during the program by ELFFAN I FiSAT for Carp and Roach obtained from von Bertalanffy growth function were L_∞ =70.78 and 32.39 cm, K = 1.24/year and 1.24/year; respectively. the growth parameters such as infinite length( L_∞), growth coefficient (K) and t0 age zero base on One Brtalnfy equation estimated, 78.70, 0.14, 32.39, 0.5 ,-0.5 Total mortality coefficient Using the method of catch curve (Z), natural mortality rate using the empirical formula Pauli( M), fishing mortality (F) using the formula = Z - M and Growth performance index (Ǿ) for Carp and Roach were obtained 1.5year^-1, 0.9year^-1, 0.5year^-1, 0.26year^-1, 1.24, 0.4, 2.85 and 2.54 respectively. The biomass (B) and Maximum Sustainable Yield (MSY) with the present effort for Carp and Roach were estimated 1628.7t, 368.9t and88.06t, and 32.7t respectively

Identification of distribution of Macrobrachium nipponense in freshwater ecosystems and coastal waters of Golestan Province, Caspian Sea

Distribution of freshwater shrimp (Macrobrachium nipponense) in the freshwater ecosystems such as Alagol, Almagol, Ajigol lagoons, Gomishan lagoon and Gorganrud River. Sampling were done from may 2009 to my 2010 parameters such as, length frequency, growth rate, sampling, feeding, environmental factors and sedimentation were investigated. 3689 females and 8551 males were collected and biometrical parameters were recorded. Total length ranged between 3.2 to 98.7 mm. The parameters b of length-weight relationship in Alagol, Almagol, Ajigol were 3.49, 3.15, 3.45, 3.22 and 3.22, 3.28 for male and female, respectively. It shows in all lagoons for male and female growth is positive Allometric. Spawning period was from May to June. The length first at maturity (total and/or carapace) for three lagoons was 50.5 mm and 133 mm, respectively. The minimum and maximum of egg volume were 0.12 mm3 in Ajigol and 0.07 mm3 Alagol, respectively. The relationship between fecundity and length was found to be linear regression models for Alagol, Ajigol and nonlinear regression models for Almagol lagoon. Result showed that this species is omnivorous. The minimum and maximum temperature was 6.5ْ C in fall and 33ْ C in summer. The lowest and highest fluctuations of pH level in Ajigol and alagol lagoons were 8.2-9.2 and 7.2-9.8. Among three lagoons, the most EC was 5.9 Ms/c in Alagol lagoon. The Gorganrud River shows the maximum EC, 16.7 Ms/c