A comparative analysis of feeding habits of sturgeon fish in shallow coastal waters of Mazandaran and Golestan Provinces, south Caspian Sea

Feeding habits of different genera of 354 sturgeon specimens (Acipenser persicus, Acipenser nudiventris, Acipenser stellatus) were compared over the years 1999-2000 caught in the coastal waters less than 20 meters deep of Mazandaran and Golestan provinces, southern Caspian Sea. The caught specimens ranged 30-18cm in length. Overall, 16 families of food items were identified in the digestive system of the sturgeon specimens, of which 11 belonged to macro-benthos. The sturgeon fishes preyed on food items composed of Annelids 50.8%, Amphipoda 41.5%, small fish 4.8%, Decapoda 2% and Bivalvia 0.9%. Fish specimens shorter than 40 cm were mostly found feeding on shrimps, polychaets and gamarids. The 41-80cm length class mostly fed on shrimps, gamarids, polychaets, bivalves and smaller fish. Sturgeons longer than 80cm fed mostly on shrimps and smaller fish. Average fat coefficient for Acipenser stellatus was 0.43. A. persicus showed a fat coefficient 0.63 while that of the A. nudiventris was 0.97. Average stomach fullness was 8.3, for Acipenser stellatus, 100 for A. nudiventris and 165 for A. persicus. We found a similar diet between group one fish less than 40 cm long and group two with fish in the length class 41 to 80cm (r=0.7)

Seismic pounding mitigation by using viscous and viscoelastic dampers

This paper examines the effects of viscous and viscoelastic dampers as an efficient technique for seismic pounding mitigation. To aim that, 15 steel frame models with different numbers of stories and bays and also with different types of ductility were analyzed under 10 different earthquake records for assigned values of link damping and stiffness and the most suitable values of damper parameters (damping and stiffness) are presented. Moreover, it is demonstrated that viscous dampers can perform as efficiently as viscoelastic alternative with a more economical aspect for pounding mitigation purposes.Keywords: Adjacent buildings;Viscous and Viscoelastic links;Separation distance;Poundingmitigatio

The investigation and morphological study of two type of Crass carp: Ctenopharyngodon idella and survival rate of their larvae

The two groups of grass carp, have been propagated in North and South fish farms and then the larvae were transferring to Abziroshd and culture fish farm of Mazandaran. The fingerling at eight weight classes of 2 to 500 gram were investigated morphologically and some morphometric and meristic were compared. The South grass carp was significant difference (P<0.05) with the North, in case of weight with the same length, number of vertebral and gill raker. The coefficient of variance (CV) of meristic characters of South Grass carp was in the range of 1.2 to 9.8 while in Mazandaran grass carp 2.8 to 8.6. This CV illustrate the low variance in both population. This research study showed that the two stocks can be regard as difference races from one ancestor

Genetic characterization of Vimba vimba persa in southern part of the Caspian Sea using microsatellite marker

Population genetic structure of Vimba vimba persa was investigated using microsatellite markers from 4 regions along the Iranian coastline of Southern the Caspian Sea (Anzali lagoon & havigh River in Gilan province, BabolRoud River in Maz&eran province & GorganRoud River in Golestan province). Genomic DNA from 121 specimens was extracted from fin tissue by phenol-Chlorophorm method & PCR reaction was accomplished with 17 microsatellite primers, out of 17 microsatellite primers 14 loci were amplified, in which 10 of them were amplified with reasonable polymorphism & 4 were monomorphism. Totally 302 alleles were identified on average 7.5 Observed & expected heterozygosity averages were 0.80 & 0.77 respectively. Most cases significantly deviated from Hardy-Weinberg equilibrium (p 0.01). The estimation of Fst (p 0.01) revealed significant population structuring & estimate four population of Vimba vimba persa is identified in the Caspian Sea. These studies were to apply & develop population genetic approaches to assist conservation, sustainable harvest & restocking of these populations

Survey on environmental pollutants (heavy metals, hydrocarbons, surfactant and chlorinated pesticides) in southern part of the Caspian Sea

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<0.05). The amount of Zn in fish muscle Liza saliens was maximum and then metals such as Fe, Cu, Pb, Cd, Ni, Hg and Co were recorded (P<0.05). In the north of Iran, two kind of bony fish, such as R..frisii kutum and Liza.s have maximum catchments as compared with other bony fish in the Caspian Sea. Based on calculation of risk of Target Hazard Quotient (THQ), we obtained THQ was less than one for all metals in young and adults human. Thus, consumption of R..frisii kutum and Liza.s per capita with 6 kg will not be at the risk for young and adults. Among of oil derivatives, polyaromatic hydrocarbon (PAHs) is hazardous compounds in the environment. Environmental Protection Agency (EPA) was announced 16 compositions of PAHs as an index. The results of this project showed that concentration of two and three rings of PAHs was lower than 4, 5 and 6 rings of water, sediment and fish at most stations and seasons. Among of 16 PAHs, only Benz(α)anthracene, chrysene, Benzo(α)pyrene and Dibenz (α, h)anthracene compounds were contained with ecological risks (HQ) more than one in the water and sediment. In addition, three compounds such as Chrysene, Benz(α)anthracene and Benzo(α)pyrene were observed in the edible fish tissues (Liza.s and R..frisii kutum) which have high ecological risks in the water and sediment. During four seasons (spring, summer, fall and winter), maximum concentration of organochlorine residue in the surface water (5m depth) were belong to β-Endosulfan (Turkmen), Dieldrin (Babolsar, Tonekabon) and endosulfan sulfate (Astara) and at 10m depth were γ-BHC, Dieldrin compounds (Tonekabon), DDT (Turkmen) and Aldrin (Babolsar). This values at 50m depth were belong to γ-BHC (Anzali), δ-BHC (Tonekabon), Dieldrin (Amirabad), and heptachlor (Amirabad). Maximum percentage of organochlorine pesticides residue in the sediments was belonging to only Aldrin compound at stations Turkmen, Babolsar and Tonekabon. In addition, maximum concentration organochlorine pesticides residue in fish tissue (Liza.s and R..frisii kutum) was DDT and Endrin aldehyde compounds. Mean surfactant concentration (LAS) of surface water (5, 10 and 50 m depths) at eight transects was 0.017±0.049 mg/l. The maximum concentration of LAS were 0.084 mg/l and 0.082 mg/l in spring and summer (Anzali transect), respectively. This value was 0.035 mg/l and 0.060 mg/l in autumn and winter (Sefidrood transect), respectively. As a conclusion, the concentration of surfactant in the Caspian Sea basin is not critical as compared with standard level

Stock assessment of kutum (Rutilus frisii kutum) in the Iranian waters of Caspian Sea

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 Caspian Sea from 2013 to 2015. The catch of Kutum was 6112.8 and 5599.2 tons and CPUE were 181.1 and 183.5 kg/haul in 2013-2014 and 2014-2015, respectively. The mean (± SD) of fork length were observed 39.4±6.1 and 40.7±5.6 cm and for total weight were 805.1±378.0 and 891.5±384.6 gram in 2013-2014 and 2014-2015, respectively. The most predominated of length class was obtained 40-42 cm and frequency of immature individuals were observed 37.8 and 44.4 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 4 to 6 years comprised up to 84 percent. In length – weight relationship a, b and r2 were calculated 0.011, 3.02 and 0.96 respectively. K value, L_∞ and t0 were calculated 0.19 (/year), 61.3 cm and -0.99 respectively. Mortality parameters such as Z, M and F were calculated 0.82, 0.36 and 0.46 respectively and Exploitation rate were calculated 0.56. The biomass of kutum estimated 41000 tons and the acceptable biological catch calculated 8250 to 9750 tons. 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

Identification genetic characterization and population of Barbus brachycephalic caspius, Lucioperca lucioperca, Rutilus rutilus caspius, Rutilus frisii kutum and Salmo trutta caspius in southern part of the Caspian Sea by molecular method (Microsatellites) and formation DNA bank

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<0.05). The genetic diversity was significantly different between samples of Golestan and Gilan, Golestan and sefidrood, Golestan and Tajan, Mazandaran and sefidrood and Gilan and Tajan (p<0.05). -Rutilus rutilus caspius: Sevan variable microsatellite loci were used to investigate genetic diversity and population structure of R. rutilus caspius. The mean of effective and observed alleles were 5.75±0.30 and 4.76±0.25 respectively. Also, the mean of expected and observed heterozygosity were 0.58±0.18 and 0.73±0.01 respectively. All of the samples (except golestan samples in LOC3) possible tests were found to deviate significantly from the Hardy–Weinberg equilibrium (P<0.05) Of the analysed loci, the genetic divergence was significantly different between samples of Golestan and Gilan, Gilan and Mazandaran and Gilan with Gorgan bay (p<0.05). -Salmo trutta caspius: Genetic characterization of S. trutta caspius was comparatively analyzed with mitochondrial DNA sequencing that 45 haplotypes was observed. The average of expected and observed heterozygosity were 0.61±0.35 and 0.33±0.12 respectively. The maximum of haplotype diversity (0.089±0.04) was in sardabrood river and the minimum was in Astara river (0.81±0.02). Also, the maximum of nucleotid diversity was 0.13±0.07 in Sardabrood and Chalos rivers and the minimum was 0.11±0.06 in Tonekabon river. In addition, the maximum and minimum of FST was 0.08 and 0.01 respectively. Of the analysed loci, the genetic divergence was significantly different between samples of Astara and Chalos, Astara and Tonekabon, Chalos and Karganrood and Tonekabon with Kaganrood (p<0.05). - Barbus brachycephalus caspius: The size of amplified fragment was 800 bp in all of the samples. There were 24 variable loci and 12 haplotype that the maximum of haplotype was in Gilan area (8 haplotype). The average of expected and observed heterozygosity were 0.003±0.35 and 0.42±0.12 respectively. The results showed that the haplotype diversity was significantly different between samples of Sefidrood whit other samples (p<0.05). In addition The maximum of nocleotid diversity was 0.005±0.003 in Sefidrood and minimum was 0.001± 0.001 in Tajan river. Of the analysed loci, the genetic divergence was significantly different between samples of Gilan and Tajan, Mazandaran and Sefidrood (p<0.05). -Lucioperca lucioperca: The genetic diversity of L. lucioperca was analyzed by using microsatellite markers. Seven primer sequences available for were tested to amplify microsatellite loci that all of loci were polymorphic. The mean of effective and observed alleles were 6.14±0.45 and 3.88±0.34 respectively. Also, the mean of expected and observed heterozygosity were 0.662±0.03 and 0.70±0.02 respectively. The most of samples in PflaL6, PflaL7and PflaL8 loci possible tests were found to deviate significantly from the Hardy–Weinberg equilibrium (P<0.05). The maximum of FST was 0.30 between Gilan and Mazandaran samples that there were minimum gene flow (8.18). The genetic divergence was significantly different between samples of Gilan and Mazandaran and Golestan whit mazandaran (p<0.05)

Determination of pollution condition in Babolroud River from viewpoint of pesticides and agrochemicals fertilizers

Babolroud River is one of the important rivers for fisheries and environmental aspect that locared in center part of Mazandaran province. The river has a span of 92 km starting from Albourz mountainous and end up at the southern part of Caspian Sea. This study was done for five months (3rd Feb. through 5th July, 2008) for the better understanding of pollution situation such as organophosphorous, organochlorine pesticides and agrochemical fertilizer that drainage from paddy fields and horticultures to the river. A total of three main sites for pesticides and plus five sub-sites for drainage were selected for observation in three different regions of the river (mountainous, plain and estuary). The organochlorine and organophosphorous pesticides measured by GC (ECD and TSD detectors) with US-EPA (508) and AOAC procedure and agrochemical fertilizer parameters were measured by ASTM method. The maximum concentrations of aldrin, lindane, heptachlor epoxyde, DDE and β- BHC (period 1), δ- BHC and endrin (peiod 2), heptachlor and DDT (period 3), α- BHC (period 3 & 4), dieldrin (period 4) were 6.02, 0.85, 0.51, 0.50, 0.22, 0.35, 0.23, 0.50, 0.46, 0.19 and 0.16 µg/l, respectively. The maximum concentrations of four components of organophosphorous such as Diazinon and Chlorpyrifos (period 1), Malathion (period 2), Azinphos methyl (period 3) were 1.36, 0.46, 0.44 and 2.56 µg/l, respectively. The maximum amounts of tree components of parameters of agrochemichals fertilizers indictor such as total nitrogen (period 2, sub-site 5), total phosphorus and orthophosphate (period 4, sub-site 5) and organo-phosphorus (period 3, sub-site 4) were 5990, 1290, 1220 and 336 µg/l, respectively. The maximum concentrations of organochlorine pesticides components in sediments of the river such as lindane (period 2, site 2), δ- BHC (period 1 site 3), α- endosulfan (period 1, site 2), endrin and heptachlor epoxide (period 2, site 2) and DDE (period 2, site 1) were 0.99 0.54, 0.29, 0.19 and 0.19 µg/l, respectively. The maximum concentrations of organochlorine pesticides components in fish tissue of the river such as endosulfan sulfate, lindane, endrin, δ- BHC and DDE were 0.32, 0.29 0.27, 0.25 and 0.21 µg/l, respectively

A survey of feeding habits of economic benthic feeder fishes in the southern of Caspian Sea (Rutilus frissi kutum, Rutilus rutilus caspicus, Cyprinus carpio, Liza auratus and Liza saliens)

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