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The objective of this study was to assess the impact of a native probiotic product on the intestinal bacteria biodiversity of Penaeus vannamei. Shrimp larvae were administered the probiotic via food (treatment 1), through culture water (treatment 2), and a control group received no probiotics (treatment 3). After three months of rearing, bacteria were isolated from the shrimp intestines, and initial identification was conducted based on morphological, biochemical, and physiological traits. The diversity of intestinal bacterial flora was assessed using PCR-RFLP methods, focusing on the determination of 16S rRNA gene sequences. Results revealed a significantly higher abundance of cultivable bacteria in the intestines of shrimp from treatment 1 (2.4 x 107 CFU/gr) compared to those receiving probiotics through water (6.16 x 106 CFU/gr). The probiotic product led to a reduction in bacterial diversity in the intestines of treated shrimp, decreasing from 10 to 6 genera. Additionally, the frequency of Vibrio bacteria decreased by 20%, while other opportunistic pathogenic bacteria such as Pseudomonas, Aeromonas, Shewanella, and Photobacterium were eliminated. Overall, the findings suggest that administering probiotics through food was more effective in modulating the diversity of the shrimp intestinal microbiome. This study enhances our understanding of the impact of indigenous probiotics on the composition and dynamics of the intestinal microbiome of P. vannamei.

In this study, the effect of dietary supplementation with mineral and Nano forms of two essential elements, iron and copper was investigated on the blood biochemical profile, antioxidant, and immunity performance of Schizothorax Zarudnyi with an average weight of 23.97±0.45 g. The fish were fed with diets containing (1) no copper and iron supplement (basal diet), (2) 150 mg/kg of mineral iron supplement, (3) 3 mg/kg of mineral copper supplement, (4) 150 and 3 mg/kg of iron and mineral copper supplement respectively, (5) 150 mg/kg of iron nanoparticle supplement, (6) 3 mg/kg of copper nanoparticle supplement, and (7) 150 and 3 mg/kg of iron nanoparticles and copper nanoparticle supplement, respectively for 60 days. Dietary addition of iron and copper in both forms improved blood biochemical profile, antioxidant, and immunity performance compared to the control. The addition of Nano form led to significant improvement in blood parameters and antioxidant defense system compared to the mineral-fed treatments. The simultaneous use of the Nano form of these two elements led to a significant improvement in serum total protein, albumin, globulin, HDL, cholesterol, triglyceride, MDA, GPx, SOD, CAT, C3, ACH50, and serum bactericidal activity compared to other treatments. In conclusion, the simultaneous use of iron and copper at the rate of 150 and 3 mg/kg of diet in Nano form is much more effective than their mineral or individual Nano forms to improve the antioxidant and immune parameters of S. Zarudnyi.

This study investigated the effect of different levels of mangrove leaf powder (Avicennia marina) on growth performance and survival of juvenile whiteleg shrimp (Penaeus vannamei). Shrimp with an average weight of 5.26 ± 0.21 g were stocked in 12 tanks of 300 liters with 40 shrimp per tank, and were fed with four different levels of mangrove leaf powder including 0 (control), 2.5, 5 and 10%, during 90 days in three replicates. During the feeding trial, growth indices (body weight gain, total length increase, carapas length and width increase) and survival rate were measured. The results showed an increase in the amounts of growth indices of shrimp fed with different levels of mangrove leaf powder compared to the control treatment (P

This study was carried out to evaluate the effect of dietary mangrove (Avicennia marina) leaf powder on hemolymph immune indices of Pacific white shrimp (Penaeus vanamei) at low water temperature stress. After 90 days of feeding with different levels of mangrove leaf powder (0, 2.5, 5 and 10%), the temperature gradually decreased from 24 to 2-3 °C. After 24 hours, survival rate was measured and three live shrimp were sampled to measure hemolymph parameters. The results showed that total haemocyte count (THC) level was significantly higher in 5% treatment compared to the other treatments (P

Regarding the problems caused by biofoulings in fishing cages, the present study was conducted to investigate the reduction of biofouling accumulation in fishing cages using two antifoulings of Copper oxide (Cu2O) and Tin chloride dehydrate (SnCl2. 2H2O) with four doses of 5, 25, 50 and 75 g per kg of net. Sampling was carried out in Bandar Lengeh, Hormozgan province from March to August 2015.In spring Saccostrea cucullata, Amphibalanus sp., Enteromorpha clathrata and Paracyathus stokesii and in summer Thais mutabilis, Amphibalanus sp., Saccostrea cucullata and Paracyathus stokesii were identified. The results showed that in both seasons, the treatments of Acrylic resin 35% + Copper oxide 75 g per kg of net and Acrylic resin 35% + Tin chloride dehydrate 75 g per kg of net significantly reduced the biomass of most species (p

In this study, the leaf extract activity of two species of mangrove plants, Avicennia marina (Avicenniaceae family) and Rhizophora mucronata (Rhizophoraceae) was compared in biosynthesis of silver nanoparticles (AgNPs). The AgNPs were investigated using spectrophotometry, transmission electron microscopy (TEM), scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). Absorption spectrum in 420 nm confirmed the synthesis of AgNPs. The evaluation of the recorded TEM images from silver nanoparticles showed that the size of nanoparticles synthesized by A. marina was in the range of 0 to 75 nm and the size of nanoparticles synthesized by R. mucronata was in the range of 0 to 80 nm. The results of FE-SEM image analysis showed nanoparticles with a size between 15 to 43 and 10 to 19 nm for A. marina and R.mucronata, respectively. The results of EDS indicated the presence of 51.6% and 73.5% silver in nanoparticles synthesized by A. marina and R. mucronata, respectively. Results suggest that the leaf extracts of both mangrove species are able to reduce the Ag+ into Ag0 in the solution of AgNO3 at room temperature and synthesize silver nanoparticles of very suitable nanometric dimensions.

The genus Encrasicholina includes economically and ecologically important pelagic small sized anchovies. These fish are endemic to Indo-Pacific waters and are also found in the Persian Gulf. Due to harmful human activities in different forms, the ecosystem of Persian Gulf has suffered great damages in recent decades and its biodiversity is threatened. Therefore, its sustainable development and the preservation of its biodiversity is essential. The first step to achieve this goal is to identify the accurate species biodiversity. DNA barcoding method based on mitochondrial DNA is widely applied to identify the phylogenetic relationships between the species. In this study, we examined the utility of mitochondrial cytochrome oxidase subunit I (COI) for identification of Encrasicholina genus in the Persian Gulf. Sequences sent to the “Barcod of Life Data systems” and NCBI confirmed the morphological identification results. In fact, the larvae that their morphological characteristics were insufficient to identify, were validly identified with COI gene sequences. The intra-species genetic distance based on K2P was % 0.00, while the average interspecific distance was % 18.2. Phylogenetic trees showed that the studied Anchovies were in two sister clades. The results of this study suggested that the COI gene has the ability to distinguish the fish species. The results of molecular analyses were in accordance with the results of morphology.

This research evaluated the effects of dietary supplementation of commercial Bactocell and D-Pro probiotics on growth performance, survival and carcass composition in giant freshwater prawn Marcrobrachium rosenbergii postlarvae (PL) in a 60 day feeding trial. A total of 600 PLs with mean initial weight of 0.090± 0.004 g were assigned to five treatments each with three replicates in a completely randomized design experiment with 40 PL in each 50 L tank. . Experimental groups including control diet (without probiotic), 0.3 g Bactocell (treatment 1), 0.6 g Bactocell (treatment 2), 0.4 g D-Pro (treatment 3) and 0.8 g D-Pro per kg diet (treatment 4). After feeding trial, growth indices, dietary factors and proximate compositions were analyzed. The results showed that final weight, weight gain, condition factor, survival, specific growth rate and protein efficiency ratio were significantly higher in prawns fed with probiotics compared to control (p

To assess the acute toxicity of colloidal silver nanoparticles (AgNPs) in Nannochloropsis oculata, microalgal cells were exposed to different concentrations of AgNPs for 72 hours and according to OECD 201. Algal cell count was done every 24 hours and average specific growth rate, as well as percent inhibition of the average specific growth rate, were calculated for each concentration. Also, the amount of inhibitory concentrations (IC) and median inhibitory concentration (IC50) of this nanomaterial were calculated according to the percent inhibition of the average specific growth rates and by using the Probit Analysis program. The results showed that even at the lowest concentration (0.005 mg/L), silver nanoparticles reduced the growth of Nannochloropsis microalgae. Accordingly, No Observed Effect Concentration (NOEC), Lowest Observed Effect Concentration (LOEC), and IC50 of this nanomaterial for tested microalgae were 0.001, 0.005, and 0.036 ± 0.009 mg/L. On this basis, and considering the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), tested AgNPs are classified as “category acute 1” or “very highly toxic” for N. oculata, so any accidental or intentional release of AgNPs containing wastewaters to aquatic ecosystems may cause irreparable effects on the aquatic environment.

Regarding the importance of studying inland water fishes specially the fish living in qanats, some morphology characteristics, length-weight relationship and growth type of Turkmenian loach Paraschistura sargadensis living in Aran qanat, Baft city were assessed by standard protocols. Range of total length was 25.1-51.38 mm, standard length was 20.65-43.10 mm, fork length was 23.41-46.85 mm, body depth was 2.97-4.66 mm and the weight of fish was 0.12-0.81 g. Total length- weight relation was as W=0.000012TL2.86 with r2= 0.978. According to the results of Pauly test, the value of “b” obtained had a significant difference with value of “3” and hence, the growth type of this species is allometric in Aran qanat.

Considering the growing production, consumption of nanomaterials and their probable release into the aquatic ecosystems and study on the toxic effects of these materials are of critical importance to aquatic organisms. In this study, the acute toxicity of silver nanoparticles (AgNPs) produced by a physical method (laser ablation) was examined on Gambusia fish. Acute toxicity tests were planned and performed according to standards of Organization for Economic Cooperation and Development. To do this, after 96 hour exposing fish to different concentrations of silver nanoparticles, mortality data were analyzed using probit analysis program and lethal concentration values were calculated. Accordingly, the 96-hour median lethal concentration (LC50) of this AgNPs colloid for Gambusia fish (Gambusia holbrooki) estimated to be 0.016 mg l-1. On the basis of this value, mentioned nanomaterial is classified as a highly toxic chemical and in the case of release into the environment could have adverse effects on aquatic organisms. Preventing from intentional or accidental release of AgNPs into aquatic ecosystems should be, therefore, considered further.

Rising trend of production and use of nanoparticles can lead to the possibility of their release into aquatic environments. Therefore, knowing toxic effects of these materials on aquatic organisms is of great importance. The objective of this research was to study the acute toxicity of colloidal silver nanoparticles (CAgNPs) through determining the lethal concentrations in the euryhaline teleost, Aphanius dispar. Toxicology experiments were conducted for 96 h in freshwater according to the OCED 203 standard protocol. Fish mortality was recorded every 24 h after exposure to concentrations of CAgNPs 0, 5, 10, 20, 30, 40 and 50. The actual concentration of silver in each aquarium was measured by atomic absorption and based on the actual concentration data on mortality were analyzed using the US EPA Probit analysis program. Based on the results, the estimated 96h LC50 of CAgNPs was 10.631 mg/L. Accordingly, the tested CAgNPs should be classified according to GHS (Globally Harmonized System of Classification and Labeling of Chemicals) as “category acute 3” for Aphanius dispar this means that presence of CAgNPs in the environment of this fish is detrimental and, therefore, its release into the aquatic ecosystem should be carefully considered.

With regard to the importance of polychaete Perinereis nuntia in diet of shrimp broodstock, achieving its breeding and culture bio technique is an important goal in shrimp industry. For this purpose, usage of diets inducing the highest growth and the lowest mortality is of importance. The effect of four different dietary treatments including commercial shrimp diet- Biomar, Lansy shrimp diet containing Spirulina micro algae, Enteromorpha green algae and Ulva green algae on growth and survival of this species was examined at 35 ppt salinity in present study. A number of 480 Polychaetes with average initial weight of 0.01 ± 0.002 g in four treatments and three replicates were fed the diets for three months. The results indicated significant effect of diet on final weight and survival of Polychaete. Treatments fed with commercial shrimp diet and diet containing Spirulina had higher final weight than treatments fed with Enteromorpha and Ulva algae (P

As pearling has been banned since 2006 in Persian Gulf, growth and mortality rate of Mohar pearl oyster in its old habitats was surveyed in present research. For early survey and identification of habitats of Mohar pearl oyster Pinctada radiata, primary sea tours in coastal waters of Lavan Island, were done. Two habitats were identified and sampled seasonally from autumn 2011 to summer 2012, to investigate Pinctada radiata stock condition. Belt transects and random quadrates method was used in this sampling. Infinity length, L∞, in Lavan No. 1 (Dardoor) and Lavan No. 2 (Hedabad) habitats was 89.16 and 87.68 mm. Growth constant, K, estimated 0.34 and 0.44 year-1in that two habitats. The amount of t0 for oysters in Dardoor and Hedabad habitats was -0.36 and -0.28 year and tmax was estimated equal to 8.46 and 6.54 year respectively. Natural mortality constant, M, was 0.63 and 0.75 year-1 respectively. Analyses of growth constant, K, revealed that this figure has decrease in these habitats in recent years. Investigation of recruitment plots indicated semi continuous pattern of recruitment in pearl oysters, demonstrating that reproduction occurs in almost throughout the year although two peaks of reproduction were observed in summer and winter.

Present study aims to determine suitable dose of inulin in Piaractus brachypomus fry diet and its effect on growth, survival and some hematologic indices in this species. In this research, one basic diet as control and three experimental diets including three levels of 1, 2 and 3% inulin each with three replicates were considered. Fish with mean initial weight of 2.31±0.14g were fed with experiment diets for 8 weeks. Results showed that the level of 2% prebiotic inulin in diet caused the increase of final weight gain and specific growth rate and improved food conversion rate (P

Mohar pearl oyster Pinctada radiata is the dominant economic species of pearl oyster in the Persian Gulf, particularly along the Iranian coastal waters. As pearling has been banned since 2006, stocks of pearl oysters has not been investigated during these years. For this purpose, conditions of natural habitats and stocks of Mohar pearl oyster in its old catch sites were surveyed in the present study. Shallow waters around the Lavan island were searched through diving and two habitats of Mohar pearl oyster, namely Lavan No. 1 (Dardoor) and Lavan No. 2 (Hedabad), were detected. Area of Dardoor and Hedabad habitats was calculated equal to 60 and 15 ha, respectively and Mohar pearl oysters had the highest distribution in depth ranges of 7 to 12 m and 5 to 11 m, respectively. Total stocks of Dardoor and Hedabad habitats was surveyed about 357000 and 61500 pearl oysters of which 11% and 17% of oysters were catchable, respectively. Catch per unit of area in Dardoor and Hedabad habitats was estimated equal to 0.6 N/m2 and 0.4 N/m2 and catch per unit of effort was calculated equal to 119 N/hr and 82 N/hr, respectively. Biomass rate in these habitats was obtained equal to 4620 and 1163 kg, respectively. Results of this research revealed that the area, the amount of stocks and catch per unit of area of habitats has decrease in the recent years. Although the pearling has been banned in this region in the past seven years, restocking has been conducted slowly.

One of the major issues in aquaculture is to keep balance between growth rate of fish and optimal use of consumed food. L-carnitine is considered an effective food supplement for fish growth. Sobaity seabream is one of the commercially important species in the Persian Gulf that is highly considered in aquaculture too. Growth indices and survival rate of 240 Sobaity fingerlings with mean weight of 3.01±0.03g were investigated during ten weeks after supplementing diet with L-carnitine. The study was performed with four levels of 0.0, 500, 1000 and 1800 mg L-carnitine per kg of diet each with 3 replicates based on the satiation. Sobaity fingerlings fed the level of 1000 mg L-carnitine per kg of diet had the highest growth rate and the lowest feed conversion rate (P

Length weight relationship, condition factor and length at first maturity of Indian halibut Psettodes erumei were investigated in the Persian Gulf by monthly sampling of 30 fish from March to February 2012. Mean value of total length and weight were 38.68 ± 9.39 cm and 986.92 ± 756.79 gr, respectively. Maximum and minimum values of total length were in August (44.43 ± 6.37 cm) and March (23.27 ± 2.32 cm), respectively. Maximum and minimum values of body weight were in January (1540.73 ± 1358.69 g) and March (134.52 ± 40.13 g), respectively. Analysis of length frequency distribution showed that the most frequent length category was the category of 39-42 cm with 56 fish that is equivalent to 17.89% of total samples. 52.4% of caught fish had a total length less or equal to 39 cm. Total length-weight relation in Psettodes erumei was calculated as W=0.005TL3.284 with R2= 0.973. Regarding significant difference between the estimated b and the number 3 with 0.95% confidence, the growth type of this species was determined to be positive allometric in the Persian Gulf. Condition factor was calculated to be 1.57 in Psettodes erumei in the Persian Gulf waters. Condition factor has increased from March to July and then decreased to December. Length at first maturity was estimated to be 39.3 cm of total length in Psettodes erumei.

Low survival at early stages of life is of great concern for fish culturists. Considering the effects of herbal immunostimulants on innate immune response and growth improvement of aquatic animals, the impacts of a native herb of Hormozgan province named Zhumeria majdae extract on growth indices and immunology of catfish fingerlings Pangasianodon hypophthalmus with mean weight of 1.27±0.24 were investigated. Fish were fed diets supplemented with Z. majdae extract at 0 (control group), 150 (treatment 1), 300 (treatment 2) and 600 (treatment 3) mg/kg diet for 45 days. After the feeding trial, fish growth, hematology and immunology parameters were analyzed using Duncan test. Fish growth parameters including FER, DGI and SGR were not significantly different between treatments at days 15, 30 and 45. Survival percentage in all treatments supplemented with herb extract was 100%. The highest haematocrit level was at treatment 3 (46.67±7.64%), The highest number of RBC (3.10±0.6×106) and WBC (7.40±0.3×103) and also the highest amount of total protein and albumin was at control group, the highest amount of hemoglobin, MCV and MCH was at treatment 1 and the highest NBT and MCHC value was at treatment 2. In white blood cell differential count, the highest percentage of neutrophil was observed in control group, the highest percentage of lymphosyte in treatment 1 and the highest percentage of monocyte in treatment 3 .The amount of lysozyme was significantly different with the highest amount at treatments 3 and control, respectively and the lowest in treatment 2 (p

The impact of rainbow trout farm effluents on water physico-chemical parameters of Ryjab River was investigated. Five stations were considered at different parts of the river. Station 1 located at the headwaters of the river, station 2 after nearly 30 percent of fish farms, station 3 after 60 percent of fish farms, station 4 after the last fish farm and station 5 located one kilometer after the last fish farm. Water physico-chemical parameters including temperature, oxygen, pH, carbon dioxide, electrical conductivity, ammonia, nitrate, nitrite, phosphate, total dissolved solids, biological oxygen demand and chemical oxygen demand were measured every 15 days at different stations from March to February, 2012. The results showed that there was no difference between the study stations in terms of nitrate rate (P>0.05). The fish farm effluent had significant impact on Ryjab water parameters including pH, CO2, oxygen, alkalinity, the total hardness, the electrical conductivity, ammonia, phosphate, TDS, BOD5 and COD (P 0.05). In conclusion, the effluents of rainbow trout farms have caused the pollution of the Ryjab River and the water physico-chemical parameters have changed.

This study was conducted to investigate the effect of rearing at differing densities and dietary supplementation with vitamin E on growth indices, survival and carcass composition in fingerling rainbow trout in a 6-week trial. Rainbow trout juveniles with initial body weight of 9.6 ± 0. 69 g at two densities of 50 and 100 pieces per 50 liter were fed two diets with the same protein and fat content. Experimental diets were diet 1 without adding vitamin and diet 2 with adding 600 mg/kg of vitamin E. A total number of 900 rainbow trout juveniles in four treatments, each in three replicates as T50(0) (with the density of 50 and feeding with diet 1), T100(0) (with the density of 100 and feeding with diet 1), T50(E) (with the density of 50 and feeding with diet 2) and T100(E) (with the density of 100 and feeding with diet 2) were randomly distributed. After 6 weeks of feeding, growth performance, feed conversion ratio and viability were significantly differentbetween treatments (P˂0.05). T50(0) and T50(E) had higher weight gain, specific growth rate and viability than T100(0) and T100(E) (P˂0.05). Feed conversion ratio was higher in T100(0) and T100(E) (P˂0.05). Carcass composition was not significantly differentbetween treatments (P˃0.05). The results showed that dietary vitamin E supplementation in rainbow trout juveniles did not have significant effect on growth, feed conversion,survival and carcass composition but density was a key factor in growth, feed conversion ratio and survival.

Some reproductive biology features of Yellowfin Seabream Acanthopagrusl atus including gonadosomatic index, hepatosomatic index, sex ratio, macroscopic and microscopic survey of gonad development, frequency of different maturationstages and absolute and relative fecundity were investigated. Thirty fish per month were sampled during September 2011 to August 2012 in coastal waters of Hormozgan province. The most frequent maturation stage at 4 was in March and April and the highest gonadosomatic index was in April with 7.48 and the lowest value was in August with 0.28. The trend of gonadosomatic index indicated that the spawning season ranges from January to the end of Aprilwith the peak in April and in a batch spawning mechanism. Hepatosomatic index revealed a significant increasing trend from December and reached to the peak in March and April. Considering the sex reversing of male to female in this species, it was confirmed that they are protandric hermaphrodite. Sex ratio showed the value of 2.7 which indicates a significant difference between the number of males and females (P< 0.05). Maximum and minimum values of absolute fecundity were estimated 2530780 and 1431520 eggs, respectively. The highest and least amounts of relative fecundity were 3778 and 2373 eggs, respectively with maximum and minimum total length and weight of 37.2 and 21.4 cm and 965.5 and 378.9 gr, respectively.

The improvement of immune system and increasing growth and survival of fishes especially at early stages is important for fish culturists. Considering the effects of herbal immunostimulants on innate immunity and growth of fish, the impacts of dietary Salvia macrosiphon extract on some growth and immunological parameters of fingerlings Pangasianodon hypophthalmus were investigated. Fishwith mean weight of 1.27±0.24 were fed diets supplemented with S. macrosiphon extract at 0 (control group), 150, 300 and 600 mg/kg diet for 45 days. After the feeding trial, fish growth and hematological parameters was analyzed using Duncan test at 95% confidence. Fish growth parameters were not significantly different between treatments at days 15, 30 and 45. All the treatments showed almost 100% of survival. The lowest haematocrit level was observed at control (41.33 ± 4.16%), while the highest (44.56± 2.00%) was at 300 mg/kg diet of Salvia extract. Mean number of WBC and RBC was not different between the treatments. WBC differential count revealed that the highest percentage of neutrophil was in treatment 2, the highest percentage of lymphosyte in treatment 1 and the lowest percentage of monocyte in treatment 3. The mean values of MCV, MCH, MCHC, Hemoglobin, Albumin and total protein had no significant difference between the treatments. The amount of lysozyme was significantly different with the highest amount in treatments 2 and the lowest in treatment 3 (p

Black Pomfret (Parastromateus niger) is one of the commercially important pelagic fishes of the southern coasts of Iran. Its stocks are decreasing due to over exploitation, pollution and lack of fishing management programs. In order to assess the population size of this species and to preserve its valuable genetic resources, genetic structure of 32 fish samples was investigated using AFLP markersin Bandar Abbas, Bushehr and Abadan locations from coastal waters of the Persian Gulf. The results showed a total of 205 AFLP bands of which 37 bands were polymorph. The percentage of polymorphic loci in samples of Bandar Abbas (81.08%) was low compared to Bushehr (94.59%) and Abadan samples (86.49%). Nei’s genetic diversity and Shannon’s index were lowest and highest in Bandar Abbas and Bushehr populations, respectively. AMOVA revealed that 86% of genetic variations were within populations and 14% among them. With regard to the amount of Fst (0.09- 0.18) and limited gene flow (1.09- 2.54) between populations, it can be concluded that there is probably three different populations of black Pomfret in Bandar Abbas, Bushehr and Abadan locationsin Persian Gulf.

The simple linear model and catch data from Caspian Sea during a decade were used to assess the state of the fishery in this region. Also fishery trends were analysed to determine the catch fluctuation during the period. Fishing potential of the species for the following year was predicted. Catch trend analyses of bony fishes showed incremental or decreasing patterns for different species. However, the mean catch of all species revealed a sustainable trend. The total catch of sturgeons and Kilka has been reduced as well as catch composition. However, Persian sturgeon and common Kilka sprat are the dominant catches of these groups. Hatchery activities and releasing of Persian Sturgeon juveniles into the Caspian Sea and ecological changes after Mnemiopsis leidy entrance seem to be the main reasons for this situation.