Frequency distribution of Penaeus semisulcatus and Penaeus merguiensis in the catch of breeder shrimp trawlers in Jask and Sirik area, Oman Sea

Collection of breeder shrimps in important fishing grounds of Hormozgan province was started in 1994. In this research which was carried out in March, April, June and July 2001 and 2002, we aimed at identifying shrimp species, determining frequency distribution of the species in the catch and evaluating caught maturity stages. We collected data on the catch of artisanal shrimp trawlers on a biweekly basis. Result showed that Penaeus indicus was dominant in the catch while P. semisulcatus and P. merguiensis comprised 20.5-20% and 13.5-19.5% of the catch in Jask and Sirik areas respectively. A Tukey test showed that average carapace length in P. merguiensis and P. semisulcatus caught in Jask were significantly larger than those from Sirik area (p<0.05). Maximum abundance of P. semisulcatus and P. merguiensis spawners was found during March to June in Jask and June to July in Sirik fishing grounds

Biological survey on Penaeus indicus in the Jask area (Oman Sea)

The indian white prawn (Penaeus indicus), as one of the commercially important and dominant species along the East coast of Hormozgan province, is a very potential and prospective candidate species for shrimp farming. Since, there wasn't well enough information about biology of this species from Iranian wateres, therefore. some biological aspects such as growth rate, reproduction behaviour distribution pattern and feeding habits were studied from March 1997 to March 1998. Monthly sampling were carried out from the fishing grounds and estuaries of Jask area in the Oman Sea by small trawlers and beach seines gears. Initial growth 01 male was faster than female, with calculated K=l.5 for male and K=1.3 for female. Isometric growth trend was observed in both sexes. Sexual maturity attained within the first 12 months. Spawners were occured abundantly during post-winter, spring and beginning of summer. Postlarvae and sub-adults were found in the esturies with 25-100 mm length, and high densities were observed around the mangrove's roots. They spend at least 3 to 5 months of their life span in the esturies. Analysis of stomach contents revealed that this species is an omnivore with indicative contents of detritus, polychaetes, crustaceane, bivalves, algae and sand particles, with preponderance of vegetable constituents in the sub-adults and of detritus in adults

By-catch composition of small-scale shrimp trawlers in the Persian Gulf (Hormuzgan Province), Iran

Fishing vessels equipped with bottom trawls cause high amount of by-catch and discards. We investigated the catch composition and by-catch percentage in October - November 2002 during shrimp fishing season in Hormuzgan Province waters. The studied area was located in DarmSoorkh area, east of Hormuz Island and Toola area. Sampling was done using wooden fishing dhows. During shrimp season, 36 hauls with a total catch of 6050kg were treated. The catch composed of 88 species belonging to 50 families of which 67 species were bony fish from 38 families, 9 species were cartilaginous fish from 6 families, and 3 species were mollusks from three families and also 9 species of crustacean were found belonging to 3 families. The percentages of different groups of by-catch and target catch (shrimp) were 49.4% small discards, 18.7% large discards, 4.7% commercial species and 27.2% shrimp. The ratio of total by-catch to shrimp was estimated to be about 2.7 times that of the shrimp

Propagation biotechniques of Penaeus merguiensis in Hormozgan Province, south Iran

Twelve P. merguiensis specimens were collected from fishing grounds of Sirik area in the north of strait of Hormoz. The sampling was carried out from April to November 2003 and the brood-stocks with a mean weight 36.3 grams were transported to Kolahi hatchery center. The samples were kept in two separate 6 ton fiber glass tanks, filled with sea water with a salinity of 32ppt and temperature of 30 degrees centigrade. After spawning, the total collected nauplii from the first and the second tanks were 41800 and 960000, respectively. The survival rate from nauplii stage to PLi5 stage was 31% and 21.2%, for the two tanks respectively. We fed the larva up to N6 stage with Chaetoceros and from mysis to post larvae stages with Anemia. We conclude that Hormozgan province is a suitable area for collection of Banana shrimp brood-stocks and that propagation of the species can be successfully carried out

Monitoring of Cochlodinium polykrikoides blooms as a harmful phenomenon in the Persian Gulf (2010-2011)

The monitoring of the harmful bloom of Cochlodinium polykrikoides in the northern Persian Gulf was studied during 2010 to 2011. The results revealed that in the waters of Hormozgan Province, the Diatoms and Dinoflgellates had the highest frequency. No significant difference was found for amount of nutrients in three sub- regions. The bloom of C. polykrikoides was higher in central sub-region in spring and was occurred in the eastern sub-region in summer, but no mortality of fishes was recorded. In Bushehr Province, four classes of Bacillaryophyceae, Cyanophyceae, Dynophyceae and Prymnesiophyceae were determined. Furthermore significant different values of nutrients were recorded. In waters of Khuzestan Province, different values of NH4 were measured for different months. In total, the measured ratio of N: P in all months was lower than Redfield Ratio (16:1) in which subsequently the environmental condition was not suitable for bloom of C. polykrikoides

Quantitative and qualitative development of shrimp culture in Iran

Primary researches on aquaculture of endemic shrimp species carried out since 1984-5 by Iranian Fisheries Research Organization (IFRO) .After a decade, the condition for extension and development of shrimp culture in the country prepared. Despite huge investment of government for preparation and construction of shrimp sites, only small part of present potential in southern coast of the country is under production. About 18 different shrimp species inhabit in Persian Gulf and Sea of Oman, in which 4 species have larger size, and more abundant, and harvest commercially . Penaeus semisulcatus, Fenneropenaeus merguiensis and Metapenaeus affinis as commercial species distributed throughout of Persian Gulf from mouth of Arvand River in north- west to strait of Hormoz, and also some parts of Oman Sea. While Fenneropenaeus indicus distributed mainly in coastal area of Oman Sea. Shrimp culture begin in Iran by P.semisulcatus, continued by imported Penaeus monodon, and developed by using of F.indicus. After confront to slow growth and viral diseases in 2001 (Khouzestan province) and 2005 (Bushehr Province), at the same time I.F.R.O acquired the bio-technique for production of Litopenaeus vannamei, and hence the condition for introduction the new species to the shrimp culture industry provided. In accordance for development of shrimp culture, I.F.R.O carried out various research activities, and established specific research center for this purpose. Research projects regarding brood-stock management, breeding and larvae production, grow out, water management and disease identification and treatment have been carried, and induced considerable impacts on quantitative and qualitative development of shrimp culture in the country

Biological control of bloom algae in the southern of Caspian Sea

In recent years the incidence of algal blooms caused by Nodularia to become one of the serious problems and is threated life of aquatic organisms in the southern Caspian Sea. Nodularia is a Blue-green algae (cyanobacteria group) and due to production of nodularin toxin is importance. In this study, the first, three species of Pseudomonas including aeruginosa, putida and fluorescens were isolated from Tajan river estuary and identified using biochemical tests and compared to standard species. The trend of Nodularia spumigena biomass (log 5) and pseudomonas species (log 7 and 8) were examined in 30 treatments for 10 days in aquarium scale. Parameters such as chlorophyll a, dissolved oxygen, phosphate and nitrate were tested at different time the same time. The results showed that the decline trend of nodularia in aeruginosa and mixed species treatments were better than other treatments and log 8 of bacterium was also more inhibitory effect than to log 7. Similar results were observed in double layer on agar medium and latter treatments had algaecide effect on nodularia. However, putida and fluorescens treatments had algaestatic properties. Concentration of chlorophyll a, dissolved oxygen and nitrate in all treatments, especially aeruginosa and mixed bacteria have been often decreased (p<0.05). Changes of latter factors in control treatment have been relatively consistent. Although the phosphate changes at different time of relative decline, but nevertheless significant differences were observed. The parameters examined in this study were in direct contact with the algae population and decrease or increase of these factors cause significant change in algae biomass. The conclusion showed that different strains of pseudomonas are able to reduce the population of algae N. spumigena in aquarium scale and the results observed in combination treatment were better than other treatments. The challenge examination of pseudomonas and nodularia in mesocosm scale, evaluation of bacterial metabolites, and also quality and quantity analysis of chemical and biological factors involved in the process is recommended and with achieve reasonable results can be made from this indicator bacteria during algal bloom in the larger ecosystem

Impact assessment of master plan of "attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products" on Bushehr city environment: A case study, Shoghab research station

This study is a part of the national and technology master plan entitled "Attain to technical knowledge of specific pathogen free shrimp production and cut off to dependence on foreign products". The goals of this work were to assess the environmental effects of Specific Pathogen Free shrimp production complex on surrounded region in Persian Gulf (Shoghab) research station in Bushehr city. The environmental impacts were assessed in Persian Gulf (Shoghab) research station in Bushehr city by usage of simple checklist for impacts prediction, and scaling check list for assessment during Feb 2012 till Sep 2014. Flushing the effluents to the sea is the biggest concern of this project that can resulted in health impacts on aquatic and human communities that can be avoided by treatment. Low diversity in activities beside lack of environmental sensitive elements in the region leads us to use of scaling check list for impact assessment. Environmental grade of each activity can be achieved by stratification of them according to their intensity, significance and scale. We reached +320 and -198 for positive and negative points respectively that sounds a clear yes for execution choice

Study and relocation of corals in developing area of Shahid Beheshty port, Chabahar

The conservation of coral colonies is very vital for marine organisms and human. In Chabahar Bay, the coral reefs are in danger of destruction due to the development program of Shahid Beheshti Port. In this project, over 30,000 hard corals were transported to coast of Hotel Lipar an area at a distance of 3.5-4 kms far from Shahid Beheshti Port. Also, the new techniques were used for coral reattachment and transportation. The operation has done within expert divers and consultancy of Prof. Dr. Maikle Risk. Four methods performance as pailots. Since the corals are very sensitive to turbidity and suspended sediments from land reclamation and dredging projects, therefore appropriate measures should be conducted for conservation and recovery of them.37 patches in size 5×10 meters has built with concerete. Diffent sizes of corals were separated by mechanical tools and transported to new sites and reattachment on artificial sea bottom.Three monthes after the last reattachments monitored showed that %96.93 of corals were in good health. This success was the important achievement because of innovating coral carrier and mass coral relocation. At present, the coral relocation is suggested as a good method for recovery of coral reefs after a disturbance in condition of their native habitats

Investigation on the possibility of artificial propagation, cultivation and brood stock management of Vannamei shrimp

Project was carried out at the Gomishan Centre for training and education which is located 15 km far from Gomishan City in the Golestan Province. Prebroodstocks were chosen from ponds (stocking density: 3/m^2). 860 male and 890 female broodstocks were separated and transferred into greenhouse (400 m^2). The average growth rate per day was 0.3 g and survival rate was 90%. After reaching 42 g in males and 52 g in females they were ready for Eyes stalk Brood stocks were transferred into propagation hall in June and after a week females gone under Eyes stalk. 10,890,000 eggs were yielded from 50 females and consequently 7, 187, 0.50 nauplius were produced. Each broodstock spawned 1.34 Times. The maximum hatching was 75% that in was average 64.2%. Mass of Cetocerous Algae was mass produced to be fed for post larvae. Finally 35,000 PL15 were yielded. PL15 were transferred into two half hectare and one 1 ha ponds in July. The stocking density was 18 PL/m^2. Biometric parameters together with air and water temperatures, and pH were recorded daily. Results indicate that the maximum survival rate was 58% (pond No. 5) and minimum was 52% (pond No. 17). The average weight after 101 days cultivating was 23 g which is appropriate. Also the average daily growth rate was 0.2g and the FCR was 1