Nursery grounds of green tiger prawn (Penaeus semisulcatus, De Haan, 1844) in Bushehr coastal waters of the Persian Gulf, Iran

Nursery grounds of Penaeus semisulcatus were surveyed in the main coastal prawn catching areas of the Bushehr waters, Persian Gulf, from July 2003 to March 2005. Sampling stations were selected in waters less than 10m deep and juveniles were collected using a small vessel powered by a 150 hp outboard engine that was equipped with a small beam trawl net with 10 mm mesh size. Prawns less than 15 mm carapace length were classified as juvenile. The catches of P. semisulcatus juveniles were abundant at only a few sites in the shallow waters around southern (Motaf) and middle (Helaileh) regions of the studied area. The maximum number of juveniles was seen in July and November 2003 that amounted to 596 and 24 specimens, respectively. In April and June 2004, only 43 and 85 specimens were recorded respectively. Juvenile abundance was higher in vegetated sites as compared to other sites during this study. The study supports the fact that the extensive shallow reef and open flat coastline areas that are covered with grass and algae communities are critically important for the prawn and should therefore be protected from pollution, fishing gear damage and industrial development

Stock assessment of the razor clam (Solen brevis Gray, 1832), in Bushehr province coasts, Persian Gulf

Stock assessment of edible bivalve, Solen brevis was carried out in Bushehr shoreline areas (50 21 E - 29 41 N to 52 41 E 27 17 N) throughout the period of September 2008 till September 2009. The objectives of this study were identifying the distribution, and estimating the abundance, growth parameters and natural mortality of the bivalve. Solen specimens were collected monthly in Bupatil area and from three other areas at low tide. On each transect one or two quadrats (0.25m 2) were placed at random. To estimate the stock abundance, the mean number of shells in each quadrat was regarded as an estimate of stock mean. Length frequency was used to estimate growth and natural mortality parameters. Data analysis was conducted with the most recent version of LFDA statistical software. The main distribution areas for live edible bivalve, Solen brevis, were located at Bupatil, Gasir, Kaloo, Piazi and Bordekhoon. The mean (±SD) abundance in Bupatil was estimated at 3.25 1.1 shells per quadrat with a maximum peak in October and minimum in August. The estimated growth parameters of this species was, K = 0.7 Year-1 , L = 120 mm and t0 = -0.35. Natural mortality rate (M) was estimated at 0.26 and the calculated maximum age (Tmax) was 54 months

Fisheries management of the green tiger prawn (Penaeus semisulcatus, De Haan,1844) in Bushehr waters, Persian Gulf

Stock assessment and the opening and closure seasons of the green tiger prawn were surveyed in Bushehr waters from July 2004 to September 2006. The study area encompassed Motaf area (27 degree 30' N" and 51 degree 30' E) to Daylam waters (30 degree 00' N and 50 degree 00' E) the northern part of the Iranian waters of the Persian Gulf. Assessment was conducted using 45 stations on 15 transect in water depths less than 10m, 10-20m and 20-30m. Sampling was done by bottom trawl net. Results showed that the shortest mean length of the prawn were 11.3, 11.8 and 11.9cm in the years 2004, 2005 and 2006, respectively. Also, the maximum catch per unit effort for the prawns in these years was foun d to be 10.8, 14.7 and 9.7kg per hour. At the opening of fishing season in the years 2004, 2005 and 2006, the CPUE of the prawn fishing launches were 100, 150 and 120kg per day. Based on length frequency of the green tiger prawn, the opening times of prawn fishing was proposed to be 22, 11 and 20, August of years 2004 , 2005 and 2006, respectively. Also, the closure times were derived from the shrimp commercial catch data and defined to be 25, 27 and 28 of September in 2004, 2005 and 2006, respectively. Investigation of the shrimp stock density in Bushehr waters shows that the green tiger prawns enter the fisheries areas from the southeastern parts of Bushehr waters. The Motaf, Nakhilou, Ras-e-khan and Mond River are the areas that green tiger prawn schools are first emerged in the Bushehr province waters

Study on banana prawn (Fenneropenaeus merguiensis) movement in the Hormozgan waters in the northern Persian Gulf

This research was carried out in Strait of Hormuz in 2020. The present study aimed to investigate the migration and growth pattern of tagged shrimps in the study area. Bloodstock shrimps were reared in June (2010). About 50000 juvenile shrimps were tagged by red color florescent elastomeric tag and released in the estuaries of Tiab, Kolahi and Koolgan at night in July 2010. Local people were informed through posters describing the tagging program, as well as articles published in a local magazine. A tagging program film was broadcasted on local television three times prior to the shrimp fishing season and during shrimp catch period. In the catch season, September and November months, 11 tagged prawns (0.022%) were recaptured. Movement direction of tagged prawns was northwesterly of deeper waters of releasing areas. Speed was recorded at 0.33-0.33 km/day and tagged prawns were recaptured 46 km from the released locations. The mean (±SD) weight of released banana prawns and the average weight of the recaptured prawns were1.2±0.2 g and 22.06±4.9 g, respectively. The growth rate of recaptured prawns was 16-26 g and growth speed was 0.88-1.41 g per week. In the study area, the major sea current was from the Oman Sea to the Persian Gulf through Strait of Hormuz probably influencing the pattern of banana prawn movement in Hormozgan area

Population dynamics of green tiger shrimp (Penaeus semisulcatus) in the Persian Gulf (Bushehr Waters)

The population dynamics of Penaeus semisulcatus was studied out in the Persian (Bushehr province waters) through a series of research cruises conducted by the R/V Lavar. The growth and mortality parameters for both sexes were estimated by FLEFAN and FISAT computer programs. The following results obtained for males: L∞=37mm, K=1.8per year, t_0=0.3, M=2.8, F=4.5 and Z = 7.3. These results for females were as follows: L∞=49 mm, K = 2.6 per year, t_0=0.6, M=3.2, F=6.7, Z=9.9. According to obtained results, the exploitation rate for males and females were 0.61 and 0.67, respectively and the ϕ-value was estimated 7.8 for males and 8.3 for female. The sex ratio Was M:F-1:1 and the spawning season was from January to March with the main peak in January. The maximum age for males and females were determined 21 and 19 months respectively

Short communication: Population structure of green tiger prawn, Penaeus semisulcatus (De Haan) in Bushehr waters, Persian Gulf

Information on the population genetics of shrimp species in the Persian Gulf is scarce. There are few electrophoretic based study therefore the aim of the present study was to investigate genetic variation among population of the green tiger prawn, P. semisulcatus, in Bushehr waters, Persian Gulf. This is the first study on this species by RAPDs in this area. The input of research in the field of genetics has resulted in new technological advances that have improved the economic gains of shrimp production. A total of 50 P. semisulcatus were collected by R/V Lavar II from two major shrimp localities, Halaileh and Daylam, in August and September 2004. Genomic DNA was extracted from muscles using the modified mini preparation method. A set of 9 primers (Diotech MWG) were used to detect polymorphism among populations. The software package RAPDistance version 1.04 was used to analyse the data

Population genetic study on two commercial shrimp species and determining of DNA-Barcoding of 6 – 8 species by partial sequencing of mtDNA using molecular method (PCR-Sequencing)

Barcodes are short segments of DNA that can be used to uniquely identify an unknown specimen to species, particularly when diagnostic morphological features are absent. These sequences could offer a new forensic tool in plant and animal conservation especially for endangered species. Ideally, barcodes could be used to positively identify illegally obtained material even in cases where diagnostic features have been purposefully removed or to release confiscated organisms into the proper breeding population. In the present study molecular data were used besides the morphological ones to introduce a specific barcode for six selected species of Shrimp. Based on the previous phylogenetics study, it has been proved that the mitochondrial COI gene in crustacean is a good discriminative marker at both inter- and intra-specific levels. In this regard, six species of shrimp (Fenoro penaeus indicus, Fenoro penaeus merguensis, penaeus semisulcatus, Metapenaeus affinis, Marsupenaeus japonicas, Fenoro penaeus penicillatus were collected from the Persian Gulf and Oman sea. After identification, the total DNA was extracted; COI gene was first amplified and then sequenced for each species. Finally the collected data were analyzed with the specific phylogenetic software. Molecular analysis revealed some degree of interpopulation differences but six good species were recognizable based on COI sequences. Also for population study molecular data of two species Penaeus semisulcatus and Metapenaeus affinis were analysed base on COI RFLP and 16SrRNA sequences respectively. The results would be helpful to protect shrimp species

Biomass estimation and density of green tiger prawn (Penaeus semidulcatus, De Haan, 1844) in Bushehr province, Persian Gulf

Biomass and density of green tiger prawn were estimated in Bushehr waters during July - August in 2004, 2005 and 2006. Studied area was located from Motaf area (27 30 N and 51 50 E) till Daylam waters (30 00 N and 50 00 E) the northern part of the Iranian waters of the Persian Gulf with about 2000 nm limit. 45 stations in 15 transects were selected in the waters less than 10 m deep, 10-20 m and 20-30 m. Sampling was done by bottom trawl net. The maximum catch per unit effort (CPUE) of green tiger prawn was obtained in south area. From middle to end of shrimp fishery season (August) CPUE increased in the north area. Based on our estimations, the initial total shrimp biomass estimated in the south area was 674, 1024 and 873 tons in 2004, 2005 and 2006, respectively. The percentages of green tiger prawn in biomasses were 77, 75 and 86 in above mentioned years, respectively. Investigation of the shrimp concentration in the Bushehr waters showed that the green tiger prawns entered the fishing grounds from the southeastern parts of Bushehr waters, and Motaf, Nakhilu, Rase khan and Rod mond were considered as initial appearance zones. Dense schools of green tiger prawns were observed above 10 meter than deep waters in late June and early July. But in late July, the 20-30 m of deep water contained dense shrimp schools

Growth parameters and maximum age of prawn, Penaeus semisulcatus (De Haan) in Bushehr waters, Persian Gulf

Carapace length frequency data of green tiger prawn, Penaeus semisulcatus, were monthly collected from 50 stations along the coastal waters of Bushehr, Persian Gulf, during January 2003 to March 2004. FiSAT program was used to analyse a total of 535 shrimps including 292 females and 243 males, for the relationships of total length, weight and carapace length. The L∞ and K for males were estimated at 38mm CL and 1.6 year-1 and for the females were 50.40mm CL and 2.20 year-1, respectively. Maximum age (Tmax) was 20 months for the males and 15 months for the females. The growth of the shrimp was found to be rapid during summer and autumn and negligible during winter and spring

A study on the diversity and abundance of ichthyoplankton in coastal waters of the Kharg and Dylam (Persian Gulf)

The present investigation was undertaken to identify fish larva and estimate their abundance, diversity and evenness indices. Twelve stations were sampled monthly during daytime hours by Bongonet in the kharg and khargoo regions of Persian Gulf from January 2005 through December 2006. Forty family of fish larva were identified, Families of Silaginidae, Clupeoidea, Blenidae and Athrinidae consisted of more than 61 percent of all specimen; The abundance of specimen were more during spring through fall months and least during winter. The number and abundance of identified families varied from cruise to cruise and station to station; the average amount of diversity, Species Richness and evenness in investigated region were computed 1.93, 12 and 0.68, respectively. Temperature and salinity of water during this study were between 16-34°C and 35-42 gr/lit. There weren’t any significant correlation between fish larva indices and above factors