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Community structure and biodiversity of benthic macro fauna in around pen culture of Sturgeon fish in Gorgan Bay were studied for period of one year from August 2015 to July 2016. Seasonal samplings were carried out at 5 stations in 3 transects. In addition, depth (D), water temperature (Toc), dissolved oxygen (DO); pH, total dissolved solid (TDS), biological oxygen demand (BOD5), chemical oxygen demand (COD), phosphorus (PO4-3), nitrite (NO2-) and total ammonia (NH3+) were measured in each station. Results of season variations of Physico – chemical factors of water showed that, there were no significant differences between PO4-3 (p>0.05). However, there were significant differences between BOD5, COD, NO2-, NH3+ and TDS (p

Seaweeds contains different types of polysaccharides with high abilities. The aim of this study was to determine the potential of fucoidan polysaccharides for wound-healing properties. Fucoidans of two species of Padina (P. tetrastromatica and P. boergesenii), collected from the Persian Gulf northern coastal area, were extracted and analyzed using high-performance anion-exchange chromatography. Purified fucoidans were used to prepare a 2% topical ointment. Under aseptic conditions, two identical paravertebral full-thickness skin wounds (either by burn or excision) were made in 40 anesthetized male rats allocated into 4 groups. Either fucoidan ointments or the vehicle (ointment base) were applied to rats' wounds twice daily for 14 days. In addition to the examination of wound area reduction (days 3, 7, 10, and 14) and histopathological assays (days 7 and 10), tissue specimens were taken to the laboratory. Fucoidans obtained from both seaweeds induced significant wound area reduction compared to the vehicle at some time points after treatment. Histopathological examinations showed improvement in some healing signs including angiogenesis, collagen fiber formation, and epidermis formation. In conclusion, both species of Padina have significant wound-healing effects and fucoidan polysaccharides are the active constituents for this healing property. However, fucoidan obtained from P. boergesenii showed superior effects in this regard.

In this research, size selectivity for narrow-barred Spanish mackerel (Scomberomorus commerson) and other species such as Indo-Pacific king mackerel (Scomberomorus guttatus), Longtail tuna (Thunnus tonggol),Kawakawa (Euthynnus affinis), Talang queenfish (Scomberoides commersonnianus) and John's snapper (Lutjanus johnii) were investigated in mesh sizes of surface, mid-water and bottom drift nets in coastal waters of Bandar Abbas and in the western part of Hormozgan province (fishing ports of Gong and Bustaneh), as well as of catch composition from the fisheries. The data required for the relevant analysis was collected for the years 2012-2014. In order to determine the size selectivity of the investigated species, cumulative probability distributions of retention girth (operculum and maximum girth) at length was used. The results indicated that there is a linear relationship between length (fork length or total length) and transvers morphometric parameters in six positions of girth at fish species. Seven types of gillnets with stretched mesh sizes of 70, 76, 79, 101, 114, 132 and 165 mm and different technical characteristics were investigated for size selectivity of S. commerson, in which the optimal length were 38, 44, 49, 63, 74, 86 and 100 cm FL in the respective meshes. The capture processes of S. commerson was mostly in wedging in the all mesh sizes, whereas in the other species, depending on the morphology of fish, the retention method was different. The comparison of length frequency distribution of kingfish with mean length at maturity (Lm50%) indicated that, depending on mesh size, the frequency of the immature fish in the catch was between 4 and 100%. On the basis of optimal length at mesh size, the minimum legal mesh size of kingfish was estimated as 162 mm. Size selectivity curve was also represented for other species, which depending on fish morphology the model was inadequate in fitting the data. The results from the catch composition showed that the species diversity is different by fishing method. In mesh sizes of 70, 76 and 79 mm, the kingfish was captured in target and bycatch species depending on time by the surface drift gillnet fishery operated by the fishing boats. In this type of gillnet fishery, bycatch accounted for more than half of the total catch in which some of the species was important economically. Catch composition in gillnet fishery operated by dhows was different depending on fishing method. At the first step, it is necessary to impose a ban on gillnets with mesh sizes of 70, 76 and 79 mm in second half of the year. In the next step, for establishing the regulation on minimum legal mesh size of kingfish, it needs to do further study in seas trails aimed at determine the appropriate mesh size. Also, in the multispecies fishery, it is necessary to do a research for optimization of mesh sizes of gillnets and to implement minimum legal mesh size for the main target species. Iranian Fisheries Science Research Institute Published

This document analyses some population parameters of Yellowfin Tuna (Thunnus albacares) taken by drift gillnet operation from southern part of Iranian coast in the Oman Sea during 2007 to 2009. A total of 9,345 specimens of T. albacares were sampled in the size range of 37 cm to 172 cm fork length (FL). The mean length was estimated to be 86.12 cm. There was influence from seasonal variation on the length distribution of individuals, and it showed a tendency of gradual increase in the model length with the fishing season. The temporal change in length distribution is more likely to be an indication of feeding migration of medium-sized Yellowfin Tuna from the western Indian Ocean into the Oman Sea during January to June. The statistical analysis of lengthweight relationship was achieved by sex. The electronic package "ELEFAN I" was chosen for describing the species' von Bertalanffy growth equation; parameters were L∞= 183.3 cm, K= 0.45 year-1, and t0= -0.184 year. Natural mortality (M) was 0.48 year-1, fishing mortality (F) 1.56 year-1, and total mortality (Z) 2.04 year-1. The exploitation ratio (E) was as high as 0.76. For sustainable exploitation of T.albacares, a decrease in fishing effort of the gillnet fishery would be alternatively an effective measure to decline the fishing pressure on the stock, and to prevent the probably overfishing events.

Tuna catches in Indian Ocean have been increasing since 1980 by entrance of purse seiners into the area, making their catches about 10 times over 25 past years. Remarkable catches of the fish, especially the three main species yellowfin, Thunnus albacares, bigeye tuna, Thunnus obesus, and skipjack, Katsuwonus pelamis, have raised concern about overfishing of the stock. In spite of the importance of the valuable fish, the present stock assessment methods are not able to estimate population dynamics parameters precisely in order to understand the real status of tuna stock, and for this, presently precautious strategies are used for fishing management. In 1991, scientific committee of IOTC agreed that conducting a planned tagging project in large scale is the most effectiveness tool for obtaining the required data to improve the stock assessment of the main tuna species. The whole plan of the tuna tagging in Indian Ocean have been developed in two phases: pilot study in small scale, and the main tagging phase in large scale. After achieving successful results from the pilot study in 2001, executive programme for tagging operations in large scale known as Regional Tuna Tagging project-Indian Ocean (RTTP-IO)were developed for over two and a half years for the three main species above. The project was started in May 2005 and ended in 3 rd September 2007. The study area included Seychelles, Mozambique Channel, Kenya, Tanzania waters and Arabian Sea (Yemen and Oman). The objectives of the RTTO-IO were: To tag at least 80,000 fish from the main species, to achieve remarkable recovery (at least 15%), to study migration routs between different areas and stock structure, and to estimate growth rates. The present report was resulted from participation of research cruise for tuna tagging in Oman Sea waters in the line with RTTP-IO. In this cruise, 2835 of yellowfin were captured by two pole and line vessels using live bait, and then released after tagging. Different tagging techniques used in the project were: Conventional tagging (Single and double tagging), Otolith tagging, electronic tagging. The required descriptions for different sections including live bait fishing, capturing of tuna by pole and line fishing and different tagging techniques are given. Since the beginning of the RTTP-IO until the end of executive period around 170,000 tagged tuna from the main target species were released in Indian Ocean, which up to now 9.8% of the fish were recovered. The number of 8 tagged yellowfin was also recovered by Chabahar local fishermen in Oman Sea which the data in details are presented. Moreover, more information on the recoveries obtained from the RTTP-IO up to July 2007 is given. Iranian Fisheries Science Research Institute Published

Collecting of biometric parameters and catch and effort data were made for yellowfin and skipjack tunas from artisanal gillnet and industrial purse seine fisheries during the years 2002-2004 in Oman Sea along Sistan and Balouchestan coastal waters. The previous available data was used for the purpose of better monitoring the resources. The frequency of maturity stages and GSI values obtained from yellowfin showed a spawning period from Febraury to May, peaking in April-May. For skipjack, the data indicated a long spawning period which beganed in December with peaking in April-May. LM50% was obtained as 83.1 and 62.4 for yellowfin and skipjack tunas respectively. Sex ratio by size group showed a predominance of males with larger fish. Analysis of stomach contents showed a significant proportion for the both species. The composion of food contents by occurrence method revealed that fish were the most dominant food items by year for the specise. Presence of squilla, crabs, shrimps (Larval stage), belonging to Peneaidea family, in large quantities were the obivious food items so that they had not been reported by previous studies. Blooming of squilla, Natosquilla investingatoris, in the western Indian Ocean provided a situaition to be observed in large occurrence in yellowfin and skipjack stomach contents. The ratio was more in yellowfin stomachs when compared to skipjack ones which accounted for 38%, 19% and 35% of the total stomachs studied by the study year. The shrimps prey were only observed in skipjack gut contents (with exception of one case in yellowfin stomach) which were the second major component in 2002 and 2003( 24% and 17% respectively). Comparsion of mean length showed a sharp decrease from 1992 to 2004 for the species. Regarding yellowfin the mean length from 93.2 cm FL in 1992 reached to 83.2 cm FL in 2004 and from 64.95 to 58.51 cm FL for skipjack. In spite of decreasing mean length for yellowfin, the value increased in 2004 in comparsin to 2003 which was in agreement with Indian Ocean data. Comparative analysis of length frequency with LM50% indicated that immature fish were the major part of the catch. There are available information on population dynamic parameters. A comparative analysis of CPUE,s (kg/panel.day) from artisanal gillnet fishery for yellowfin and skipjack tunas revealed a decreased value by fishing craft class in 2005 when compared to 1998 data, but increased in 2003. Incraesed trend of the species catchs by fishing craft class was due to incraesed fishing effort. Analysis of the statistical catch and effort data for the study years, irrespective of fishing craft class, showed that total landings of the species have increased 4.4 fold in spite of attaining CPUE to 7% in decrease which was a consequence of increased fishing effort up to 4.7 fold. The CPUE,s (tons / possitive set) from industrial purse seine fishery increased in 2003 and 2004( 39% and 10% respectively),but declined up to 54% in 2005. The trend is in agreement with purse seine fishery data from Indian Ocean where the increased values were attributed by larger size of yellowfin. The purse-seine fishing ground data revealed that the major sets were made in Persian Gulf, wherase a shift towards Oman Sea in eastern part of Sistan and Balouchestan coastal waters is recommanded to be a suitable fishing area for the first half of year and towards offshore waters in Indian Ocean for the second half of year. For attaining a sustainable fishery system, it is recommanded to regulate the gillnet mesh size and introduce longline fishery in the area along with stoping any further increased fishing effort in artisanal gillnet fishery. Iranian Fisheries Science Research Institute Published

This project was conducted in order to survey on status of stocks of tuna and determine some biometric parameters from industrial and artisanal fisheries in Oman Sea (Sistan and Baluchestan province) during April 1997 to March 2000. It was determined the spawning peaks of yellowfin and skipjack tuna on May- June and on May-June, Jan-Feb respectively, using the data collected from artisanal fisheries during these years. The first length at sexual maturity of females (Lm50%) come for yellowfin, skipjack and longtail tuna when they are 76cm,61cm and 72cm long respectively. Analysis of stomach contents showed that squid was the major components of diet for yellowfin and fish for skipjack, longtail tuna. A comparison of mean length from the same fisheries by two- way analysis of variance based on year and landing showed significant differences by year for yellowfin and skipjack tuna during April 1996 to March 2000. There are available the information on length-weight relationships of three species mentioned the above, as well as growth and mortality parameters of yellowfin and skipjack tuna. It was also determined the distribution of these species by spring, autumn and winter, using the data collected from artisanal fisheries during April. 1999 to March 2000. A comparison of the current distribution was very different with the previous studies in the year 1994-1995. In refer to an increased trend of CPUE of the sampled artisanal vessels (high capacity) in 1999 in comparison with the year 1997, it predicts greater use of the high capacity vessels to harvest more quantities of the resources, especially skipjack tuna. Based on a decreased trend of CPUE of purse seiners in local waters during the years 1996 to 2000, it recommends less activities of the vessels. Iranian Fisheries Science Research Institute Published