فهرست مطالب reza abbaspour naderi

The study aimed to compare the catch composition, CPUE, and CPUA of dominant commercial fishes caught by bottom trawl nets (Plan approved by the Fisheries Organization) in different depth layers of The Gulf of Oman,Sistan and Baluchistan Province. This study was carried out during 2 sampling stages in September and March 2018 (fishing seasons). Fishing operations were carried out periodically in layers of 50 meters, 50 to 100 meters, and above 100 meters by the Avash industrial trawler equipped with a bottom trawl net with a power of 2250 horsepower in 24 designated stations (4 times of net hauling per day in 6 days). Based on the calculated CPUE and CPUA results in the first stage, a significant difference was observed between the CPUE and CPUA amounts of John's snapper in the first and second depth layers, and between the CPUE and CPUA amounts of Cobia in the first and third depth layers (P<0.05). Javelin grunter (CPUE: 99.9±45 and CPUA: 2122.6±1132.2) in the first depth layer, black pomfret (CPUE: 53.6±28.7 and CPUA: 738.2±407) in the second deep layer, and longrakered trevally (CPUE: 89.9±40.2 and CPUA: 1181.6±515.7) in the third deep layer had the highest amount of CPUE and CPUA. In the second fishing stage, there was a significant difference between the amount of CPUE and CPUA of the Javelin grunter, Talang queenfish, and Cobia in the second and third depth layers (P<0.05). Javelin grunter (CPUE: 71.2±21.1 and CPUA: 1230.9±428.6) in the second depth layer and longrakered trevally (CPUE: 44.5±9.9 and CPUA: 596.2±129.3) in the third depth layer had the highest amount of CPUE and CPUA. Based on the obtained results, the highest amount of CPUE and CPUA were estimated in the first, third, and second depth layers in the first sampling stage, and in the second and third depth layers in the second sampling stage, respectively.

Cephalopods have short life and global distribution except freshwater that these make them importance for study of their dynamics population. So, the purpose of this study was to estimate the biomass of cephalopods (Amphioctopus marginatus, Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvaucelii, Sepia saya, Sepia prashadi, Sepia omani, Sepia stellifera and Sepia pharaonis) with the catch dynamics model (generalized depletion model) in the NE Gulf of Oman at the end of the fishing season (of bottom trawlers) in the summer and autumn of 2020. The catch data of these valuable fisheries species were obtained through field sampling from commercial fishing in the depths of 74-212 meters by an industrial bottom trawler for 17 consecutive days in the "Gowater-Pasabandar-Beris" fishing grounds (at least 12 nautical miles from the shoreline according to the new move-on rule). The highest total abundance and biomass belonged to Sepia pharaonis by 23431 individuals and 27005.78 kg. Also, the lowest total abundance and biomass belonged to Uroteuthis (Photololigo) edulis by 8 individuals and Sepia saya by 0.397 kg, respectively. The abundance response for most of the stocks was a hyperdepletion (β > 1), while the fishing effort response for most of them was an effort synergy (α > 1). Also, most of the selected models were executed in the presence (open population) of perturbations (pulses). Cuttlefishes had the highest and octopuses had the lowest biomass, respectively. Probably, this study was the first survey of biomass for mentioned species in the waters of the Islamic Republic of Iran - except Uroteuthis(Photololigo)duvaucelii and Sepia pharaonis. The advantages of implementing catch dynamics model based on commercial fisheries activities are practical, operational, and close-to-reality estimates, lack of some costs of scientific surveys, also lack of additional pressure on aquatic resources (especially in nursery grounds) due to the implementation of fisheries activities (fishing operations) within the permitted limits (spatial-temporal).

There is limited information about the relationship between abiotic and biotic variables of the shrimp/prawn stocks in the Persian Gulf. Consequently, the effect of some environmental factors, including temperature, salinity, and depth, on the abundance of two commercial species, Jinga shrimp (Metapenaeus affinis) and green tiger prawn (Penaeus semisulcatus), on the coasts of Khuzestan Province were assessed in the present study. For this purpose, regression, and RDA, as an ordination method, were employed to investigate the impacts of the depth, temperature, and salinity on the capture per unit effort (CPUE). The maximum CPUE for M. affinis in the western region (Life’h- Buseyf) was 18.75kg/h at a depth of 5m, 28.5°C and 40ppt salinity. It was obtained the 2.03kg P. semisulcatus per hour from the eastern region (Bahrkan) at 22m, 32°C, and 40ppt. The results of RDA revealed that the changes in CPUE have a statistical relationship with environmental variables. So that this relationship is direct for Penaeus semisulcatus and inverse for Metapenaeus affinis, and the sea depth was the most significant factor in fishing both shrimp/prawn species. The selection of the leading variables has also confirmed these results. Additionally, the temperature was recognized as the subsequent influencing factor, and the salinity variable had no significant effect on the CPUE of species. Regression models showed only a significant impact of depth on the CPUE of Penaeus semisulcatus, and the capture of Metapenaeus affinis lacked any statistical effectiveness of environmental variables.

The present study estimated relative frequency index of Purpleback flying squid and Oman cuttlefish also evaluated the effect of depth, distance, and time of capture (before & after noon) on them. Sampling was in the west of the Gulf of Oman at the spring of 2019. The depth of the Gulf was 208 to 285 meters. The vessel used was an industrial Myctophid trawler and the sampling gear was a rope trawl that operated with the fishing technique in a water column (the bottom panel was maximum 6 meters higher than the bottom of the Gulf). According to field observations, the average catch per unit of effort index in Purpleback flying squid and Oman cuttlefish was estimated to be 7584.22 and 1345.066 gram / hour based on weight and 19.062 and 18.250 number / hour based on number, respectively. Based on the selected models, the variables of depth and distance had a significant effect on catch per unit of effort for Purpleback flying squid (P<0.05). With increasing depth and distance, the catch per unit of effort for squid increased. However, based on the results, no significant effect of the studied variables on the relative abundance index of Oman cuttlefish was observed, given the lack of sufficient research on this theme and the discard caught of these species in Iranian waters, more extensive research to manage their stock in the Gulf of Oman is a need..

Population dynamics of Skinnycheek Lanternfish Benthosema pterotum (Alcock, 1890), in the Iranian waters of Oman Sea from April 2019 to March 2020 were studied. A total of 2893 individuals were sampled and used for analysis. Total length ranged from 21-60 mm and the average length was 39.4 mm. More than 84% of the samples were between 33-45 mm TL. The length-weight relationship was obtained TW= 0.00008 TL 2.379 and shown negative allometric growth. The asymptotic length (Loo) and growth constant (K) were estimated at 63 mm and 1.6 yr-1 respectively. Also, tmax and t0 were calculated 1/73 and -0/15 yr -1 respectively. VBGE was calculated Lt = 6.3 ( 1 – e -1.6(t+0.15)). The coefficients of total mortality (Z), instantaneous natural mortality (M), and fishing mortality (F) were estimated as 6/65 yr-1, 2/62 yr-1, and 4/03 yr -1 respectively. Size at first capture (Lc) was estimated at 35.67 mm (TL). The exploitation rate (E) was estimated as 0/60 yr -1.

This study aimed to find new species of cephalopods in the Iranian waters of the Gulf of Oman. Two species of Oegopsida (Abralia steindachneri Weindl, 1912 and Joubiniteuthis portieri (Joubin, 1916)) and also one species of Sepiida (Sepia omani Adam & Rees, 1966) were identified. Samples were collected in March and April 2019, using a Myctophidae trawler. To capture A. steindachneri a two-panel bottom trawl (codend mesh size (A) equal to 60 mm) was used, while for J. portieri and S. omani a four-panel midwater rope trawl (codend mesh size (A) equal to 90 mm) was applied. Taxonomic studied on these rare cephalopods, in this region, would be helpful for protecting their stocks as well as safely exploitation them.

Regarding to the role of law awareness in social discipline, awareness of fisheries rules and regulations will be crucial in advancing fisheries affairs. Research with study personnel awareness central headquarter central fisheries organization of Iran of the fisheries rules could measure level of awareness and their teachings in adhere direction implementation of under sector laws. 

With use of questionnaire, was collected personnel information about law provisions and executive regulations rule on the protection and utilization of the Islamic Republic of Iran aquatic resources and also their corrective opinions were collected and the scoring method was used in statistical analysis. 

 The results showed an average score of 13.8 and a score of 72.7% of the total score at a rate of 33/5% were aware of the rules and regulations of fisheries. Despite 53.8% of the generalities awareness of the rules, awareness of the more specialized rules of fishing and aquaculture was less than expectation. They were about 95% and %77 of the votes that the rules and regulations of the fisheries believed did not need to be reviewed and revised and they did believe to there was a conflict among the tasks of fisheries and other organizations, respectively. Managerial problems, planning, policy making and structural were identified as one of the most important problems in the fisheries sector. 

So despite a little awareness about of the rules, in addition to the need for review and elimination of contradictions and legal interactions the training of the rules should be more serious until sovereignty and rules enforcing can create more sustainable activities in the field of fisheries.

This study was conducted to survey of distribution and abundance of cutlassfish (Trichiurus lepturus, Linnaeus 1758) as target species between the fishing grounds of Bushehr and Hormozgan provinces. Sampling operations were carried out during the summer season in Bushehr province and autumn season in Hormozgan province in 2013. The fishing operation was done using commercial trawler vessel with a length of 27 m, the width of 7.2 m during 73 times net hauling in the fishing seasons. The used net in this research was a mid-water trawl net with a polyethylene yarn and mesh size of 75 mm (stretched) in the codend. The highest length frequency of cutlassfish was observed in the length range of 84-92 cm and the least length frequency was in the length range of 28-36 cm. The biomass and mean CPUA in Bushehr were 17169.55 tons and 8624.42 ± 1076.58 (kg nm-2) and in Hormozgan were 7425.804 tons and 8105.74 ± 1529.87 (kg nm-2), respectively. Also based on depicted maps by GIS software and CPUA index, Most densities of trapped cutlassfish in Hormozgan fishing grounds were around Hengam and Greater Tomb islands, and in Bushehr (Motaf area), there was a horizontal distribution in the western waters of this province.

To study the growth parameters of long fin banner fish, Heniochus acuminatus, samples were monthly collected from the trawl catches of five major fish landing centers (Pondicherry, Cuddalore, Parangipettai, Karaikkal, and Nagapattinam) of the southeast coast of India during January to December 2015. A total of 475 longfin bannerfish (222 males and 253 females), ranging in size from 6.0-15.2cm for males and 5.6-15.7cm for females were collected. The total body weight of male and female were ranged from 11.06-25.34g and 10.90-27.15g, respectively. The b-value estimated for male (3.006) was greater than 3 (isometric) and for female (2.809) was less than 3 (slightly negative allometric). The correlation coefficient values (r) for male (0.984) and for female (0.995) was highly significant, with a high degree of the positive correlation between total body length and weight. The relative condition factor (Kn) values were found higher in females than males during various seasons. The asymptotic length Lα values obtained using various methods for females ranged from 16.8 to 18.3cm (TL) and similarly, for males, it ranged from 16.77 and 176.4cm (TL). Most appropriate values of growth rate (K) for males and females were 1.20 yr-1 and 1.80 yr-1 , respectively. The estimated t0 for males and females were -0.191 and - 0.166, respectively. The growth parameters obtained during the present study will be used for stock assessment of this species.

Sepia pharaonis and Trichiurus lepturus are two species target catch of Bottom Trawl. These two species because of the value of export and money are very important economically. This study Biomass and the mean Catch per Unit of Area (CPUA) Sepia pharaonis and Trichiurus lepturus of Bottom Trawl fisheryfrom Oman Sea (Sistan and Balochestan province coastal waters) were investigated. Data were collected in one research cruise by using R/V Ferdows-1 during September and October 2016. The study area was stratified into 5 strata (M to Q) and 4 Substratum covering the depths of 10-20, 20-30, 30-50 and 50-100 m in the Oman Sea. A total of 92 stations were randomly selected and the biomass and CPUA were estimated by swept area method. Result indicated that maximum and minimum the mean CPUA of Sepia pharaonis was 894.0 Kg.nm-2 and 64.1 Kg.nm-2 in the region M and Q respectively. Maximum and minimum the mean CPUA of Trichiurus lepturus was 2485.3 Kg.nm-2 and 49.9 Kg.nm-2 in the region N and Q respectively. Maximum and minimum biomass of Sepia pharaonis was estimated 240.3 tons and 46.6 ton in the region P and Q respectively. Maximum and minimum biomass of Trichiurus lepturus was estimated 899.3 ton and 21.7 tons in the region N and M respectively. Also maximum and minimum the mean CPUA and biomass of Sepia pharaonis and Trichiurus lepturus were obtained in depth of 50-100 m and 10-20 m respectively. Result this study is useful for management of these two species resources from of Oman Sea.

To understand selectivity of trawl, a study was done in fishing ground of Chabahar, Konarak and Pozm by cover cod method in April 2016. 1876 fish including 23 species belonging to 15 families were caught and identified from sampling places among which Cutlassfish (Trichiurus lepturus) with 63% the largest number and Epinephelus areolatus, Torpedo sinuspersici, Epinephelus coioides, Pristipomoides multidens and Netuma thalassina with 0.05 % the lowest number to be included. Catch per unite effort (CPUE) was measured between 161.2 to 637 kg/h but its average measured as 289.98 kg/h. L50 for Trichiurus lepturus 28.18 cm, for Pomadasys stridens 11.19 cm and for Nemipterus japonicus 12.44 cm measured. Results show T. lepturus caught at the age of maturity. But P. stridens and N. japonicus caught in length much lower than maturity length. In this sense the trawl is not selective and there is a threat to fish stocks in the region.

Biomass, Catch per Unit of Area (CPUA), distribution and catch composition of Bottom Trawl demersal resources from Oman Sea (Sistan and Balochestan province coastal waters) were investigated in this study. Data were collected in one research cruise by using R/V Ferdows-1 during 2016. The study area was stratified into 5 strata (M to Q) and 4 Substratum covering the depths of 10- 20, 20-30, 30-50 and 50-100 m in the Oman Sea. A total of 92 stations were selected in a random stratified design distributed in different depths and area. The swept are method was used to access and estimate the amount of biomass and CPUA. Result indicated that the percentage of density of demersal resources in the M Stratum (Biahi to Galak estuary) and Stratum Q (Bersi to Gwatr) had the highest value of biomass and CPUA. Also depths of 10-20 m had lowest value CPUA and biomass of commercial, non-commercial and total species. The amount of biomass in depth of 50-100 m was 4.1 times higher than that of depth 10-20m. Maximum CPUA of commercial, non-commercial and total species was estimated in strata M, M and Q and M respectively. Aroun100 species were identified in this study; the results of the study suggest that high density of commercial species distribution concentrated in West-coast, while non-commercial resources observed in East coast of Sistan and Balochestan province. The Result of this study is beneficial for objective management of Demersal Resources exploitation in Oman Sea.

In order to determine the catch composition of trawl in Chabahar region (Sistan and Baluchistan coastlines), the present study was carried out in Chabahar, Konarak and Pozm ports in June 2016. 23 species belonging to 15 families were caught and identified after seven times trawling. Mean while, the maximum composition catch (63%) was observed in Cutlass fish (Trichiurus lepturus). This is while, the minimum composition catch (0.05%) belonged to Areolate Grouper (Epinephelus areolatus), Gulf torpedo (Torpedo sinuspersici), Orange-spotted grouper (Epinephelus coioides), Gold bandedjob fish (Pristipomoides multidens) and Giant catfish (Netuma thalassina). The maximumlength-frequency of Cutlass fishwas observed in the length class of 77.5 – 88.5 cm. Based on the biodiversity and indices analysis regarding the caught fish, Simpson and Shannon indices were estimated as 0.692 and 2.459, respectively. In addition, natural richness was 29.9 and evenness was calculated as 0.185 using Camargo equation.

In this study, we used "Ferdows 1" research vessel and sampling conducted on random basis, through 119 sampling stations in 7 zones with 4 deep-sea layers as: 10-20, 20-30, 30-50 and 50-100 meters, throughout the Oman Sea. Achieved data recorded in pre-schemed forms and processed through "Excel" and "Arc View GIS" soft wares. One hundred species or genus identified in bottom trawl catch composition which categorized as commercial and non-commercial species. The total biomass of aquatics in bottom trawl net estimated as 52472.7 Mt. 60% of this amount allocated to commercial demersal species with 31651.7 Mt. Comparing biomass rates in the Oman Sea layers, it is determined that the maximum biomass rate is in 50-100 and 10-20 meter layers, respectively. Study of CPUA in 7 zones of the Oman Sea revealed that identical to biomass, zone F (Sirik to Jask) positioned first with 20162 Kg per square nautical mile. For 10-20 meter layer, CPUA is 1.6 folded in 50-100 meter depth.