جستجوی مقالات مرتبط با کلیدواژه « Fishing » در نشریات گروه « شیلات »

The covid-19 disease caused millions of people in the world to face a food supply crisis. This research was planned and implemented to investigate the impact of the spread of this disease on the fisheries activities of Iran as one of the branches of food supply. The operation of collecting research data through (1) designing general and specific questionnaires, distributing them throughout the country and completing them by fisheries activists in the areas of shrimp farming, coldwater and warmwater, fishing communities, and seafood processing centers of different provinces, (2) gathering information, directives, and necessary data such as the production statistics of the Iranian Fisheries Organization, and (3) a review of the research and actions carried out in other countries. The average reliability of 1044 completed questionnaires was determined as 0.81 based on Cronbach's alpha. The results showed that during the outbreak of the disease, providing inputs and raw materials for growers and processing factories was more difficult (with an average of 65±3%) and more expensive (with an average of 56±5%). The domestic and international restrictions imposed during the quarantine period can be considered as one of the main factors for the difficulty in providing raw materials. In this context, 79% of these people believed that the transportation of raw materials was more difficult these days and affected the supply of the product. The decrease in demand and the increase in the cost of production increased the amount of storage of the manufactured product, which increased the risk and cost for the producers. 70% of the respondents have observed and announced the concern about disease transmission by fish and the decrease in demand among consumers. In the field of employment and economy, the increase in the cost price of the produced product was observed to a higher extent in aquaculture sectors and seafood processing factories. Instead, the fishing community reported the highest rate of job loss among the research target groups. 80% of the production sectors announced that their income decreased during the outbreak of the disease. Also, the results of this research showed the reduction of workers and employees of the production sectors in all groups during the outbreak of the disease. In general, about 78% of the audience announced that the fisheries activities of the country were affected by the negative effects of the coronavirus disease. According to these results and the short-term impact of this disease, among the strategies to deal with crises, the strategy of endurance for similar crises is proposed. To increase the resistance of the country's fisheries sectors in similar cases in the future, solutions and measurements have been proposed such as classifying fisheries activities as vulnerable businesses, developing assistance programs and emergency operational packages, implementing promotion and information measures, regional management in the provinces to meet the needs of the markets, extending, automatic renewal of farm exploitation licenses, the strengthening and development of cold storage plants and processing factories, the necessity of immediate support for local fishermen, and the expansion of online methods of selling aquatic products.

This study aimed to investigate the changes and growth pattern of Beluga sturgeon fishing in fishing regions of Golestan and biological characteristics of this species over a period of 13 years. The highest amount of Beluga sturgeon fishing was in 2008, when a total of 95 pieces of this species were caught from five fishing grounds in Golestan province, and the lowest amount was caught in 2020, when 3 pieces of this species were caught. The results showed that the highest average total length was observed in 2020 and the highest total weight was observed in 2017 and the lowest average total length and total weight was obtained in 2011.The sex ratio of male to female elephant fish in the thirteen-year period was 0.66:1, which was significantly higher than the female population (X2=19.69, p<0.05). The range of growth coefficient (b) for the population of Beluga sturgeon between 2008 to 2020 years varied from 2.56 to 3.97. The results of Pauli test for the relationship between length and weight of Beluga sturgeon species showed that the growth pattern of this species in 2008 and 2010 were negative allometric, in 1393, 1396 and 1397 positive allometric and in 2009, 2011, 2012, 2013, 2015, 2016, 2019 and 2020 were isometric. In general, in a period of 13 years, the amount of elephant fishing in the coasts of Golestan province decreased by more than 90%, so in this region, this trend for Beluga sturgeon is among the most endangered species, concluding an alarm for conservation of this valuable species in Caspian Sea..

This study aimed to investigate the changes and growth pattern of Persian sturgeon fishing in fishing regions of Golestan and biological characteristics of this species over a period of 10 years. The highest amount of Persian sturgeon fishing was in 2012, when a total of 143 pieces of this species were caught from five fishing grounds in Golestan province, and the lowest amount was caught in 1398, when 49 pieces of this species were caught. in the present study, the maximum total length of Qarabrun was in 1397 with a total length of 257 cm. Mianqaleh fishing farm had the highest number of catches (471 pieces) of this species and the lowest amount of catches (26 pieces) for this species was recorded in Chalasht fishing farm. The results showed that the highest average total length was observed in 2014 and the highest total weight was observed in 2017 and the lowest average total length and total weight was obtained in 2012. The sex ratio of males to females of Persian sturgeon species in the ten-year period was 1.24: 1, where the male population was higher (p < 0.05). The range of growth coefficient (b) for the population of Persian sturgeon in the years 2011 to 2020 varied between 2.60 to 3.82, The results of Pauli test for the relationship between length and weight of Persian sturgeon species showed that the growth pattern of this species in 2011 and 2012 was negative allometric, in 2015 positive allometric and in 2013, 2014,  2016, 2017, 2018, 2019 and 2020 It was isometric. Conclusion of this study shows that in a period of 10 years for Qarahbrun species had a decrease of 75%, so in the waters of Golestan province this trend for Qarahbrun is among the most endangered species and this means an alarm for this valuable species It has been heard in the Caspian Sea.

In the present study, the fishing status and production of caviar from wild sturgeon as well as the stocks rehabilitation of these species in the Caspian Sea have been analyzed over the past few years. Unfortunately, due to certain reasons such as overfishing and poaching, destruction of spawning areas and natural habitats, environmental pollution and reduced the number of released juveniles sturgeon, the generation of these valuable species has sharply declined and the catching amount reached only to 13 tons in south parts of the Caspian Sea in 2019. With this situation, it seems that through the upcoming years, the generation of some fishes from the Caspian Sea will become rare and extinct. Meanwhile, attention to aquaculture of these fish, especially beluga and Siberian sturgeon has increased in Iran, so that the amount of meat and caviar production in 2019 was 2830 and 10. 6 tons, respectively. Given the severe decline in the sturgeon stocks, the necessity of rehabilitation of natural spawning areas in the rivers, prevent poaching and continuing stocks rehabilitation under the management of all surrounded countries should be considered in form of a proper "action plan" for the Caspian Sea. Moreover, for more awareness of the public people and the appropriate cultural issues, a certain day is suggested as "National Sturgeon Conservation Day".

Iran has many potential and opportunities for the development of aquaculture with the goal of producing and diversifying food, improving food security, non-oil exports, foreign exchange, and most importantly, generating productive employment directly and indirectly. The aim of this study was to analyze the performance of the northern and southern provinces in the fisheries sector. Instruments and Methods: In this descriptive study, provinces including Bushehr, Khuzestan, Sistan and Baluchestan, Golestan, Guilan, Mazandaran, and Hormozgan were examined by Multi-Attribute Decision Making (MADM) and, in particular, the prioritization technique based on the technique for order of preference by similarity to ideal solution (TOPSIS). The data were collected, using the 2015 Statistical Yearbook of Fisheries Organization and the Statistical Yearbook of Iran. Multi-attribute decision making (MADM) was used to analyze the data. Findings: Based on the statistics used and the selected indices, Mazandaran had the best performance in the fisheries sector among the provinces. Guilan, Hormozgan, Khuzestan, Sistan and Baluchestan, Bushehr, and Golestan provinces were in the next ranks. In the fisheries sector, Mazandaran province has the best performance among the provinces of Guilan, Hormozgan, Khuzestan, Sistan and Baluchestan, Bushehr, and Golestan.

Nowadays, the management of water resources by planning through appropriate site selection, fish species storage and selection, enforcement and providing various side services has become a profitable, entrepreneurial and fun process. Survey and usage of development of fee-fishing experience in the world wide represent a model in order to a better economical and fun plan offers and environmentally compatible. In addition to paying attention to the environment, its economic aspect will also be considered, as well. Water management is the only one part of management process alongside of human resource management, insurance benefits, selling license and equipments, training, employment, security and peace in the country that requires special attention. Iran In addition of catching over 38000 tons of fish from inland water resources, also has abundant of water resources planning and management for sports fishing This article presents offers to improve the performance of fee-fishing activities by reviewing evidence about the operation of water resources investment and development in Iran.

Age and growth of the king soldier bream, Argyrops spinifer (Forsskal 1775) in the Persian Gulf (Bushehr coasts) were investigated. A total of 622 samples were obtained from June 2010 to May 2011. Total length (TL) of fish ranged from 13.5 to 64.2cm (females) and 15 to 61.2cm (males). Male and female fish age ranged between 2+ to 25+ and 2+ to 21+ years, respectively. Values of the von Bertalanffy growth function were calculated in females, males and total population by using the backcalculation method and otolith reading data. The values of these parameters according to otolith reading data were K=0.061, L∞=82.10cm (TL), t0=- 2.39 years for females and K=0.082, L∞=67.90cm (TL), t0= - 2.88 for males and K=0.065, L∞=75.50cm (TL), t0=-3.21 for total population and according to backcalculation method were K=0.088, L∞=76.37cm (TL), t0=-0.329 years for females and K=0.101, L∞=65.71cm (TL), t0=-0.168 for males and K=0.094, L∞=74.55cm (TL), t0=-0.191 for total population. The results of the study provide the direction for the future management models for the continued sustainable exploitation of this species in the Persian Gulf region.

This study was carried out in Turkmen fishing station to examine suitable mesh size of gill nets for Persian sturgeon, Acipenser persicus, to decrease possibility of catching immature specimens and increase catch likelihood for larger fish. The Holt model was used to determine suitable length for catch and selection of mature Persian sturgeon females. Following preliminary studies some 920 experimental gill nets (mesh size 170mm) similar to those generally used by Iranian Fisheries except for mesh size (150mm) were set up in the Caspian Sea. During the experimental period, 128 and 110 sturgeons were caught in control and experimental nets, respectively. Out of those caught in control nets, 63 specimens were Persian sturgeon (49.2%), 57 were Stellate sturgeon, Acipenser stellatus (44.5%) while in the experimental nets, 95 specimens (86.4%) were Persian sturgeon and 7 specimens (6.4%) were Stellate sturgeon. Regarding maturity status of fishes, 42 Persian sturgeon caught in control nets were mature females while this figure was 83 (87.4%) in experimental nets. Mean fork length of the Persian sturgeon was 152.9±13.8cm and 162.4±13.6cm in control and experimental nets, respectively. The mean caviar yield of the Persian sturgeon in control nets was 6.4±1.7 kg and in experimental nets was 7.4±1.9kg. One way ANOVA and Tukey’s test showed significant differences between factors like age, mean caviar yield and fork length of the Persian sturgeon caught in control and experimental nets. The results showed increasing mesh size of gill nets to 170mm for the Persian sturgeon may help achieving objectives of stock managements including decrease in catch of immature fish and increase in catch of mature and larger sturgeons which can secure optimum and sustainable stock yield.

Non-commercial fish species of shrimp trawls were studied monthly from October 2005 to September 2006 in Mahshahr creeks (Darvish, Doragh, Bihad, Ghazaleh, Ghanam, Zangi and Patil). The trawl nets had a cod-end mesh size of 24mm. Total catch was 6431 individuals weighing 55.5kg, and included 14 species of non-commercial fish species belonging to 14 families. The caught shrimp species were from Penaeidae; comprising only 30% of the total catches (4506 individuals weighting 44kg). Dominant species were Lieognathus hindus (54.8%), Metapenaeus affinis (18.2%) and Parapenaeopsis stylifera (9.8%). Maximum fish abundance was observed in March 2005 (98/3%) and for shrimp in June (66.2%). Bihad creek had the maximum percentage of fish (91.8%) by-catch and shrimp (42.9%) abundance. We conclude that the by-catch percentage of non-commercial fish is higher than shrimps in the study areas. Warm months witnessed the highest abundance of shrimp while January-March was the time period when by-catch was most abundant.

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° 30' N" and 51° 30' E) to Daylam waters (30° 00' N and 50° 00' E) the northern part of the Iranian waters of the Persian Gulf. Assessment was conducted using 45 stations on 15 transects in water depths less than lOrn, 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 found 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 hows 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.