Azar Bagheri, Mahnazsaddat Sadeghi, Behnam Daghooghi ,
Volume 5, Issue 2 (7-2013)
Abstract
Feeding biology of Indian mackerel (Rastrelligerkanagurta) was investigated from autumn 2011 to summer 2012 in the northern waters of Persian Gulf (Hormozgan Province waters). Random samples of this species were collected seasonally. Stomach contents analysis of 180 samples indicated that the planktons were main food of this species (93%) and followed by random food included (fish 7%)Zooplanktons were more than%55 (phytoplankton 45%). The main zooplanktons were crustacea (81%) and mollusks(10%). Copepod were dominant (71%) in crustacea. Among phytoplankton Bacillariophyceae were the main food(79%) which followed by Dynophyceae (20%) and Cyanophycea (%1).Engraulissp. (7%) was the only fish that found in stomach contents. Stomach emptiness index (CV) and FullnessIndex (FI) for this species were calculated 36.1 and 29.44, respectively. Maximum and minimum of GSI were calculated 2.15 and 1.12 in autumn and winter, respectively. Condition factor (CF) and the relative length of the gut (RLG) were calculated 1769.97 and 2.39, respectively, during the study period.
, , ,
Volume 9, Issue 1 (6-2017)
Abstract
Pollution is one of the most important issued problems in protection of marine areas and saving their ecological balance. Although contaminants remain for a long time in sediments, but their biological activities and also variation of physical and chemical conditions can shift them to upper waters. Heavy metals especially mercury due to their toxicity and persistence in the environment are important in terms of public health. In order to determine the mercury and methylmecury levels in sediment of Hormozgan Province, 51 surface sediment samples were sampled from 6 transects (in 3 depths) located at Strait of Hormoz, Larak Island, Faror Island, Qeshm Island, around Tonb e Bozorg and Lavan Island in January 2008. After preparation and acid digestion, samples were analyzed using Cold Vapor Atomic Absorption Spectrometry. The results of this study demonstrated that accumulation of mercury in the sediments of deeper parts around Larak and Faror Islands was more than other stations and depths. Minimum and maximum mercury levels in the sediments of Hormozgan province were belonged to the sediments of 24 meters in arrounds of Lavan Island and to the sediments in the depth of 94 meters at the strait of Hormoz as 12 and 55ng/g d.w., respectively. The range of methylmercury was varied from 0.9 at the depth of 59 meters of Larak Island to 0.41 ng/g d.w. at the depth of 85 meters of Lavan Island. The maximum total mercury level in the sediments of Lavan Island (consisting of 3 depths) was 43ng/g d.w., which was almost 70% more than median mecury level in the sediments of Ton e Bozorg Island (29.3 ng/g d.w).
Mousa Keshavarz , Maryam Soyufjahromi , Abdul- Reza Dabbagh,
Volume 12, Issue 3 (10-2020)
Abstract
Moshta (Hadrah in Arabic language) is an intertidal fixed stake trap which is one of the oldest types of fishing gear in the countries of the Persian Gulf including the southern coast of Iran. The detailed data on the mass caught by Moshta in terms of species and quantity (tons/year) in periods of 2007-2010 and 2013-2017 of Hormozgan Province were collected from the Iranian fisheries organization (“Shilat” in Iran) and analyzed in Excel to indicate the amount of catch and the commercial status of aquatic landings. In Iran, Moshtas are only found in the southern provinces. In Hormozgan Province, they are used for earning a livelihood. Many commercial species including demersal and pelagic fishes, shrimp and crabs, are caught by this fishing gear. Moreover, some aquatic animals such as sea turtles and sea snakes may be entangled as by-catch. Results showed that over 34 species of aquatic organisms can be caught by set net (Moshta) in Hormozgan Province coastal area. Analysis of catch composition shows that in Hormozgan province, bony fish with 59.66% have a major share in the composition of fishery. Then, cartilaginous fish with 20.41% and crustaceans with 18.90% are at the next level and in finally, cephalopods have the least share (1.02%). In addition, Himantura sp. (10.76%), Himantura sp. (49.67%), Metapenaeus affinis & Fenneropenaeus merguiensis (18.90%), Portunus pelagicus (16.32%), Arius sp. (18.15%), Liza klunzingeri (10.43%), Pseudorhombus arsius (16.13%), Portunus pelagicus (13.04%), Metapenaeus affinis & Fenneropenaeus merguiensis (15.25%) were the dominant species of Moshta in 2007, 2008, 2009, 2010, 2013, 2014, 2015, 2016 and 2017, respectively. Furthermore, results clearly illustrate reduced fishing during the second period of catch, 2013-2017, (by the average of 410.2 tons per year) in comparison with the first period (2007-2010, with the average of 1053.5 tons per year).
Farshid Mirzaei Sadr, Hadi Raeisi2, Mohammad Harsij, Sarah Haghparast, Hojatolah Jafariyan, Ziya Kordjazi, Mohammad Hasan Gerami5,
Volume 14, Issue 1 (4-2022)
Abstract
This study was conducted to estimate length-weight parameters of obtuse barracuda (Sphyraena obtusata) in fishing grounds of the Persian Gulf and Oman Sea (Hormozgan province) during 18 months from September 2019 to February 2021. Sampling was done using mid-water trawlers, Goshgir and Moshta nets. Totally, 443 samples including 206 males and 237 females were subjected to biometric measurements and sex determination. Mean length of male, female and the whole population of obtuse barracuda were 22.61±2.97 cm, 22.57±2.8 cm and 22.48±3.11 cm, respectively. Using least square method for fitting, length-weight relationship for male was W=0.004×L3.16, for female was W=0.004×L3.208, and for the whole population was W=0.004×L3.189. Considering the growth models tested here, parameters of L∞, k, t0 were 30.25 cm, 0.587 year-1and -0.257 for male, respectively ,males, 32.1 cm, -0.46 year-1, -0.349 for female respectively and 59.17 cm, 0.195 year-1, -0.726 and 4.65 cm respectively for the whole population. A logistic relationship was found between fish weight and fish age. The infinite weights of male, female and the whole population of obtuse barracuda were estimated 295.02 g, 241.23 g and 326.2 g, respectively. Total mortality was obtained 1.562 year-1 for male, 1.006 year-1 for female and 1.332 year-1 for the whole population. Exploitation rate was estimated 60% for male, 51 % for female and 54% for the whole population. The present results indicate a pressure on obtuse barracuda stock and if it is continuing, the fish stocks will be drastically declined in near future.
