Showing 17 results for Oman Sea
Mohsen Dehghani, Ehsan Kamrani, Ali Salarpouri, Eisa Kamali,
Volume 2, Issue 1 (6-2012)
Abstract
Correlation between fish length, length and weight of otolith of sardine in the Southern waters of Iran still unknown. Therefore, because of commercial and ecological importance of Sardinella sindensis, relationships between fish length (total length), length and weight otolith was studied. In total, 123 Sind sardine were sampled by double –boat purse seiners from coastal waters of Jask from October 2010 to September 2011. Minimum and Maximum of length and weight of fishes were 7.8-19.19 cm and 4.63-59.11 g, respectively. Length and weight of otoliths were 1680.13-3339.45 mm and 0.0005-0.00261 g, respectively. Using t-test, no significantly differences were observed between left and right otolith (P>0.05). The results showed that there was relatively high correlation coefficient between fish length and otolith length (TL= 132.26 OL+ 730.17, r2=0.76), also between fish length and otolith weight (OW=0.00002TL1.6852 ,r2=0.75). For comparison between hypothetical (b) and calculated (b) in this study, t-test carried out, and result showed that the growth of fish and otolith is isometric (P>0.05).
Arash Shakori, Gilan Attaran Fariman, Mona Askari Nasab,
Volume 4, Issue 3 (1-2015)
Abstract
Polychaete worms with high species richness and diversity play a key role in the water food chain. In this research polychates of the intertidal zone of Tis coast in Chabahar bay were studied. Sampling was conducted over a period of one year, from summer to winter 2013 and during four seasons by 50 cm×50 cm quadrats. Twenty two families and 30 genera and 4 species were identified polychaetes.The dominant species of polychaetes were identified: Prionospio sp., Nepthys spp., Scoloplos spp., Spio sp., Ophelia sp., Aphelochaeta sp., Armandia leptocirris. Polychaetes were the most common in winter with 305 Ind.m and autumn with 89 Ind.m is the minimum frequency. Statistical analysis by two-way ANOVA showed significant differences (P>0.05) between the abundance of polychaetes in the year seasons. The species diversity and richness with values 3.6 and 0.88 in winter and the level of environmental integrity in the spring and autumn with value 0.63 and 3.11, respectively, were the highest dominance. The third station with mean 3.29 in four seasons had the highest Shannon index, which reflects the greater diversity of polychaetes in this station. The results showed that this area is very rich in terms of density and diversity of polychaetes. The result obtained from this study could examine the status of contamination by comparing records.
Marzieh Razzaghi, Sakineh Mashjoor, Ehsan Kamrani,
Volume 6, Issue 1 (7-2016)
Abstract
We examined the temporal trend in mean trophic level (mTL), trophic category landing (TrC) and landing profile (LP) of the exploited marine community (49 species) in the fishing zone of Hormozgan (north of Persian Gulf and Oman Sea) from 2001 to 2011. LP had an increasing trend (r = 0.88, P<0.001), whereas, mTL of the landings showed a significant decrease from 2001 to 2011 (r = -0.69, P<0.05). We observed a decreasing trend in the landing of carnivores and predators of the upper level food web during the study period, which could be a sign for the phenomenon of fishing down marine food web in the water bodies of Hormozgan Province. The results of cluster analysis and nonmetric dimentional scale divided the composition and amount of landings into two year groups (2001–2007 and 2008–2011). Analysis of similarity revealed a significant difference between these two year groups (r=0.88; P=0.005). Benthosema pterotum and Thunnus albacores were responsible for this dissimilarity in composition and amount of these two groups.
Mohsen Safaie, Mozhgan Shariat,
Volume 6, Issue 2 (10-2016)
Abstract
Feeding habits of the blue swimming crab, Portunus segnis were studied in the coastal waters of Chabahar (Oman Sea) during the period from January 2015 to June 2015. The stomach contents of 623 crabs (included 138 males and 125 females) were analyzed. Their contents appeared to consist of mainly large quantities fish (48.2 %), crustaceans (19 %) and molluscs (15.7 %), also small quantities of seagrass (3.3 %), mixed matter (8.8 %), unidentifiable matter (5 %) and debris. The C.V. index was 44.8 %, also the crabs in the warm season most voracious (CV=38.9 %) than in cold season (CV=51.1 %). The crabs without barnacle comparatively voracious with barnacle-carrying crabs (p<0.05). There was no difference observed in the quantity of the food consumed in both sexes and also significant differences observed in the preference for food items in the different size groups. Based on the major food items were observed in different size groups, the crustaceans, fish, and molluscs were the most dominant in juvenile crabs and the fish items were the most dominant (with 62 %) in adult and larger size groups crabs.
Seyed Abbas Hosseini, Mohammad Darvishi, Gholamreza Drayanabard,
Volume 6, Issue 3 (4-2016)
Abstract
Diet of kingfish was examined in the Iranian coastal waters in the Persian Gulf and Oman Sea during the year 2005-08. With the examination of 1655 kingfish stomachs caught by drifting gillnets, it was revealed that this species fed three groups of preys including fish, Cephalopods, and Crustaceans, of which the fish group accounted for the highest in the frequency of number (99.3%) and in the frequency of occurrence (99.1%). Nine families for the fish group, one family for Cephalopods and one family of Crustaceans were identified, with totally fifteen species were identifiable. In fish group, Engraulididae and Clupeidae families had the highest frequency of number (22% and 13.5% in respective family) and the highest frequency of occurrence (8.4% and 14.4% of the total stomachs examined in respective family), which Clupeidae seems to be a preferred food for kingfish in the coastal waters. Feeding intensity of kingfish is higher when the peaks of small pelagic catches occurred in spring and winter in the coastal waters. Because of the importance of Sardines and Anchovies in the feeding of kingfish, it is necessary to harvest the valuable resource of the small pelagic fish.
Mehran Parsa, Ehsan Kamrani, Mohsen Safaei, Seyed Yusef Paighambari, Tom Nishida,
Volume 7, Issue 2 (10-2017)
Abstract
Length frequency, length-weight relationship and catch per unit of effort (CPUE) for longtail tuna and yellowfin tuna in purse seine fishing were studied in Oman Sea between July and August 2015. Length range and mean of longtail tuna were obtained 56-98 and 74.13±0.41 cm, respectively. Length range and mean of yellowfin tuna were obtained 51-128 and 74.62±0.46 cm, respectively. The length-weight relationship of longtail tuna and yellowfin tuna were calculated as W = 0.0174L2.9142 and W = 0.0655L2.7934, respectively. Totally, 802 tonnes of longtail tuna and yellowfin tuna were caught including 220 tonnes (27.43%) longtail tuna and 582 tonnes (72.57%) yellowfin tuna. Mean of CPUE (± S.E) was obtained 21.98±1.61 tonnes/setting for longtail tuna and 32.65±2.63 tonnes/setting for yellowfin tuna. Minimum and maximum CPUE of longtail tuna were calculated 7 tonnes/setting and 35 tonnes/setting, respectively. Minimum and maximum CPUE of yellowfin tuna were calculated 5 tonnes/setting and 150 tonnes/setting, respectively. Results indicated that about 31% of caught longtail tuna and 39% of caught yellowfin tuna were immature and had no opportunity to spawn. Continuation of this exploitation process can lead to recruitment overfishing of these two species.
Ali Reza Rastgoo, Tooraj Valinassab,
Volume 7, Issue 2 (10-2017)
Abstract
In this study, trophic interactions were studied among three elasmobranches including Iago omanensis, Rhinobatos punctifer and Torpedo sinuspersici coexisting in the depth ranging from 50 to 100 meters in the Oman Sea (Sistan and Balochistan waters). A total of 238 specimens were collected using industrial bottom trawlers of ‘FERDOWS’ during spring and summer,2014 and their stomach contents were analyzed based on VI, FO, %IRI indices and nMDS analysis. Results showed that I. omanensis fed mainly on teleosts, and crustacean and cephalopod were found in the several stomachs. Moreover, T. sinuspersici had specialized diets on teleosts. On the other hand, R. punctifer had a specialized diet on crustacean. An analysis of similarity showed significant differences among three studied species (R=0.574; P=0.001). Analysis of pair-wise tests detected the greatest dietary differences between R. punctifer and T. sinuspersici, while I. omanensis and T. sinuspersici showed the lowest differences. The results showed that there is resource partitioning, which can be related to morphology and feeding behavior of each species.
Mr Moslem Sharifinia, Mohammadreza Taherizadeh, Dr Javid Imanpour Namin, Dr Ehsan Kamrani,
Volume 7, Issue 4 (4-2018)
Abstract
This study aimed to assess the ecological status of Khamir, Tiyab and Jagin creeks and the impact of human activities on the studied ecosystems using AMBI biological indicator. During the study period, 165 macro-benthos taxa belong to seven phyla including Annelids (65 taxa), Mollusca (65 taxa), Arthropods (28 taxa), Echinoderms (3 taxa), Hydrozoans (2 taxa), Nemertea (1 taxon) and Nematoda (1 taxon) were identified. For the total abundance, Polychaeta showed the richest taxonomic feature with 62 species, contributed 37.57% of the total abundance. The average values of AMBI in the four seasons ranged from 1.12±0.09 (spring) to 5.08±0.15 (autumn). The highest values occurred at station 6 (spring, 4.12±0.81; summer, 5.01±0.56; autumn, 5.08±0.15; winter, 4.42±0.38), and the lowest values occurred at stations 7 (spring, 1.12±0.09; summer, 1.24±0.07), and 1 (autumn, 1.25±0.07; winter, 1.33±0.24). Results from ecological status of studied creeks using AMBI index throughout the year showed that Khamir creek classified as "slightly polluted" to "moderately polluted", Tiyab creek classified as "slightly polluted" to "heavily polluted" and Jagin creek classified as "slightly polluted". The findings of this study revealed that the AMBI index is suitable for separation of areas with less impacted by human activities from areas affected by these activities and could be used as a robust management tool for monitoring programs.
Gilan Attaran Fariman , Nasrin Panahloo , Fariborz Soheili ,
Volume 8, Issue 1 (7-2018)
Abstract
In this study, sea stars Aquilonastra watersi and Patiriella paradoxa were collected from the rocky intertidal area in Tis Port on the western coast.and the rocky shallows depths of 7-8m at Konarak on the Iranian eastern coast of Chabahar Bay, respectively in November 2014. Specimens were collected in plastic sampling boxes containing seawater and transferred to the laboratory of Chabahar Maritime University. The specimens were morphologically assessed. Then in order to examine gene sequences, DNA was extracted by CTAB method and after performing PCR, mitochondrial 16S rRNA gene was sequenced. The phylogenetic-trees for these species were drawn by Maximum Likelihood methods. The evaluations of results showed that despite differences in morphology, A. watersi is sister group of Aquilonastra. Batheri. Based on the results P. paradoxa from present study andP. regularis are in a monophyletic clade, supported by high bootstrap.
Sakineh Mashjoor, Rahim Payghan, Zahra Tulaby Dezfuly, Mehrzad Mesbah,
Volume 8, Issue 3 (1-2019)
Abstract
The Persian Gulf and Oman sea fish have valuable economic species. The purpose of this study was to evaluate morphometric properties and otolith biometry of Tigertooth croaker Otholites rober in Persian Gulf and Oman sea. The otolith of 20 fish was extracted from their abdominal sections after biometry, and the otolith indices were calculated. The results of four morphometric and six meristic measurements were recorded as: body weight (394±12.7), total length (34.25±2.1), standard length (30.25±1.4), body depth (8±2.7), number of vertebrae of the spine (23-24), scales type (catenoid), number of hard rays of dorsal (27-28), anal (8), thoracic (12-14) and abdominal fins (5). The otoliths showed a sharp rostrum, blade post-rostrum, and a certain anti-rostrum. The otolith indices of size (0.035), elongation (1.89) and thickness (0.34) showed the average range and closer in shape to an oval. The linear regression showed positive correlations between the otolith length and width, the otolith length and width with weight of the fish, and between the fish length and the otolith length (p <0.05), but no significant correlation was found between otolith weight and fish weight (p >0.05).
Salim Sharifian, Bahare Shahbanpour, Ali Taheri, Moazameh Kordjazi,
Volume 8, Issue 4 (4-2019)
Abstract
Seaweeds are one of the most important resources for extraction of natural bioactive components. In the present study, effect of different solvents (methanol 100%, methanol 70%, acetone 100%, and acetone 70%) was evaluated on the phenolic components extraction and antioxidant properties of two brown seaweed species (
N. zanardinii and
P. australis) from Chabahar coasts. Antioxidant activities of the first extract and its fractions including chloroform, dichloromethane, ethyl acetate and aqueous phase were measured using total phenolic content, DPPH free radical scavenging activity, reduction power and metal chelating activity methods. Phenol content and antioxidant properties were higher in 100% methanolic extract compared to other treatments for both algae. Ethyl acetate fraction of
N. zanardinii showed the best antioxidant activities. Antioxidant properties of
N. zanardinii were considerably higher than
P. australis. The results showed that
N. zanardinii can be considered as potential sources of natural antioxidants.
Vida Maturi, Hadideh Maboodi, Tooraj Valinssab,
Volume 8, Issue 4 (4-2019)
Abstract
This research was carried out to assess the effect of depth on distribution pattern, on density, and Catch Per Unit Area (CPUA) of Nemipteridae family in Oman Sea. Sampling was carried out using Ferdose I investigative vessel by trawl floor in cape of meydani (55° 58) east to Govater (61°25׳) east in the waters of the Oman Sea (Sistan and Baluchistan) in September-October 2013 (during 25 days). The whole sampling area was divided into five regions (A, B, C, D, E), with depth layers of 10-20 m, 20-30 m, 30-50 m and 50-100 min a total 82 trawl stations. The highest biomass and CPUA of Nemipteridae were recorded in the stratum D (Kenarak,Chabahar, Ramine-Kijdof) approximately 1075.5 tons and 2002.8 kg/nm2, respectively. Moreover, the highest biomass and CPUA were observed in depth layer of 30-50 approximately 919.8 tons and 2641.9 kg/nm2, respectively. Finlay the distribution map of this family was drawn with Arc-GIS version 9.3 software. The results showed that the main habitat of this family is D station (Kenarak,Chabahar, Ramine-Kijdof) in depth 30-50 m that can be affected by several factors such as food abundance and environment factors.
Alireza Nazari Bajgan, Arash Akbarzadeh, Hasan Salehi, Ehsan Kamrani, Mehran Yasemi,
Volume 9, Issue 3 (12-2019)
Abstract
Myctophids are one of the most important and valuable resources of fish in the waters of the Oman Sea. Considering the economic aspects of its harvesting has an important role in catch management and profitability of fishing vessels. In this study, the economic profitability of different length classes of lanternfish (Benthosema pterotum) fishing vessels was investigated using Internal Rate of Return (IRR) in northwestern waters of the Oman Sea from April 2016 to March 2017. Lanternfish trawler vessels were classified in four length classes including 35-40 m (A class), 40-45 m (B class), 45-50 m (C class), and more than 50 m (D class). IRR index of vessels in each length class was calculated with consideration to the shipping costs and income of selling fish. Mean IRR (±SD) in one year and A, B, C, and D ship classes were obtained as 41±35, 55±55, 40±36, 41±28, and 35±28%, respectively. Results of this study showed that active lanternfish fishing ships have an appropriate internal rate of return and low investment risk in waters of the Oman Sea, and C ship class (45-50 m) showed the best internal rate of return and the lowest investment risk among four classes of lanternfish fishing ships. Results of this study can be used to improve the harvesting management of lanternfish resources and consequently, organize the active fishing ships in the waters of the Oman Sea.
Dr Salim Sharifian, Dr Mehran Loghmani,
Volume 13, Issue 3 (10-2023)
Abstract
Marine plants are good source of natural antioxidant compounds. Mangroves are a group of salt-tolerant marine plants of intertidal areas with numerous medicinal properties. In the present study, phytochemical analysis (steroids, alkaloids, phenols, flavonoids and tannins) and antioxidant properties (total phenolic content, DPPH free radical scavenging activity, reduction power and metal chelating activity) of methanolic extract of leaves, stem bark, and roots of mangrove species Avicennia marina was investigated. The mangrove samples were collected from the shores of Gwater Bay in the southeast of Sistan and Baluchestan province. Phytochemical analysis showed that all the tested compounds were present in the extract of mangrove leaves, except alkaloids. While in the stem bark extract, only phenolic compounds, flavonoids and tannins were observed and alkaloids and steroids were not detected. Alkaloids, phenols and flavonoids were discovered in the root extract. The assessment of the antioxidant properties showed that among different parts of mangroves, the highest amount of phenol (6.28 mg gallic acid/ g extract), free radical scavenging (59.18 %) and iron ion reduction power (absorbance at 700 nm: 0.37) was found in the leaves extract. Contrary to these two indicators, the highest amount of iron chelating activity (absorbance at 562 nm: 0.84) was found in mangrove root extract. The results of this research showed that different parts of the mangrove plant, especially its leaves, can be considered as a potential source of natural antioxidants.
Dr Siamak Behzadi, Dr Hadi Kouhkan, Dr Ali Salarpouri, Dr Mohmmad Darvishi, Dr Reza Dehghani,
Volume 13, Issue 4 (12-2023)
Abstract
Coastal areas represent the most vulnerable regions of the ocean. Thus, the identification and estimation of sedimentation rates in the sensitive coastal habitats of Qeshm and Lark islands were conducted during 2022-2023. The diving team identified three habitats consisting of natural structures in the north of Larak Island, characterized by the predominance of Acropora sp., and one habitat featuring flora and fauna originating from human-made structures (Doha Qeshm Jetty). These habitats, resembling those on Larak Island but on a smaller scale, were mapped using ArcGIS software 10.1. Three sediment traps were placed at 500-meter intervals in each station to cover each habitat comprehensively. The minimum and maximum sedimentation rates were measured at Larak Islands (St3) with 28 and Doha Qeshm Jetty with 196 (g/m2/day), respectively. Additionally, the minimum and maximum concentrations of suspended substances in the water column, ranging from 9.44 to 21.31 (mg/lit), were observed at these two stations during autumn. The freshness of Acropora sp. served as an indicator in all four habitats, potentially reflecting either the negligible impact of sedimentation rates on communities or the resilience of these communities to sedimentation during the study period
Ms Atefeh Bampoury, Dr Salim Sharifian, Dr Seraj Bita,
Volume 14, Issue 2 (8-2024)
Abstract
Fish are a significant dietary source of various minerals essential for human health. This study examined the mineral profile (sodium, potassium, calcium, magnesium, iron, zinc, copper, iodine, selenium, and chromium) and harmful trace elements (mercury, lead, cadmium, and arsenic) in different parts of the bigeye ilisha (Ilisha megaloptera), including the backbone, head, abdominal fin and viscera, caudal fin, and fillet, from the northern coast of the Oman Sea. Results revealed significant variations in element concentrations among different parts, with higher mineral levels often found in waste parts compared to the fillet. Most minerals were present in amounts exceeding human dietary requirements, suggesting that processing waste parts of bigeye ilisha could be beneficial as food or dietary supplements. Additionally, the levels of harmful elements—mercury, lead, cadmium, and arsenic—were below permissible limits for human consumption. These findings support the potential for developing value-added products from bigeye ilisha.
Dr Siamak Behzadi, Dr Ali Salarpouri, Dr Hadi Kouhkan, Dr Mohammadsedigh Mortazawi, Researcher Gholamali Akbarzadeh Chamachaei,
Volume 14, Issue 4 (2-2025)
Abstract
A promising approach for restoring fish stocks is the creation of artificial reefs (A.Rs). An important factor in site selection for these reefs is the study of Total Suspended Solids (TSS) and sedimentation rates, which offers valuable insights for the future of fish populations in the area. This study focused on three stations, with three repetitions at each, located in the eastern and western basins of the Cape of Jask, areas designated for artificial reef construction. Data was collected during the summer and winter seasons of 2023. The minimum and maximum sedimentation rates were observed at the fourth station in the eastern basin (winter 2023), with a mean of 10.98 (±0.8) g/m²/day, and at the third station in the western basin (summer 2023), with a mean of 17.34 (±0.92) g/m²/day. The average sedimentation rate in the eastern basin was 12.44 (±1.02) g/m²/day, while the western basin had a higher average of 15.77 (±0.81) g/m²/day, indicating greater sedimentation in the western basin. The highest sedimentation rate in the eastern basin was measured at station 5 during the summer of 2023 (76.4%), and the highest rate in the western basin occurred at station 4 in the winter of 2023 (86.5%). These sedimentation rates and TSS levels are crucial for both the future of settled and mobile aquatic communities (biotic future) and the longevity of the artificial reefs themselves (abiotic future). In later stages, these factors will play a key role in determining the success of the A.Rs.