R. Gilanshahi; S. A. Taghavimotlagh; F. Kaymaram; S. M. R. Fatemi; Gh. Vosooghi
Volume 2, Issue 3 , August 2012, , Pages 197-202
Abstract
The growth parameters, mortality rates and exploitation population dynamic parameters and exploitation rate of Psettodes erumei were assessed between July 2010 to June 2011 using length frequency analysis. The data were collected from landing sites of Jask, Bandar Abass, Kong and Qeshm Hormozgan province ...
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The growth parameters, mortality rates and exploitation population dynamic parameters and exploitation rate of Psettodes erumei were assessed between July 2010 to June 2011 using length frequency analysis. The data were collected from landing sites of Jask, Bandar Abass, Kong and Qeshm Hormozgan province waters. Using total weight (W) and total length (TL) data, the length- weight relationship of this fish species was described as W=00037/L33652/ pertaining to alometric growth. Asymptotic length (L∞) = 74.55 cm, coefficient growth (k)= 0.23 year-1, t0 = - 0.61, longevity (tmax)= 12.43 years and the growth performance index (Φ’)= 3.10 were estimated through the ELEFAN I routine and other modules from the FISAT program. Total mortality (Z), natural mortality (M), and fishing mortality (F) were then calculated as 1.2 year-1, 0.51 year-1, 0.69 year-1 respectively. Although, the estimated exploitation ratio (E= 0.57) was well fitted with the optimum level, careful examination of exploitation rate (U) revealed that the major part of the stock (> 48% length frequency) is being fished out of the defined optimum length. Consequently, the need to improve fishing methods seems mandatory in the future to ensure that total landings do not exceed 525 tons predicted maximum constant yield (MCY).
S. M. R. Fatemi; P. Ghavam Mostafavi; F. Rafiee; M. Saeed Taheri
Volume 2, Issue 1 , March 2012, , Pages 101-106
Abstract
Rocky shores are one of the most important habitats of marine environment in coastal areas. They host marine organisms including seaweeds because of existence of strong and stable substrate for their growths. Intertidal rocky shores are a prominent feature on coastal areas of Qeshm Island located at ...
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Rocky shores are one of the most important habitats of marine environment in coastal areas. They host marine organisms including seaweeds because of existence of strong and stable substrate for their growths. Intertidal rocky shores are a prominent feature on coastal areas of Qeshm Island located at the northern part of Strait of Hormuz. In order to study biomass of seaweeds on rocky intertidal flats of this island, four stations in the south and one station in the northern part of the island were selected. Sampling was done for two periods, summer and winter. It was done during the low spring tide using a quadrate thrown manually and randomly at three times at upper, middle and lower parts of the flats with three replicates. Altogether 73 species of algae were collected and identified. These include 20 Chlorophyta, 10 Phaeophyta and 43 Rhodophyta. The maximum and minimum algal biomass of all stations was recorded in S4 station (117 g.m-2) and S5 station (24 g.m-2) with significant difference between the two stations (P<0.05). Also, the maximum algal biomass was observed for red algae (126g.m-2).
S. M. R. Fatemi; Gh. Vossughi; P. Ghavam Mostafavi; F. Bahri
Volume 2, Issue 1 , March 2012, , Pages 115-120
Abstract
Rocky shores are one of the most important habitats of marine environment in coastal areas. This study was done in 2010-2011 to investigate the diversity of true crabs in intertidal rocky shores of Qeshm island. Samples were collected from intertidal zones during the low-tide at 5 stations. The specimens ...
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Rocky shores are one of the most important habitats of marine environment in coastal areas. This study was done in 2010-2011 to investigate the diversity of true crabs in intertidal rocky shores of Qeshm island. Samples were collected from intertidal zones during the low-tide at 5 stations. The specimens were fixed in 70% Etanol and transferred to laboratory for identification. Altogether, 15 crab species belonging to 8 families and 14 genus were identified. 4 species were from Portunidae, 3 species from Eriphiidae, 2 species from Majidae,2 species from Grapsidae were identified. The others families including Euryplacidae, Leucociidae, Pilumnidae and Xanthidae families have the lowest species richness with only 1 species per family. Portunidae family with 4 species in intertidal zone had the highest species richness amongst studied stations. 3 species of Eriphia smithi from Eriphiidae family, Leptodius exaratus from Xanthidae family and Thalamita crenata from Portunidae family were present at all three intertidal zones (High tide, Mid tide and Low tide).