فهرست مطالب farhad kaymaram

King soldier bream is one of the species of family Sparidae, which is commercially and ecologically very important in the Iranian waters of the Persian Gulf and Oman Sea. The species of this family are morphologically very similar to each other and they may be mistakenly known as another species. Therefore, molecular identification of them has to be considered.

In this study, the phylogenetic relationship of king soldier bream fish based on mitochondrial region(CO1) was investigated using DNA sequencing method. For this purpose, 90 samples were collected from the soft tissue of the caudal fin using Ammonium acetate, and its quantity and quality were determined by Spectrophotometry and Electrophoresis. Optimal DNA samples for Polymerase Chain Reaction (PCR) and sequencing were examined. After gene amplification and sequencing, Bio Edit version 7.0.1, BLAST, MEGA 7.0.2 and DnaSP 5.10.01 software were used to draw phylogenetic trees.

Based on the phylogenetic tree obtained from the sequences, king soldier bream was divided into two main branches in Bandar Abbas, Bandar Bushehr and Bandar Chabahar areas. All samples of the first branch showed a sister relationship with the second branch and all the samples of branches one and two showed sisterhood with samples KJ012292 and kJ012291 from the Gene Bank in Italy with 82, 67 and 86% accuracy.

The results can provide useful information on the conservation and management programs, for the preservation, revitalization, and resource of the population this valuable species.

This study was conducted to feeding behavior of the Malabar trevally (Carangoides malabaricusin( in the Persian Gulf and Oman Sea. This study was conducted on the diet of the Malabar trevally (C. malabaricus) in the Persian Gulf and Oman Sea (Hormozgan province) for 12 months from December 2016 to November 2016. Sampling was done with trawl nets and expected nets. 438 specimens of the Malabar trevall (C. malabaricus) were selected for dietary examination. Results of descriptive bioassay data indicated that the maximum total length was 365 mm (in May) and the minimum total length was 140 mm (in September) and the maximum weight was 534.5 g and minimum was 57.8 g. During the study period, the mean total fish length was 261 ± 18.41 mm and the mean fish weight was 191.78 25 25.35 g. The GASI index showed a peak feeding in June. Gastric emptying index (CV) for this species was 62.33% during the study, which can be said to be a relatively small fish. In terms of the type of food eaten, due to the volume of digested fish, Leognathus. Sp,Encrasicholina punctifer fish is considered to be the staple food for the Malabar trevall. Shrimp can be eaten as a side dish, and other varieties eaten as squid and crab can be considered as a random meal.

To achieve comprehensive management of marine resource stocks requires knowledge of the variables that affect economic species. Longtail tuna (Thunnus tonggol) is one of the most economic species in the southern waters of Iran. Recent study tried to find out the association between the most important satellites derived environmental variables with longtail tuna catch and distribution by applying Generalized Additive Model (GAM) in the southern waters of Iran. Results indicated the relatively high importance of temporal (month of fishing), spatial (latitude), and three environmental variables as Sea surface salinity (SSS), mixed layer depth (MLD), and Sea surface temperature (SST). Deviance explanation of the GAM model defined as 62.3% and adjusted R-square was 0.595. Maximum Entropy (MaxEnt) habitat suitability modeling by selected tree environmental variables shows longtail tuna inhabited mostly in latitude between 24°N and 26°N close to Hormozgan and Sistan and Balochistan province waters. The current study by detecting most important satellite derived environmental variables and high suitable habitat, could assist decision makers and fishery managers to improve fishing efficiency of Iranian purse seiners and helps implementation of ecosystem-based fisheries management of shared stocks in southern waters of Iranian.

This study was conducted to evaluate the Yellowtail scad feeding (Atule mate) in the Persian Gulf and  Oman Sea (Hormozgan province) by gill net fishing from Dec.2016 to Nov.2017 monthly and seasonally.  Gastro-somatic index (GASI), CV , food preference index (FP), and frequency of food items were determined  from 447 specimens. The maximum point of GaSI index was shown in June. The CV index for this species during the study was 65.32% . According to the volume of fish digested, Encrasicholina punctifer and Sardinella sp were the basic and secondary foods , respectively. Squid and crustaceans could be considered as the incidental foods. Regarding to the species diversity of Carangidae family and importance of relation between food items, it is recommended that comprehensive feeding study of all species of this family should be carried out .