Feeding habits and trophic levels of some demersal fish species in the Persian Gulf (Bushehr Province) using Ecopath model

A trophic study was carried out in February of 2012 to January 2013 on the ecosystem in the Persian Gulf, Bushehr provience. A total of 2,948 samples of stomach contents were analyzed based on the weight and number of food items and were identified about 40 preys. Crustacean and bony fish were as a main prey in most of the stomach contents . The mean average trophic level was estimated at 3.6 by Ecopath software. In this research, the mean level were studied between eight species varied from 3.47 to 4.61, Saurida tumbil occupy the highest and the Argyrops spinifer was the lowest level. The ranges of total mortality varied from 0.7 to 3.05 per years. The food consumption rate was estimated about 69.82 per year. The overlap index showed that the prey items such as fish, crustacean, bivalve and echinoderm were shared about 65, 15, 15 and 6 percent in all stomach of individual in respectively. Mixed trophic analysis indicates that benthos have a positive effect on most of the fish species. Most species have a negative impact on themselves, interpreted here as reflecting increased with in group competition for resources. This preliminary model can be helpful to determine the gaps in the present knowledge about demersal system of the Persian Gulf

Growth, mortality and spawning season of the spangled emperor (Lethrinus nebulosus Forsskal, 1775) in coastal waters of Hormozgan Province in the Persian Gulf and Oman Sea

The population parameters and spawning season of the Spangled emperor (Lethrinus nebulosus) were studied in coastal waters of Hormozgan province. The monthly calculated mean values of gonadosomatic index (GSI) of females were indicate to increase from February, reach the highest in March and decline in June. The spawning season peak of L. nebulosus occurred in March. The Von Bertalanffy growth parameters, L∞, K and t0 were estimated as, 67.2cm, 0.16.year^-1 and -1.161 year, respectively. The relationship between weight and length (Fork Length) can be expressed as W=0.051 L^2.722, which indicates that Spangled Emperor has negative allometric growth. Using length converted catch curve, total mortality (Z) was estimated as 1.13 year^-1 and natural mortality was estimated using Pauly's equation, as 0.57 per year. Finally, the fishing mortality (F) was 0.56, which gives an exploitation rate (E) of 0.50

Growth parameters and mortality rates of Liza klunzingeri in the Iranian waters of the Persian Gulf and Oman Sea, using Length Frequency Data

The aim of the present study was to investigate the population dynamics of Liza klunzingeri, in Hormouzgan province waters located in northern coasts of the Persian Gulf and Oman Sea. This study was carried out from October 2007 to September 2008. Samples were collected from commercial stake traps. The relationship between weight and fork length was found to be W= 0.0214 F.L^2.8233 suggesting that Liza klunzingeri shows isometric growth. Length-based stock assessment using the FiSAT software package showed an asymptotic length (L∞) of 20.3cm FL and growth coefficient of 0.6.yr^-1. These results gave a growth performance index (ø) of 2.39. The total mortality coefficient was estimated to be 2.31, a natural mortality of 1.09 and fishing mortality of 1.22. The estimated total mortality which, in relative terms, is considered average (2.31.yr^-1), coupled with the currently observed exploitation rate of 0.52 for L. klunzingeri, estimated from the mortality rates, suggested that the species is moderately exploited

The reproductive biology and feeding habits of yellow fin seabream, Acanthopagrus latus (Houttuyn, 1782), in the northern Persian Gulf

Monthly samples of Acanthopagrus latus (Houttuyn, 1782) were used to determine (1) feeding habits and (2) reproduction characteristics of the species in relation to its size, spawning season and sex in the northern part of the Persian Gulf from January to December 2013. The smaller length classes of all samples were dominated by male fish. All gonads examined, were ovotestis during the spawning period from February till May. Male and female ovotestes were dimorphic in structure which represented a transitional stage in a protandrous sex change. Length at first sexual maturity of female A. latus was 24.40 cm. A. latus fed predominantly on bivalves, gastropods, cephalopods, stomatopods, fish and decapods which showed changes according to the season and body size. According to our results, it appears that A. latus feeds throughout the year; the highest value of gastrosomatic index (GaSI) for both sexes was recorded in February, which was significantly different from that in other months. The results of this study also indicate that feeding in yellowfin seabream is very intense before reproduction (during January and February). It decreases gradually after February to June during the spawning season

Road map of warm water fish culture

Carp aquaculture is one of Maine potential for commercial and rural development, employing enhancement and earning income .This enterprise which is conducted by using fresh water and unfertile lands have been attended in the country since last seven decades. In accordance to wide area of cultivation in the country, maximum production is about 150000 tonnes in 2010. Establishment of aquaculture center by technical deputy of president, made a suitable opportunity for preparation of carp development road map. In this report, present condition and problems in front of carp development have been analyzed, and regarding to targets of long term country development, projects for research and executive sectors have been prepared

Environmental and ecological studies in northern Alborz (Guilan Province)

Caspian Sea with an area of 400 thousand square kilometers is the largest lake in the world. The Caspian Sea about 1200 km from north to south on the longest section and an average width of 320 km. along the coastline around the Caspian Sea is about 6500 kilometers. Caspian Sea is about 78,000 cubic kilometers of water volume that is 44% of stocks of blue lakes around the world. Caspian Sea basin, which is composed of seven major basins of the main watershed from west to east are: juniper, Talsh- Anzali, large Sefidrood between Haraz Sefid and, Hraz- Gharehsou, Nagorno Sv- Gorgan and Atrak in the basin of Aras no limits to the beach. Aras sub-basin is located in the North West and Iran, the second largest sub-basin of the Caspian Sea. Talysh-Anzali on the Caspian Sea basin West and the seventh largest sub-basin of the Caspian Sea. White basin is located in the South East of the Caspian Sea and the extent of the sub-basin of the Caspian Sea. Haraz located in the south Caspian Sea basin and the ninth largest sub-basin of the Caspian Sea. Gorgan is located in the South East of the Caspian Sea basin and the fourth largest sub-basin of the Caspian Sea. In these areas, about 28 percent of the total fish production in the northern waters of aquatic allocated

Analysis of sturgeon fishes reproduction statistics on the northern part of Alborz region

Out put of sturgeon fish hatcheries on the Northern provinces analyzed. Unfortunately, for many reasons such as decreasing of brood fishes ,unsuitable and unprofessional managements, lack of sufficient financial supports, ageing of laboratory and incubation instruments, unemployment of energetic expertise sturgeon propagation and restocking programmes get decreasing trends. Thus managers must planning for activating of sturgeon restocking and propagation subjects

Environmental and ecological studies in northern Alborz (Golestan Province)

Caspian Sea with an area of 400 thousand square kilometers is the largest lake in the world. The Caspian Sea about 1200 km from north to south on the longest section and an average width of 320 km. Along the coastline around the Caspian Sea is about 6500 kilometers. Caspian Sea is about 78,000 cubic kilometers of water volume that is 44% of stocks of blue lakes around the world. Caspian Sea basin, which is composed of seven major basins of the main watershed from west to east are: juniper, Talsh- Anzali, large Sefidrood between Haraz Sefid and, Hraz- Gharehsou, Nagorno Sv- Gorgan and Atrak in the basin of Aras no limits to the beach. Aras sub-basin is located in the North West and Iran, the second largest sub-basin of the Caspian Sea. Talysh-Anzali on the Caspian Sea basin West and the seventh largest sub-basin of the Caspian Sea. White basin is located in the South East of the Caspian Sea and the extent of the sub-basin of the Caspian Sea. Haraz located in the south Caspian Sea basin and the ninth largest sub-basin of the Caspian Sea. Gorgan is located in the South East of the Caspian Sea basin and the fourth largest sub-basin of the Caspian Sea. In these areas, about 28 percent of the total fish production in the northern waters of aquatic allocated

Investigation of situation of propagation and culture of rainbow trout in north of Alborz

The aquaculture activity in provinces of north of Iran, in spite of fast progressive and possess a series of achievement and success, there was some failure, difficulties, limitation and restriction. To planning for further expansion in this failed, this study is managed. The culture of rainbow trout is practice in individual farms, small farms, water resources, earthen ponds, recycling ponds etc, which each method have its potential, failure and limitation that are consider in the present work. At the end, based on the situation of production in past years, and considering each of factors mentioned above, the success, failure, difficulties, limitation and restriction points of aquaculture of rainbow trout in technical poin of view are investigated and some command for improvement for each production method are presented. The development of aquaculture in recent years is based on extension of farms and increasing density of fish in fish pond. In contrast of many production activities, the propagation and culture of fish is inconstant work. This variability makes a potential for better income, occupation and job, increasing in production etc. This study make a better planning using this activity

Probiotic-associated aspiration pneumonia due to Lactobacillus rhamnosus

Lactobacilli are low-virulence, commensal organisms of the gastrointestinal and genitourinary tracts and are commonly used as “probiotic supplements.” Herein, we describe an episode of respiratory syncytial virus (RSV) bronchiolitis with bacterial superinfection secondary to administration of Lactobacillus rhamnosus in an 11-month-old female with trisomy 21