Population of sand goby (Neogobious fluviatilis pallasi) in southwest coasts of the Caspian Sea using morphological characteristics

Caspian sand goby, Neogobius fluviatilis pallasi belongs to Gobiidae family. Because of their abundance in Caspian Sea, they have important role in the sea food chain in this area. This study was conducted from October 2005 to September 2006 in southwest coasts of the Caspian Sea in Guilan province. Samples were collected monthly from four stations (Astara, Anzali, Chamkhaleh and Chaboksar coasts) from coastal areas to waters l5 meters deep using bottom trawl. Result of differential function analyses on corrected morphometric statistic showed three functions 51.3%, 28.4% and 20.3%, respectively, and sum of differentiative function percentage was 80% which proved difference among groups. The functions showed that samples in Astara station were completely different from other regions while they were similar to Anzali station only in some sampling points. Chamkhaleh and Astara stations were the same but Chaboksar station was a separated group. Analysis of differential functions for studied characteristics included on average 86.3% of the population with most of it belonging to Astara station (93.3%) and Anzali (90%). The minimum amount belonged to Chamkhaleh with 79.3%. The results showed that Neogobius fluviatilis pallasi probably has three different populations in Astara, Anzali, Chamkhaleh and Chaboksar populations

An investigation on some biological characteristics of Capoeta buhsei in Gharachay River, Saveh

In this study we investigated biometric and morphometric traits of Capoeta buhsei in Gharachay River, Saveh. Sampling was in 5/90, 11/90 and 8/91. Sampling was by electroshoker. Samples after catching transferred to Azad university of Babols labratoar and investigated. Measurement of length was recorded by digital caliper to the nearest 0/01 mm and weight was recorded by digital balance to the nearest 0/01 g .Age determination was by observing scales in benicular loop with 40..Results of investigation of 53 male and 39 female of this species indicated that mean standard length of male and female was 131/46±23/59 mm and 152/96±25/07 mm respectively. Ratio of female to male was 0/73 :1 and with x2 -test there wasn’t a meaningful relashionship between male and female ratio

Comparison of morphometric and meristic attributes of bream (Abramis brama orientalis), in Caspian Sea and Aras Dam Reservoir

Morphometric and meristic specifications of Abramis brama orientalis of the Caspian Sea and Aras Dam Reservoir was studied in the year 2002. For this purpose, 40 morphometric attributes, 16 meristic attributes and 37 specifications in relation to the proportions of speciality of morphometric attributes of the Abramis brama orientalis were evaluated from the two habitats. Anova, factor and discriminant function analyses were conducted on the data. According to results the average coefficient of variation in morphometric, meristic and proportion of speciality of morphometric attributes for Abramis brama orientalis of Caspian Sea was 22.85, 3.24 and 7.68 and for Abramis brama orientalis of Aras Dam Reservoir was 17.45, 3.53 and 15.27. The Abramis brama orientalis of the two areas showed meaningful differences in 35 morphometric factors, 6 meristic factors and 25 factor of proportion of the speciality of the age had significand differences (P<O.05). Factor analysis showed that the Abramis brama orientalis of the two habitats had 80.62% of changes in 7 factors of first morphometric attributes, 73.65% of changes in the 9 factors of the first proportion of morphometric specialities and 46.52% of changes in the 4 factors of the first meristic attribute. We showed that, fork length, standard length, proportion of head length to the standard length, number of scales of the lateral line, number of scales under the lateral line, number of scales above the lateral line, radius of dorsal fin and number of dorsal fins can be used to separate population of the fish from the two habitats. The first two factors of proportion of speciality of morphometric and meristic attributes causes total separation of the two populations. We found different in morphometric specialities between the two specialities of morphometric and meristic attributes. It is suggested that different environmental conditions have led to the differences in the populations of the fish in the Caspian Sea and Aras Dam Reservoir

Studying native fishes in Hamadan province

Studying native fishes of Hamadan province have been done in 159 stations from 51 important water resources (wetland, reservoir, spring, river and qanat) using with electric tool, cast-net, seine and gill-net gears from July 2010 to Oct. 2011 and the main aims were species identifying and determining their distribution and abundance in the studied area. In the study, 33411 fish specimens are caught in 257 times of sampling and selected randomly about 8500 individual and laboratory works showed the fish belong to 37 species from 7 families. Cyprinidae with 25, Nemacheilidae with 6 and Sisoridae with 2 species had the most diversity and Cobitidae, Poeciliidae, Salmonidae and Mastacembelidae had only a representative. 31 fish species were native or endemic and 6 species were alien. Fish species existed in all rivers of Ghezelozan and Sirvan sub-basins but there were not any fish in 10 rivers of Ghara-Chai sub-basin and in 6 rivers of Gamasiab sub-basin, too. Also, it was observe 1-3 fish species in 15 rivers, 4-6 fish species in 10 rivers, 7-10 fish species in 5 rivers and more than 10 fish species in 4 main water resources and Gamasiab sub-basin with 32 fish species was the most diversified and Ghezelozan sub-basin with 2 fish species was the least diversified. There were any species to 4 (mostly 1 or 2) fish species in studied qanats in Ghara-Chai and Gamasiab rivers sub-basins. 23 fish species existed in a subbasin, 12 species in 2 sub-basin, Capoeta capoeta in 3 sub-basin and Squalius cephalus in all sub-basins of studied area. Alburnoides nicolausi,Capoeta aculeata and Alburnus mossulensis have had the most frequency. Studying fish abundance showed Oxynoemacheilus argyrogramma with 17.8%, Garra rufa with 12.3%, A. mossulensis with 12.1% and C. aculeata with 10.2 % of total number of caught fish specimens are dominant. S. cephalus, Capoeta damascina, C. aculeata, C. trutta, Chondrostoma regium and A. mossulensis have had sport fishing value but Acanthobrama marmid, Oxynoemacheilus kiabii, Oxynoemacheilus kermanshahensis, Turcinoemacheilus kosswigi, Alburnus caeruleus and Mastacembelus mastacembelus have biodiversity value for being endemic or having limited habitats in Iran

The feasibility study for culture of Salmo trutta caspius by brackish water

Caspian trout is valuable, Commercial, anadromous and endemic fish species in the Caspian Sea so that, researchers attention have been focused on this species. At the moment, only pay attention to stocks rehabilitation that fisheries organization releases more than 300,000 fingerlings to the rivers ends to the Caspian Sea. Importance of this study consist (1) introducing a new species to the aquaculture system and (2) provide breeders in this research. we used from 2 treatments that consist with density of 10 kg/m^3 and 20 kg/m3 with 3 replication. Results showed, culture of Caspian trout is suitable with density 10 kg/m^3, so that weight gain, SGR and Daily growth mean are better than treatment 2(15-20 kg/m^3

Biological survey of Caspian kutum (Rutilus kutum) released fingerlings in Sefidroud River (Guilan Province)

Kutum fish (Rutilus kutum) is an anadromous cyprinid species that spawns in adjusted rivers to the Caspian Sea. Many million fingerlings were artificially produced and annually released in these rivers specifically in Sefidrud River by Iranian Fisheries Organization. In this study were estimated the staying period of Kutum fingerlings in Sefidrud River and its diet and growth. A small piece of the caudal fin was cut as a tagging method. About 50000 and 5200 individuals were marked during July and September 2013, respectively. The marked fish had an average total length 53.2±5.6 mm and body weight 1.11±0.26 g and were released in river around two kilometers of the estuary. The sampling of fishes had been earlier started from Feb. 2012 and continued until Feb. 2013 at five stations. Four stations were along river from three Kilometer of estuary to estuary and one station was in right side of estuary in the sea coast. The results showed that marked samples after releasing time were distributed in all studied area from 3 kilometers of estuary to estuary but they migrate mainly toward Caspian Sea in a short time. However the marked samples were observed in estuary and the sea coast after 6 and 24 hours of their releasing time, respectively, Kutum fingerlings remained in Sefidrud river ecosystem in a longer time, at least until end of our sampling period i.e. 105 days. The coefficient of vacuity index of the natural feeding study was 0.0, 49.0 and 30.6 % for phytoplankton, zooplankton and benthos, respectively. The average of GastroSomatic index, intensity of fullness and condition factor were calculated 6.30±3.25, 174.6±153.2 and 0.92±0.09, respectively. A temporal and spatial variation on main food items were observed in gut content of fish fingerlings from different locations and seasons. Gut contents were generally included 59 genera of phytoplankton, 15 groups of zooplankton and 10 groups of benthos. Nitzschia, Navicula and Synedra were dominated among phytoplankton genera with 45.83, 18.02 and 15.99 %, respectively. Among zooplankton groups; the Rotaria, Moeina and Difflugia were dominated with 22.30, 20.86 and 15.83%, respectively. Chironomidae and Gammaridae were the main food items among fed benthic animals with 83.67 and 11.15%, respectively. Furthermore 48 phytoplankton genera, 32 zooplankton genera and 6 benthic families were identified in ecosystem of Sefidrud river. Bacillariophyta phylum (with 23 genus), Rotatoria (with17 genus) and Chironomidae family were dominated in each mentioned groups, respectively. It is concluded that the Kutum fingerlings stay in Sefidrud River for a long time, although most of them migrate to Caspian Sea during first month after releasing. However dietary indices were normal in studied samples, the condition factor index seems to be low