A study on the lipid distribution pattern in muscles of two teleosts, Arius dussumieri and Ophiocephalus striatus

The muscles of the various regions and zones of the body of the two teleosts, A. dussumieri and O. striatus have been analyzed for lipid contents. There is a significant dorsum-ventral gradient in lipid concentration exhibited by both the fishes with higher lipid values in the ventral aspect of the body, especially the belly flaps. As regards the vertical series, both the fishes exhibit comparatively higher lipid contents at the dorsal aspects of the caudal region and at anterior portion of the dorsal fin area with lower lipid values at cephalic and middle portions of the body. The red muscle of Arius exhibits higher lipid content than the white muscle.

Distribution pattern of some biochemical constituents in muscle of the common cat fish, Heteropneustes fossilis (Bloch)

The quantitative distribution pattern of fat, moisture, protein and ash has been studied in the muscle of the various zones corresponding to the dorsal and ventral regions of the body of a common cat fish, H. fossilis (Bloch). The ventral part of the body showed more accumulation of fat and ash than the dorsal part, while this dorso-ventral gradation was not marked in the case of protein content. All the four constituents also showed an increase from the anterior to the posterior zones, both in the ventral as well as dorsal regions of the body. The distribution of moisture followed an almost opposite pattern, indicating an inverse relationship with fat and ash contents.

Identification of biodiversity and distribution pattern of benthic Foraminifera and Ostracoda in continental shelf sediments of the Oman Sea

Biodiversity and distribution of benthic Foraminifera and Ostracoda in the continental shelf sediments of the Omman Sea was studied in order to indicating of the composition of benthic foraminiferal and ostracodal communities and determining of their relationship with the environmental factors of the Omman Sea. Sediment samples were gathered in winter 2006 from twelve stations ranging in depth from 30 to 103 meters. Environmental factors including depth, temperature, salinity, dissolved Oxygen and pH were measured with a CTD system during sampling time and grain size and total organic matter were measured in laboratory. From the overall 57 benthic foram species, there were 52 identified species belong to 25 genera of 16 families. The cosmopolitan foraminifer, Ammonia beccarii, was common in all sampling stations. The composition of benthic foram communities had a highly positive correlation with depth, salinity and total organic matter. From the overall 30 ostracod species, there were 26 identified species belong to 22 genera of 13 families. Diversity and aboundance of ostracoda of the Oman Sea decreased from east to west and from south to north but increased slightly in the northwest (near the Strait of Hormoz). Ostracoda of the genus Propontocypris were common in all sampling stations but the genera Cyprideis, Paradoxostom and Hemicytheridea were rare in the Oman Sea. Diversity and aboundance of ostracoda in northern regions were less than southern and were less than foraminifera too. The composition of ostracodal communities had a highly positive correlation with dept, salinity and grain size. Biodiversity and distribution pattern of benthic foraminifera and ostracoda were being different in various sampling stations, especially between northern and southern regions. Water depth, salinity and structure of the sediments were the most important abiotic factors controlling the distribution pattern of benthic foraminifera and ostracoda in the Omman Sea. None existence or rare observation of structural abnormalities and oil polluted individuals in the vicinity of all sampling stations, resulted to the "clean" benthic environment of the Omman Sea.

Batho-spatial distribution pattern and biomass estimate of the major demersal fishes in Lake Victoria

A generalized bottom trawl exploratory survey was carried out on Lake Victoria to: (i) define the distributional pattern and magnitude of the lakewide demersal stocks, (ii) determine the commercial potential of Haplochromis spp. and (iii) evaluate trawling as a commercial fishing technique for Lake Victoria fisheries. Preliminary results suggest that: (i) bottom trawl catches are more representative of the stocks, (ii) species diversification and fish density decrease with increasing mean depth and (iii) at least 80%of the catchable demersal ichthyomass is Haplochromis. Though bottom trawling is a much more efficient fishing technique for the Lake Victoria fisheries, bio-socio-economic consideration impose that mechanization of the fishery should better proceed in graded steps. Besides demographic and nutritional considerations indicate the necessity for rational management and increased direct human utilization of the fishery resource.

Ecological health analysis of Caspian marine environment based on the diversity and distribution pattern of meiofauna in the Mazandaran Province, Caspian Sea

Biodiversity and distribution of benthic meiofauna in the sediments of the Southern Caspian Sea (Mazandaran) was studied in order to introducing and determining of their relationship with the environmental factors. From 12 stations (ranging in depths 5, 10, 20 and 50 meters), sediment samples were gathered in 6 months (2012). Environmental factors of water near the bottom including temperature, salinity, dissolved oxygen and pH were measured during sampling with CTD and grain size and total organic matter percentage and calcium carbonate were measured in laboratory. In different months, the average water temperature (9.52-23.93), dissolved oxygen (7.71-10.53 mg/L), salinity (10.57±0/07 and 10.75±0/04 ppt), pH (7.44±0/29 and 7.41±0/22), EC (17.97±0/12 and 18.30±0/04μs/cm2), TDS (8.92±0/04 and 9.14±0/02 mg/L), total organic matter (5.83±1/43 and 6.25±0/97%) and calcium carbonate (2.36±0/36 and 1.68±0/19%) were measured respectively. Structure of the sediment samples mostly consisted of fine sand; very fine sand, silt and clay. From the 4 group animals (Foraminifera, Crustacea, Worms and Mollusca), there were identified 40species belong to 29 genera of 25 families. The cosmopolitan foraminifer, Ammonia beccarii caspica, was common in all sampling stations. Result showed that depth was important factor on distribution of meiofauna. Most density of foraminifera and crustacean was observed in depth of 20m and for mollusca and worms observed in 5m. Shannon diversity index decreased with depth that showed in shallow water diversity was higher than deep water. Mean of maximum and minimum Shannon index was obsorvers in depth of 5m and 50 m that was measured in order 0.93 and 0.43. Account of Shannon index showed that this area is under pressure. Account of peioleo index showed distribution in this area was not steady.

Determination of biodiversity and spatial and temporal distribution pattern of demersal fishes in the Oman Sea

In this project, have been studied to determine the appropriate model to spatial, temporal and diversity of demersal fishes in the Sea of Oman, including Trichiuridae, Nemipteridae, Haemulidae, Arridae, Synodontidae, Batoidfishes, Carangidae, Scianidae, Carchariniformes and Serranidae. This research became operational from catch data during 2003 to 2013 (in 2007, due to the lack of ship failed). Processing and calculations was evaluated by using the software Excel, SPSS, Arc GIS and table curve 3D highest biomass and abundance was showed in strata A and C and 10-30 m depth layers was showed the best condition biomass. In other words, highest biomass was showed in the eastern region in the Oman Sea than the central and western regions. Batoidfishes and Trichiuridae had the highest biomass .Depth factors was showed a significant correlation with the biomass. Scianidae, Serranidae and Haemulidae were showed a large decline. Synodontidae was showed a very large increase. The largest of Shannon index belong to central and western region of the Oman Sea. The highest Shannon index was showed 10-20 and 50-100 m, respectively. The Distribution maps based on the biomass was analyzed by using Arc GIS software. So that were identified in the first time in a ten-year period and carefully catch stations any economic of aquatic group. In conclusion, the depth can be found in the pattern of distribution, abundance and diversity of fish from away the beach so that follow specific pattern.

A review on systematic and taxonomic of the Persian Gulf fish species, based on geographical distribution pattern and habitat diversity, using by GIS

During the period from 2011 - 2015 with the aim of this study was to systematically review and in particular the revised classification of the Persian Gulf (and the Strait of Hormuz) and to obtain new information about the final confirmed list of fish species of Iranian waters of the Persian Gulf (and Hormuz Strait), samples of museums, surveys and sampling, and comparative study of all available sources and documentation was done. Classification systematic of sharks and batoids and bony fishes. Based on the results, the final list of approved fish of the Persian Gulf (including the Strait of Hormuz and Gulf of Oman border region) are 907 species in 157 families, of which 93 species of fish with 28 cartilaginous families (including 18 families with 60 species and 10 families with 34 species of shark and batoids); and 129 families with 814 species of bony fishes are. The presence of 11 new family with only one representative species in the area include Veliferidae, Zeidae, Sebastidae, Stomiidae, Dalatiidae, Zanclidae, Pempheridae, Lophiidae Kuhliidae, Etmoptridae and Chlorophthalmidae also recently introduced and approved. The two families based Creediidae Clinidae and their larvae samples for newly identified area. 62 families with mono-species and 25 families with more than 10 species are present including Gobiidae (53), Carangide (48), Labride (41), Blenniidae (34), Apogonidae (32) and Lutjanidae (31) of bony fishes, Carcharhinidae (26) of sharks and Dasyatidae (12) in terms of number of species of batoids most families to have their data partitioning. Also, 13 species as well as endemic species introduced the Persian Gulf and have been approved in terms of geographical expansion of the Persian Gulf are unique to the area.Two species of the family Poeciliidae and Cyprinodontidae have species of fresh water to the brackish coastal habitats have found a way;in addition to 11 types of families Carcharhinidae, Clupeidae, Chanidae, Gobidae, Mugilidae, Sparidae also as a species, with a focus on freshwater river basins in the south of the country have been found. In this study, it was found that out of 907 species have been reported from the study area, 294 species (32.4 %) to benthic habitats (Benthic habitats) and 613 species (67.6 %) in pelagic habitats (Pelagic habitats) belong. Coral reefs and rocky habitats in the range of benthic fish (129 species - 14.3 %) and reef associated fishes in the range of pelagic fishes (432 species – 47.8 %), the highest number and percentage of habitat diversity (Species habitats) have been allocated. As well as fish habitats with sea grass and algae beds in benthic habitat (17 species- 1.9 %) and pelagic - Oceanic (Open sea) in the whole pelagic fish (30 species – 3.3 %), the lowest number and percentage of habitat diversity into account. From the perspective of animal geography (Zoogeography) and habitat overlaps and similarities (Habitat overlapping) fish fauna of the Persian Gulf compared with other similar seas (tropical and subtropical, and warm temperate) in the Indian Ocean area - calm on the surface, based on the presence of certain species that the fish fauna of the Persian Gulf to the Red Sea and the Bay of Bengal (East Arabian Sea) compared to other regions in the Indian Ocean (Pacific) is closer (about 50%), and the Mediterranean (East area) and The Hawaiian Islands have the lowest overlap and similarity of habitat and species (about 10%).

Recent trends in the distribution patterns and catch rates from trawl surveys in Lake Victoria, Tanzania

Trawl surveys to assess the stocks of Lake Victoria (Tanzania) for estimates of biomass and yield, together with the establishment of exploitation patterns, are being undertaken under the Lake Victoria Fisheries Research Project. Preliminary surveys to establish the sampling stations and strategy were carried out between October 1997 and February 1998. Three cruises to cover the whole of Tanzanian waters were undertaken with 133 sampling stations. Data on each rates, species composition, and distribution were collected. Three sampling areas were designated: area A, B and C. In each area, almost the same distribution pattern over depth was found. Lates niloticus (L) formed over 90% of the total catch. Most L. niloticus were from 5-40 cm TL. Abundance decreased with depth, few fish were found deeper than 40m and most fish were caught at <20 m deep. Catch rates varied considerably between stations and areas. Area A had the highest catch rates with little variation over the stations. There is an indication of recovery of species diversity compared with the surveys of RV Kiboko(1985 and 1989)

Histological distribution and ultrastructure of exocrine pancreas in Indian major carp (Labeo rohita Ham.) and its alteration in aflatoxicosis

The distribution pattern of exocrine pancreas in Labeo rohita besides its general location along the course of intestinal mesentery was studied. It is evenly distributed within the liver around portal vessels and also within the spleen near a blood vessel. On ultrastructure, two cell types of different degrees of staining intensities containing abundant rough endoplasmic reticulum, mitochondria, pre-zymogen and zymogen granules were marked. During aflatoxicosis, the mesenteric pancreas and hepatic pancreas were mostly affected revealing necrotic changes to acini. The zymogen granular activities were markedly reduced. Ultra structurally, the rough endoplasmic reticulum was fully dilated and formed whorled pattern. The damage to the exocrine pancreas might be affecting digestive enzymes' secretion which may be one of the causes of aflatoxin-induced anorexia in fish.

Seasonal variation in the distribution and availability of Carangids ("Paraw" and "Parati") in the Wadge Bank

The Wadge Bank has been exploited regularly by Ceylon based trawlers since 1955 (Sivalingam & Medcof 1957). The bank is about 4,000 sq. miles in extent (Malpas 1926) and is located south of Cape Comorin within the Continental Shelf of India (Fig. 1). Carangids are taken in large numbers during the months of the south west monsoon (Sivalingam 1966). The quantity, in which the Carangids are captured as shown by the fishing records, is large enough to influence the total catch from the bank during these months (Fig. 2). Carangids are held in high esteem as excellent quality food fishes and accordingly constitute a commercially important group. This paper records the results of a detailed examination of the past fishing records in respect of this group, based on the analysis of the catch and fishing effort for the years 1957 to 1962. The distribution pattern of this group of fish in the Wadge Bank is discussed.

Social and economic implications of the fishery distribution patterns on Lake Victoria, Uganda

The fisheries of Lake Victoria have undergonea dramatic transformation during the last two decades. From being a locally based fishery with little intervention and capital investment from outside,the present fishery is dominated by national and international capital penetrating the industry. It is explosion in the growth of nile perch and the strong demand devloped for this fishin the global markets, which have transformed the fisheries of the Lake victoria. This report presents the results of a survey carried out between October 2001 and February 2002 about the fishery distribution patterns and their impacts on fisher communities of Lake Victoria. The fisheries distribution pattern of the lake is described as well as the flows and benefits from the fisheries resource and the resource constraints and sustainability options. A major part of the paper discusses some of the socio-economic impacts of the rapid changes that are responsible for the present fisheries. It particularly focuses on the effect of the Nile perch boom, its globalization and the development of the fish industry in Uganda, on food security and employment for the local population.

Spezifizierungsanalyse des Quecksilbers - ein möglicher Beitrag zur Erforschung der Auswirkungen klimatischer Veränderungen auf die belebte Meeresumwelt

The predominantly occurring chemical forms (species) of mercury (Hg) that occur in the environment are elemental mercury (Hg0), divalent inorganic mercury (Hg2+) and dimethylmercury (CH3HgCH3) and monomethylmercury(CH+3Hg), the latter of which is strongly accumulated by marine organisms. Conversions between the different mercury species provide the basis of the complex distribution pattern of mercury on local, regional, and global scales. An analytical system using hyphenated instrumental techniques has been developed and validated in order to determine inorganic and organic mercury species in marine biota (fish and plankton). It is suggested than mercury species analysis can provide a useful tool to investigate the effects of climate changes on the bio-transformation activity of certain marine microorganisms.

A review of the commercially exploited marine fishery resources of Nigeria

The annual estimated total marine fish catch in Nigeria for the period 1971 to 1979 is 0.3299 million metric tons. The differential distribution pattern of the predominant fish groups for the maritime states, the component species, their life habits in relation to hydrographic factors leasing to seasonal fluctuations in the fisheries are highlighted, focussing also on the types of fishing carafts and gear in common use along the coastal states and the fish species obtained from them. The landings by the exploratory and commercial fishing trawlers including the distant water vessels (imports) form about 4.24% of the total marine fish landing

Recent progress in the identification and determination of freshwater phytoplankton in the natural environment

The biomass of the phytoplankton and its composition is one of the most important factors in water quality control. Determination of the phytoplankton assemblage is usually done by microscopic analysis (Utermöhl's method). Quantitative estimations of the biovolume, by cell counting and cell size measurements, are time-consuming and normally are not done in routine water quality control. Several alternatives have been tried: computer-based image analysis, spectral fluorescence signatures, flow cytometry and pigment fingerprinting aided by high performance liquid chromatography (HPLC). The latter method is based on the fact that each major algal group of taxa contains a specific carotenoid which can be used for identification and relative quantification of the taxa in the total assemblage. This article gives a brief comparative introduction to the different techniques available and presents some recent results obtained by HPLC-based pigment fingerprinting, applied to three lakes of different trophic status. The results show that this technique yields reliable results from different lake types and is a powerful tool for studying the distribution pattern of the phytoplankton community in relation to water depth. However, some restrictions should be taken into account for the interpretation of routine data.

Contribution à l'écologie de quelques taxons du zooplancton de Côte d'Ivoire. 2 - Dolioles, Salpes, Appendiculaires

The seasonal variations of vertical distribution and abundance over the shelf are investigated for Doliolids, Salps and Larvacea. The 3 groups present many similar ecological features. Two maxima of abundance occur during the little and main cool seasons. The second maximum is usually the most important, except for Salps. The 3 taxons inhabit more superficial layers in cool than in warm seasons. This allows them to follow the phytoplankton maximum which drifts near the thermocline during the warm season. Pelagic Tunicates come back to the phytoplankton enrichment areas by the deeper Ivorian under-current. A relationship between the vertical distribution pattern and the life cycle (sexual or asexual generation) is suggested.