Recursos de colección

Aquatic Commons (41.069 recursos)

The Aquatic Commons is a thematic digital repository covering the natural marine, estuarine /brackish and fresh water environments . It includes all aspects of the science, technology, management and conservation of these environments, their organisms and resources, and the economic, sociological and legal aspects.

Subject = Management

Mostrando recursos 1 - 20 de 45

  1. Selectivity of multifilament trammel nets of different mesh sizes on the red mullet (Mullus barbatus L., 1758) in western Mediterranean, Turkey

    Bolat, Y.; Tan, D.
    Three mesh sizes of multiflament trammel nets (22 mm, 24 mm, and 26 mm) were used in Finike bay for red mullet (Mullus barbatus L., 1758). The sampling program was arranged during February to May 2012. Holt (1963) method was used for selectivity of trammel nets. Red mullet was the dominant species in 22 mm mesh size at 52.86%, followed by 25.7% with the 24 mm net and 21.43% with the 26 mm net. On the basis of the results of this study, optimal selectivity lengths of multiflament trammel nets estimated for red mullet were 18.58, 20.27, and 21.96 cm...

  2. Exploration of fishing gear and fisheries diversity of Agunmukha River at Galachipa Upazila in Patuakhali District of Bangladesh

    Md. Rahman, B.; Md. Sazedul Hoque, Z.; Md. Rahman, M.; Nahar, A.
    Agunmukha River is an important water body having plentiful aquatic resources. The fisheries communities in the river are familiar with a diverse range of fishing gear and crafts to catch fish. Therefore, the objectives of the present study were to explore fishing gear and fishing crafts, catch composition of the respective gear and identification of fish biodiversity of Agunmukha River. A step wise validated questionnaire was used for data recording from February 2015 to August 2015. In total, 19 types of fishing gear were identified under 9 major categories. On the other hand, in view of fisheries biodiversity, 47 fish...

  3. Utilization of analytic hierarchy process (AHP) to meet management objectives in fishery industry of the Sea of Oman

    Zeraatkish, S.Y
    This article examines the use of analytic hierarchy process (AHP) to choose a priority for different purposes which have been used in fishery optimal management in the Sea of Oman. There are several stakeholder groups in the multi-objective planning methods. In this study, the AHP is used to determine the preferences (weight) of stakeholder groups for each of the objectives in the fisheries industry. This method is a multicriteria analysis system which is suitable for including the inconsistent opinion of different groups involved in the management. Based on the results, biological targets received higher weights compared to other targets with...

  4. Phylogenetic relationships of the commercial marine shrimp family Penaeidae from Persian Gulf

    Samadi, S.; Ghavam Mostafavi, P.; Rezvani Gilkolaii, S.; Fatemi, M.; Fazli, H.
    Phylogenetic relationships among all described species (total of 5 taxa) of the shrimp genus Penaeus, were examined with nucleotide sequence data from portions of mitochondrial gene and cytochrome oxidase subunit I (COI). There are twelve commercial shrimp in the Iranian coastal waters. The reconstruction of the evolution phylogeny of these species is crucial in revealing stock identity that can be used for the management of fish industries in Iran. Mitochondrial DNA sequences were used to reconstruct the phylogeny of the Penaeus species of marine shrimp. For this purpose, DNA was extracted using phenol-chloroform well as CTAB method. The evolutionary relationships...

  5. Estimating catches with automatic identification system (AIS) data: a case study of single otter trawl in Zhoushan fishing ground, China

    Wang, Y.B.; Wang, Y.
    The sailing tracks of single otter trawl vessels were simulated using cubic hermite spline (cHs) interpolation method based on the automatic identification system (AIS) data of 6 sampled vessels that were fishing in the Zhoushan fishing grounds after the close of the fishing season from September 2012 to January 2013. The vessels’ status (i.e. whether the vessels were fishing or not) were determined based on the integrated information of speed method and the simulated tracks. Generalized additive model (GAM) was built according to the logbook data of the 6 vessels in 2010, and then the GAM was applied to the...

  6. Assessing genetic diversity of populations of bartail flathead (Platycephalus indicus Linnaeus, 1758) in the northern part of the Persian Gulf using AFLP markers

    Fekrandish, H.; Hosseini, S.J.; Kamali, A.; Soltani, M.
    Genetic diversity of six populations of bartail flathead (Platycephalus indicus Linnaeus, 1758) was investigated using amplified fragment length polymorphism (AFLP). A total of 118 reproducible bands amplified with ten AFLP primer combinations were obtained from 42 fishes that were collected from six different locations in the northern part of the Persian Gulf. The percentage of polymorphic bands was 57.06%. Nei’s genetic diversity was 0.1808±0.2074 - 0.2164±0.1903, and Shannon’s index was 0.2675±0.2949 - 0.3280±0.2727. The results of AMOVA analysis indicated that 66% and 34% of the genetic variation occurred within and among the populations and gene flow was 0.6454. The estimated...

  7. Spatial mapping of shellfish marketing in Kure Ultra modern market, Minna, Niger State, Nigeria

    Ibrahim, S.U.; Adama, B.S.; Yakubu, U.P.; Mohammed, A.
    Geographic Information system and Remote Sensing in the field of marketing is used in this study to open up a wide range of its possible applications as the study assessed shellfish marketing in Kure Ultra Modern Market Minna Niger State. The aim was to develop a database of various shellfish product on sale at the market. The demographic profile, socio-economic characteristics of the marketers and problem associated with the marketing, 100 questionnaires were administered the analytical tool used were frequency distribution, tables, percentages and cost-benefit ratio. Returns from the interview and questionnaire were use to verify the result which depicts...

  8. Population dynamics of the shrimp Penaeus semisulcatus in the Yemeni Red Sea waters

    Abdul-Wahab, M.M.
    Length-based analyses were conducted to assess the stock of the green tiger shrimp Penaeus semisulcatus. Monthly carapace length frequency data were collected from commercial catches at two main landing sites on the Yemeni Red Sea coast for eight months. Growth parameters, mortalities, exploitation rate and yield per recruit were estimated for this species in this area. The estimated growth parameters were CL∞ = 44.65 mm, K = 1.2 yr^-1 and to = -0.15 for males and CL∞ = 58.8 mm, K = 1.4 yr^-1 and to = -0.12 for females. The natural mortality coefficient (M) was estimated as 2.19 yr^-1...

  9. Osmoregulatory capabilities of zander (Sander lucioperca) fingerlings in different salinities of the Caspian Sea

    Ahmadnezhad, M.; Oryan, Sh.; Bahmani, M.; Sayad Bourani, M.
    Osmoregulation capabilities of two size groups (1 and 2g) of zander, Sander lucioperca, fingerlings were investigated survival rate, plasma osmolarity, sodium (Na+), chloride (Cl-) ion concentrations and cortisol level within 0, 6, 24, 72 and 240 h after abrupt transfer from freshwater to 7 and 12‰ salinity. Also, some hematological parameters were measured at 240h. The plasma osmolarity and ion concentrations (Na+, Cl-) increased immediately after the transference to 7 and 12‰ salinity, reaching maximum at 72h in 1g and at 24 h in 2g fingerlings, and significantly decreased at 240 h, while the freshwater control group maintained almost constant...

  10. Assessment of the adoption of aquaculture technologies in Niger State, North Central Nigeria

    Sanni, A.O.; Ayanda, J.O.; Alhassan, D.A.; Adebayo, C.O.; Bako, W.S.
    A total of 115 respondents were examined through purposive and cross sectional approach using questionnaire in nine Local Government Areas of the state. About 58% of the respondents were small scale fish farmers with annual income from fish farming being in a range of N151,00O0 to N200,000 per annum. Majority of the respondents fell within the age of 31-50 years, civil servants by occupation and mostly having tertiary education. The respondents generally had positive attitude to fish farming with comparatively high rate of awareness in relation to adoption of 14 aquaculture practices under investigation in this study. Inadequate extension education,...

  11. Assessment of smoked fish packaging in Doron-Baga metropolis, Borno State, Nigeria

    Adah, P.M.
    This study examined how smoked fish are being packaged in Doran-Baga metropolis. A random sampling technique was used purposely to select one hundred and fifty respondents who are currently involve in smoked fish packaging. Data were collected by means of structured questionnaire. Data collected were analyzed using percentages and frequency. Results revealed that smoked fish packaging is predominantly traditional in the study area. Modern method of smoked fish packaging is nearly absent when compared to smoked fisheries resources produced and packaged from the area

  12. Microfinance and aquaculture development for rural women in Nigeria

    Aladetohun, N.F.
    In many developing countries, active agricultural production takes place in the rural areas. The exploitation of natural fish stocks is reaching limits and aquaculture production has not yet fulfilled its potential despite the large expanse of land in our rural areas. Social and economic indicators for developing countries consistently show that women bear the brunt of hardship in poor communities. The World Bank aims to reduce gender disparities by enhancing women’s participation in economic development. The recent transformation in the country pursues microfinance as a poverty alleviation tool capable of improving the living standard of the rural dwellers to promote...

  13. Women's participation in lower Ikpa River fisheries of Akwa Ibom State, Nigeria: a case study of Ifiayong

    Ekpo, I.E.; Udoh, J.P.
    Ifiayong is a small local village market where economically and commercially important fin and shellfishes are landed. It is located very close to the Five Star and Ibom Le Meridian Hotels at Nwaniba beach. Women functioned as transporters, sorters, processors, financiers, distributors and marketers of the thirty-two finfish families, seven shellfish species together with three turtles (reptiles) encountered at the study site. Socio-economic survey revealed that ninety-four women modally aged 46-55years (34; 36.17%) participated in the fisheries and frequently communicated in Efik (40; 42.55%), and were mostly drop-outs (40; 40.56%) in educational level and polygamous (35; 38.30%). The modal family...

  14. Sources and uses of micro-credit in poverty alleviation among fish farmers in Osun State, Nigeria

    Omitoyin, S.A.; Sanda, O.H.
    Aquaculture is one of the fastest growing food production systems in the world, Nigeria inclusive with the bulk of its output currently being produced within developing countries and with expectations for aquaculture sustainable food security and poverty alleviation. However, poverty which is a social condition characterised by the inadequacy of access to basic human needs for the maintenance and socially acceptable minimum standards of living is still prevalent. One of the major obstacles to achieving the objectives of poverty reduction through aquaculture is the inadequate credit facilities to boost production. The study therefore, this study investigates the sources and uses...

  15. Fish trading: a tool for socioeconomic enhancement and poverty alleviation

    Agbon, A.O.; Omoniyi, I.T.; Adeosun, F.I.; Abdul, W.O.; Agbon, C.A.
    A study was conducted in Abeokuta, the Ogun State capital with the objective to investigate if fish trading could be a tool of poverty alleviation and socio-economic enhancement of the status of women in the household. A total of 120 correctly completed, structured and pre-tested questionnaires, out of the 150 administered to respondents, were retrieved for data analyses. Demographic data of the traders showed that all the respondents were women whose ages ranged from 15 to above 45 years. The ages of 33-45 years constituted 33.3% of the respondents while the age bracket of between 27-32 years constituted 23.3%. Majority...

  16. The opinion of fishermen and customers (fish buyers) on middlemen of Doro-Baga fish market, Borno State

    Usman, H.M; Abdulazeez, K.A.
    The study examined the opinion of fishermen and fish buyers on middlemen of Doro Baga fish market. 240 respondents were used as samples with the aid of structured questionnaire, using stratified random sampling technique. Descriptive statistics was used to analyze the data obtained. The study revealed that majority of the fishermen (75%) highly depend on these selling brokers to sell their fish for them because their financial support comes from the selling brokers, moreover they do not have a stand in the market. Among the fish buyers, especially those that buy directly for consumption, see the brokers as people that...

  17. Micro-credit: financing fish production in Nigeria - a review

    Ataguba, G.A.; Olowosegun, O.M.
    Microfinance refers to loans, savings, insurance, transfer services and other financial products targeted at low-income people. Artisanal fishing is a crucial source of livelihoods in developing nations, particularly for low-income families in rural areas where job options are limited. Nigeria depends heavily on revenues from natural resources, especially oil hence income from fishing is particularly important to Nigeria. Aquaculture is also being practiced with a growth rate that has increased over the years. Sources of funding for the operators of these sectors of the economy who are mostly poor peasants will ensure sustainable production and income generation. Informal microfinance groups...

  18. Species identification reveals mislabeling of important fish products in Iran by DNA barcoding

    Changizi, R.; Farahmand, H.; Soltani, M.; Asareh, R.; Ghiasvand, Z.
    This study reports on the molecular identification of fish species from processed products which had a priori been classified as belonging to 5 important species in Iran for human consumption. DNA barcoding using direct sequencing of an approximately 650bp of mitochondrial Cytochrome oxidase subunit I (COI) gene revealed incorrect labeling of Narrow-barred Spanish mackerel samples. High occurrence of fraudulent fishery products, if left unchecked, can pose a negative impact on the economy. This investigation adds further concern on the trading of processed fish products in Iran from both health and conservation points of view.

  19. Growth, mortality and yield per recruit of the king soldier bream Argyrops spinifer (Sparidae) from the Oman coast of the Arabian Sea

    Al-Kiyumi, F.; Mehanna, S.F.; Al-Kharusi, L.
    The King soldier bream Argyrops spinifer at Arabian Sea (Omani waters) was assessed using Beverton and Holt yield per recruit model. A total of 5520 specimens were collected during five trawl surveys between September 2007 and August 2008. The maximum life span was 11 years for length range of 11.0 – 62.1 cm TL. The von Bertalanffy growth parameters were K = 0.22 year^-1, L∞ = 65.51 cm, to = -0.75 year and W∞ = 5430g. The rates of total mortality Z, natural mortality M and fishing mortality F were 0.85, 0.26 and 0.59 year^-1 respectively. The exploitation ratio E...

  20. Bio-economic assessment of a purse seining at Orimedu fishing settlement off Lekki, Lagos State

    Abass, M.A.; Fakoya, K.A.; Akinwale, M.
    A bio- economic assessment based on the Return On Investment (ROI) of a single purse seiner was done from August 2007 to February 2008 at Orimedu. Catch composition in terms of relative abundance of species and their sizes were also assessed. Total income was derived from the product of average selling price for a basin of fish, average number of fish basins sampled from a purse seiner, number of fishing trips of a purse seiner per month and the total number of months. Total costs were derived from the sum of capital costs, operational costs, depreciation costs, maintenance cost and...

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