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Trent, L., Palko, B. J., & Trimble, A. (1987). Improved Method of Measuring Length of Large Samples of Fish (Vol. 49).
Zusammenfassung: A new method to record fish lengths is described. Its advantages include quick recording of large numbers of fish by one person, accurate measurements by inexperienced personnel, easy transmission of data, low expense, usability under harsh field conditions, and easy transportability.
Schlüsselwörter: Methode, fischerei
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Stamatopoulos, C., & Caddy, J. F. (1989). Estimation of von Bertalanffy growth parameters: A versatile linear regression approach (Vol. 45).
Zusammenfassung: A new linear regression method is presented for fitting the von Bertalanffy growth function to data on size at age, which is also applicable to tag and recapture data. From tests on simulated data the method shows lower error and bias and more flexibility of action than other commonly used methods.
Schlüsselwörter: Fischerei, statistik, modell, wachstum
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Tipping, J. M. (1994). Measuring fish by video image processing (Vol. 56).
Zusammenfassung: A microcomputer system that weighs and measures fish and records the data on a computer file was tested at two hatcheries. The device produced fairly accurate lengths and might save labor and reduce transcription errors.
Schlüsselwörter: hardware, fische, methode
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Pauly, D., Prein, M., & Hopkins, K. D. (1993). Multiple regression analysis of aquaculture experiments based on the “extended gulland-and-holt plot”: Model derivation, data requirements and recommended procedures.
Zusammenfassung: A method for the multivariate analysis of fish growth in aquaculture is presented. It is derived from a linearized version of the von Bertalanffy growth function (VBGF), which, in its original form, is a bivariate regression termed the Gulland-and-Holt plot. Here, a version in form of a multiple regression equation is presented. The “extended Gulland-and-Holt plot” permits to identify and quantify the key variables controlling fish growth and permits the inclusion of these environmental and treatment variables to explain variance in growth of fish. Von Bertalanffy growth parameters K and L sub( arrow left ) are obtained, which contain the combined environmental effects on fish growth and reflect the range of culture conditions. By computing the index of growth performance ( Phi '), the obtained regression models can be used for growth prediction and decisionmaking in fish farm management and production under a wide range of environmental and management conditions. Recommendations for the design of experiments, preparation of data for analysis and actual analysis procedures are given.
Schlüsselwörter: fish-culture; freshwater-aquaculture; Oreochromis-; multivariate-analysis
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Levin, J. Z. (1988). A rational parametric approach to latitude, longitude, and altitude (Vol. 35).
Zusammenfassung: A method for parametrically representing the surface of the earth is described. Latitude and longitude are replaced by parametric pseudolatitude and pseudolongitude. Conversions between Cartesian coordinates in three-space and the parametric form are described. A compact and precise algorithm for cartesian-to parametric form has been developed by way of tested computer procedures.
Schlüsselwörter: mapping-; map-projections; coordinate-systems; cartography-; latitude-; longitude-; height-
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Cole, R., Ward, F., Ward, T., Deitner, R., & Fiore, J. (1987). Model for optimization of socio-economic fishery values on the Rio Grande in New Mexico. New Mexico Water Resources Research Inst., Las Cruces (USA).
Zusammenfassung: A mathematical model which simulates sport-fish production yield and economic value in the Rio Grande basin of New Mexico is described. The model links hydrologic, biologic, and economic components into a mathematical representation of fisheries habitat, fishery dynamics, economic benefits, and income generated by sport-fishing in New Mexico. The model has a research version programmed in FORTRAN. The model users can modify water volume flowing through the basin by month, water stored in each reservoir, water discharged through connecting water material concentrations (suspended solids, total phosphorus, total nitrogen) in the water, site access, and site quality. (Prepared in cooperation with New Mexico State Univ., Las Cruces. Dept. of Fishery and Wildlife Sciences. Sponsored by Geological Survey, Reston, VA (USA). Water Resources Div.)
Schlüsselwörter: economic-models; sport-fishing; fishery-economics; USA,-New-Mexico,-Grande-R.-basin
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Ward, G., & Fitzgerald, G. J. (1987). Male aggression and female mate choice in the threespine stickleback, Gsterosteus aculeatus L..
Zusammenfassung: A laboratory study of female G. aculeatus revealed no conclusive evicence of active female mate choice on the basis of male aggression levels. However, highly aggressive males failed in 95% of all choice tests. The less aggressive ´chosen´ males where generally successful again in subsequent trials with the same female, and certain males were consistently successful with different females. Females exhibited an increased readiness to spawn at the end of the reproductive season, although the same males were usually selected again.
Schlüsselwörter: Sex, Fisch, Verhalten, Saison
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McGarvey, R. (1994). An age-structured open-access fishery model (Vol. 51).
Zusammenfassung: A dynamic model for open-access fisheries is presented. In addition to density dependence in recruitment and fishing effort changing in proportion to the level of profit fishermen earn which characterizes previous open-access models, it incorporates full age structure for the fish stock, lognormal environmental recruitment variability, and gear selectivity. The predator-prey cycling solution of the original Schaefer dynamic model, and subsequent open-access models, persists for these model extensions. Density dependence in recruitment induces greater global stability. Environmental recruitment variability, common in marine populations, is destabilizing in the neighborhood of the open-access equilibrium. Approximating model steady states of effort and catch by the corresponding averages from data time series underlies a new algorithm of parameter evaluation, applied here to an open-access model of the Georges Bank sea scallop (Placopecten magellanicus) fishery.
Schlüsselwörter: modell, statistik, population, dynamik, algorithmus
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McGarvey, R. (1994). An age-structured open-access fishery model (Vol. 51).
Zusammenfassung: A dynamic model for open-access fisheries is presented. In addition to density dependence in recruitment and fishing effort changing in proportion to the level of profit fishermen earn which characterizes previous open-access models, it incorporates full age structure for the fish stock, lognormal environmental recruitment variability, and gear selectivity. The predator-prey cycling solution of the original Schaefer dynamic model, and subsequent open-access models, persists for these model extensions. Density dependence in recruitment induces greater global stability. Environmental recruitment variability, common in marine populations, is destabilizing in the neighborhood of the open-access equilibrium. Approximating model steady states of effort and catch by the corresponding averages from data time series underlies a new algorithm of parameter evaluation, applied here to an open-access model of the Georges Bank sea scallop (Placopecten magellanicus) fishery.
Schlüsselwörter: fischerei, Population, Mathematik, Modell, Statistik, CPUE
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Dahlberg, M. L. (1978). Computer program for analysis of the homogeneity and goodness of fit of frequency distributions, FORTRAN 4 (Vol. 76).
Zusammenfassung: A computer program was developed which forms frequency distributions from length measurements and then calculates a chi-square statistic which is used to test the homogeneity of the frequencies for the purpose of pooling. Output includes listing of arithmetic mean, variance, standard deviation, standard error of the mean, total sample size, and chi-square statistic of goodness of fit for individual groups and for the pooled frequency distribution. Histograms of all frequency distributions are produced as full-page printer charts, scaled if necessary to 50 units by up to 100 class intervals. The pooled frequencies and class midpoints are punched on cards to facilitate additional analyses. The program was developed on an IBM 360/65 OS System and required 56,811 bytes of storage.
Schlüsselwörter: computer-programmes; population-structure
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