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Akamine, T. (1990). An interval estimation of Leslie's method in removal methods.
Zusammenfassung: Leslie's method in removal methods is modeled into the joint of the binomial distributions. An interval estimation of p (removal ratio) and n (initial population size) based on the null hypothesis for p and n is easily obtained by the approximation of each binomial distribution to the normal distribution. The confidence region on the (p, n) plane is easily obtained by micro-computers. The maximum likelihood method for a point estimation and the convenient method on the curves of partial maximum likelihood for an interval estimation are also presented.
Schlüsselwörter: Fisch, statistik, binominal, population, basic, listing, modell, methode
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Magnusson, K. G. (1995). An overview of the multispecies VPA -- theory and applications (Vol. 5).
Zusammenfassung: Multispecies virtual population analysis is an attempt to take species interactions into account when assessing the status of fish stocks. It was introduced primarily with the aim of lowering the uncertainty in the natural mortality rate as used in single species VPA and to take account of variability between years and ages by calculating inside the model the part of the mortality rate caused by predation. The output of the MSVPA is therefore – in addition to stock sizes and fishing mortality rates as in single species VPA and intraspecific – and possible species replacement are not considered and neither is predation on larvae and prerecruits. The potential relevance of multispecies models lies in long-term forecasts since short-term forecasts from multi- and single species models differ only slightly. In making long-term forecasts, predicting recruitment is of fundamental importance and the value of MSVPA in throwing light on the processes governing recruitment is limited. MSVPA is concerned primarily with calculating postrecruitment mortalities, and although in principle there is nothing to prevent prerecruitment predation mortalities being calculated, such estimates are not likely to be reliable or useful. Predation on the larval stages can be of major importance in determining recruitment but is not addressed in the MSVPA. Thus, it is quite possible that processes which are not dealt with in the MSVPA are much more important in determining the future of the fisheries. In view of all this uncertainty, it is inevitable that it will be questioned whether multispecies management advice is superior to single species advice.
Schlüsselwörter: vpa, statistik, modell, vergleich, fischerei
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Juell, J. E., & Westerberg, H. (1993). An ultrasonic telemetric system for automatic positioning of individual fish used to track Atlantic salmon (Salmo salar L.) in a sea cage (Vol. 12).
Zusammenfassung: A telemetric system for automatic positioning of individual fish in the vertical or horizontal plane is described. The position of a transmitter in a fish is computed from the difference in arrival time of the ultrasonic signal to a fixed array of hydrophones. Sources of error in positioning are discussed. In a preliminary study, the resolution of the system in time and space was adequate to monitor the behaviour of adult salmon in a sea cage. At moderate stocking density the salmon was swimming continually in counter-clockwise circles and diel rhythms in swimming speed, depth and path-radius were observed. With only 30 fish in the cage this stereotype behaviour broke down. Few or no visits into the feeding area during some feedings indicated a variable feeding motivation.
Schlüsselwörter: telemetrie, fische, methode, technik
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Hoenig, J. M., Morgan, M. J., & Brown, C. A. (1995). Analysing differences between two age determination methods by tests of symmetry (Vol. 52).
Zusammenfassung: A common problem in fisheries science is the comparison of two methods for obtaining ages of individual animals. The authors suggest that if the overall level of agreement is low between two ageing methods used on the same sample of fish, then one can use a test of symmetry to look for evidence of systematic disagreement. A chi super(2) test is used to determine if the number of fish assigned age i from method 1 and age j from method 2 differs significantly from the number of fish assigned age j from method 1 and age i from method 2. Such a test can also be used to determine the range of nominal ages over which two methods appear to give comparable results.
Schlüsselwörter: Altersbestimmung, Fischerei, Statistik, Methode
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Green, P. E. J., & Macdonald, P. D. M. (1987). Analysis of Mark-Recapture Data from Hatchery-Raised Salmon Using Log-Linear Models (Vol. 44).
Schlüsselwörter: Capt-recapt, fischerei, methode, statistik, modell
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Törlitz, H. (1922). Anatomische und entwicklungsgeschichtliche Beiträge zur Artfrage unseres Flußalles (Vol. 21).
Schlüsselwörter: Verbreitung, Systematik
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Harsanyi, A. (1996). Angelfischereiliche Nutzung von Gewässern (Vol. 10).
Schlüsselwörter: Fisch, Fischerei, Angeln, Nutzung
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Knösche, R. (1996). Anmerkungen zur Hechtwirtschaft in Seen (Vol. 1996).
Schlüsselwörter: Fisch, Hecht, Esox lucius, Fischerei, See,
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Dyk, V. (1965). Anpassungsbreite bei der Goldorfe und bei dem Moderlieschen (Vol. 13 NF).
Schlüsselwörter: Verhaltensforschung
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Zink, R. (1989). ANSI, die zweite.
Schlüsselwörter: Tastatur, methode
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