Thesis (PhD--Geography)--University of Auckland, 2010. / " A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Marine Science." Includes bibliographical references (p. 337-355).

A model of a fishery with an uncertain fish stock is proposed to compare alternative management systems with individual transferable quotas (ITQs). Assumptions of the model include: (1) the fish stock fluctuates randomly year by year; (2) in-season stock depletion is small; (3) the total allowable catch (TAC) set by the quota authorities has a definite relation with the fish stock level; (4) the true value of the stock level is revealed only at the middle of each season, when the authorities revise the TAC; (5) fishers form rational expectations on future quota prices. The principal results are: (a) If fishers are risk-neutral, the share quota (SQ) system and the quantity quota (QQ) system generate the same amount of fishery rent, although the division of the rent between fishers and the authorities under one system is different from the other. If the TAC is proportional to the stock level, the more price-inelastic the demand for fish is, the more likely it is that fishers are better off under the QQ system at the expense of the authorities. (b) A quota tax and a harvest tax that collect the same amount of revenue for the authorities result in the same division of the fishery rent among heterogeneous fishers. The quota tax and the profit tax differ in this respect. Which fishers will prefer a quota tax over a profit tax will depend on fishers' shares of the initial quota endowment and in total inframarginal profits afterward. (c) If fishers are risk-averse, the SQ system and the QQ system are not equivalent in their allocative efficiency. An example shows that the SQ system is potentially better than the QQ system when fishers prefer the latter and the authorities prefer the former. This conclusion has to be modified if risk-neutral traders participate in the quota market / Arts, Faculty of / Vancouver School of Economics / Graduate

The thesis consists of four papers that deal with the development of a biologically reasonable role for protein alleles in fisheries management. Paper 1: The need for an understanding of the biological properties of protein alleles is established by arguments that the neutral theory of alleliccvariation is an effective null hypothesis to the Fisher/Haldane/Wright definition of selection, but not a legitimate explanation for allelic variation in its own right. The literature demonstrating physiological differences between alleles in fish is reviewed. General biochemical and various ecological arguments are put forward to support the empirical evidence for significant physiological differences between alleles. The three main empirical arguments of neutral theorists, the segregational load argument, the molecular clock analogy, and the correlation between polymorphism and the molecular weight of proteins, have had a great influence on practical analysis and experimental design of fisheries management experiments in allele frequency. The validity of these empirical arguments is questioned. Statistical problems associated with the neutralist usage of allelic variation in fisheries management are briefly reviewed. Paper 2: Transferrin alleles are widely used in fisheries management as neutral markers. The biological role of transferrin alleles is reviewed and the effects of the biological properties and the statistical use of transferrin variants are discussed. Paper 3: The biological role of alleles requires some relationship between allelic variants and the parameters of fisheries management models before allelic variation can be assigned a practical role in fisheries management. Such a relationship is demonstrated between allelic genotypes at the phosphoglucomutase locus in liver and growth in the fish Cheilodactylus macropterus. Arguments are also presented for a significant change in allele frequency in this species due to fishing pressure. Paper 4: A biological role of alleles in fisheries management that is based on physiological differences between alleles may require an extensive understanding of the physiology and biochemistry of the fish before the allelic variation can be put to any practical use. Experimental data are presented to show that the metals Fe, Zn, P, Sr, and Na in the fish otolith reflect the ambient temperature. Thus an individual temperature life-history of a fish may be found in the otolith providing one, of the important experimental parameters necessary to understanding the biochemical and physiological role of allelic variants. The thesis concludes with a brief and general overview of fisheries management models and the reasons why the biological role of allelic variation is pertinent to these models. / Arts, Faculty of / Sociology, Department of / Graduate

No description available.

No description available.

Fish populations from four borrow pit lakes were evaluated for growth, condition, and composition. Information obtained from this study was used to formulate management possibilities to improve the sport fishery in these lakes. This study was conducted on four borrow pit lakes in Delaware and Grant Counties along Interstate 69 in eastcentral Indiana from April, 1976 to October, 1976.Growth data revealed that largemouth bass from Cardinal, Dumpert's, and Walter's Lakes did not reach harvestable size (12 in.) until they were 4 or 5 years old. Bass from all three lakes averaged approximately 62 mm for the yearly increment of growth. Bluegill from Cardinal and Walter's Lakes reached harvestable size (5 in.) by age four while bluegill from Dumpert's Lake were 3 years old when they reached harvestable size. Bluegill averaged 26 mm and 28 mm respectively for Cardinal and Walter's Lakes while Dumpert's Lake averaged 42 mm for the yearly increment.Condition data revealed that only the age five bluegill from Dumpert's Lake were classified in good condition. There were no largemouth bass classified in good condition whereas only age five through seven bass in Walter's Lake were classified in average condition.Growth rates for bass and bluegill were less than most values given in the literature with Dumpert's Lake having the fastest growing bass and bluegill. Bluegill was the dominant species captured from all lakes except Cardinal Lake where gizzard shad was the dominant species. Bluegill and largemouth bass averaged 65% and 12% of the population respectively when young-of-the-year fish were included. This study revealed that these lakes should be able to support a warm-water sport fishery with proper management techniques.

Co-management is considered an alternative approach to fisheries management, however, not all co-managed fisheries have been successful. Most studies discussing the success and failure of co-management have emphasized economic and social attributes of success and failure, such as fishery rights and institutional arrangements. The effect on co-management of biological characteristics, such as the growth rate of the fish stock and the stock size, has gained little attention. This study investigates the influence of intrinsic growth rate (r) and relative stock size (B') on fishers' decision to cooperate with catch quotas. The concept of mixed strategies from game theory is incorporated with basic economic concepts and a biomass dynamics model to capture important aspects in a fishery cooperative. The discounting concept is applied to capture the fishers' tendency to cooperate (��[subscript i]). Profits from fishing are specified for each fisher within a 2 by 2 matrix with two players and two strategies (cooperative and non-cooperative). When both players have dominant strategies, where one player's best strategy coincides with the other player's best strategy, the game has a pure strategy equilibrium. Alternatively, the equilibrium outcome of the game is determined using mixed strategies. The results indicate that the biological parameters, r and B', influence fishers' cooperation. However, social parameters (��[subscript i]) and economic parameters (profit/cost ratio when the stock is at the carrying capacity) must also be considered. Furthermore, this study finds that the fishers are more likely to play the cooperative strategy over very wide ranges of r and B' when their tendencies to cooperate are high. In contrast, the fishers are more likely to play mixed strategy when their tendencies to cooperate are low. Having a large discrepancy between the fishers' tendencies to cooperate has less influence on the outcomes of the game than having high values for the fishers' tendencies to cooperate. The profit/cost ratio generally accentuates the most frequent outcomes of the game. For instance, if the outcomes are mostly mixed strategies, a higher ratio expands the mixed strategy outcomes over wider ranges of r and B'. / Graduation date: 2001

Thesis (Ph.D.)--University of Washington, 2001. / Chairperson: James W. Harrington. Includes bibliographical references.

Thesis (M.S.)--University of California, Santa Cruz, 2003. / Includes bibliographical references (leaves 71-77)

Thesis (Ph. D.)--University of Delaware, 1996. / Includes bibliographical references (p. 107-119).