Thesis--University of Basle. / Bibliography: p. 336-339.

Thesis (Ph. D. (Ichthyology & Fisheries Science))--Rhodes University, 2004.

Thesis (Ph. D. (Ichthyology & Fisheries Science))--Rhodes University, 2004.

Thesis (Ph. D.)--University of Western Australia, 2004. / Title from PDF title page (viewed on July 9, 2005). Includes bibliographical references (p. 166-182).

Thesis (Ph.D.)--Memorial University of Newfoundland, 1997. / Bibliography: leaves [366]-389.

During the period April 1994 and February 1996 as part of an investigation into the national Iinefishery, the east coast shore fishery and the recreational and commercial ski-boat fisheries were surveyed, at eight sites between Kei Mouth in the East and Stil Bay in the West. Roving creel, access point and aerial surveys were used. A questionnaire was developed for each sector to gather data on catch and effort, fisher demographics, economics, fisher attitudes towards, and knowledge of, the current management regulations and assess the efficacy of the fisheries inspectorate. During the access point survey the catch of 3273 fishers was inspected and 1556 interviews were conducted. Questionnaires were conducted on 118 recreational ski-boaters and the catch of 165 boats was inspected. 96 commercial skippers were interviewed and 230 had their catch inspected. Three aerial surveys of the entire area were conducted during which a total of 1067 shore fishers were counted giving a shore fisher density of 0.39 fishers.km⁻¹. The majority (99%) of participants in all sectors of the linefishery were male. The greatest number of participants were white, shore fishery 77% recreational ski-boat 98% commercial skiboat 89%, followed by coloured, asian and black people. To a large extent this reflects the income of various racial groups. Most fishers supported the current linefish management plan. However, when tested on their knowledge of the size limits, bag limits and closed seasons of their target species many shore fishers (59%) did not know them and a high proportion of fishers in all sectors had disobeyed at least one of the regulations (shore 50%, recreational ski-boat 70%, commercial ski-boat 56%). When compared to historical data the present catch per unit effort (CPUE) in all sectors has decreased. Most interviewees in the various sectors did not accept responsibility for the decline in CPUE, but attributed it to three principal reasons vis their perceived direct competitors, trawling and pollution. Analysis of the catch revealed that all sectors were multispecies fisheries, with each sector being characterised by a small number of target species. Catch composition differed significantly between the shore and ski-boat sectors, but there was significant overlap between the two skiboat sectors. Analysis of the catch in comparison to that reported to the National Marine Linefish System (NMLS) revealed that there was a substantial degree of under-reporting. There was little seasonal difference in effort in the shore fishery while the recreational ski-boat effort was highest in the summer and the commercial ski-boat effort was high in the winter. Effort in the shore and recreational ski-boat fisheries was concentrated over weekends while the commercial ski-boat effort was highest during weekdays. Total effort for the entire area was estimated at 903 186 (±1913) fisher days per annum in the shore fishery, 24 357 (±685) recreational ski-boat fisher days and 64 266 (±1686) commercial ski-boat fisher days. Expenditure and capital investment in the various sectors was calculated, as were earnings of the participants in the commercial ski-boat sector. The linefishery in the Eastern Cape was estimated to have a minimum capital investment in excess of R210 million and more than R32 million is spent annually on running costs. The commercial ski-boat fishery directly employed an estimated 3184 people. The economic implications of changes in CPUE for the commercial ski-boat fishery are considered, as are the benefits of a recreational angling licence. Management of the linefishery is discussed in relation to the findings of this study.

The South African demersal longline experiment is assessed with emphasis on the target species, kingklip Genypterus capensis. The hypothesis that kingklip on the South African coast comprise a unit stock is tested. Recommendations for the management of the fishery are made. Longlining was found to be commercially viable. Techniques have been developed to target on either kingklip or the Cape hakes, Herluccius capensis and H. paradoxus. Longline fishermen exploit the kingklip spawner stock from August to No v ember by taking advantage of prespawning aggregations on the South-East Coast . Effort switches to the West Coast in late summer and early winter where kingklip are less abundant and a larger proportion of hake is caught. Catch rates of kingklip on the South Coast have declined sharply and the resource there has been exploited at a rate greater than that required to retain 50% of the unexploited biomass . There is a 17,6% probability that the spawner biomass on the South Coast has already been depleted below its pristine level. On the West Coast the catch rates of kingklip are lower than on the South Coast and have not changed significantly, although within the 95% confidence limits there is a possibility that the resource there has also been depleted below 50% of its pristine level. Genypterus capensis on the South African coast comprise a unit stock. Comparison of kingklip morphology using multivariate and discriminant function analysis and of otolith morphology using univariate statistics shows that there are no significant differences between the fish on the West and South Coasts. They are a slow growing species and were aged up to 25 years. Kingklip on the West Coast are smaller and have a lower L~ than those on the South Coast, but this is not a characteristic of discrete stocks. Kingklip on the South Coast mature earlier than those on the West Coast and aggregate to spawn on the South - East Coast in spring. There is no obvious spawning period on the West Coast. It is hypothesized that kingklip spawning on the South-East Coast is in response to favourable environmental conditions that enhances the survival of their eggs and larvae. It is recommended that demersal longlining be established as a permanent kingklip-directed fishery but that effort should not be allowed to increase. The West and South Coasts should be managed .separately. A TAC of 5 OOOt for kingklip should be introduced for 1989 of which 2 OOOt should be allocated to the West Coast and 3 OOOt to the South Coast . A closed season for kingklip from 1 August to 30 September on the South-East Coast is recommended. Hake-directed longlining should not be allowed as its effect on the hake spawner stocks are unknown and could be a potential threat to the stability of the demersal trawl fishery.

This study examines the complex problems associated with the allocation and management of mobile salmon resources passing through politically partitioned land and sea space in southeastern Alaska and northern British Columbia. While the salmon fishing industry was found to be relatively important at the local level, it is suggested that the salmon of Canadian origin removed off Noyes Island "by Alaskan fishermen are not of critical importance to the economies of either Alaska or British Columbia when considered as a whole. Therefore, it is concluded that the Noyes Island conflict should not be allowed to jeopardize the salmon conservation programs of Canada and the United States by provoking a de facto abrogation of a mutually advantageous treaty designed to prevent the massive oceanic capture of salmon. From this case study in political geography it was determined that salmon fishing conflicts can best be understood by examining: (1) The peculiar nature of the salmon resource. (2) The state of knowledge concerning its origins and movements and the spatial implications of these movements. (3) The evolution of opposing national fisheries, (4) Interrelated political considerations. It was also found that salmon fishing conflicts could be classified into two categories based upon quantitative and ideological differences. Finally, a tentative geographic model was constructed that could serve as the basis for organizing future enquiry into salmon fishing disputes by clearly illustrating the spatial problems common to such conflicts. The model particularly emphasizes the lack of congruency between biotic and political units and the effects this has on competing, nationally organized exploitation of the salmon resource. / Arts, Faculty of / Geography, Department of / Graduate

This thesis presents a catch allocation model that was developed for J.S. McMillan Fisheries, Ltd. A linear program (LP) was developed to allocate chum salmon catches of variable size to a set of end products, where both the input salmon and output products are differentiated based on strict physical characteristics and quality requirements. The LP is designed to maximise the net profit of a catch subject to constraints on processing line capacity, market orders, and an upper boundary on production. A decision support tool was built around the LP model to facilitate user-directed reporting and updating of model parameters. The decision tool was shown to improve the structuring of the decision process, decrease the company's reliance on expert knowledge in making the catch allocation decision, as well as significantly decrease the time investment in the decision process. / Business, Sauder School of / Graduate

Zooplankton of the littoral and limnetic zones of Bear Lake, Idaho- Utah, were collected over a 17 -month period. Twenty-three species of zooplankton were recorded, as well as nine other species represented by both flora and fauna. At the time of sampling 17 physical and chemical parameters were a lso measured. Methods of analysis for the plankton and the environment are described and discussed. The objectives of this project were fourfold: To establish a record of the current zooplankton population before changes due to the increase o f organic nutrients occur. To compile a qualitative and quantitative standard against which future populations can be compared. To assess the source and the amount of present nutrients which are being contributed to the lake. To investigate the effect the present addition of nutrients is having on zooplankton productivity. The physical and chemical analysis of the Bear Lake waters showed a number of interesting trends. The measurement of total dissolved solids, when compared with previous investigations, showed a decline: i.e., it appears that a great dilution had taken place in the lake waters since 1912. The measurement of salinity revealed two chemical patterns in Bear Lake waters. First: chloride, sulfate, sodium, and potassium showed a decrease in concentration on a long-term basis. Second, calcium showed a slight rise with a leveling off, and magnesium showed a decline with a leveling off over the same period. Calcium is being precipitated as calcium carbonate, and the removal of sodium, potassium , sulfate, magnesium, and chloride is achieved through the pumping of lake waters outside the basin. Nitrogen was measured with respect to three of its forms--ammonia, nitrite, and nitrate. Ammonia was comparatively evenly distributed throughout the water column at all depths. The cycling of ammonia appeared to follow that of known oligotrophic lakes. Generally, the nitrite was low in the limnetic and allochthonous waters and higher in the littoral zone. The littoral and limnetic water exhibited lower nitrate levels than the allochthonous sources. This is believed to be due to the prevailing land use patterns. The production of cattle and sheep and the cultivation of extensively fertilized crops appear to give the most plausible answer. The littoral waters appeared to be higher with respect to ammonia, nitrite, and nitrate, in the microhabitats that are natural, and in others that are man-made: i.e., harbors, breakwaters, and shore based homes. The distribution of phosphate-phosphorous in the waters varied little during the study. The mean values were quite similar for the littoral and limnetic waters. The allochthonous waters had approximately four times the phosphate concentration of the lake waters. The chemical analysis of the bottom muds revealed that phosphorous as phosphate and as P2O5 were significantly higher in concentration between the 50- and 200-foot contours than at lesser depths. The low levels of soluble phosphate and the slight variation encountered in the water column seem to be related to the orthograde nature of the oxygen curve found in the lake. Relationships between chemical analysis and the zooplankton associated within a particular station in the lake were completed by correlation and regression analysis. Associations between independent and dependent variables apparently defined various environmental preferences or requirements necessary for the maintenance of particular individual species. In light of the basic taxonomic considerations these proposals appear to be within reason. Individual correlation and regression analysis were completed for three lake zones investigated: littoral, limnetic, and the haptobenthos. Individual analysis of variances were completed within the three Bear Lake zones in order to assess the affect of habitat on the plankton population. The statistical analyses were compared to the means for these several stations within one zone, and biological and statistical explanations were made. Supplementary water quality analyses were conducted in order to explain some abnormal chem1cal and biological results. Bacteriological testing of the Bear Lake waters revealed that a large percentage of the littoral and allied limnetic zone presented definite problems with respect to water quality and public use.