Thesis (M.S.)--Michigan State University. Dept. of Fisheries and Wildlife, 2008. / Title from PDF t.p. (viewed on Aug. 7, 2009) Includes bibliographical references (p. 62-64). Also issued in print.

Thesis (M. M. S.)--Memorial University of Newfoundland, 1999. / Bibliography: leaves 84-90.

No description available.

published_or_final_version / abstract / Biological Sciences / Master / Master of Philosophy

Carp aquaculture in South Asia suffers severely from a lack of genetic management, which has eroded the genetic quality of both captive and wild populations. Use of molecular markers, especially microsatellites, has revolutionized genetic management of hatchery stocks through its ability to detect kinship between individuals and hence in controlling level of inbreeding and loss of genetic diversity. In the present PhD work, microsatellite markers were applied to breeding programmes for silver carp (Hypophthalmichthys molitrix) and common carp (Cyprinus carpio) to study different genetic management aspects and new markers were generated from rohu (Labeo rohita). A set of newly isolated microsatellite markers from silver carp were characterized and two pentaplex PCR reactions were optimized to enable rapid genotyping of large number of individuals at 10 microsatellite loci. The utility of these markers in parentage, sibship and relatedness analysis were assessed by applying them to groups of fish with known relationship. These markers were used for parentage analysis in a breeding programme designed to estimate heritability of harvest weight and length in silver carp. Full- and half-sib families were created in three sets of partly factorial mating and all the families from each set were reared in communal ponds from very early life stages. With ten microsatellites 96.3% of the offspring could be assigned to a single family. Heritability estimates were found to be 0.65 ± 0.13 for weight and 0.50 ± 0.13 for length. High estimates of h2 suggested that this population should respond rapidly to selection for increased harvest size. Microsatellite markers were also applied to monitor the early stages of a mass selection programme in common carp (Cyprinus carpio). The selection was initiated from a base population synthesized from six different stocks. The selected individuals were divided to create two separate lines. The aims of this study were to monitor whether the stocks were represented in the intended proportions in the F1 selected populations, to investigate the relative contribution of families and its impact on effective population size and to identify any loss of molecular genetic variation. Five highly polymorphic microsatellites were used for parentage analysis of the selected fish to track stock and family contribution. Overall, large perturbations were observed in the relative contributions of two major stocks. Family contribution was also highly variable, causing the Ne to drop to below half the census size. A loss of 6.9%-12.2% of microsatellite alleles was observed but loss of heterozygosity was not very prominent. The replicate lines showed significant differences in allelic distribution after the first generation of selection, but not in genotypic distribution. Finally, 52 microsatellite markers were isolated from a partial genomic library of rohu using a selective hybridization protocol. Characterization of these markers resulted in 36 polymorphic loci, which will be useful in future work on conservation and management of both wild and captive rohu populations.

The Sultanate of Oman has 1700 km of coastline extending from the Arabian Gulf south to the Arabian Sea. The demersal fish distributions and assemblages have not previously been well defined. In winter, variations in the oceanography of the area are minimal. In summer, however, the Arabian Sea is strongly influenced by the southwest monsoon. For this study the continental shelf off Oman was divided into eight regional areas and research trawl data on the distribution of demersal fish assemblages was studied using two forms of multivariate statistical analysis: two-way indicator species analysis and detrended correspondence analysis. The study was carried out to examine the influence on the species assemblages of geographical zonation, seasonal variation, and factors such as depth, time of day, and distance from untrawlable ground. There was seasonal variation in the fish assemblages and this variation was greatly influenced by the summer monsoon. Within each regional area depth appeared to be the major factor determining species distribution. In addition to the multivariate analyses, univariate techniques were applied to the catch rate data for forty commercial species to study in detail the influence of time of day and distance from untrawlable ground, factors which could potentially influence stock assessment estimates of fish biomass. Because the data were highly unbalanced, they were analyzed using General Linear Model with five factors, two continuous variables, and ten interaction terms to examine variation in the log-transformed catch rates. The factors time of day and distance from untrawlable ground, in combination with other factors, had significant effects on the catch rates for half of the species. / Graduation date: 1995

This research includes investigations of the ocean water quality of Tainan, its contamination sources and examines its relations to the fishing industry. It also explores the connection between topographical changes and evolution of the Tainan fishing industry and by using relevant information of ocean weather, tidal waves, wind speed, wind direction, and typhoon to study its relatedness to the developments of the fishing industry. It will further look at the role of the government in pollution prevention measures of the ocean, which specific laws and regulations must be setup and put into motion, so it can have a key role and have authoritative power. The quality of the marine environment has obviously deteriorated as the economy developed, and public hazard signals should become a severe issue that the government should face. Marine biological resources are common assets of the humankind and it is closely related to human survival, therefore, marine ecosystem must be properly preserved so it can maintain its most natural state and its resources can be sustained for our next generation to enjoy. The conclusions of this research includes suggestions for planning marine contamination report system and advice the government to set up an award system to encourage local coastal residents and fishermen to establish marine patrol volunteer organizations and report immediately if they discover any oil contamination in the ocean. Also, to target the characteristic of fishing industry depending on natural resources, it offers a suggested direction for important policies of reinforcing environmental protection and resource preservation and recommends putting in as much protective reef as possible within 3 nautical miles, which are designed to stop trawling nets but does not damage fishing gears. It also advocates waste reduction and reuse of recycled items and by following the treatment method for sewage, if we can transform wastes into usable resources and naturally reduce the pressure of further treatments, the proper handling for marine wastes should be cautiously designed in order to directly and effectively resolve the problem of large amount of wastes. It calls upon the government to appropriately develop, use, and sustainably manage the rich marine resources that we possess. In addition to reinforcing marine-related laws and regulations (amendment), it also aims to strengthen the protection and management of marine territory, actively engage in related research and development of marine resource use to enhance the development of our nation¡¦s marine resources, the technology, and its standards. Finally, by investigating from a sustainable use of the ocean point of view, it is possible to explore new directions for the future developments of the fishing industry and propose possible development strategies, and by examining the current condition of Tainan's coastal fisheries resources, it offers relevant resource management plans for industry-related management units and businesses to take into consideration. Our nation has the ability and conditions to develop marine industry and under the demands of international competition and domestic development, a continuation for the marine industry development is of absolute importance and necessity.

Diss. (sammanfattning) Göteborg : Univ., 2005. / Härtill 3 uppsatser.

ln this study the exploitation of the fish fauna of the Kosi estuarine system by man and natural predators is described and estimates made of the off-take and its species composition. The most important human exploitation, that by the traditional Zulu fish traps, was monitored over a four year period and the data collected were used to give an insight into the marine fish populations of the system. All the physical parameters, which it was thought could influence the migrations of fish, were monitored and correlations between these and the daily and monthly fish trap catches were used to interpret fish movements into and out of the system. Reasons for the annual migrations and day to day movements of fish were investigated. In order to establish relative off-takes by local fishermen and sport anglers fish were tagged inside the system and the recovery rates by the various fishing methods were used to calculate estimates of the percentage off-takes of these principal human exploitation methods. These data were also used to obtain estimates of the population sizes of the major marine fish species inside the system. Catch data were used to indicate the levels of estuarine dependence of these species. Where possible comparable data from other areas were used to indicate whether or not similar trends in catch abundance were obvious. The ecological and economic importance of the Kosi system is discussed and its value to the local inhabitants stressed. Competition between the various fishing techniques is described and recommendations are made concerning future fish exploitation. Natural predation rates are also discussed and levels compared with those of other systems. The fish food resources of the systems are considered in the light of recently declining salinities, destruction of swamp forests and increasing numbers of hippopotami. The implications of these changing factors are discussed as is their impact on the Kosi Bay fisheries. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1986.

Thesis (Ph. D.)--University of Hawaii at Manoa, 1995. / Includes bibliographical references (leaves 265-284). / Microfiche. / xxv, 284 leaves, bound ill., maps 29 cm