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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Dusky dolphins in New Zealand group structure by sex and relatedness /

Shelton, Deborah Ellen, January 1900 (has links)
Thesis (M. S.)--Texas A&M University, 2006. / "Major Subject: Wildlife and Fisheries Sciences" Title from author supplied metadata (automated record created on Apr. 27, 2007.) Vita. Abstract. Includes bibliographical references.
412

Foraging ecology of wintering wading birds along the Gulf of Mexico coast

Sherry, Dawn Ann, January 1900 (has links)
Thesis (Ph. D.)--Texas A&M University, 2006. / "Major Subject: Wildlife and Fisheries Sciences" Title from author supplied metadata (automated record created on Apr. 27, 2007.) Vita. Abstract. Includes bibliographical references.
413

Comparative breeding ecology of Lesser Sandhill Cranes (Grus canadensis canadensis) and Siberian cranes (G. leucogeranus) in Eastern Siberia

Watanabe, Tsuyoshi, January 1900 (has links)
Thesis (Ph. D.)--Texas A&M University, 2006. / "Major Subject: Wildlife and Fisheries Sciences" Title from author supplied metadata (automated record created on Apr. 27, 2007.) Vita. Abstract. Includes bibliographical references.
414

Food web architecture in natural and impounded rivers of the Upper Paraná drainage basin, Brazil

Hoeinghaus, David Joseph, January 1900 (has links)
Thesis (Ph. D.)--Texas A&M University, 2006. / "Major Subject: Wildlife and Fisheries Sciences" Title from author supplied metadata (automated record created on Apr. 27, 2007.) Vita. Abstract. Includes bibliographical references.
415

Population Dynamics and Spatial Analysis of the Maine Green Sea Urchin (Strongylocentrotus droebachiensis) fishery

Grabowski, Robert C. January 2003 (has links) (PDF)
No description available.
416

Agent-Based Modeling with Classifier System: A New Modeling Tool to Investigate the Dynamics of Social/Ecological Systems with Particular Reference to the Maine Lobster Fishery

Yan, Liyin January 2007 (has links) (PDF)
No description available.
417

An agency for the common weal, the Newfoundland Board of Trade, 1909-1915

Hong, Robert G. January 1998 (has links) (PDF)
No description available.
418

Economic production from the coral reef fisheries of Jamaica and Captured Ecosystem Values

Gustavson, Kent Richard 27 October 2017 (has links)
The production of an economic good derived from a renewable natural resource base involves the extraction of ecosystem function values as represented by the contribution made to production by the originating ecosystem. The artisanal fisheries of Jamaica is used as a case study in the examination of the characteristics of economic production processes and the development of a biophysically-based index to account for captured ecosystem values. The following is provided: (i) a description of the fisheries of Jamaica and derivation of economic production function models; (ii) a description of the socio-economic condition of the fisheries of Montego Bay Marine Park (Montego Bay, Jamaica) which serves to further illustrate the nature of artisanal fisheries in Jamaica, as well as a more traditional economic approach to resource valuation; and, (iii) the development of an index which as a proxy measure captures the biophysical values of the contributions of the natural biotic environment (the “embodied ecosystem values”) to the fisheries, and an examination of the extent to which those values are proportionately reflected in monetary exchange values. In addition, contributions are made concerning: (i) the development of an economic data collection and analysis programme for Jamaica (also more widely applicable to countries of the developing tropics) which will allow for more informed decisions concerning the management of coral reef fisheries; (ii) general principles concerning the development of biophysical indices, such as indices of biodiversity, which will ultimately be used to inform government policy and management decisions; (iii) the validity of indices derived from ecosystem statistics; and, (iv) the potential for the further development of models which explicitly incorporate the contributions of ecosystems to economic production processes. Cobb-Douglas and translog models of fishing effort are derived from catch and effort data for the years 1996 and 1997 to describe the relationships between catch and firm-level inputs as they vary by fishery within Jamaica. Data on the total catch, crew size, gear soak time, and quantity of gear used yield separate functions of effort for the use of China net, trap, hand line, palanca, speargun, and troll fishing technologies. By further accounting for the month and fishing location (i.e. north coast versus south coast), the seasonal and regional influences on catch rates are explored. Patterns of production include reduced catch rates associated with fishing the north coast shelf and a seasonal peak in catch levels during the late summer and fall. The use of production function models of effort are found to provide informative descriptions of fishery production processes, yet avoid many of the technical difficulties associated with more traditional bioeconomic approaches. The Index of Captured Ecosystem Value (ICEV) is developed from a basis in information theory relevant to an analysis of network flows in ecosystems. Technical coefficients, describing the production relationship between ICEV values and market values of catches associated with individual fishing efforts, revealed that captured ecosystem function associated with fisheries using distinct technologies (i.e. China net, trap, hand line, palanca, and speargun) were valued differently by the market. This “surplus value” appears to be rooted in the observation that certain fisheries target species which are more connected within the coral reef food web than those species typically captured by other fisheries. Consideration of the biophysical contributions of coral reef ecosystems to fisheries production reveals distortions between market and supply-side values, indicating that the role of ecosystems is not being consistently treated. / Graduate
419

Chemoreception and feeding behaviour in whiting (Merlangius Merlangus L.) and cod (Gadus morhua L.)

Pawson, Michael G. January 1974 (has links)
No description available.
420

A comparative analysis of fish stock assessment methods: Spatial-temporal versus VPA.

Deng, Xiaoying. January 2000 (has links)
This thesis presents research on an alternative spatial-temporal method of fish stock assessment. We develop a simulation model of spatial-temporal stock analysis and compare its assessment with the common VPA/SPA method. In recent years, fisheries biologists have depended mainly on age structured aggregated sequential population analysis (SPA)/virtual population analysis (VPA) for stock assessment purposes. The VPA method is an aggregate model that consolidates all spatial and within-season temporal stock dynamics into a single total stock estimate. The proposed spatial-temporal method produces historical estimates of population size and fishing mortality rate by age and year. In this thesis, the abundance states of age-aggregated stock components are tracked in space over the course of each season using computer simulation. Data about fish stock spatial-temporal migration dynamics are used to estimate stock abundance in space and time over the course of a fishing season. The spatial-temporal assessment method is applied to the herring stock of the Scotia Fundy region of Atlantic Canada. The dynamics of the herring spawning groups are described and the simulation model is developed for a given season. The results suggest that disaggregated spatial-temporal estimates provide more information for in-season management of herring spawning groups than the traditional aggregate VPA approach.

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