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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.
1

Predation as a mechanism for control of white perch : an investigation of food habits in two Nebraska reservoirs /

Gosch, Nathan J. C. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Nebraska--Lincoln, 2008. / Includes bibliographical references. Also available in PDF via the World Wide Web.
2

Site fidelity, home range, and daily movements of white perch, Morone americana, and striped bass, Morone saxatilis, in two small tributaries of the York River, Virginia/

McGrath, Patrick E., January 2005 (has links) (PDF)
Thesis (M.Sc.)--College of William and Mary. / Vita. Includes bibliographical references.
3

Trophic Dynamics and Cyanobacteria Blooms In Shallow Eutrophic Bays Of Lake Champlain

Gorney, Rebecca Michelle 01 January 2014 (has links)
This study was conducted to evaluate the relative roles of trophic dynamics and nutrient concentrations in the development of cyanobacteria blooms. The motivation for this research was to gain insights into how food webs respond to ecosystem-scale changes, using Lake Champlain as a case study. I sought to link field-based observations with experimentally derived data on mechanisms to better understand the processes that drive cyanobacteria blooms. My research addressed three specific topics: (1) associations among phytoplankton and nutrient concentration trends over time, (2) the impacts of planktivory by invasive fish on the ambient zooplankton community, and (3) the role of herbivore zooplankton grazers in determining the composition of the phytoplankton community. I found little evidence of a strong association between nutrient concentrations and phytoplankton community composition during summer months in shallow bays of Lake Champlain prone to annual cyanobacteria blooms. Fish diet analysis indicated that invasive white perch (Morone americana) and alewife (Alosa pseudoharengus) selectively graze on large zooplankton, which has likely led to substantial declines in zooplankton biomass. I used these results to inform the design of a mesocosm study, which tested the effects of zooplankton grazing on phytoplankton and provided support for the theory that large zooplankton grazing pressure changes the size structure, abundance and composition of phytoplankton. High nutrient concentrations support increased levels of ecosystem productivity, but cascading trophic dynamics are additional forces that are likely contributing to the determination of phytoplankton community composition. Collectively, my research suggests that in shallow bays of Lake Champlain, selective grazing by invasive planktivorous fish is shifting the size structure of the zooplankton grazer community and has likely contributed to conditions that favor dominance by cyanobacteria in summer.
4

Diet Analysis of Maumee River Fishes using Cytochrome C Oxidase (COI) DNA Metabarcoding ― Insights into a Critical Time of Year

Shortridge, Megan G., Shortridge 22 November 2016 (has links)
No description available.

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