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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.
161

Population dynamics of eastern grey kangaroos in temperate grasslands

Fletcher, Don January 2006 (has links)
Thesis (Ph. D.)--University of Canberra, 2006. / Title from PDF title page (viewed on Dec. 11, 2007). Includes bibliographical references (p. 247-290).
162

Culverts as potential barriers to fish movement

Haughey, Joanne Lee. January 2007 (has links)
Thesis (M.E.S.)--University of Delaware, 2007. / Principal faculty advisor: Clifford Keil, Dept. of Entomology & Wildlife Ecology. Includes bibliographical references.
163

Migratory connectivity in white-throated sparrows : inferences from stable hydrogen isotope analyses

Mazerolle, Daniel Freddy 15 August 2005
Tracking migratory movements of birds between breeding and wintering areas is important for both theoretical and conservation purposes. In particular, information about linkages between stages of the annual cycle (i.e., migratory connectivity) is essential for identifying factors and processes limiting population sizes of birds. Further, this information is necessary for testing assumptions and hypotheses about the evolution of avian migratory patterns. Here, I used stable hydrogen isotope (δD) analyses of tissues representing different periods and geographic regions of the annual cycle of white-throated sparrows, Zonotrichia albicollis, to provide new information on spatial and temporal linkages between stages of the annual cycle of this species. To achieve this objective, I sampled white-throated sparrows during spring and fall migration of 2002 and 2003 at a key staging ground for North American migratory birds located at Delta Marsh, Manitoba. Based on evaluations of the correspondence between δD values of feathers, claws, and cellular portions of blood of migrants, I determined that δD values of claws and blood cells were not suitable for estimating wintering origins of individuals captured en route to breeding areas. However, δD values of head feathers grown on wintering areas and tail feathers grown on breeding areas corresponded to values expected for feathers grown in broad areas within the wintering and breeding range of the species, respectively. The δD values of feathers showed no relationship between estimated breeding or natal and wintering latitudes of white-throated sparrows. However, band-encounter analyses indicated a clear eastwest segregation of populations across Canada, a finding that suggests that this species has a parallel migration system. Temporally, all components of the breeding populations migrated together during spring migration. However, as expected, white-throated sparrows exhibited sex-biased differential timing of spring arrival and latitude of wintering origin. Consistent with several other differential migrants, female white-throated sparrows arrived later and originated from more southern latitudes. There was also a negative relationship between wintering latitude and arrival dates of individuals during the second spring of the study. The existence of this relationship is a key assumption of differential migration hypotheses that had not been previously validated. Furthermore, since timing of arrival at breeding areas is critical to establishing high-quality territories and pair bonds, relationships between wintering latitude and arrival date of individuals could have important carry-over effects to reproduction. Based on standard body condition indices, white-throated sparrows migrating longer distances to reach breeding areas were not in poorer body condition than those migrating shorter distances. Thus, the cost of migrating longer distances does not appear to affect pre-breeding body condition, a parameter known to be linked with reproductive success.
164

Migratory connectivity in white-throated sparrows : inferences from stable hydrogen isotope analyses

Mazerolle, Daniel Freddy 15 August 2005 (has links)
Tracking migratory movements of birds between breeding and wintering areas is important for both theoretical and conservation purposes. In particular, information about linkages between stages of the annual cycle (i.e., migratory connectivity) is essential for identifying factors and processes limiting population sizes of birds. Further, this information is necessary for testing assumptions and hypotheses about the evolution of avian migratory patterns. Here, I used stable hydrogen isotope (δD) analyses of tissues representing different periods and geographic regions of the annual cycle of white-throated sparrows, Zonotrichia albicollis, to provide new information on spatial and temporal linkages between stages of the annual cycle of this species. To achieve this objective, I sampled white-throated sparrows during spring and fall migration of 2002 and 2003 at a key staging ground for North American migratory birds located at Delta Marsh, Manitoba. Based on evaluations of the correspondence between δD values of feathers, claws, and cellular portions of blood of migrants, I determined that δD values of claws and blood cells were not suitable for estimating wintering origins of individuals captured en route to breeding areas. However, δD values of head feathers grown on wintering areas and tail feathers grown on breeding areas corresponded to values expected for feathers grown in broad areas within the wintering and breeding range of the species, respectively. The δD values of feathers showed no relationship between estimated breeding or natal and wintering latitudes of white-throated sparrows. However, band-encounter analyses indicated a clear eastwest segregation of populations across Canada, a finding that suggests that this species has a parallel migration system. Temporally, all components of the breeding populations migrated together during spring migration. However, as expected, white-throated sparrows exhibited sex-biased differential timing of spring arrival and latitude of wintering origin. Consistent with several other differential migrants, female white-throated sparrows arrived later and originated from more southern latitudes. There was also a negative relationship between wintering latitude and arrival dates of individuals during the second spring of the study. The existence of this relationship is a key assumption of differential migration hypotheses that had not been previously validated. Furthermore, since timing of arrival at breeding areas is critical to establishing high-quality territories and pair bonds, relationships between wintering latitude and arrival date of individuals could have important carry-over effects to reproduction. Based on standard body condition indices, white-throated sparrows migrating longer distances to reach breeding areas were not in poorer body condition than those migrating shorter distances. Thus, the cost of migrating longer distances does not appear to affect pre-breeding body condition, a parameter known to be linked with reproductive success.
165

Spatial population dynamics of recolonizing wolves in the western Alps

Marucco, Francesca. January 2009 (has links)
Thesis (PHD)--University of Montana, 2009. / Contents viewed on December 22, 2009. Title from author supplied metadata. Includes bibliographical references.
166

Biodiversity and fear ecology the cascading effects of species richness and nontrophic interactions /

Steffan, Shawn Alan. January 2009 (has links) (PDF)
Thesis (Ph. D.)--Washington State University, May 2009. / Title from PDF title page (viewed on Feb. 12, 2010). "Department of Entomology." Includes bibliographical references.
167

Spatial ecology of bacteria in surficial marine sediments /

Schmidt, Jill Lisa. January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 132-152).
168

Factors controlling alewife (Alosa psuedoharengus) population abundance among four rivers in mid-coast Maine /

Spencer, Erin Elizabeth, January 2009 (has links)
Thesis (M.S.) in Marine Biology--University of Maine, 2009. / Includes vita. Includes bibliographical references (leaves 44-48).
169

Crayfish (Procambarus spp.) response to hydrologic restoration of the Florida Everglades /

Hendrix, Albert Noble. January 2003 (has links)
Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 133-144).
170

An investigation on length-based models used in quantitative population modeling /

Ernst, Billy, January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (leaves 132-145).

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