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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.
11

A computational study of the effects of temperature variation on turtle egg development, sex determination, and population dynamics

Parrott, Amy. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed July 6, 2010). PDF text: ix, 103 p. : ill. (some col.) ; 2 Mb. UMI publication number: AAT 3365844. Includes bibliographical references. Also available in microfilm and microfiche formats.
12

Isolation and identification of the fecal pollution indicators Enterococcus spp. from seagrass Thalassia testudinum at La Parguera, Puerto Rico and the use of Enterococci for microbial source tracking /

Rivera-Torres, Yaritza. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Puerto Rico, Mayagüez Campus, 2008. / Tables. Printout. Includes bibliographical references (leaves 64-70).
13

Factors affecting population dynamics of eastern pacific leatherback turtles (Dermochelys coriacea) /

Tomillo, Maria del Pilar Santidrián. Spotila, James R., January 2007 (has links)
Thesis (Ph.D.)--Drexel University, 2007. / Includes abstract and vita. Includes bibliographical references (leaves 104-115).
14

Conservational implications of temperature-dependent sex determination

Therrien, Corie L. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2008. / Description based on contents viewed Feb. 15, 2009; title from PDF t.p. Includes bibliographical references.
15

Nest site characteristics of the Western Pond Turtle, Clemmys marmorata, at Fern Ridge Reservoir, in West Central Oregon /

Holte, Deborah Lyn. January 1998 (has links)
Thesis (M.S.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references (leaves 102-106). Also available online.
16

Establishment and Growth of a Sea Turtle Rookery the Population Biology of the Leatherback in Florida

Stewart, Kelly Rhoda, January 2007 (has links)
Thesis (Ph. D.)--Duke University, 2007. / Includes bibliographical references.
17

A comparison of western pond turtle (Actinemys marmorata) movements in perennial and intermittent portions of a Northwestern California river system /

Bondi, Cheryl A. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 65-69). Also available via Humboldt Digital Scholar.
18

Plasma levels of vitamins A and E in marine turtles (Chelonia mydas and Caretta caretta)

Frutchey, Karen Patricia 01 January 2004 (has links) (PDF)
Insight into blood values for free-ranging populations of chelonians is very incomplete. A better understanding of marine turtle ecological physiology is necessary for population health assessments and conservation management plans. Vitamins A and E are fat-soluble compounds required by vertebrates. Vitamin A is required for growth, differentiation and integrity of epithelial tissue, bone remodeling, reproduction and vision. Vitamin E is a constituent of cell membranes where it is an antioxidant and free radical scavenger. Both nutrients are required for reproduction and immune system function. I determined concentrations of vitamins A and E in plasma of blood samples from Caretta caretta and Chelonia mydas using high performance liquid chromatography (HPLC). The first investigation focused on vitamin concentrations in nesting Caretta caretta and Chelonia mydas in the Archie Carr National Wildlife Refuge, Melbourne Beach, Florida, USA. Vitamin A concentrations were significantly higher in the herbivore, Chelonia than in the carnivore, Caretta. Plasma vitamin A concentrations decreased in Caretta as the nesting season progressed, while they remained constant in Chelonia. Plasma vitamin A concentrations only decline after liver stores of the vitamin are depleted, so it appears Caretta did not feed during the nesting season. Plasma vitamin concentrations in Chelonia remained stable during the nesting season, so it is not clear whether green turtles fed or fasted as the season progressed. Plasma vitamin E concentrations were significantly higher in Caretta than in Chelonia. This suggests that marine turtles follow the previously established chelonian pattern of carnivores having greater circulating concentrations of vitamin Ethan herbivores. The second study focused on vitamin concentrations in subadult Caretta and juvenile Chelonia from three Atlantic coastal habitats: Indian River Lagoon (IRL), the Nearshore Reef and Trident Submarine Basin. The disease fibropapillomatosis (FP) is prevalent in turtles from the IRL and the Nearshore Reef but not Trident Submarine Basin. Vitamin E concentrations differed significantly among turtles with different degrees of FP affliction. Turtles moderately afflicted with had significantly lower plasma concentrations of vitamin E compared with turtles not afflicted with the disease and as a result, may have compromised immune status. In contrast, however, severely afflicted turtles did not have lower circulating levels of vitamin E compared with those of mildly afflicted turtles. Vitamin A varied significantly among Chelonia from the three different developmental habitats. Turtles from the IRL had significantly higher concentrations of circulating vitamin A than turtles from both the Reef and Trident Basin. Chelonia on the Reef had significantly higher circulating concentrations of vitamin E than turtles in Trident Basin. Chelonia in the IRL had vitamin E concentrations that did not differ significantly from either the Nearshore Reef or Trident Basin turtles. Plasma vitamin E concentrations increased with decreasing straight-line carapace length in Chelonia. This is one of the largest scale vitamin studies conducted on reptiles and will contribute to conservation of marine turtles by providing baseline data on vitamins A and E. This information is useful for wildlife rehabilitators and zoos and aquaria with captive marine turtles. Effects of reproduction and disease on plasma concentrations of vitamins A and E are also discussed in this thesis.
19

The cranial morphology of fossil and living sea turtles (Cheloniidae, Dermochelyidae and Desmarochelyidae)

Smith, Donald Thomas Jeremy January 1989 (has links)
Many of the early taxonomic studies of fossil sea turtles relied heavily on postcranial evidence. Both the Cheloniidae and Dermochelyidae were erected on detail of the shell and limbs. ‘Desmatochelys’ was originally described in part using cranial evidence, but later workers (Zangerl and Sloan, 1960) suppressed the family on evidence from the shell. Little in the way of comparative work has been undertaken using the cranial morphology of fossil or living forms. This is thought long overdue. The first bone by bone description of the living cheloniids has revealed a large number of taxonomically useful characters and a close relationship between the genera. However, a great deal of interspecific variation was noted. ‘Chelonia mydas’ is considered to format least three subspecies on cranial evidence. The newly described ‘Natator (Chelonia) depressa’ is thought distinct from other living forms. The Dermochelyidae are seen to be a very conservative group and a large number of cranial characters link fossil and living forms. The arterial circulation of Dermochelys is redescribed and the importance of the blood flow to the head for use by the salt secreting glands in electrolyte balance is shown to be important. The Desmatochelyidae is shown to be a family in its own right, and a number of other genera, notably ‘Rhinochelys’ and ‘Notochelone’, are thought members of the group. Many of the basicranial features identified by Gaffney in the 70s for other fossil groups have been shown to be of use in the taxonomic study of the families under review.
20

Demographics, activity, and habitat selection of the Eastern Box Turtle (terrapene c. carolina) in West Virginia

Weiss, Justin Adam. January 2009 (has links)
Thesis (M.S.)--Marshall University, 2009. / Title from document title page. Includes abstract. Document formatted into pages: contains viii, 88 p. Includes bibliographical references p. 80-88.

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