1.  This study was performed to investigate a mechanism of heat exchange in sea turtles and how temperature and different acclimation time affects their metabolic rates.  In another part of this thesis I aimed to test the possibility of a correlation between dive duration and both metabolic rate and state of buoyancy known to be regulated via the gas volume in the lungs of Chelonian sea turtles. 2.  All experiments were conducted on captive loggerhead (<i>Caretta caretta) </i>and green turtles (<i>Chelonia mydas)</i> housed in a individual tanks with circulating seawater from the adjacent Gulf of Naples (Western Mediterranean). The total range of body masses of turtles used encompassed 2 to 60 kg. 3.  It was demonstrated, using Doppler ultrasound, that sea turtles change blood flow in their appendages in response to external cooling and heating. Although this was efficient to accelerate whole body warming and delay the cooling of the body, turtles eventually equilibrated their body temperatures with that of the surrounding water. 4.  The Q₁₀ effect on metabolic rate of sea turtles subject to acute exposure to varying temperatures was 1.3. However, during long term exposure to seasonally decreasing water temperatures turtles showed a more pronounced reducted of metabolic rate (O₁₀ = 5.4). Contemporaneously food intake and general activity were greatly reduced as well and dive durations increased.  Body temperatures showed the same seasonal trend as the decreasing water temperatures. 5. Oxygen consumption rates of individual turtles, measured over 24-h-periods, peaked at different times of the day and no specific dynamic action after feeding could be detected.

Thesis (Ph. D.)--University of Florida, 1981. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 155-162).

Posthatchling green (Chelonia mydas) and loggerhead (Caretta caretta) turtles overlap ecologically but differ morphologically. This study compared hydrodynamic stability between the two species during swimming to test for functional differences in body shape. Flipper movement paths, four stability measures (yaw, pitch, heave, and sideslip), and the relative positions of the centers of buoyancy and gravity were compared between species. Both centers of buoyancy and gravity lie in the anterior body; their positions relative to one another differed with species, but showed no functional consequences. Neither species demonstrated substantial yaw, sideslip, or pitch. Both experienced upward heave with the flippers' downstroke and downward heave with the upstroke; however phase relationships differed between these limb and body motions. No differences were found between the two species. Despite obvious morphological differences, loggerheads and green turtles were similarly stable during swimming, suggesting that the species use different mechanisms to achieve stability. / by Erin Dougherty. / Thesis (M.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 56-60). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Hong Kong, 2008.

Thesis (M.S.)--University of North Carolina Wilmington, 2009. / Title from PDF title page (January 12, 2010) Includes bibliographical references (p. 64-69)

No description available.

In sea turtles, body condition can be evaluated through subjective body condition scoring (BCS), calculating body condition index (BCI), and clinical blood parameters. The goal of this study was to analyze ultrasonography of subcutaneous fat depth as a method to estimate body condition in 10 green and 8 loggerhead sea turtle carcasses using two types of portable ultrasound technologies, the Ibex Evo® and the Renco Lean-Meater®. Despite the general lack of significant correlations between ultrasound-assisted, gross, and histological measurements, the dorsal shoulder and lateral neck were determined to provide the most consistent images of subcutaneous fat. Florida live-captured green turtles were sampled and ultrasound-assisted fat depth measurements were taken at the dorsal shoulder region; however, there were no significant correlations found between fat depth and BCI or blood analytes (PCV, total protein). BCI reference quartiles were created using associations between BCI and BCS to help provide biological context to BCI data and allow for rapid categorization of sea turtle body condition. / Includes bibliography. / Thesis (MS)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection

The seasonal and diel movements of fourteen immature green turtles (Chelonia mydas) in Mosquito, Lagoon, Florida were monitored using sonic telemetry. The feeding ecology of this turtle population was also studied using dissection and stomach flushing techniques. An attempt was made to relate the movement patterns of the turtles to their feeding habits. The immature green turtles were found to make seemingly random, long distance movements (X̄km moved/day=7.79) and to remain in deeper waters (X̄depth=1.63m), apparently not feeding, when water temperatures fell below 19°C. When average water temperatures ranged between 19-25°C, the turtles were found primarily in shallow waters (X̄depth=1.1m) and demonstrated a decrease in agility (X̄km moved/day=3.14). At water temperatures above 25°C, the animals became even less agile (2.58 km moved per day) and adopted a home range area that included a "center of activity" and a "home site." A "shuttling" behavior was observed when water temperatures averaged 31°C and higher. In the early mornings, turtles were found feeding on the grass flats. When shallow water temperatures rose above 30°C at midday, the turtles would relocate to deeper water. In late afternoon, they would return to the grass flats for a short period of time. Sea grasses made up 88% of the lagoonal turtle diet, with manatee grass (Syringodium filirorme) alone constituting 77%. No significant difference was found in per cent composition of stomach contents obtained in January via dissection and August via pumping.

Clutches of eggs wore collected from nesting loggerhead sea turtles (Caretta caretta caretta) on Merritt Island, Florida, during June - August 1977. Of these, 46 clutches were selected for experimentation to determine the extent to which certain factors affect hatching success. Twelve clutches were divided into subsamples which were incubated in sand maintained at 0, 25, 50, 75, and 100% moisture. Another twelve clutches were divided into subsamples and incubated in sand kept moist with the following percentages of seawater: 0 (distilled water), 25, 50, 75, and 100%; subsamples from four other clutches were subjected to the effects of one tidal inundation. Eggs from four of the clutches used in the moisture and salinity experiments were monitored for changes in size. Fifteen clutches were divided into subsamples which were kept in incubators maintained at 20, 24, 27, 30, 32, 35, and 38°C; subsamples from seven of these clutches were moved from unfavorable to optimal temperatures to study their ability to recover from stress. Three clutches were selected for an experiment to determine the effects of handling on hatching success; the following year, another five clutches were used for similar studies. Some of the hatchling turtles produced in this project were abnormal, and these were discussed in depth. From the experiments, it was determined that 25% moisture, 0-25% seawater, and 27°C produced the maximum percent hatch. The effects of handling on hatching success depended variably on the time and manner of handling. The optimum values indicated in the experiments closely approximated values for moisture, salinity, and temperature obtained from natural turtle nests on the beach.