Keywords
Serum testosterone levels, Loggerhead turtle (Caretta caretta), Green turtle (Chelonia mydas), Indian River, Central Florida, Sexual maturation threshold (75 cm carapace length)
Abstract
A yearlong hormonal study of immature populations of loggerhead turtles (Caretta caretta) and green turtles (Chelonia mydas) inhabiting the Indian River in Central Florida, USA, provided information about the relationship between serum testosterone levels and life history habits. By use of a specific radioimmunoassay, testosterone levels of both species were found to remain constant throughout the year with only a slight increase in the warmer months. Adrenal production of steroids in response to stress does not contribute significantly to overall testosterone levels may be reduced for turtles held in captivity. Testosterone levels indicate that the sex ratios of both species were not significantly different from an expected 1 female : 1 male ratio. Loggerhead and green turtles may begin maturing sexually at a straight line carapace length of 75 cm. Mean testosterone levels of the loggerhead population were greater than those for green turtles in all four seasons, undoubtedly because the loggerheads are older and closer to sexual maturity.
Notes
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Graduation Date
1987
Semester
Summer
Advisor
Ehrhart, Llewellyn M.
Degree
Master of Science (M.S.)
College
College of Arts and Sciences
Department
Biology
Format
Pages
71 pages
Language
English
Rights
Public Domain
Length of Campus-only Access
None
Access Status
Masters Thesis (Open Access)
Identifier
DP0020549
Subjects
Sea turtles--Research; Turtles--Physiology; Testosterone; Reproduction--Seasonal variations; Sex ratio--Endocrine aspects
STARS Citation
Luepschen, Lawrence K., "Seasonal Variation in Serum Testosterone of Immature Sea Turtles in Central Florida" (1987). Retrospective Theses and Dissertations. 5045.
https://stars.library.ucf.edu/rtd/5045
Contributor (Linked data)
Accessibility Status
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