Date of Award
2012
Document Type
Thesis
Publication Status
Version of Record
Submission Date
October 2026
Abstract
Little is known about the visual capabilities of marine turtles. The ability to discriminate between colors has not been adequately demonstrated on the basis of behavioral criteria. I used a three-part methodology to determine if color discrimination occurred. FIrst, I exposed naèive, light-adapted hatchlings to either a blue, green or yellow light. I manipulated light intensity to obtain a behavioral phototaxis threshold to each color, which provided a range of intensities we knew turtles could detect. Second, I used food to train older turtles to swim toward one light color, and then to discriminate between the rewarded light and another light color ; lights were presented at intensities equally above the phototaxis threshold. Lastly, I varied light intensity so that brightness could not be used as a discrimination cue. Six turtles completed this task and showed a clear ability to select a rewarded over a non-rewarded color, regardless of stimulus intensity. Turtles most rapidly learned to associate shorter wavelengths (blue) with food. My results clearly show loggerheads have color vision. Further investigation is required to determine how marine turtles exploit this capability.
Extent
x, 43 p. : ill. (some col.)
Recommended Citation
Young, Morgan, "Visual wavelength discrimination by the loggerhead turtle, Caretta caretta" (2012). Electronic Theses and Dissertations 2010 - 2019. 671.
https://digitalcommons.fau.edu/etd_general_6/671
Identifier
FADT3352879
Comments
by Morgan Young.|Thesis (M.S.)--Florida Atlantic University, 2012.|Includes bibliography.|Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.|by Morgan Young.