Date of Award
2018
Document Type
Thesis
Publication Status
Version of Record
Submission Date
October 2026
Thesis/Dissertation Advisor [Chair]
Salmon, Michael
Abstract
Hatchling marine turtles use visual cues to orient from their nest to the sea at night. However, the wavelengths of light that carry this information have not been properly documented, nor do we understand why they are favored. I measured wavelength irradiance at 20 nm intervals between 340 – 600 nm at a dark nesting beach and then, in the laboratory, determined the thresholds of the hatchlings for each λ that evoked a positive phototaxis. In this study, I show that green turtle hatchlings are (i) most sensitive to the shorter (360 – 480 nm) light wavelengths. Those light energies (ii) dominated the available natural lighting at the nesting beach. They also (iii) presented a steep gradient in irradiance between a landward and seaward view, an important cue for orientation. I attribute the phototactic responses to “stimulus filtering”, the outcome of natural selection that optimizes behavioral responses (seafinding) according to their function, as well as when and where they occur.
Extent
43 p.
Recommended Citation
Celano, Lisa, "Seafinding by the green turtle, Chelonia mydas: the orientation response is tuned to the lighting environment at the nesting beach" (2018). Electronic Theses and Dissertations 2010 - 2019. 2010.
https://digitalcommons.fau.edu/etd_general_6/2010
Identifier
FA00013034
Comments
Includes bibliography.|Thesis (M.S.)--Florida Atlantic University, 2018.|FAU Electronic Theses and Dissertations Collection|Includes bibliography.