Experimental Analysis of Wavelength Preferences Shown by Hatchling Leatherback Sea Turtles (Dermochelys coriacea)

Abstract

In marine turtles it is well established that the shorter light wavelengths in the visible and near-ultraviolet spectrum provide more potent, and preferred, cues for nocturnal seafinding orientation than the longer light wavelengths. In this study, we simultaneously presented leatherback hatchlings (Dermochelys coriacea) with a short near-ultraviolet (380 nm) and a longer visible (500 nm) light stimulus to determine whether that preference was based upon differences in light intensity, light wavelength, or a combination of both variables. We found that under light conditions mimicking those at the nesting beach on the darkest evenings, the behavioral preference for the shorter light wavelengths was based upon intensity cues, although we speculate that under brighter illumination, wavelength cues might also be utilized.