Functional Measures of Sea Turtle Hearing
Final rept. 1 Mar 2002-30 Sep 2005
WOODS HOLE OCEANOGRAPHIC INST MA BIOLOGY DEPT
Pagination or Media Count:
Sea turtle hearing was investigated morphometrically by analyzing variations in auditory anatomy a and physiologically by brainstem evoked potential techniques. Auditory brainstem responses ABRs were collected from multiple species and life stages of live sea turtles using an stimulus coupled directly to the turtles tympanum underwater. A three electrode array was used to record the evoked responses to stimuli. Anatomical data were obtained by computerized tomography CT and MRI and histology ABRs obtained from 12 hatchling through sub-adult turtles Lepidochelys kempi, Chelonia mydas, Caretta caretta show juvenile green turtles have a slightly broader hearing range 100-800 Hz best sensitivity 600-700 Hz than sub-adults range 100-500 Hz. Kemps Ridleys had a more restricted range 100-500 Hz with most sensitive hearing at 100-200 Hz. Although this project suggests there are measurable age and species variations in response to underwater sound, the overall results are consistent with prior results for aerial and vibrational stimuli.
- Medicine and Medical Research