A new technique for monitoring grazing behavior of Hawksbill turtles (Eretmochelys imbricata) using acceleration data loggers

Abstract

Grazing behavior of sea turtles is important to understand their behavioral ecology. However, there is a shortage of effective techniques available for monitoring the grazing behavior accurately over a long period. In this study, the grazing behavior of hawksbill turtles (Eretmochelys imbricata) was monitored with acceleration data loggers which recorded depth, temperature, and accelerations in two axes. A Juvenile hawksbill turtle was attached with two acceleration data loggers on both head and carapace. During the experiment, we recorded the behavior of turtles on the underwater digital video camera. Their behaviors were distinguished into four patterns through the acceleration profiles and the underwater observation as follows; resting, swimming, grazing and breathing. The new technique can clarify when and where turtles graze quantitatively as well as time allocation of their behavior patterns.