The internesting diving behaviour of the leatherback turtle

• Main Author: Myers, A. E.
• Published: Swansea University 2006
• Subjects: 591.5
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.638287

During spring and summer 2003 data were collected from the leatherback population nesting on a beach in Grenada, West Indies. By attaching data logging devices to leatherbacks I was able to record certain aspects of their behaviour whilst at sea between nesting events. Three different device types were used in these studies: Satellite Relayed Data Loggers (SRDLs), Time depth recorders (TDRs) and mouth opening sensors. The SRDLs as well as providing location fixes, transmit limited dive data to overpassing satellites. After introducing various aspects of leatherback biology and ecology (chapter 1) and describing the methodologies used to collect and process the data (chapter 2) I then go on to validate this data collected by the SRDLs (chapter 3). This was achieved by attaching, to the same animal, an SRDL and a TDR (which record depth and temperature at a predetermined sampling interval). The fourth chapter focuses specifically on the data acquired by the TDRs particularly in relation to diel periodicity and the function of deep dives. Chapter five pertains to the crepuscular diving behaviour of leatherbacks. In this chapter I predict how the turtles will behave according to optimal foraging theory and then investigate these predictions using the data collected by the TDRs. Chapters six and seven involves a thorough investigation into the mouth opening data collected. In chapter six I examine the breathing patterns and mouth opening behaviour of the turtle during dives whilst in chapter seven I focus on some unexpected oscillations being recorded by the mouth opening sensor.