Tagging, nesting and photo-indentifications of green turtles (Cheloniidae: chelonia mydas) at Chagar Hutang, Redang Island

Abstract

Research on sea turtles is primarily done by monitoring and tagging activities on nesting beaches. While tagging allows information on nesting biology to be obtained, tag loss causes bias in sea turtles studies. This study was conducted to obtain a more in-depth analysis on the tagging and nesting data collected by Universiti Malaysia Terengganu (UMT) from 1993-2014 in addition to exploring the feasibility of implementing photo-identification (photo-ID) in tagging sea turtles. Field work was conducted in March 2013 until May 2014. Tag loss and nesting data was analysed by extracting data from the File Maker Pro database.

A total of 1595 green turtles were tagged throughout the 22 years of conservation program at Chagar Hutang. The average intra-seasonal tag loss probability valued at 0.015 and 0.027, and inter-seasonal at 0.256 and 0.253 for Inconel and titanium tags, respectively. No distinct increasing or decreasing trend in tag loss with tag age (year) was observed. The peak nesting season was during May-August where 78.9% of the nestings occurred.