ABSTRACT. A study was conducted to observe the population dynamics of residential green turtles, Chelonia mydasin Sipadan Island located off the east coast of Sabah, Malaysia. Three field trips (3 days in each trip) were conducted from August till December 2010. Green turtles were caught from 10 selected dive sites, and were brought into upon the boat for morphometric measurements and tagging using inconel tags from Sabah Parks. At the end of this study, 147 individuals with a mean straight carapace length (SCL) of 652.9 (± 124.2) mm were caught. From the results, 77 individuals were juveniles, 28 were sub-adults, and 42 were adults with mean straight carapace lengths of 557.7 (± 70.5) mm, 690.2 (± 40.7) mm, and 802.8 (± 60.6) mm, respectively. During this study, 20 adult female and 22 adult male were caught with mean straight carapace lengths of 811.1 (±59.2) mm and 795.1 (±62.6), respectively. In our study area, juvenile green turtles were the most abundant as compared to sub-adults and adults. This finding is fundamental in estimating the population of resident green turtles in Sipadan Island and also contributes to better management and conservation of this marine protected area.
KEYWORDS. Green turtles, Chelonia mydas, population dynamics, Sipadan Island, Malaysia