THE INFLUENCE OF SAND PARTICLE SIZE ON NESTING SITE SELECTION OF PAINTED TERRAPIN (CALLAGUR BORNEONESIS) IN KUALA SETIU BARU, PENARIK, TERENGGANU

Abstract

Painted terrapin or Callagur borneonesis is among Malaysia’s most endangered freshwater turtle species that was enlisted as Critically Endangered by the International Union for Conservation of Nature (IUCN) in 1990. In Malaysia, the biggest population of the species can be found in Sungai Setiu, Terengganu. The nesting behavior pattern of Painted terrapin was studied with focus on its relation to the sand particle size in the coastal beach where the terrapins lay their eggs. The findings showed that there was a correlation between distribution of sand particle size and nesting density of the Painted terrapin in this area. Horizontal analysis showed that as sand particle size gets larger further from the river mouth , the number of nest decreases (r₂ =0.85). Vertical analysis showed that as sand particle size gets larger further upward from the shoreline, the number of nest increases (r₂=0.99). Painted terrapin showed preference to nest and lay their eggs at sand with smaller particle size. The straight-line equation of the analysis is y=4.67x – 1.56 for horizontal analysis and y=21.84x – 16.71 for vertical analysis. Average nest depth is 17.1cm. Average nest incubation temperature is 29.2⁰c. Average nest distance from the shoreline is 28.9m. Average nest distance from nearest vegetation is 15.4m. Average size of terrapin eggs is 8.72cm in length and 5.54cm in maximum width. The findings suggested the required buffer zone that would be useful for PERHILITAN Department in order to set up a new policy on terrapin conservation and rehabilitation.