The main laying beach is on the east and south-western parts of the island. The largest island and nearest to the Philippines border. Active mud volcanoes are present. The northern and western beaches are favoured by the green turtles. Gulisan Only about 1.6 hectares in area.
Turtles lay their eggs on the northern, eastern and south-western beaches.
They normally come ashore after 7.30 p.m. but have also been observed nesting between 5 to 6 in the morning. The time it takes for the turtle to emerge from the sea until when it conceals its eggs with sand is usually about an hour. It selects and clears its nesting site and using its rear flippers, digs a pit 12 to 18 inches deep. It then lays a clutch of 40 to 190 eggs into the pit and carefully conceals it by covering it with sand before returning to the sea. During the eggs laying process the eyes of the turtle are covered by a colourless mucus which prevents dehydration and also to deep out from any sand.