A sea turtle was seen in the sea next to the Marina Barrage on 10 Dec. Thanks to Calvin Ng for sharing this video. He explained that the sea turtle "was sighted on the short viewing platform parallel to the barrage which is just next to the carpark."
Meanwhile, lots of dugong feeding trails were seen at Chek Jawa during a survey on 14 Dec.
Dugong feeding trails are formed when dugongs chomp up seagrasses including their roots, leaving a shallow meandering furrow of about equal width and depth. To eat seagrasses, the dugong pulls out a mouthful of seagrasses with its thick lips, shakes it to get rid of the sand and then swallows.
More about Singapore's sea turtles and dugongs on the wild fact sheets.
For more sightings of mega fauna in Singapore waters.