I have spotted this dog faced water snake (Cerberus rynchops) a dozen times in mangrove forest. In Greek mythology, Cerberus is the three-headed watchdog of gate to HELL (welcome you to enter but stop you from leaving, muhaha…). Despite its nasty name, this snake has only one head, and its mild poison is not strong enough to kill a man. Their brown skin blends perfectly into their surrounding, so 99% of the tourists, even the frequent visitors, never spot this snake.
Dog Faced Water Snake is a nocturnal snake, which means it is active at night. To see it during daytime, you really need some luck. Based on my experience, you have better chance of seeing it under one of the conditions below:
1) After a heavy rain last night. In the next morning, you would find this snake rests on a mangrove tree root. It does not like exposed open space very much. Look for roots that have a bit of covering above them, such as leaves or branches, but partially accessible by soft sunlight (see picture below). I have near to 100% chance of seeing them under such condition. I suspect they come out for a sunbathe, due to the cold water brought by heavy rain.
2) After 5pm or before 9am, you would find it moving slowly in the shallow water, looking for food such as mudskippers, lizards, frogs, and small fishes. You can Click Here to watch the video clip (Length: 2 minutes, Size: 4.7 MB). Since they move under the water, it is easier to find them during low tide. In the video, you can see that it tried to check out every burrows along the path, and it stays under the water most of the time. The normal snakes would feel more comfortable keeping their heads above the water while swimming.
3) At night. A local nature journal reported that someone saw dozens of water snakes crawling on the mudflat at night, searching for food. The park closed at 6pm, so I didn’t try this.
So now you learn my “secrets”. In the past, without any knowledge about it, I could not find them even after more than 20 times visit to the forest. You have to walked slowly and scan for S shape on the roots. The fun thing is they like to appear at the same spot. The next visit you would see them again around that area. The eyes of this snake are situated on the top of the head. This enables it to see above water and the rest of the body submerged. I found that they have very poor vision. They are not alerted if you remain still about 5 feet away.
Photos taken in Kota Kinabalu Wetland Centre, Sabah, Malaysia