Look before you step into the water near Kranji and Lim Chu Kang if you do not want a nasty, toothy shock.
More saltwater crocodiles, the world's largest living reptiles and one of the most fearsome predators, have moved into Singapore waters.
Experts told The Sunday Times that up to 10 crocodiles now live in and around Singapore's north-western coast, up from only two confirmed by the National Parks Board (NParks) in 2008.
Most are within the Sungei Buloh Wetland Reserve, but some are known to roam Kranji Reservoir too.
Last Sunday, a small crowd of excited visitors to Sungei Buloh saw two crocodiles in the river at about 8am, apparently a good time to spot the creatures basking in the sun.
"They were feeding on a shoal of fish caught in the low tide," said gynaecologist Yap Lip Kee, who was on his regular walk in the area.
The 1.5m crocodiles were languidly floating facing upstream, he said, swallowing fish that strayed too close to their jaws.
The avid wildlife photographer, who enjoys his solo walks there every other month, immediately started snapping away with his camera. He has seen crocodiles in the area on four other occasions.
He said: "It's quite a privilege to observe animal behaviour like this, especially when most people have to pay a fortune to go on safari to do so. And to be able to do it from a safe spot on a bridge too!"
Other crocodiles spotted in the past near Pasir Ris and Woodlands had likely visited from Malaysia, experts said.
The reptiles are known to swim freely in the Straits of Johor, and feed and rest in mangroves and freshwater bodies along Singapore's north coast.
While seawater crocodiles can grow up to the length of two small cars, the ones here tend to remain under 3m because their habitats are smaller, said wildlife consultant Subaraj Rajathurai.
He said their increased presence shows that Singapore's protected habitats are thriving. Some crocodiles may have been forced out of Johor waters by development there, he said.
"Thirty to 40 years ago, villagers here used to live with crocodiles around them. Then they were hunted to near extinction," he said.
"What we're seeing in Sungei Buloh is actually a validation that the ecosystem there is maturing."
People have little to fear so long as they stick to designated footpaths and do not venture close to the water in areas where crocodiles have been seen.
Dr Brady Barr, a reptile and amphibian expert and National Geographic Channel host, said: "The chances of being hit by a car in Singapore are greater than a crocodile taking a bite out of you... but there is a responsibility that comes with living in an area inhabited by them."
NParks' director of conservation Wong Tuan Wah advised visitors to heed warning signs placed in the reserve, and to stay calm and back away slowly should they come across a crocodile on a footpath.
But Dr Barr said people should be thankful to catch a glimpse of the giant reptiles.
"If you encounter a crocodile, feel fortunate that you have seen such an amazing animal. They have been around for over 200 million years, long before we started taking over their habitat," he said.
This story was first published in The Straits Times on June 2, 2013
To subscribe to The Straits Times, please go to http://www.sphsubscription.com.sg/eshop/