SINGAPORE - Dark and murky waters surround Pulau Hantu, an island off Singapore's southern coast.
But go deeper - 6m to 16m under, as The Straits Times did on a scuba-diving trip last Saturday - and one discovers a "marine parade".
Bathed in green and yellow, this underwater town is dotted with hard rocks and corals that are branched out like trees. Shiny fish dart in and out so fast that they appear as slivers of silver - they are the speedsters of the aquatic world.
Like a shy schoolgirl at her first dance, a copper-banded butterfly fish hangs around just long enough to be seen but zooms away when approached.
Farther along the reef, soft corals sway in the underwater current, as though jiving to the music of revving motorboat engines and ship horns. Here, as on land, there is no avoiding heavy traffic.
Despite a name that means Ghost Island, Pulau Hantu is surrounded by life, rich sea life. Likewise, Singapore, the last place people think of when they think nature and wildlife, has plenty of bounty under the sea.
The waters around Singapore are home to more than 250 species of hard corals alone - about 40 per cent of the types of corals found in South-east Asia.
Corals are found not only around Pulau Hantu but also near other islands such as Pulau Sudong, a restricted area used by the military for live firing. Lucky divers get glimpses of sea turtles, dolphins or even reef sharks.
But it is not easy to see what lies beneath.
The waters around Pulau Hantu, for instance, are heavily sedimented, with visibility going only as far as an outstretched arm.
Yet, up until the mid-1960s, Singapore had waters as clear as those at Tioman, said marine conservationist and lawyer Francis Lee, 68.
National University of Singapore (NUS) marine biologist Chou Loke Ming said back then, corals and other reef life at 10m underwater could be seen from a boat.
But as Mr Lee said: "But by the late 1960s, the clarity of the waters went downhill."
Most of the damage was caused by intensive land reclamation and development, he added.