SINGAPORE - In his 10 years of fishing, Mr Quek Wei Teck has never come across anything like it.

The 39-year-old was with six other friends on a yacht off Pulau Semakau last Saturday afternoon (June 16) when they saw something jump from the water.

"All of us stopped fishing and rushed to the front (of the yacht)," said Mr Quek, who owns a fishing academy.

As they got closer, they were treated to the sight of at least six dolphins - one of which appeared "a bit pinkish in colour", he told The Straits Times on Tuesday.

As the yacht inched slowly towards the pod so the fishing enthusiasts could get a closer look, the dolphins continued frolicking in the water.

"The nearest we got was about 10 to 20m," Mr Quek said. "We've been there many times but it was our first time seeing dolphins."

The group then whipped out their camera phones to try to capture the sighting.

Chairman of the Nature Society (Singapore)'s Marine Conservation Group Stephen Beng told ST that the dolphins are Indo-Pacific humpbacked dolphins, or pink dolphins - named after the colour they grow into with age.

The dolphins of this species are common in Singapore waters, and have been observed around the southern islands, Mr Beng added.

"It's good that these dolphins are commonly spotted in our reefs," he added. "It is important for us to be aware of their existence in our waters, and that they are part of our reef ecosystem."

He added that people should not discard fishing lines and nets in the sea, as they pose a threat to the marine life living in the waters, including dolphins, otters and sea turtles.

In April this year, a dolphin was spotted at Bedok Jetty, after it was reportedly caught in a fishing line.

After about 15 minutes, the fisherman cut the line and the dolphin drifted away into the waters, according to an eyewitness.