SINGAPORE - A new bevy of baby otters was born in the heart of the city this month, drawing much attention from residents and passers-by who came across them at the Singapore River.

When The Straits Times went down on Monday (April 10) afternoon, the family had just ventured out for an afternoon swim in the River.

There were five otter pups, each about six weeks old, and they were taking one of their first swimming lessons.

The scene soon drew a crowd, even as an officer from the National Parks Board (NParks) went around to put up signs on otter watching "ettiquette".

Many took out their cameras and mobile phones to snap photos and videos as the adult otters coaxed the pups into the water. It was quite a jump for the young pups from the bank of the Singapore River, which is a vertical wall.

One by one the seven adults and three pups dived into the water, but two babies remained on the bank.

The otters in the water squeaked and barked at the two pups, which ran along the bank for a few minutes, before jumping into the water - one after the other.

When the brief swimming lesson ended, the family ran up some steps to rest on a small patch of grass by the river side.

Before venturing on land, one of the adults peered cautiously over the edge of the river bank.

By then, about 20 people, including a group of children on their way home from school, had gathered.

Members of the otter watching group reminded them to give the otters space. The skittish mammals can get startled when humans get too close.

"I told them to keep a comfortable distance so that the otters could do what they want to do, instead of having to be on the guard all the time," said Mr Bernard Seah, a wildlife photographer and frequent otter watcher. "If you give them enough space, you can also observe them for a longer time."

When the otter saw that the coast was clear, the rest of the family followed.

While this family of otters have been sighted at the Singapore River for some time, this is the first time there are baby otters at this location. They moved here from Marina Bay in late 2015.

On Sunday, about 80 people gathered to watch them, in a scene similar to the crowds at Bishan-Ang Mo Kio Park in 2015.

There was a stir when the otters there had a bevy of three pups in 2015, and photos and videos of the Bishan otter family went viral.

The Bishan otters moved to the Marina Bay area in late 2015 after winning a "territorial dispute" and "kicking out" the otters originally living there.

Soon after, the losing party made the Singapore River their new home.

Otter watchers who have been observing the families over the years said that they may face difficulties raising babies at this very public location, which has limited access to resting points on land.

"They lost their prime territory at Marina Reservoir, so now the only place to raise their kids is along the Singapore River," said Mr Mr Jeffery Teo, a member of the Otter Working Group. "If they lose this home due to too much human disturbance, they may have nowhere else to go to."

What to do if you encounter otters: