During my regular evening walks at Admiralty Park in Woodlands, I often spot long-tailed macaques in large numbers with adults and babies.

They are known to be an intelligent species and now I know why.

On Wednesday, I saw one macaque near a bin designed to deter stray animals from stealing food. Instead of an opening, the bin has a flap that has to be pushed, and that's what this macaque did.

It then managed to rummage in the dustbin by supporting itself by its hind legs and not going completely inside the bin and trapping itself.

I have also seen macaques taking out water bottles from unattended bags, opening the caps and drinking from the bottles without spilling the contents.

A. Kannan