An image by Melinda Chan shows a male Brown-throated Sunbird (Anthreptes malacensis) robbing nectar from a hibiscus flower by probing his bill through the base of the flower (left).
Now why did the bird do that?
The natural pollinator of hibiscus has been reported to be the hummingbird. The sunbird is not adapted for hibiscus pollination, so to harvest the nectar in the flower, it has resorted to the unconventional method of probing the base of the flower. This is referred to as robbing, as by doing so the bird is not doing the flower a favour, i.e. assisting in its pollination.
Hibiscus or China rose (Hibiscus rosa-sinensis) is native to continental Asia, probably China. The species has been in cultivation in various forms for centuries and the species itself has never been found in the wild. In Singapore, the plant never produces any fruit or seeds.