It was evening and the drizzle had just stopped. A male Olive-backed Sunbird (Cinnyris jugularis) flew in and perched on the large pink bract of the inflorescence of the Wild Banana (Musa ornata) (above). The sunbird was alone and there was thus no competition to feed on the flower nectar.
Sunbirds probes into these flower at the base to get direct access to the nectar (above). By doing this its bill does not make contact with the pollen if it is a male flower and pass pollen to the stigma if it is a female flower. Thus it does not help in the pollination of the female flowers. Sunbirds are thus termed “stealing” nectar. Why does this happen? Its bill is a little short to reach the nectar if it is to probe the flower from the top, unlike spiderhunters, with longer bills, see LINK.
The video clip above shows the entire process of the sunbird stealing nectar. Whenever the sunbird has its bill pierced into the base of the flower, the throat can be seen vibrating, indicating that suction is being applied to pump nectar into its “tubular” tongue. Towards the end of the clip (at 2:20 and 2:54) the tongue can clearly be seen projecting beyond the tip of the bill (see below and LINK).
18th November 2017