Cannas are popular border plants with large, showy flowers of red, yellow or yellow spotted with red. These plants are native to tropical America and have been cultivated in Singapore for decades. All these garden cannas are hybrids (below).
The pollinators of canna in its native tropical America are bees, hummingbirds and bats. The local bird species are not adapted to these exotic flowers, so they have found shortcuts, or at least a few of them have, to tap on the nectar without helping to pollinate the flower in the process. This has happened in many exotic garden plants and wayside trees, one example posted recently is the African Tulip.
In canna, Melinda Chan has recently sent an image showing a sunbird poking its bill into the base of the flower to get at the nectar (left). By doing so, the plant has obviously been cheated.
Wells (2007) reports the Crimson Sunbird (Aethopyga siparaja) and Olive-backed Sunbird (Cinnyris jugularis) robbing the flowers of the lily Canna indica of nectar by puncturing through the corolla base.
We encourage the documentation of such nectar harvesting in other exotic flowering plants. If anyone has any such observations or images, please share them.
Melinda Chan & YC Wee
(Top image by YC Wee, bottom by Melinda)
Wells, D.R. (2007). The birds of the Thai-Malay Peninsular. Vol. II, Passerines. Christopher Helm, London.