The Crimson Sunbird (Aethopyga siparaja) is a species of bird in the sunbird family which feed largely on nectar, although they will also take insects, especially when feeding young. Flight is fast and direct on their short wings. Most species can take nectar by hovering like a hummingbird, but usually perch to feed most of the time.
This is a common breeding resident in Singapore.
It inhabits gardens and forests.
The male is a distinctive reddish sunbird. The female is likely to be confused with other female sunbirds, but it has a darker appearance, long curved bill, no sign of prominent eye ring and a longish tail.