Fork-tailed Sunbird (Male) - Aethopyga christinae
The male has a metallic blue-green head, dark crimson throat and upper breast as well as decurved bill, with a distinctive trill like call.
This one shot in Kadoorie Farm in mid September.
Resident. Commonly found in woodland and major urban parks.
Breeding season from April to June. Nest is a ball of grass placed in a tree.