This video says about itself:
Great Frigatebird juveniles (Fregata minor palmerstoni) playing with a stick over Eastern Is., Midway Atoll.
From India eNews:
Global warming brings tropical birds to Hong Kong
From correspondents in Hong Kong, China
The sighting of two rarely seen tropical birds in Hong Kong could be due to climate change, bird experts here have said.
It was the first time the white-tailed tropic has ever been spotted in Hong Kong and only the fourth sighting of the frigate.