Amur Falcon is a bird that has only been known in Hong Kong for the past umpteen years.
It's possible that some were overlooked as Eurasian Hobby (Falco subbuteo) in the past. They are autumn migrants, and they turn up in Hong Kong between leaving their breeding areas in northern China and Russia and their wintering grounds in southern Africa.
|Amur Falcon - Falco amurensis
Don't take my word for it - Wikipedia has a lot on this species: https://en.wikipedia.org/wiki/Amur_falcon
A couple of years ago, Amur Falcon was in the news recently for the wrong reasons, when it was revealed in 2013 that they were being trapped by the hundreds in the Indian State of Nagaland and sold for food. However, a big effort by Indian and overseas conservation groups seems to have turned this around by creating a festival for tourism and birders, as outlined here : http://www.easternmirrornagaland.com/the-story-of-amur-falcon-its-conservation-and-safe-passage/
Birdlife South Africa has been satellite-tracking Amur Falcons, too. The progress of individuals can be monitored and posted on the internet within hours.
|@copyright Birdlife South Africa
On leaving India, bound southwest, they'll fly across the Indian Ocean, feeding on migrating dragonflies over the sea.
Very confiding for a small raptor, they can be a photographers' favourite....they are certainly one of mine, anyway.
They can scratch their heads and wonder how they are going to get to where they need to be...but sooner or later they just need to "get on with it"...
They have a long way to go.