ajohn

Sadly, given the situation in Guangdong I think it is most likely that the Collared Crow is a Hong Kong bird. I'm surprised this is the first Po Toi record - I have seen them several times at Aberdeen (despite the fact that I am not there often!) and I had a flock of six on Lamma a few weeks ago.

ajohn

I don't know all the reasons for the decline of Collared Crow in China but it's probably a combination of habitat loss, persecution and poisoning by rodenticide. BirdLife lists it as Near Threatened (http://www.birdlife.org/datazone/speciesfactsheet.php?id=5792), but it is possible that it warrants a higher threat category.

Whatever the reason, by all accounts it's now rare to see in China. People regularly visiting Guangdong in recent years (e.g. Jonathan Martinez, Brian Ivon Jones) have not been recording it. Hong Kong seems to be a global stronghold for the species, and fortunately it is doing very well here.