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Subject: 白腰雨燕 Pacific Swift [Print This Page]

Author: Sze Time: 5/04/2009 22:35 Subject: 白腰雨燕 Pacific Swift

Peak of Ma On Shan 馬鞍山頂 05/04/20009

今日係山上見到成3-4隻啊! 可惜多雲唔夠光!

Author: lrichard Time: 6/04/2009 12:34

Good pix!

I think the broad white rump patch indicates that this is the nominate subspecies. I'd be interested to hear what Paul Leader thinks.

Richard

Author: Sze Time: 6/04/2009 22:22

Quote:

Original posted by lrichard at 6/04/2009 12:34
Good pix!

I think the broad white rump patch indicates that this is the nominate subspecies. I'd be interested to hear what Paul Leader thinks.

Richard

Hi Richard! Interesting information! Thanks for your sharing!
Some more photos here. Hope can help to identify! Thanks a lot!

[ Last edited by Sze at 6/04/2009 22:24 ]

Author: lpaul Time: 7/04/2009 12:08

I don't think these are nominate pacificus. They look too small, with relatively short wings and tail for that taxon. Also the tail fork is not particularly deep. The rump is not especially broad and appears to show streaking. Given the location it seems likely that these are locally breeding birds (i.e kanoi). However, there is cline of increasing size in east Asia from kanoi in the south through kurodae (south central Japan) to pacificus in the north. As such identification of individuals in the field to subspecies is very difficult and based on current knowledge only very small birds (kanoi) or very large birds (pacificus) can be safely identified in the field.

It is worth noting that a further taxon (cooki) occurs in south-west China (as close as Yao Shan) and could also occur in HK. This is large, very black subspecies with extensive white tips below.

Author: Sze Time: 8/04/2009 00:56

Quote:

Original posted by lpaul at 7/04/2009 12:08
I don't think these are nominate pacificus. They look too small, with relatively short wings and tail for that taxon. Also the tail fork is not particularly deep. The rump is not especially broad a ...

Paul!Thank you very much for your useful information!
Thanks for your sharing!

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