HFCheung

Yesterday I noticed that there were large flock of Tree Sparrow coming to roost in town (Baoshan, Yunnan).  Today I did a count.  Here is the result.

No. of birds: 5100
Time of influx: 7:40-8:20 pm (baoshan is about 1 hr to the west of HK).

Here is the photo of the site.  There were about 10 trees close together on a very busy street.  I guess the busy traffic help to conceal the noise of the bird before they sleep.

IMG_0472p.jpg (133.1 KB)

20/07/2014 20:55

HF Cheung

[ Last edited by HFCheung at 20/07/2014 20:56 ]

John Holmes

That's a LOT of Tree Sparrows in a few small trees !  I saw something similar (but on a smaller scale) in a town near XTBG, south Yunnan, a couple of years ago.

HFCheung

The main reason for birds to cling together is for safety, is that right?  Like Black-faced Spoonbill, their breeding sites are highly concentrated at a few islands.
Tree sparrow has been killed heavily during the cultural revolution.  There are many towns such as Wuyuan, Jiangxi start to see good numbers of Tree Sparrow coming back.
Egretries in mainland China tend to be huge, while those in HK are much more spread out.  So I guess Egrets in HK feel more secure.  
I am not an academic in this area, may be this is already a well known fact in academic circle.

wcaptain

The nesting population of egrets and herons depends on area of feeding habitats

In Hainan, some colonies can be over 1000 nests, while in HK the largest one is around 200 nests. This reflects the smaller area of feeding habitats in HK than Hainan.

[ Last edited by wcaptain at 22/07/2014 15:37 ]