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Subject: Red-backed Shrike 紅背伯勞 [Print This Page]
Author: twaiyi    Time: 7/10/2008 19:29     Subject: Red-backed Shrike 紅背伯勞

7-10-2008
九龍  KLN

Tiger Shrike?

A bit different from Brown Shrike, please help















[ Last edited by twaiyi at 14/10/2008 23:05 ]
Author: lchunfai    Time: 7/10/2008 20:09

I think this is Tiger Shrike
Author: lmichael    Time: 7/10/2008 20:37     Subject: Red-backed Shrike

Paul Leader and I are almost certain that this is a Red-backed Shrike - first for Hong Kong.

Main reasons are relatively small bill (similar to Brown Shrike), extensive pale fringes to tertials, incomplete eye ring, fairly bright rufous head with limited barring (heavily barred but not rufous on Tiger).

Well done twaiyi - an excellent record and a bird which a lot of people would like to see, please could you post details of where you saw it and/or contact BirdLine.

Mike Leven
Author: mclisa    Time: 7/10/2008 21:51

i want to know how to distinguish it from the red-back to the first winter of brown shrike? they look so similar.
Author: kmatthew    Time: 7/10/2008 23:33

We got one of those in my village just last week (UK)!! Though I didn't get to see it...it does looks like a Red-backed Shrike similar to that at my village (looking at photos other took)!! Great record if confrimed!! Here is a link to a photo of the Red-backed at my village: http://www.freewebs.com/levels-birder/R%20B%20Shrike%20(270908)%20juv3_filtered.jpg
Author: lmichael    Time: 8/10/2008 09:52     Subject: Red-backed Shrike

Regarding the post on separation from Brown Shrike, I didn't mean that Red-backed Shrike looked like Brown Shrike, just that the bill size and shape is similar unlike the heavy (very deep) bill of Tiger Shrike.

Mike Leven

[ Last edited by lmichael at 10/10/2008 10:00 ]
Author: lchunfai    Time: 8/10/2008 12:19

Thx all for teaching me a  new thing.
Author: ajohn    Time: 8/10/2008 17:22

Several people were able to see the bird today, and there seems to be general agreement that this is indeed a Red-backed Shrike. Thank you to all involved and congratulations to twaiyi on such a stunning find - a beautiful, and somewhat unexpected, bird to brighten this autumn!

When I was present everybody was being well-behaved, keeping back from the bird, which was actively hunting among the trees. I urge anyone else who visits the site to stay back and not disturb the bird - it is fairly tame but would still be disturbed if you approach too close. As in all situations when watching birds, it is best to give the bird some space rather than harass it (especially if, as in this case, the bird is a migrant) - if the shrike behaves as it did today, then by sitting quietly observers will probably be rewarded eventually by close views of the bird as it moves around it's favoured area.

[ Last edited by ajohn at 8/10/2008 17:23 ]
Author: HFCheung    Time: 8/10/2008 17:44

Well done!  I am glad that somebody have the chance of checking it themselves.

This incidence remind me of the same old question of keeping the site of important birds secret.  I am not insisting how this should be done one way or the other.  I am saying that we should have a uniform scale for ourselves and others.  If we want to keep this secret, then I think we better not blame others not to reveal their own secret sites.

HF Cheung
Author: lpaul    Time: 9/10/2008 13:14

Having seen the bird (thank you very much twaiyi) and done a little more research I am completely happy that this is Red-backed for the following reasons:

Tail structure: very short distance between shortest and longest tail feathers and very square-cut tail.  On Brown the tail is more rounded with a greater difference between the shortest and longest tail feathers, in addition the send outermost is obviously shorter than the longest which is not the case with Red-backed

Primary projection: about 75% of the exposed tertials, but about 60% on Brown.

Wing formula: The second primary tips falls between the fourth and fifth primaries which is spot on for Red-backed, on Brown the second primary tip typically falls between the fifth and sixth primaries.

Bill structure: rather delicate and not as deep or strongly curved as on Brown Shrike.

Pattern of greater coverts: the broad pale fringe with a blackish sub-terminal line and a pale centre is typical of Red-backed.  On Brown the greater coverts are extremely dark and with a broad rufous fringe.

Pattern of the tertials: pretty much as per the greater coverts for both species, but especially so on the shortest tertial.

Underparts: Whitish ground colour with neat black crescents; on Brown the underparts would be sullied buff and would be darker on the flanks.

Upperparts: slightly browner and more rufescent than Brown.  When I saw the bird it was nothing like as rufescent as it looks on the posted photos and looked very similar to a first winter nominate cristatus at times but not so dark.
Author: gary    Time: 9/10/2008 19:47

Speaking about the bird,
Refering to guide book, Brown should be 2cm larger than Red-backed, a 10 % size difference which should be notable in the field.
Could someone lucky to have seen the bird tell if it's true for this bird?

Gary
Author: Beetle    Time: 9/10/2008 20:02

Quote:
Original posted by gary at 9/10/2008 19:47
Speaking about the bird,
Refering to guide book, Brown should be 2cm larger than Red-backed, a 10 % size difference which should be notable in the field.
Could someone lucky to have seen the bird tell ...
i cannot tell the difference in size between this bird and the brown shrikes i've seen before. Very similar in size.
But my guide books says brown shrike is 19-20cm (birds of South-East Asia) or 20cm (birds of hk and S china, Field guide to the birds of china),
and Red-backed is 19cm (Field guide to the birds of china).
The field guides may not be correct enough, as yours and mine all show slightly different values.
Author: mclisa    Time: 9/10/2008 23:00

Quote:
Original posted by lpaul at 9/10/2008 13:14
Having seen the bird (thank you very much twaiyi) and done a little more research I am completely happy that this is Red-backed for the following reasons:

Tail structure: very short distance between  ...
Thanks for your detailed descriptions, i learnt a lot about "observation"! good birding to all. Hope we can put more focus on our interest and heart to treasure the nature!
Author: twaiyi    Time: 10/10/2008 18:24

Just a report,
the Shirke is not here today.
Author: Web Osprey    Time: 11/10/2008 23:58

there was a brown shrike there Yesterday and only a stonechat left Today.
Author: blackpipi    Time: 29/10/2008 19:44

Hi, Hong Kong birders  I come from Tainan, Taiwan. We have 2 "suspects" in Taiwan. Are they both Red-backed Shrikes?

No.1-1＆2(Photographed by Liu)

[ 本帖最後由 blackpipi 於 19/12/2008 22:55 編輯 ]

Image Attachment: 紅背伯勞1（劉）.jpg (19/12/2008 22:55, 84.27 KB) / Download count 636
http://www.hkbws.org.hk/BBS/attachment.php?aid=2670



Image Attachment: 紅背伯勞2（劉）.jpg (19/12/2008 22:55, 82.84 KB) / Download count 685
http://www.hkbws.org.hk/BBS/attachment.php?aid=2671

Author: blackpipi    Time: 29/10/2008 19:50

No.2

Thank you for helping identifying.

Image Attachment: R01.jpg (29/10/2008 19:50, 86.25 KB) / Download count 685
http://www.hkbws.org.hk/BBS/attachment.php?aid=2351



Image Attachment: R02.jpg (29/10/2008 19:50, 88.15 KB) / Download count 685
http://www.hkbws.org.hk/BBS/attachment.php?aid=2352

Author: kmatthew    Time: 30/10/2008 17:04

I can't see the first set of photos, but the second set looks like a Juv. It shows nearly the same features as our HK bird. The only problem I have with it is it's bill, which look a slight bit over sized... Any other opinions??
Author: HFCheung    Time: 30/10/2008 19:19

According to the criteria given by Paul, on this bird the tail is too round, the primary projection is not long, and also the flank is not enough white.  I would go for Brown Shrike.

HF Cheung



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