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        Discussion Area 討論區 >> Photo Gallery 相片分享 I >>  Common Buzzard 普通鵟
        
(Message started by: KK Hui on Jan 17^th, 2004, 8:09pm)

Title: Common Buzzard 普通鵟
Post by KK Hui on Jan 17^th, 2004, 8:09pm

080 Common Buzzard 普通鵟
Mai Po Nature Reserve 米埔自然保護區
17/1/2004
EOS-10D, EF600/4L + EF1.4x
Evaluative @ -1/3, ISO 200
http://www.hkbws.org.hk/fileServer/PhotoG/kkhui/kkhui_22.jpg

An Upland Buzzard, I think?! ::)

KK Hui ARPS
www.geocities.com/kkhui_001

Title: Re: Upland Buzzard
Post by Mike Turnbull on Jan 18^th, 2004, 12:36am

This could be Common Buzzard. You really need to see the upperside to be able to decide if it could be Upland.

Mike Turnbull

Title: Re: Upland Buzzard
Post by KK Hui on Jan 18^th, 2004, 9:43am

No, I don't have a photo showing its upper wing ...

The reason why I think it's a Upland is its very pale tail feather and the thick trailing edge to its wings ::)

KK Hui ARPS
www.geocities.com/kkhui_001

Title: Re: Upland Buzzard
Post by Mike Turnbull on Jan 18^th, 2004, 2:20pm

Pale, unmarked underside of tail and dark trailing edge of underwing are both features which are very commonly seen in East Asian Common Buzzards. To identify an Upland you need to be sure it is larger, longer-winged and longer-tailed (more "eagley" jizz), and that it shows a white patch on the upperside of the primaries that is more obvious than is ever seen on Common. The upperside should also show a contrast between a dark rump and a paler upperside to the tail.

I personally have very little experience of Upland in the field, only one or two distant possibles. Because both they and Common Buzzard are so extremely variable, Upland is clearly very difficult to identify without plenty of experience in an area where they are numerous.

Birds might be identifiable from excellent photos like this, if they showed the upperside. It is really great to have access to photos like these as good as this. It's almost as good as having access to a skin collection. Perhaps we could set up some kind of organised archive of shots like this?

Btw, Upland Buzzard was briefly on the HK List, and a description of one was published in the 1991 HKBR. However, that record was later found not acceptable as a first for HK on subsequent re-examination and the species was removed from the List. Not to say we couldn't get one though!

Mike Turnbull

Title: Re: Upland Buzzard
Post by KK Hui on Jan 18^th, 2004, 2:55pm

Thank you, Mike, for your additional information. This is both interesting and confusing to say the least ...

It just shows that even with photo, identification of certain birds are far from easy let alone just see it for a brief moment through the binoculars or field scope. This leads me to ponder some of the birders observation records which are seldomly submitted with proof of photos. Unless of course the birder in question is a reputable one and fully experienced!!! ;D ::) ;D

To me photography and birding are inseparable. Any thoughts, any one?

KK Hui ARPS
www.geocities.com/kkhui_001

Title: Re: Upland Buzzard
Post by xyz_ps on Jan 18^th, 2004, 3:26pm

on 01/18/04 at 14:20:51, Mike Turnbull wrote:

Birds might be identifiable from excellent photos like this, if they showed the upperside. It is really great to have access to photos like these as good as this. It's almost as good as having access to a skin collection. Perhaps we could set up some kind of organised archive of shots like this?

Absolutely agreed!
A database can be set up and the photos of this level of quality can be used to help others to identify birds. Typical features for identification of that particular species might be marked and indiciated on the photos so it can make great help novice like me~ ;)

Title: Re: Upland Buzzard
Post by Mike Turnbull on Jan 19^th, 2004, 12:00am

"It just shows that even with photo, identification of certain birds are far from easy let alone just see it for a brief moment through the binoculars or field scope. This leads me to ponder some of the birders observation records which are seldomly submitted with proof of photos. Unless of course the birder in question is a reputable one and fully experienced!!!"

A few points about records and photo evidence, and photos as ways of identifying birds.

First of all, "the brief moment" point: really no record should be either submitted or accepted on really brief views unless (a) the bird is unmistakable and (b) there really is no reason to think the observer may for any reason have made a mistake.

Secondly, the implied point about the desirability of proof in the form of photos - yes, it's nice, but for a variety of reasons you aren't going to get it. Biggest of these reasons is that the majority of birders aren't carrying expensive, high spec cameras, and even if they were, you can't usually bird and take photos. Therefore we rely on, as you suggest, expertise and experience (which produce wisdom and judgement) - and fully documented records.

Finally, we have to recognise the occasional limitations of photos, perhaps especially of birds in flight: they sometimes do not capture structure/jizz very well, each individual picture being just a snapshot from one angle. If there is a diagnostic feature and the camera captures that, that's great; if not, however, we're just left with a frozen, apparently inconclusive view such as here, where, as I said earlier, the two species really are phenomenally variable, in terms of the simple, observable plumage features we are usually able to use to identify species - I think this level of difficulty is essentially why the earlier record was simply considered not quite unacceptable on review, but I'm guessing there, as I was not part of that decision.

I should also add that my earlier comments and these are just intended as a contribution to a very encouraging phenomenon in which more and more birders in HK are beginning to be much better informed and more confident in bird identification issues. The publication of photos like this plays a much more important part in that process than comments like these, as long as the reasons for the establishing the identity of the birds in the photos are discussed as fully as possible.

Please keep posting the pictures! We love to look at them and to discuss them!

Mike Turnbull