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Paux 10/01/2021 16:27

White Wagtail ocularis 白鶺鴒

09.01.2021
Shek Kong Catchment
[attach]40774[/attach]
[attach]40775[/attach]

Roman 10/01/2021 19:46

This is likely M.a.lugens rather than ocularis

happyman 11/01/2021 11:48

Is that M. a. lugens comes with a black back while M. a. ocularis comes with a grey back?

cgeoff 11/01/2021 15:08

Why's that Roman?

Roman 11/01/2021 15:21

[quote]Original posted by [i]cgeoff[/i] at 11/01/2021 15:08 [url=http://www.hkbws.org.hk/BBS/redirect.php?goto=findpost&pid=85959&ptid=29621][img]http://www.hkbws.org.hk/BBS/images/common/back.gif[/img][/url]
Why's that Roman? [/quote]
From the pics we can see the thick rear part of eye strip, and the whitish greater converts.

[[i] Last edited by Roman at 11/01/2021 15:22 [/i]]

Paux 11/01/2021 23:37

Roman, thank you for your comments. I have gone through a couple of relevant articles found on the net. As the bird in question was probably a 1st year juvenile, it will be even more difficult to ID; a juv. ocularis looks very alike a juv. lugens. For the time being, I am inclined to think this was a White Wagtail ocularis as the greater coverts were darker than those of a lugens. Nevertheless, more expert opinions will be much appreciated as I am just an ordinary birder.

happyman 12/01/2021 07:42

Not sure if the diagram below would do any help?

ajohn 5/02/2021 10:32

I'm sure this is [i]ocularis[/i] rather than [i]lugens[/i].
- I don't think the eyestripe broadens as much as expected for [i]lugens[/i], and is actually quite narrow still where it meets the black nape. The eyestripe on [i]ocularis[/i] is normally slightly wider behind the eye than in front, but no to the same extent as [i]lugens[/i] and without showing the 'step' in broadness that [i]lugens[/i] commonly shows.
- The upperparts are very pale grey - although first year [i]lugens[/i] can have grey upperparts, they are not usually this pale. On pale [i]lugens[/i] the crown would not normally be black as it is on this bird.  
- Importantly, the rump is also grey with only the centres of the longest upper tail coverts black - [i]lugens[/i] should show more black on the rump than this.
- The greater coverts have white fringes but this is typical of [i]ocularis[/i]. I would expect [i]lugens[/i] to show more white than this in the greater coverts, but also in the median coverts (usually mostly white with just a narrow dark streak on the shaft) and tertials, and possibly even the primaries and secondaries. The lesser coverts would normally be darker than this on a black-backed subspecies like [i]lugens[/i], at least with black feather centres and often mostly black.

Roman 5/02/2021 11:43

[quote]Original posted by [i]ajohn[/i] at 5/02/2021 10:32 [url=http://www.hkbws.org.hk/BBS/redirect.php?goto=findpost&pid=86125&ptid=29621][img]http://www.hkbws.org.hk/BBS/images/common/back.gif[/img][/url]
I'm sure this is ocularis rather than lugens.
- I don't think the eyestripe broadens as much as expected for lugens, and is actually quite narrow still where it meets the black nape. The eyestripe on  ... [/quote]
Thanks John, This is helpful again.
I thought I understand this two race but seems I am definitely wrong on that bird, even I have seen this individual and watching it careful, this is important to check it part by part.
Could you check the below bird at Santin I was identified as lugens previously, I think it still match the points after your advice, thanks.

[[i] Last edited by Roman at 5/02/2021 11:46 [/i]]

Paux 6/02/2021 12:14

John, thank you for your very detailed analysis.

ajohn 14/02/2021 14:30

[quote]Original posted by [i]Roman[/i] at 5/02/2021 11:43 [url=http://www.hkbws.org.hk/BBS/redirect.php?goto=findpost&pid=86126&ptid=29621][img]http://www.hkbws.org.hk/BBS/images/common/back.gif[/img][/url]

Thanks John, This is helpful again.
I thought I understand this two race but seems I am definitely wrong on that bird, even I have seen this individual and watching it careful, this is important to c ... [/quote]

This bird also looks like [i]ocularis[/i] to me - typical head pattern, pale grey back, grey lesser coverts, not much white in primaries/secondaries. The white in the greater & median coverts is a bit more extensive than on the first post, but you can see the dark centres to the GC and this pattern is well within range for [i]ocularis[/i].

Roman 14/02/2021 15:06

[quote]Original posted by [i]ajohn[/i] at 14/02/2021 14:30 [url=http://www.hkbws.org.hk/BBS/redirect.php?goto=findpost&pid=86158&ptid=29621][img]http://www.hkbws.org.hk/BBS/images/common/back.gif[/img][/url]


This bird also looks like ocularis to me - typical head pattern, pale grey back, grey lesser coverts, not much white in primaries/secondaries. The white in the greater & median coverts is a bit more ... [/quote]
Thanks, though lugens are overlooked in HK, but in fact seems it's over reported by me, I am afraid I never seen lugens in HK.
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