Original posted by 星魚 at 6/01/2014 14:28
Yellow Wagtail
As a beginner, I am often confused between grey and yellow wagtails. Could this one be a grey wagtail instead? Author: louislee Time: 6/01/2014 21:11
I believe the two can be distinguished by the primaries Author: irsychan Time: 6/01/2014 22:56
Quote:
Original posted by louislee at 6/01/2014 21:11
I believe the two can be distinguished by the primaries
Thank you. However, I thought the yellow wagtails have black legs and yellow underparts.
The photo seems show that the legs are not black? Author: irsychan Time: 7/01/2014 08:01
After examining the colour of the legs more closely it may be black partly covered by mud. Could this be first winter Yellow Wagtail? Would be interested to learn how to distinguish between yellow and grey wagtails from the primaries as this is not mentioned in literature I got. Author: ajohn Time: 7/01/2014 09:02
This is a first-winter Yellow Wagtail, subspecies macronyx.
Grey and Yellow Wagtails can be separated in a number of ways. One thing to remember is that first winter Yellow Wagtails in Hong Kong are mostly grey & white when they arrive and only gradually moult into the green and yellow breeding plumage.
Head pattern - Grey Wagtail always shows a clear, white, narrow supercilium (although some Yellow Wagtail, especially tschutschensis, can be similar)
Leg colour - black in Yellow Wagtail, pinkish in Grey Wagtail (note that the legs on this bird are stained by mud)
Undertail - Grey Wagtail has yellow undertail coverts throughout the year, many Yellow Wagtails are whitish
Upperparts - Grey Wagtail is always grey above, usually with obviously black wings. Any green on the upperparts indicates a Yellow Wagtail
Rump - Grey Wagtail has a yellowish rump, Yellow Wagtail is grey or green (not visible on this bird)
Tail - Grey Wagtail usually looks very long-tailed, Yellow is usually shorter-tailed
Wing-bars - In flight Grey Wagtail always shows a broad white wing bar formed from white bases to the primaries/secondaries, which Yellow Wagtail lacks. On the ground Yellow often has yellowish wingbars from the tips of the greater coverts.
Habitat - Grey Wagtail is usually in fast-flowing streams, Yellow Wagtail is usually in wet fields or fishpond bunds. This isn't 100% reliable, but is a useful guide.
I hope that helps. Author: irsychan Time: 7/01/2014 13:37
Thank you ajohn. Your detailed advice is very helpful indeed.
Normally it isn't that difficult to differentiate but this first winter plumage is a bit tricky. Author: bws1114 Time: 11/01/2014 01:02
Thx for ajohn & irsychan discussion to distinguish between Grey & Yellow Wagtail, this is also my problem in classifying them. From now, I can check the details description fm ajohn to compare among them!!
[ Last edited by bws1114 at 11/01/2014 01:04 ]
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