-
Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.
Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
Juvenile Wagtail UK (1 Viewer)
- Thread starter Wizzle
- Start date
Jane Turner
Well-known member
No - its a Pied
Jane Turner
Well-known member
Tib78
Well-known member
I would rely more on location and time of the year to ID this bird. Granted, it looks more typical of Pied with that rump. But some juv alba look essentially identical.
The funny thing is: UK birders look for an all grey rump (or so) before even considering the possibility of a White wag; on the other hand, where I live (near Paris) you won't get a Pied accepted unless the rump is extensively blackish.
The funny thing is: UK birders look for an all grey rump (or so) before even considering the possibility of a White wag; on the other hand, where I live (near Paris) you won't get a Pied accepted unless the rump is extensively blackish.
Jane Turner
Well-known member
That doesn't surprise me Tib... and it makes sense to default to the expected bird in the overlap zone.
Yes agree and on that basis I immediately assumed Pied but then remembered that there were (or claimed to be) lots of Whites about this spring.
Tib78
Well-known member
Yes but in winter Pied wagtail is just a minor rarity where I live.
How would you ID the 2 birds attached? Both found in the same flock in january this winter.
Attachments
Jane Turner
Well-known member
Ist w fem Pied - if they were here Tib, though the flanks look a bit clean
Tib78
Well-known member
Well I kind of agree. I would say the first bird has definitely some Pied genes in it. But can it be considered a safe Pied? I guess not (at least that's the opinion of the local recorder with whom I discussed the bird).
The second bird I am not too sure about. It was darker than the other birds in the flock (excepted the first bird I posted of course), which is why I picked it up at first glance. Could it just be a dark White wag with a blackish lower rump?
Things get really complicated when you take account of the possibility of hybrids/intergrades.
Tib,
The first bird appears to have a large number of juvenile greater coverts still, and looks identical to 1st winter Pied Wagtail to my eyes.
The second bird, another first winter, indeed has solid blackish rump, which is outside of the variation seen in alba. It also has rather dark olive-grey upperparts, so it is definitely more like Pied than White Wag.
Oddly enough, intergrades are never recorded in autumn. Presumably, that is because their plumage looks identical to that of pure birds, alas... In spring, mixed characters become a bit more obvious, especially when you can reliably sex the bird (e.g. when it is singing, or is part of a pair).
So, applying very strict criteria in autumn/winter is a bit futile. I think it is simply impossible to distinguish between pure birds and intergrades in the field at that time of year. No matter how strict your criteria, you can still not be 100% sure. Even with DNA it would be impossible.
With such birds (and with Dusky Thrushes, Black-throated Thrushes,...) maybe we have to accept that we are field birders and that there will always be a slight element of uncertainty. Nobody ever said that ornithology is an exact science.
The first bird appears to have a large number of juvenile greater coverts still, and looks identical to 1st winter Pied Wagtail to my eyes.
The second bird, another first winter, indeed has solid blackish rump, which is outside of the variation seen in alba. It also has rather dark olive-grey upperparts, so it is definitely more like Pied than White Wag.
Oddly enough, intergrades are never recorded in autumn. Presumably, that is because their plumage looks identical to that of pure birds, alas... In spring, mixed characters become a bit more obvious, especially when you can reliably sex the bird (e.g. when it is singing, or is part of a pair).
So, applying very strict criteria in autumn/winter is a bit futile. I think it is simply impossible to distinguish between pure birds and intergrades in the field at that time of year. No matter how strict your criteria, you can still not be 100% sure. Even with DNA it would be impossible.
With such birds (and with Dusky Thrushes, Black-throated Thrushes,...) maybe we have to accept that we are field birders and that there will always be a slight element of uncertainty. Nobody ever said that ornithology is an exact science.
Tib78
Well-known member
Thanks Peter for your input and for a balanced answer.
And thank you Jane for having a go.
To me, this is quite reassuring because I had IDed both birds as Pied wag in the field (and I didn't change my mind when reviewing my pics latter). Glad I posted them. Of course I heard what you said Peter about (un)certainty.
I guess I'll have to discuss those birds again with the local recorder...
Thanks again.
And thank you Jane for having a go.
To me, this is quite reassuring because I had IDed both birds as Pied wag in the field (and I didn't change my mind when reviewing my pics latter). Glad I posted them. Of course I heard what you said Peter about (un)certainty.
I guess I'll have to discuss those birds again with the local recorder...
Thanks again.
