Monday, May 05, 2008

Wheatears in May - Greenlanders


(c) 2008


Greenlanders
Hi Mick
Very Many thanks for this Mick, sure it will help us all. It certainly helped me last year when I began to get a real grasp and even a few photos, albeit, very poor (might do better this year?), but that is what you need to do to get it in to your mind. I agree Mick, you’ve just got to let a lot of em go, but its all good training and like you Mick I believe there are many more than actually get recorded (my own experience – I’ve never claimed one - even though I know I've had em).

For those that don’t know, Mick is one of our original resident ID experts, now living away from the area – its amazing what the internet can do, to help people to keep in touch. Mick was one of the founder members of the Bradford OG way back in 1987, so he knows Bradford like the back of his hand!!

Dave.

----- Original Message -----
From: Mick Cunningham
To: David Barker
Sent: Monday, April 11, 2005 8:43 AM
Subject: Identifying Greenland Wheatears amongst the Bradford 800

Hi Everyone
Over the last couple of years I have noticed that a lot of the later Wheateras we get show characterisitics of Greenland Wheatear. This is especially so of later arrivals i.e. those due through later in April and into May. So, if you're going to get 800+ birds again this year, it could be worth checking these.

Firstly, a word of caution.
There will be lots of individuals we can't tell because some are indistinguishable and good views are needed, uually with a scope. Also, there are intergrades. Still, the fact that we can't separate these doesn't mean we shouldn't note the ones we can. Importantly, you need to know how to age birds - it's easy once known, especially with males. Male adults have new wings so the ground colour of coverts and flight feathers is black; as black as the face mask. Often these new wings have crisp rusty fringes. 1st Summer males' wings have a worn dull brown ground colour - browner than the face mask and without crisp rusty fringes. Don't confuse this old completely brown wings with the rusty fringing on adults' new wings. The same applies to females though of course the face mask trick doesn't apply.

All this racial ID can be a bit tentative at first but here's what I do.

Worth a look are 'big',buffy, pot-bellied birds with obscene looking pinky fronts extendingfar down flanks and, especially, towards belly between legs - AND a brown suffusion to upperparts, even in full adults. Nominate Northern's are 'less bulky', and pale silvery grey above with amore limited peach bib below that doesn't extend far down and so it has whiter belly and lower flanks.

Greenlands often look short-tailed because the longer wing invades the black tail tip to about 1/4-1/2. Northern's wings don't invade black of tail tip so much and so their tail looks longer.

CRITICALLY - and an absolute must, is the number of primary tips visible in the primaryprojection. There are 5 on Northern and 6 (7 just?) on Greenland. Hence the long wing that ringers get. You need to see the birds back on and still, and need to use a scope or a digicamera.

If I get all of these features, I say 'showing characters of' Greenland. If not I let them go. Sceptics said none of this was possible in the field but I was seeing Greenlands at the same time as ringers caught them at e.g. Wintersett Res. Also, have a look at the BTO migrant atlas and note what it says about flocking behaviour of Greenland Wheatears, their migration route and their stopover strategy as compared to Northen. It'll prove v interesting because it says they come up the west coast in April-May and feed up/flock prior to setting off accross the sea off the West Coast. I think we get these birds when they're pushed over the Pennine spine by westerlies. Have fun!

Mick

2 Comments:

Blogger AndyC said...

Very interseting indeed,I think the adult males that come through about now and some times earlier are imediatly different in jizz and size.(which is apparent immediatly when see one as you have been watching northerns since the first ones in March).Counting the primary tips is not that difficult with these individuals if you have a scope and 6/7 tips are always visible on these large males.I find it a lot more difficult with other ages.
What is the opinion on Stonechats with white rumps that pass through inland in April.?

May 06, 2008 6:56 am  
Blogger Dave Barker said...

Cheers Andy and I agree. Not sure about the Stonechats as I have never seen one with a white rump or looked into it.

I will have a word with Keith M when I see him and post again.

Have seen your notes and photos on Queensbury birds..... interesting stuff!

Dave

May 07, 2008 7:51 pm  

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