RBA have just announced that the DNA results have shown the said bird to be a Pied Flycatcher.
Quite suprising news! Unless of course, the main objective was first of all to rule Atlas in or out before further tests are carried out to reveal a possible Hybrid?
-- Edited by Phil Owen on Saturday 12th of May 2012 01:14:03 PM
Mike Passant said
Fri May 11 8:45 PM, 2012
- An interesting discussion this, which draws me into another aspect, i.e. that of accelerated speciation via hybridisation.
The last time I was in N. Africa (many years ago) there was of course no such thing as "Atlas Flycatcher", so I can claim no experience of this form at all.
This may be a bit over simplistic, but looking at the ranges of Pied Flycatcher and Collared Flycatcher in my older "Collins" I notice that there is an area of overlap around Algeria/Tunisia. Atlas Flycatcher could well have evolved as a direct consequence of interbreeding in this overlap zone, where the resultant hybrid form might adapt and prosper better than either of the original parent forms, and thus enjoy a "shorter cut" towards becoming a full species.
I suggest that where this happens within a relatively short period of time, there might still remain an unusually high degree of variation in the DNA of individual Atlas Flycatchers, with some individual bias towards the DNA of either of the original parent species. This could also of course manifest itself in certain plumage characteristics.
All this makes identification with certainty no easy matter, especially if the parameters of acceptable variation within this relatively recently described species have not yet been formulated.
Regards, Mike P.
JasonAtkinson said
Mon May 7 8:14 PM, 2012
If only these things were that simple Rory.
Cheers Jason
Rory Newton said
Mon May 7 1:03 PM, 2012
Ok, thanks for clearing that up, I didn't realise that Vagrant recording was so complicated! I'd have thought they would be happy to put it on the British list anyway!
-- Edited by Rory Newton on Monday 7th of May 2012 01:09:11 PM
Ian McKerchar said
Mon May 7 2:04 AM, 2012
As improbable as Mamora's Jase? It has been mooted as a possible vagrant by those far better informed than I but statistically it's surely less likely than the aforementioned hybrid possibility anyway.
With you on the DNA pal; hence my earlier comment. Don't fancy lugging round my 'field DNA testing kit' with me too when I go out either. As if gulls weren't bad enough
JasonAtkinson said
Mon May 7 1:45 AM, 2012
Rory Newton wrote:
Ian McKerchar wrote: I am pleased that you find this bird 'completely obvious' Rory, so please feel free to enlighten me as to what makes it definately an Atlas Flycatcher
Firstly, and mainly the white patch on the birds face is so large(and in one single spot), which is far Larger than any other of the Black and White flycatchers, and so well defined that I'd have thought this would have clearly abolished any doubt of the bird being a hybrid. Anyway, which species is the bird supposed to be a hybrid with?
I must admit I chuckled slightly with your ' completely obvious' comment? I was going to reply but Ian pretty much said what I was. The obvious presumption with regards hybrid would be Collared x Pied. In the hand analysis (which is more productive for ID reasons) has been unable to determine what it is, so it is patently obvious it isn't 'completely obvious'. The prospect of ID via DNA has the potential to really open a can of worms. For this reason alone I haven't made the attempt for I must say is a rather smart individual. What i must add is is Atlas Flycatcher really identified as a possible/potential vagrant in the UK? A fairly short range migrant within its given range and yes they have appeared in Italy and Spain, but another 1200 miles (at least) further north than the Spanish bird? Not impossible but improbable I think.
Cheers Jason
Rory Newton said
Mon May 7 12:30 AM, 2012
Ian McKerchar wrote: I am pleased that you find this bird 'completely obvious' Rory, so please feel free to enlighten me as to what makes it definately an Atlas Flycatcher
Firstly, and mainly the white patch on the birds face is so large(and in one single spot), which is far Larger than any other of the Black and White flycatchers, and so well defined that I'd have thought this would have clearly abolished any doubt of the bird being a hybrid. Anyway, which species is the bird supposed to be a hybrid with?
sid ashton said
Sun May 6 7:02 PM, 2012
Rory Newton wrote:
Hi, Can anyone please tell me why Rare Bird Alert, Birdguides and websites of a similar nature are still announcing the Flamborough Head Atlas Flycatcher as 'Possible Atlas Flycatcher' when it is completley obvious that it is an Atlas Fly? Why, after catching and examining the bird, are the BOU still waiting for DNA results to confirm the birds identity? Thanks, Rory
It's not "completely obvious" to a lot of people Rory, that's why there is still doubt
Tony Coatsworth said
Sun May 6 6:08 PM, 2012
Is that worth 2 ticks then ??
Ian McKerchar said
Sun May 6 5:56 PM, 2012
Rory Newton wrote:
Firstly, and mainly the white patch on the birds face is so large(and in one single spot), which is far Larger than any other of the Black and White flycatchers, and so well defined that I'd have thought this would have clearly abolished any doubt of the bird being a hybrid.
Unfortunately not Rory.
No one is actually saying this is a hybrid by the way, just that in such an extreme vagrant context it should be ruled out due to the possibility of potentially extremely similar hybrid offspring. As for which species may be involved in parenting such a hybrid Collared x Pied is perhaps most likely.
-- Edited by Ian McKerchar on Sunday 6th of May 2012 06:41:30 PM
Ian McKerchar said
Sun May 6 2:09 PM, 2012
Rory Newton wrote:
Hi, Can anyone please tell me why Rare Bird Alert, Birdguides and websites of a similar nature are still announcing the Flamborough Head Atlas Flycatcher as 'Possible Atlas Flycatcher' when it is completley obvious that it is an Atlas Fly? Why, after catching and examining the bird, are the BOU still waiting for DNA results to confirm the birds identity? Thanks, Rory
I am pleased that you find this bird 'completely obvious' Rory, so please feel free to enlighten me as to what makes it definately an Atlas Flycatcher, especially as eminent birders with considerable field experience of the species are clearly and probably quite rightly unsure or at least non-committal of its true identity.
The spectre of hybrids is a serious issue and one which only DNA may offer an answer; that I do know. Possibly lots to learn with this bird but then again the results may not be as 'positive' as we hope; and I don't just mean about it's identification
Unfortunately, I have no field experience of Atlas Flycatcher and so can add nothing I'm afraid.
-- Edited by Ian McKerchar on Sunday 6th of May 2012 02:12:10 PM
Nick Isherwood said
Sat May 5 11:51 PM, 2012
I think there's some debate about the bird being a possible hybrid. Only a DNA analysis can confirm it's true identity.
Rory Newton said
Sat May 5 10:27 PM, 2012
Hi, Can anyone please tell me why Rare Bird Alert, Birdguides and websites of a similar nature are still announcing the Flamborough Head Atlas Flycatcher as 'Possible Atlas Flycatcher' when it is completley obvious that it is an Atlas Fly? Why, after catching and examining the bird, are the BOU still waiting for DNA results to confirm the birds identity? Thanks, Rory
RBA have just announced that the DNA results have shown the said bird to be a Pied Flycatcher.
Quite suprising news! Unless of course, the main objective was first of all to rule Atlas in or out before further tests are carried out to reveal a possible Hybrid?
-- Edited by Phil Owen on Saturday 12th of May 2012 01:14:03 PM
- An interesting discussion this, which draws me into another aspect, i.e. that of accelerated speciation via hybridisation.
The last time I was in N. Africa (many years ago) there was of course no such thing as "Atlas Flycatcher", so I can claim no experience of this form at all.
This may be a bit over simplistic, but looking at the ranges of Pied Flycatcher and Collared Flycatcher in my older "Collins" I notice that there is an area of overlap around Algeria/Tunisia. Atlas Flycatcher could well have evolved as a direct consequence of interbreeding in this overlap zone, where the resultant hybrid form might adapt and prosper better than either of the original parent forms, and thus enjoy a "shorter cut" towards becoming a full species.
I suggest that where this happens within a relatively short period of time, there might still remain an unusually high degree of variation in the DNA of individual Atlas Flycatchers, with some individual bias towards the DNA of either of the original parent species. This could also of course manifest itself in certain plumage characteristics.
All this makes identification with certainty no easy matter, especially if the parameters of acceptable variation within this relatively recently described species have not yet been formulated.
Regards,
Mike P.
Cheers
Jason
-- Edited by Rory Newton on Monday 7th of May 2012 01:09:11 PM
With you on the DNA pal; hence my earlier comment. Don't fancy lugging round my 'field DNA testing kit' with me too when I go out either. As if gulls weren't bad enough
I must admit I chuckled slightly with your ' completely obvious' comment? I was going to reply but Ian pretty much said what I was. The obvious presumption with regards hybrid would be Collared x Pied.
In the hand analysis (which is more productive for ID reasons) has been unable to determine what it is, so it is patently obvious it isn't 'completely obvious'. The prospect of ID via DNA has the potential to really open a can of worms. For this reason alone I haven't made the attempt for I must say is a rather smart individual.
What i must add is is Atlas Flycatcher really identified as a possible/potential vagrant in the UK? A fairly short range migrant within its given range and yes they have appeared in Italy and Spain, but another 1200 miles (at least) further north than the Spanish bird? Not impossible but improbable I think.
Cheers
Jason
Firstly, and mainly the white patch on the birds face is so large(and in one single spot), which is far Larger than any other of the Black and White flycatchers, and so well defined that I'd have thought this would have clearly abolished any doubt of the bird being a hybrid.
Anyway, which species is the bird supposed to be a hybrid with?
I am pleased that you find this bird 'completely obvious' Rory, so please feel free to enlighten me as to what makes it definately an Atlas Flycatcher, especially as eminent birders with considerable field experience of the species are clearly and probably quite rightly unsure or at least non-committal of its true identity.
The spectre of hybrids is a serious issue and one which only DNA may offer an answer; that I do know. Possibly lots to learn with this bird but then again the results may not be as 'positive' as we hope; and I don't just mean about it's identification
Unfortunately, I have no field experience of Atlas Flycatcher and so can add nothing I'm afraid.
-- Edited by Ian McKerchar on Sunday 6th of May 2012 02:12:10 PM
Can anyone please tell me why Rare Bird Alert, Birdguides and websites of a similar nature are still announcing the Flamborough Head Atlas Flycatcher as 'Possible Atlas Flycatcher' when it is completley obvious that it is an Atlas Fly? Why, after catching and examining the bird, are the BOU still waiting for DNA results to confirm the birds identity?
Thanks,
Rory