Scottish Crossbill - Yes? No? Never? (1 Viewer)

[Gastronaut]

What's the current consensus on Scottish Crossbill? Does it exist? Did it ever exist? Were they just parrot crossbills all along? I remember these points were being debated some years ago but not whether everyone reached agreement.

I've tried checking the official British list online, it appears to still be there in cat A, but why do they have to make it so hard to check? Maybe I just followed the wrong links, to links, to links ...... only to end up at a hideous page that breaks and scrolls all over the place. Is there still a published list anywhere that is simply a list of names?

 

[Hotspur]

Officially it is still an extant concern but a recent SOC paper outlines that calls are not diagnostic and as there is complete overlap of biometrics with Parrot and Common Crossbill. Their position is here:

Identification of Scottish and Parrot Crossbills

SBRC position on Scottish Crossbill - update March 2022 Following analysis and consideration of the most recent findings on the use of the "type C" excitement call to identify Scottish Crossbill, as described below on the webpage, SBRC has concluded that the species can no longer be identified...

www.the-soc.org.uk

 

[Mono]

I think it all dates back to the early days of the British List when folk were desperate to have a British endemic. The early British Birds have lots of articles where people try to delineate British subspecies and they force those into full species status.

 

[Larry Sweetland]

I wonder if the only reason it's still a species is because no-one's written a paper yet proposing to lump it? Is that the case or not?

 

[Farnboro John]

I think it all dates back to the early days of the British List when folk were desperate to have a British endemic. The early British Birds have lots of articles where people try to delineate British subspecies and they force those into full species status.

I heard, way back in the mists of time (and I don't know whether dates match or anything) that the genesis of Scottish Crossbill followed immediately on the loss of Red Grouse as an endemic species due to lumping with Willow Grouse. That would gel well with the desperation aspect.

John

 

[Welsh Peregrine]

All the evidence seems to indicate that even if “Scottish Crossbill” did exist as a real biological entity, there is no way to identify it nowadays! The name “scotica” is attached to a preserved specimen, with no diagnostic DNA sequences known, and the “best” diagnostic feature, voice, being unknown for this specimen, (as well as apparently being changeable during an individual’s lifetime).

 

[DMW]

I think it all dates back to the early days of the British List when folk were desperate to have a British endemic. The early British Birds have lots of articles where people try to delineate British subspecies and they force those into full species status.

I'm not sure that is the case here at all. Scottish Crossbill was described as a subspecies of Common Crossbill in 1904 (by a German), and elevated to species status in 1977 (by a Dutchman). In the intervening years, debate seemingly focused on whether it should be included in Common or Parrot Crossbill.

 

[James Lowther]

Regardless of the strengths of the arguments on either side, there is complete consensus across the different major checklists that Scottish crossbill is still a species. As far as I know there have been no proposals to change this status in any of the lists. I think there is probably some truth to the idea that nothing will change without a published paper suggesting the status quo needs changing.
Cheers
James

 

[James Lowther]

What's the current consensus on Scottish Crossbill? Does it exist? Did it ever exist? Were they just parrot crossbills all along? I remember these points were being debated some years ago but not whether everyone reached agreement.

I've tried checking the official British list online, it appears to still be there in cat A, but why do they have to make it so hard to check? Maybe I just followed the wrong links, to links, to links ...... only to end up at a hideous page that breaks and scrolls all over the place. Is there still a published list anywhere that is simply a list of names?

Simple format list here

https://bou.org.uk/wp-content/uploads/2023/01/BOU_British_List_10th-and-55th_IOC12_2_Cat-F-1.pdf

James

 

[Gastronaut]

Simple format list here

https://bou.org.uk/wp-content/uploads/2023/01/BOU_British_List_10th-and-55th_IOC12_2_Cat-F-1.pdf

James

Thank you

 

[Gastronaut]

Another question, sorry I really haven't been paying attention, what's the status of parrot crossbill in the UK? Are the 'scottish' crossbills in the Caledonian forest back in the 1980s now thought to have been parrots?

just not on the official list 😉

 

[Paul Chapman]

This article may well help or not....

Corsican Crossbills are brilliant. Enormous bills. I suspect a subspecies of Scottish? 😀

Attached a Corsican Crossbill pic...

 

[jurek]

Given splitting subspecies with smaller and smaller differences over the years, there is now a bird species which has no differences whatsoever.

Loch Ness monster would at least have unambiguous and significant differences from a floating tree log if studied well.

 

[Andy Adcock]

+-

All the evidence seems to indicate that even if “Scottish Crossbill” did exist as a real biological entity, there is no way to identify it nowadays! The name “scotica” is attached to a preserved specimen, with no diagnostic DNA sequences known, and the “best” diagnostic feature, voice, being unknown for this specimen, (as well as apparently being changeable during an individual’s lifetime).

So, by extension, neither is Parrot so the birds in the irruption a few years ago should be Crossbill sp unless someone recorderd the excitement call?

 

[opisska]

What's wrong with Parrot Crossbill? Even if there is some overlap, there are surely individuals with beak proportions far outside normal Crossbill range and thus easily IDed as a different species.

 

[Welsh Peregrine]

What's wrong with Parrot Crossbill? Even if there is some overlap, there are surely individuals with beak proportions far outside normal Crossbill range and thus easily IDed as a different species.

Agreed easily identifiable as different, however quite possibly not actually a species under some taxonomic concepts!

 

[Farnboro John]

Agreed easily identifiable as different, however quite possibly not actually a species under some taxonomic concepts!

Also agreed: moreover even from Andy's own post there is a known call difference attributable to a properly documented bird - not at all the same situation as "Scottish Crossbill" which is long past its use-by date.

John

 

[Gastronaut]

This article may well help or not....

Corsican Crossbills are brilliant. Enormous bills. I suspect a subspecies of Scottish? 😀

Attached a Corsican Crossbill pic...

Thanks for this Paul, was indeed helpful.

So, if I've understood it correctly (slim chance), 'Scottish' Crossbill is a good ESU but not strictly distinct under the various definitions of species, not even if you chase them with a pot to gather up poop.

And to answer my own question from my second post, in short, yes.
When I was looking for Scottish Crossbills in the Spey valley back in the early 80's I was using info from the book Highland Birds by D. Nethersole-Thompson (which I always used to think was a great read, back in the days when I could read a book without falling asleep). This suggested that as well as the big bills and funny calls, you could readily tell the Scottish Crossbills apart because they hung out in the Abernethy Forest eating from Scots Pine cones, whereas Common Crossbills would be in the plantations eating from Larch. According to this paper though, those Abernethy birds are now thought to be Parrot Crossbills, or at least they have been since the irruption year of 1982. This might well explain why when I saw some (in around '84 or '85) I thought they were quite noticeably different, more obvious than I was expecting, they looked just like the Parrot Crossbills I'd seen in Derbyshire in '82. The long and short of it though is I think I've just lost a tick on my British list.

 

[Owene]

All of this makes me glad that when I was up in speyside a few years back I saw a clear Parrot crossbill and didn't enter into the mire of scotsbill at all

 

[jurek]

What's wrong with Parrot Crossbill?

That it and Scottish Crossbill are genetically identical to Common Crossbill. Which means that they constantly interbreed with Common Crossbills.

It is now known that beak size of finches is controlled by few genes and can be selected and change within few generations, and that calls are partially learned.

Crossbill research would make an interesting study of bad practices in science. Notorious is cherry-picking arguments and publications for versus against the split. Another is selection bias. 20. century ringing manuals report many intermediate individual crossbills, but 21. century birder records and photos show almost exclusively classic Common and classic Parrot Crossbills. Intermediates are selectively not reported.

It would be absolutely OK to twitch Scottish and Parrot Crossbills, if somebody made a twitching list of bird forms, but not pretended it is a list of species.