BLI recognised Loxia scotia no longer as species (2 Viewers)

[Melanie]

http://www.birdlifeforums.org/WebX?13@@.2cba6aeb

 

[Richard Klim]

I've always felt that recognition of Loxia scotica Scottish Crossbill was something of an anomaly (driven partly by conservation interests, and perhaps even the desire in Britain to have an least one endemic species!). It will be interesting to see if there is any reaction from BOURC.

Actually it's rather ironic that BirdLife has chosen "to follow the approach of the AOU in recognising one species of Red Crossbill" just when AOU-NACC is considering a proposal to recognise L sinesciuris South Hills Crossbill.

But although BirdLife has now lumped it with L curvirostra Common/Red Crossbill, perhaps there is an alternative case for its treatment as a race of L pytyopsittacus Parrot Crossbill (eg, as per UK400 Club)?

Richard

 

[Jos Stratford]

perhaps even the desire in Britain to have an least one endemic species...

Start a 'Liberate the Red Grouse' campaign to replace it?

 

[Richard Klim]

Start a 'Liberate the Red Grouse' campaign to replace it?

Why not indeed? The cold war's over - there shouldn't be any objections to a left-leaning species in these more enlightened times.

It would certainly provide a more safely tickable substitute!

Richard

 

[l_raty]

Why not indeed? The cold war's over - there shouldn't be any objections to a left-leaning species in these more enlightened times.

It would certainly provide a more safely tickable substitute!

But this doesn't coincide with the main phylogeographic break in Willow Grouse, which IIRC is between NE America and the rest of the world...

L -

 

[chris butterworth]

I was wondering about the link with the AOU's approach to "Red" Crossbill ( I've also wondered about a lot of their recent "splits", but thats besides the question ). Perhaps I shouldn't have read this thread as I finally got to grips with Crossbills in Scotland this year and definitly got "Scottish". Bu**er.
Chris

 

[jurek]

I've always felt that recognition of Loxia scotica Scottish Crossbill was something of an anomaly (driven partly by conservation interests, and perhaps even the desire in Britain to have an least one endemic species!). It will be interesting to see if there is any reaction from BOURC.

Cannot agree more! Especially now that we know that there is no genetic difference at all between these three crossbills; that Parrot, Scottish and Common crossbills became practically unrecognizable when they breed together in Scotland, and that crossbills trapped in England with measurements fitting Scottish Crossbills are left unidentified.

But although BirdLife has now lumped it with L curvirostra Common/Red Crossbill, perhaps there is an alternative case for its treatment as a race of L pytyopsittacus Parrot Crossbill (eg, as per UK400 Club)?

Unfortunately, genetics says there is no difference. So, no reason to claim that Scottish and Parrot Crossbills are more related to each other than to other crossbills.

Parrot Crossbill is itself on a trajectory to be lumped as a characteristic ecological race of Common Crossbill. Not a common thing, but not unusual either. It would be interesting to hear if Scandinavians did some studies on it vs local Common Crossbills.

So, British flag-waving patriotic birders must satisfy themselves with ticking any of the numerous wonderful endemics found in British overseas territories. Falkland Steamer-Duck ROXXS!!!

 

[Richard Klim]

So, British flag-waving patriotic birders must satisfy themselves with ticking any of the numerous wonderful endemics found in British overseas territories.

Well, they will need to be quick. Regrettably our authorities seem to have little interest in the rapidly deteriorating prospects of the many globally endangered or threatened species in the UK Overseas Territories (UKOTs). :C

Richard

 

[njlarsen]

Cannot agree more! Especially now that we know that there is no genetic difference at all between these three crossbills; that Parrot, Scottish and Common crossbills became practically unrecognizable when they breed together in Scotland, and that crossbills trapped in England with measurements fitting Scottish Crossbills are left unidentified.



Unfortunately, genetics says there is no difference. So, no reason to claim that Scottish and Parrot Crossbills are more related to each other than to other crossbills.

Parrot Crossbill is itself on a trajectory to be lumped as a characteristic ecological race of Common Crossbill. Not a common thing, but not unusual either. It would be interesting to hear if Scandinavians did some studies on it vs local Common Crossbills.

So, British flag-waving patriotic birders must satisfy themselves with ticking any of the numerous wonderful endemics found in British overseas territories. Falkland Steamer-Duck ROXXS!!!

I thought I read somewhere that Common and Parrot Xbills do seem to behave as good biological species, even when they breed in the same areas after invasions. Ignoring such information and lump them would indeed seem odd!

Niels

 

[Daniel Philippe]

Unfortunately, genetics says there is no difference. So, no reason to claim that Scottish and Parrot Crossbills are more related to each other than to other crossbills.

IMHO genetic distance alone is not enough to assign species ranks. In which case the Galapagos finches would be one species only.

 

[bombycilla]

No significant genetic differences have been discovered amongst European Crossbills using the methods that were employed back then (mitochondrial). My understanding is that more work is to be carried out using more refined techniques and differences may then be found for Scottish Crossbill.

Genetics are only part of the picture anyway and should not be exclusive in defining speciation of crossbills (or any other taxa) - lack of genetic differences are often abused by sceptics and anti-splitters !

Parrot Crossbill is not a 'race' of Common Crossbill. It may be related to an ancestral 'common' crossbill form way, way back but to say in 2009 that it is a race of Common Crossbill is total cobblers - it is different biometrically (inc. plumage), has different calls and song, feeds on different conifers and generally breeds assortatively and moults completely asynchronous to curvirostra (where they co-exist). If it is not a 'species' then it sure as heck is acting as one.

The Scottish Crossbill apparently does exist.............it's just some folks don't seem to know which one it is ! See HERE. And HERE.

Bob.

 

[Xenospiza]

With more refined techniques you can find all kinds of differences between populations of all kinds of birds...

I guess it's either one “Red Crossbill” or many... (I quite enjoyed trying to identify an odd-calling crossbill last weekend), but not “Common + Parrot + Scottish”.

 

[Richard Klim]

I guess it's either one "Red Crossbill" or many..., but not "Common + Parrot + Scottish".

Yes, as reflected in AOU's current position (Check-list 7th Edition)...

"Apparently at least nine species, differing in morphology and vocalizations, exist in North America, with some breeding sympatrically and mating assortatively"​

...but sensibly awaiting evidence of the bigger picture before making one-off localised splits (except for the impending decision on sinesciuris!).

Richard

 

[jurek]

Well, Scottish Crossbills are different, but simply not enough to be called a species.

Lack of genetic differences means (for me) that these forms don't exist long and there is no time to accumulate genetic differences. They form when particular conifer seeds occur, and later crossbreed and lump again.

But I think we had similar discussion in another thread.

Fascinating and beautiful birds, anyway.

 

[bombycilla]

They form when particular conifer seeds occur, and later crossbreed and lump again.

Please provide your evidence for this cross breeding. Most studies I have read conclude that crossbills mate (positive) assortatively ! Your theory would also not also explain the 9 ( or 10) Red Crossbill types in the USA that all have different bill morphology ( and even genetic differences I bekieve !).

Your argument is not implausible, but without large amounts of anectodal or scientific data describing cross-breeding on a larger scale that would allow genetic indifference, then it seems unlikely, especially so between Common and Parrot Crossbill.

B.

 

[jurek]

I meant that lack of known genetic differences speaks for the gene flow.

 

[bombycilla]

I meant that lack of known genetic differences speaks for the gene flow.

"Known" being the operative word ! I also have to take issue at your previous statement that Common, Scottish and Parrot Crossbill became "practically unrecognizable" when they breed together in Scotland. Firstly, they do not breed with each other ( cross breed ) as a rule and secondly those working on these species have no trouble differentiating them either by call, plumage or morphology ( jizz).

The Birdlife decision is all the more strange given RSPB are a partner. I can't see RSPB being happy with this stance given all the work to promote Scottish Crossbill as a species.

If the AOU checklist recoginzes 9 species of Red Crossbill in America why are Birdlife quoting that they are following this example ? Am I missing something ?

 

[njlarsen]

If the AOU checklist recoginzes 9 species of Red Crossbill in America why are Birdlife quoting that they are following this example ? Am I missing something ?

I think that is an exaggeration. There is a current proposal to recognize South Hills Crossbill, and the others have been mentioned in papers but not brought before AOU as far as I know.

Niels

 

[Richard Klim]

If the AOU checklist recoginzes 9 species of Red Crossbill in America why are Birdlife quoting that they are following this example ? Am I missing something ?

The current AOU Check-list acknowledges that there are probably many species involved within Red/Common Crossbill, but only formally recognises L curvirostra for now, pending further research:

Apparently at least nine species, differing in morphology and vocalizations, exist in North America, with some breeding sympatrically and mating assortatively (Groth 1988, 1993a, 1993b); however, morphological overlap among some species currently prevents assignment with certainty of some existing type specimens to the groups defined by call types (Groth 1993a). Additional species-level taxa almost certainly exist among the populations outside North America currently assigned to Loxia curvirostra (Groth 1993a).

http://www.aou.org/checklist/north/pdf/AOUchecklistSturn-Estril.pdf (p663)

So it will be interesting to see the result of the pending NACC proposal to recognise L sinesciuris, which would conflict with the policy (so far) of avoiding piecemeal splitting.

Richard

 

[Richard Klim]

...although BirdLife has now lumped it with L curvirostra Common/Red Crossbill, perhaps there is an alternative case for its treatment as a race of L pytyopsittacus Parrot Crossbill...

Actually, BirdLife's own species account for Loxia scotica implied that the latter treatment may be more appropriate:

"Recent work on flight and excitement calls suggest that it can be distinguished from Common Crossbill L. curvirostra but whether it is distinct from Parrot Crossbill L. pytyopsittacus remains unclear."
http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=8877&m=0​

Richard