Latest IOC Diary Updates (14 Viewers)

[twitcherf]

IOC is leaving a lot of coal in people's stockings this year!

I've lost 12 so far but am expecting to lose the entire difference between my IOC and Clements lists - 43 species - that's a decent foreign trip's worth lost ...

 

[Swindon Addick]

IOC is leaving a lot of coal in people's stockings this year!

Dear Santa IOC please can you deliver a lumping of Scottish Crossbill so I don't have to spend any more time looking for one or trying to convince myself that I've seen one? I promise I have been good. Thank you.

 

[Jeff Hopkins]

Dear Santa IOC please can you deliver a lumping of Scottish Crossbill so I don't have to spend any more time looking for one or trying to convince myself that I've seen one? I promise I have been good. Thank you.

Love it. And in my case, I don't have to be upset that I didn't see one when I went to Scotland!

 

[YuShan]

Love it. And in my case, I don't have to be upset that I didn't see one when I went to Scotland!

I may or may not have seen one. There is no way of knowing really.
The annoying thing is that you can't tick Common Crossbill there either, because it could be a Scottish, so whatever you see it's basically an unidentified bird No tick. . Time to lump it!

 

[Steve Lister]

I may or may not have seen one. There is no way of knowing really.
The annoying thing is that you can't tick Common Crossbill there either, because it could be a Scottish, so whatever you see it's basically an unidentified bird No tick. . Time to lump it!

Or do what a lot of people do - tick three species despite maybe only seeing one. I must admit, I have convinced myself I have seen all three over the years.

 

[bonxie birder]

Or do what a lot of people do - tick three species despite maybe only seeing one. I must admit, I have convinced myself I have seen all three over the years.

Seen such a variation of bill sizes over the years, it’s easy to tick all three

 

[Jeff Hopkins]

Seen such a variation of bill sizes over the years, it’s easy to tick all three

I'm not looking forward to them trying to split the North American Red Crossbill into 10+ species based solely on call notes that can only be distinguished by vocal spectra.

 

[TicoTyler]

I'm not looking forward to them trying to split the North American Red Crossbill into 10+ species based solely on call notes that can only be distinguished by vocal spectra.

Kind of like how Scopoli's and Cory's Shearwaters probably distinguish themselves primarily by smell not sight, although with decent photos they can generally be separated visually for us. But it's going to be an increasing frustration among birders, I suspect, that there are going to be more and more species that for us humans aren't easily distinguished in the field but for the birds themselves they are distinct entities.

 

[pbjosh]

Kind of like how Scopoli's and Cory's Shearwaters probably distinguish themselves primarily by smell not sight, although with decent photos they can generally be separated visually for us. But it's going to be an increasing frustration among birders, I suspect, that there are going to be more and more species that for us humans aren't easily distinguished in the field but for the birds themselves they are distinct entities.

I am not a professional taxonomist but it seems that the general consensus is that Scopoli’s/Cory’s is a much more well defined species pair than anything going on in the mess that is the Crossbills.

Interesting at the moment is Rafael Lima’s proposal to SACC to subdivide Schiffornis into far more species. They would all be tickable by range, presumably, except for overlap areas in the headwaters of river basins. I don’t have any opinion on the validity of the splits but it’s a case of small song differences and purported genetic differences so perhaps more like Cory’s and Scopoli’s in that they are not far diverged but are behaving as good species. If they overlapped with each other (ala the Crossbill call types) it would be madness.

Personally I think the Crossbills are super fascinating but I don’t feel that Scottish or Cassia Crossbill clear the bar to be considered a species, and I’m even dubious of Parrot…

 

[wolfbirder]

I am not a professional taxonomist but it seems that the general consensus is that Scopoli’s/Cory’s is a much more well defined species pair than anything going on in the mess that is the Crossbills.

Interesting at the moment is Rafael Lima’s proposal to SACC to subdivide Schiffornis into far more species. They would all be tickable by range, presumably, except for overlap areas in the headwaters of river basins. I don’t have any opinion on the validity of the splits but it’s a case of small song differences and purported genetic differences so perhaps more like Cory’s and Scopoli’s in that they are not far diverged but are behaving as good species. If they overlapped with each other (ala the Crossbill call types) it would be madness.

Personally I think the Crossbills are super fascinating but I don’t feel that Scottish or Cassia Crossbill clear the bar to be considered a species, and I’m even dubious of Parrot…

lsn't that the fundamental difficulty of over-reliance on DNA? Species may be behaving as individual species but that divergence is only relatively recent.

I don't know enough about it, but I know Crossbill experts who are adamant that there are different species of Crossbill, but exactly where the difference lies and what they actually are is a different matter.

 

[pbjosh]

lsn't that the fundamental difficulty of over-reliance on DNA? Species may be behaving as individual species but that divergence is only relatively recent.

I don’t know if “over reliance” is an issue though I think there are still myriad incomplete analyses and perhaps incorrect conclusions drawn… ultimately it’s just another tool and hopefully is used to complement voice and morphological analyses.

I don't know enough about it, but I know Crossbill experts who are adamant that there are different species of Crossbill, but exactly where the difference lies and what they actually are is a different matter.

Again don’t want to come across as anything of an expert nor say anything too controversial but it seems to me that it’s mostly just the Crossbill experts that are convinced of the species status of the Crossbills. Others, reading their papers, seem to be less convinced.

And to be fair making it just a discussion of species status does take away a bit from how fascinating they are.

 

[YuShan]

Kind of like how Scopoli's and Cory's Shearwaters probably distinguish themselves primarily by smell not sight

The future of birding: birdsniffing
"Sniffed only"

 

[James Lowther]

I think one thing pretty much everyone can agree on is that the current treatment of “red” crossbill species is not correct.

They will either need to be lumped into 1 or at most 2 species, or split into dozens. Particularly in the case of Scottish crossbill I don’t think anyone is convinced that they are uniquely distinct and worthy of species status compared to birds from Vietnam, Luzon, Morocco, Cyprus, Belize etc.

Having said that, I believe that current treatment of the crossbills is identical across the 3 lists that are subject to harmonisation, so it is not surprising that they are being left alone at present. The current round of changes (mostly lumps) to the IOC list are ALL acting to reduce differences between IOC and the other lists, particularly Clements.

So there is seemingly no real prospect of the crossbill issue being tackled until the harmonisation process is complete.

Cheers
James

 

[DMW]

I am not a professional taxonomist but it seems that the general consensus is that Scopoli’s/Cory’s is a much more well defined species pair than anything going on in the mess that is the Crossbills.

Interesting at the moment is Rafael Lima’s proposal to SACC to subdivide Schiffornis into far more species. They would all be tickable by range, presumably, except for overlap areas in the headwaters of river basins. I don’t have any opinion on the validity of the splits but it’s a case of small song differences and purported genetic differences so perhaps more like Cory’s and Scopoli’s in that they are not far diverged but are behaving as good species. If they overlapped with each other (ala the Crossbill call types) it would be madness.

Personally I think the Crossbills are super fascinating but I don’t feel that Scottish or Cassia Crossbill clear the bar to be considered a species, and I’m even dubious of Parrot…

If only there was a taxonomic rank below species level which dealt with weakly-differentiated taxa 😉

 

[Farnboro John]

The future of birding: birdsniffing
"Sniffed only"

Crowds queuing in the dark to inhale the whiff of nesting burrows... awesome.

John

 

[Mysticete]

I am not a professional taxonomist but it seems that the general consensus is that Scopoli’s/Cory’s is a much more well defined species pair than anything going on in the mess that is the Crossbills.

Interesting at the moment is Rafael Lima’s proposal to SACC to subdivide Schiffornis into far more species. They would all be tickable by range, presumably, except for overlap areas in the headwaters of river basins. I don’t have any opinion on the validity of the splits but it’s a case of small song differences and purported genetic differences so perhaps more like Cory’s and Scopoli’s in that they are not far diverged but are behaving as good species. If they overlapped with each other (ala the Crossbill call types) it would be madness.

Personally I think the Crossbills are super fascinating but I don’t feel that Scottish or Cassia Crossbill clear the bar to be considered a species, and I’m even dubious of Parrot…

Pretty much every non-avian taxonomic group has numerous species complexes full of cryptic species that pose id challenged. Bird taxonomy is just catching up!

 

[Farnboro John]

Pretty much every non-avian taxonomic group has numerous species complexes full of cryptic species that pose id challenged. Bird taxonomy is just catching up!

I think for the good of studies other than taxonomic it's time taxonomists were told like Alice: "begin at the beginning, go on to the end and then stop."

I.e. if they are indistinguishable stop looking at them and do something more useful.

John

 

[Kirk Roth]

Kind of like how Scopoli's and Cory's Shearwaters probably distinguish themselves primarily by smell not sight, although with decent photos they can generally be separated visually for us. But it's going to be an increasing frustration among birders, I suspect, that there are going to be more and more species that for us humans aren't easily distinguished in the field but for the birds themselves they are distinct entities.

A modern birding equipment needs to include a UV flashlight, sonogram recorder, aerosol sampling kit, DNA specimen set, your handiest isotopic spectroscope and a magnetometer. Binoculars are optional if you want to be quaint.

 

[Paul Chapman]

Kind of like how Scopoli's and Cory's Shearwaters probably distinguish themselves primarily by smell not sight, although with decent photos they can generally be separated visually for us. But it's going to be an increasing frustration among birders, I suspect, that there are going to be more and more species that for us humans aren't easily distinguished in the field but for the birds themselves they are distinct entities.

In general terms, I think that identifying Cory's & Scopoli's Shearwaters in photos is significantly overestimated. Any time spent looking at the eBird photoset shows that! Misidentified photos seem regular. I posted on one such scenario and did not receive a single response on here and this is not normally a forum where the absence of a credible opinion holds people back. I certainly do not use it as a personal bar.

😀

Post in thread 'Cape Verde Shearwater in Cornwall - Breaking news from RBA (2.03pm 19 Dec)' https://www.birdforum.net/threads/c...ws-from-rba-2-03pm-19-dec.464773/post-4732839

Firstly, you need an angle for the bird which is shown in less than 10% of photos. Even when a bird banks it rarely banks side on and showing the photographer the underside of p10 clearly.

Secondly, you need to get the exposure correct so that you are discerning the patterning in the underside of the primaries properly. Most photos from land in particular show the underside of the primaries overexposed. I have seen a number of these trumpeted as showing Scopoli's patterning. Further any pics of the underside of the primaries are normally overexposed even from boats. I have taken thousands of Cory's pics (mainly I think) in several countries.

My experience is that you can have ten competent photographers photographing a group of say 100 Cory's/Scopoli's with maybe one or two Scopoli's present & one photographer may get a clinching photo whilst everyone else dips. I am up to maybe six pelagics now where that has not been uncommon. Also you can simply end up with inconclusive photos even in the opinion of one of the main authors of the identification paper bobbing around on the same boat. 😀

Of course, in any event, one third of Scopoli's are considered to be indistinguishable on the p10 criteria.

The main identification paper recommends further studies on the one third of cryptic Scopoli's with p10 with less than a 20% white tongue and refers to hybridisation.

So with a camera bobbing around on a boat next to a flock of 100 Cory's/Scopoli's Shearwaters in flight, you need to be setting the identification bar far lower than most bird committees to be identifying more than 10% of the birds in my view. (If they are not flying, you may as well spend your time looking at other birds.)

Most of the simplified comments that I have seen outside of a European context seem to significantly misrepresent the difficulty of the challenge. (A bit like Europeans making comments on Empidonax identification. 😀)

All the best

Paul

 

[Paul Chapman]

Is anyone keeping a tally of which scientists have had the most splits reversed in this process & do they win a prize? 😀

All the best

Paul