The next 10 ABA (North American) splits - 2022 (2 Viewers)

[Mysticete]

Hey folks,

Sometime this spring I am going to be giving a talk on bird taxonomy to my local birding club, and my idea is to sort of do it as a update to Sibley's original list of what he thought the next ten bird splits would be:

The next 10 North American bird splits – Sibley Guides

www.sibleyguides.com

I am going to be going over the science behind splits, and also probably discuss how groups like the AOS work, as well as the ongoing WGAC work. However I then want to highlight some interesting and likely splits. Since Sibley first wrote his blog entry, 4 of these have been split, and the four remaining birds that so far haven't by split by AOS (and thus recognized by the ABA) include Marsh Wren, Yellow-rumped Warbler, Fox Sparrow, Willet, White-breasted Nuthatch, and Spruce Grouse. Of course, since 2010 we have had splits not even in those top ten candidates, while proposals have been submitted and rejected for some of those.

So in assembling a "new" top ten list, what should be on there? Note for the purpose of the list I would like to focus on New World based splits, although I will probably mention very briefly extralimital splits as well (e.g. Great Egret, Merlin, Black Tern, etc) I'd like to gather people's thoughts to assemble a new top ten list.

 

[Jacana]

Steller's Jay
House Wren
Golden-fronted Woodpecker
Whimbrel
Northern Emerald Toucanet
Resplendent Quetzal

 

[gusasp]

I'm placing my bet on, apart from aforementioned on Sibley's list:

• Northern Flicker
• Warbling Vireo
• Steller's Jay
• Mexican Jay
• House Wren
• Swainson's Thrush
• Savannah Sparrow

As for Old World vs New World, I would go for the following candidates (besides Whimbrel):

• Cabot's Tern – closer to Elegant than Sandwich
• American Herring Gull – not at all part of the Herring Gull complex, rather closer to i.e. Glaucous-winged, Glaucous and Slaty-backed Gulls
• Northern Goshawk – Old World population closer to i.e. Black Sparrowhawk than New World
• American Barn Owl

 

[KC Foggin]

I guess this will increase the Bird I D section of the Forum.

 

[Mysticete]

Should also state I am particularly focusing for my talk on species present within USA/Canada, as a large chunk of the crowd does very little international birding. Also delving into the Central America just opens up a much larger number of potential splits that I am less familiar with.

 

[connorco]

My Predictions

• Steller's Jay (supposedly a very good candidate for being split next year based on rumors)
• Warbling Vireo
• House Wren (doesn't really effect NA that much)
• -Fox Sparrow
• - Spruce Grouse
• -Savannah Sparrow
• -Yellow-rumped Warbler
• -Whimbrel
• Herring Gull
• White-crowned Sparrow (Gambelli and leucophyris, pugentensis and nutalli, oriantha)
• Swainson's Thrush
• Dark-eyed Junco (Gray-headed/Red-backed type vs Oregon/Slate-colored/White-winged/Pink-sided, white-winged could be another potential split)

 

[blackburnian2000]

Other possibilities to the ones already mentioned:

• Nashville Warbler/Calaveras Warbler
• Evening Grosbeak (5 call types)
• Canada Jay (Pacific vs Boreal/Rockies)
• Woodhouse's Scrub-Jay (Sumicrast's vs TX Edwards Plateau vs Interior West)
• Bell's Vireo (Eastern vs Western)
• Northern Cardinal (Eastern + Yucatan vs Sonoran vs Sierra Madre del Sur)

Not a split, but I'd be surprised if Common/Hoary Redpoll isn't lumped in the next 10 years.

 

[Mysticete]

Cordilleran and Pacific-Slope Flycatchers are also good candidates for a future lump.

 

[Ian Lewis]

All these predictions are very useful as I'm planning a trip from northern Arizona to Seattle via Yellowstone in June next year and hope to pick up about six life birds.
As many of these potential splits as possible will be added to the wish list for insurance.

 

[Kirk Roth]

Cordilleran and Pacific-Slope Flycatchers are also good candidates for a future lump.

Along with "Island Flycatcher" a good candidate for a future split?

 

[Kirk Roth]

Small owls.

You should not neglect Mountain Pygmy-owl, which is already split by IOC.

I'm told McCall's Screech-owl has attracted the interest of some people in Texas. If some original research gets done, most people seem certain from anecdote that a split is warranted. Probably not a great choice for speaking about, given that the lack of studies is what has kept this off of most people's radar - but there is also a feasible chance of a split in the next decade if some (relatively easy) studies are done.

Haida Gwai Owl is every bit as much of a species as McKay's Bunting, for what that's worth.

And also, Common Teal - just saying.

 

[Mysticete]

For what it's worth, my own two cents would, in no particular order, list these as the next most likely

Yellow-rumped Warbler
Fox Sparrow
Spruce Grouse
Savannah Sparrow
Steller's Jay
Canada Jay
Warbling Vireo
Great Blue Heron
Black Noddy
Willet

The first four are already split either by IOC or Birdlife (or both), and the WGAC will have to vote on them. and if the vote is positive I could see either AOS reconsidering their decision or ABA needing to make some decisions on authorities to follow, given the importance of ebird.

The Jays, Vireo, and Noddy (which would involve a split of the Hawaiian population vs others) all have recent papers supporting splits that are pretty good, and I have heard rumors of Steller's possibly being voted on by the NACC as early as the next proposal round. There is also a new paper directly rebutting criticism of the Great Blue/Great White Heron split.

Willet just seems obvious, and hopefully there are more papers in the pipeline, since the last attempt I think was a narrow failure.

 

[lgonz1008]

Difficult to predict the logic behind splits at times, but I'd say these are good enough candidates within continental US:

• Willet (Eastern and Western)
• Yellow-rumped Warbler (Myrtle and Audubon's)
• Great Blue Heron (Great White and Great Blue)
• Dark-eyed Junco (Gray-headed and the rest)
• Yellow Warbler (Northern, Golden and Mangrove) this one is less likely but feels overdue at this point

A bit more international, but with good representation in the US and Mexico:

• Northern Cardinal (Northern and Yucatan)
• House Wren (Northern, Southern, Cozumel and every Lesser Antilles island)
• Carolina Wren (Northern and White-browed)
• Golden-fronted Woodpecker (Golden-fronted and Velasquez)

 

[Mysticete]

I am trying to make a database of splits (extralimital and within the region) that might effect the ABA area, alongside the evidence/papers/etc that support them. It's slow-going, as it takes a bit of time for me to go through the literature for the splits. The last column FYI is just my initial thoughts on the probability of a split

So far, I have finished up Anatidae...I would welcome any comments, specifically comments on papers/evidence I have missed.

ABA split table.xlsx

Shared with Dropbox

www.dropbox.com

 

[raymie]

Wasn't there talk of splitting the southwestern Northern Cardinal population at one point?

I had no idea Gray-headed Junco was possibly on the docket to be split. Is it really that different from the others? It looks just like Red-backed!

 

[Björn Bergenholtz]

Maybe (?) the Hudsonian Dunlin Calidris (alpina) hudsonia TODD 1953, at least it was discussed here on BirdForum, back in 2010 (see here, with references). OD here, as "Erolia alpina hudsonia". Also listed here.

If it's still in consideration, or not, is unknown to me.

 

[Mysticete]

Wasn't there talk of splitting the southwestern Northern Cardinal population at one point?

I had no idea Gray-headed Junco was possibly on the docket to be split. Is it really that different from the others? It looks just like Red-backed!

Yes, there was a NACC proposal sometime back which failed. IIRC, the most divergent population is the Long-crested form that I think occurs down in Mexico (Yucatan? Again less familiar with this region), so the most likely split is extralimital to the region.

Dark-eyed Juncos are...complicated. I think part of issue is that Red-backed Juncos are at least sometimes found to be more closely related to Yellow-eyed Juncos (which are also a mess).

 

[abirdingguy]

I am trying to make a database of splits (extralimital and within the region) that might effect the ABA area, alongside the evidence/papers/etc that support them. It's slow-going, as it takes a bit of time for me to go through the literature for the splits. The last column FYI is just my initial thoughts on the probability of a split

So far, I have finished up Anatidae...I would welcome any comments, specifically comments on papers/evidence I have missed.

ABA split table.xlsx

Shared with Dropbox

www.dropbox.com

The ABA published such a table for intra-region splits and lumps in 2016 (although with fewer columns). It can be viewed at To Be a Species or Not To Be a Species?. After the references in the article, there is also a less-detailed, second list covering potential splits and lumps where only one effected taxon is in the ABA area.

I've hoped to see an updated version of the table. Thanks for undertaking this.

By the way, one potential split in the article that has puzzled me for years now is the Olive-sided Flycatcher. I hadn't seen it mentioned elsewhere, and the listed reference is clearly erroneous.

 

[Mysticete]

The ABA published such a table for intra-region splits and lumps in 2016 (although with fewer columns). It can be viewed at To Be a Species or Not To Be a Species?. After the references in the article, there is also a less-detailed, second list covering potential splits and lumps where only one effected taxon is in the ABA area.

I've hoped to see an updated version of the table. Thanks for undertaking this.

By the way, one potential split in the article that has puzzled me for years now is the Olive-sided Flycatcher. I hadn't seen it mentioned elsewhere, and the listed reference is clearly erroneous.

I've tried to find additional references for this as well, and have largely come up empty, especially as there doesn't appear to be much vocal differentiation?

Another one I have heard mentioned, I think by David Sibley in a blog post? Was Golden-crowned Kinglet. Which biogeographically would make sense, but I haven't seen much work suggesting this.

 

[blackburnian2000]

Was thinking about this some more today and reading through recent papers. Further split candidates:

White-crowned Sparrow (nuttalli/pugetensis vs leucophrys/gambelli/oriantha)
Greater White-fronted Goose (Tule vs Greenland vs everything else)
Brown Creeper (North America vs Mexico/SE Arizona)
Bushtit (Pacific coast vs Interior West/Mexico)