Friendly game with 2021 AOS prosposals

We usually talk about the taxonomic changes the AOS accepts for bird taxonomy in terms of implementing it into iNat but I suggest something different this time around. Let’s have fun and have a thoughtful discussion on what we think the committee should do. Proposal sets A through C have been published and I don’t think any more will come, most years only have three sets of proposals with the except of 2019. Anyway, you can view the proposals here. I am only going to vote on species that will directly affect me but you can do whatever you like.

2021-A-3: Split Mew Gull Larus canus brachyrhynchus and rename as Short-billed Gull
Yes… and no. As a person who readily sees Mew Gull in the winter, I think they’re distinct enough that if a vagrant Common Gull were to show up in my neck of the woods, I could identify it fairly easily. I’ve always found the Common Gull to be the European equivalent to the Ring-billed Gull. However, I don’t agree on a name change. I’ve known about the name Short-billed Gull being applied to this subspecies but I’ve never called it that, no any other birders I know. Though I’ve never been to East Coast, don’t they call the European vagrants Common Gull? So personally, I think retaining the name Mew Gull is better.

2021-A-4: Revise generic limits in the Phalacrocoracidae (cormorants)
No. I have seen Double-crested (suggested to be placed in new genus Nannopterum), Pelagic and Brandt’s Cormorants (new genus Urile) and all I can say is, if you’re armed with only binoculars, it’s going to hard to identify cormorants in coastal bays. Maybe I’m basing my opinion too much on morphology but all the US species of cormorants look very much alike and only good views can acquire species identification and I can’t see how a generic split will solve issues, especially since the most controversial taxonomic debates are fueled by phylogenetic studies.

2021-A-6: Change the linear sequence of the gnatcatchers (Polioptila spp.)
Yes. Why not? The proposed sequence organizes Polioptila not only from blackest to black-capped to gray-headed but also geographically, since closely related species usually diverge with a common ancestor so adjacent species are going to be more closely related then those they have no contact with.

2021-A-9: Resurrect Corthylio for Ruby-crowned Kinglet
No. The external differences between the Ruby-crowned Kinglet and other regulids are so subtle and insignificant to identification, that such features only apply to banders. Resurrecting Corthylio seems redundant to my eyes and if any change is a must, maybe a linear sequence change.

2021-A-10: Change the linear sequence of species in Chaetura
Yes. Like with the gnatcatchers, I see no reason not to go forward with this change as it better represents the relationships between morphologically similar species with the support of phylogenetic analysis.

2021-A-13: Treat McKay’s Bunting Plectrophenax hyperboreus as conspecific with Snow Bunting P. nivalis
Yes. We have established for many years what the ranges and identification marks for these two populations are but yet we keep bending the rules. I suggest one of two problems occur. One, that identifiers push the limits of McKay’s variation, or two, the McKay’s Bunting is just a whiter variation of the Snow Bunting, not only that but a clinal variation. The US West Coast has five records of McKay’s, even though that’s well over a thousand miles from it’s “winter range”. That’s not a lot but why would a juvenile bird split off from its flock and join a Snow Bunting flock if they are different species? Maybe I’m comparing apples to oranges but those are my thoughts.

2021-B-7: Revise the linear sequence of passerine families
No. I agree with some aspects of the new linear sequence, such as shrikes being more closely related to corvids than vireos to corvids, but overall, it’s not something I can get onboard with it. For example, Yellow-breasted Chat, Cuban warblers, then blackbirds? Sorry, that’s a deal breaker since we found a Yellow-breasted Chat x oriole hybrid, and that alone should make taxonomists reconsider family limits.

2021-B-10: Treat Andean Duck Oxyura ferruginea as conspecific with Ruddy Duck O. jamaicensis
Yes. The SACC has already accepted this mostly South American issue and we should be aiming for consistency.

2021-C-8: Treat Cinereous Owl Strix sartorii as a separate species from Barred Owl S. varia
Yes. Though the morphological differences are not as distinct as Spotted vs Barred, I have several reasons to believe the Cinereous Owl needs to be split. Owls are nonmigratory and tend to diverge more quickly and easily than other species of birds. Because of their tendency to never range far from the place they hatched, this means gene flow is almost nonexistent with adjacent populations. In this case, a distinctly different call and genetic differences are definitely suggestive of speciation. So I’m an all for owl splits like this and I hope someday we will see the Haida Gwaii Saw-whet Owl, Boreal Owl split, Barn Owl split, Great Gray Owl split, etc.

2021-C-11: Transfer Spruce Grouse Falcipennis canadensis to Canachites
No. Though it seems the evolutionary history of the Spruce/Siberian Grouse goes way back, they are still each other’s closest relatives and I would think for consistency’s sake, if we were to follow through with this change, the generic limits of Tetrao needs to be revised as well with having so much more time to diverge.

2021-C-19: Treat Catharus swainsoni as a separate species from C. ustulatus
No. Just simply no, no room for debate. The problem with clades like these is the fact that interior western individuals look remarkably like Alaskan coastal individuals. For example, I saw a Hermit Thrush last September that was very photo cooperative. I had field identified it as a guttatus subspecies because it looked like it was from the Pacific group but not quite like one I’d see on the western side of the state. It turned out that it was subspecies from the Nevada island ranges that migrated north, or in other words, the expected group. This phenomena occurs in other species like the Slate-colored Fox Sparrow and unalaschensis Sooty Fox, in which they are very similar in plumage despite breeding thousands of miles away from each other. I feel this same occurrence is happening with the Swainson’s Thrush and I would discourage any taxonomic action.


I and everyone I saw discussing it, agree that there’s no need to rename Mew gull, it should be a name for American species/subspecies, now AOS have weird name system for L. canus and they want to make it even worse.
What does Revise the linear sequence of passerine families mean, could you explain?

Change the order the families would appear in on a list sorted by taxonomy (ex. ABA checklist, an eBird checklist, ect.)

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That sums it up really well. I will say that linear sequence is based upon phylogenetics or how closely related one family is to another. The reason why it’s been changing drastically the last decade or so is because 20th century taxonomy was mostly based on best guesses. Now we have the genetics to confirm or deny these guesses. ’

This is the purposed sequence though I’ve edited it some as I tried to merge the current sequence with it. So from up to down, left to right, that’s the suggested order of the families. Each color coated section means no change, and numbered according to their current status. So for example, nuthatches/creepers (15), wrens (16), gnatcatchers (17) is the current sequence but the new sequence suggests gnatcatchers come before wrens so they’re color coated differently. Or the three families of Old World warblers (24) is proposed to be between larks (10) and swallows (11), rather than various other Old World families. Hopefully that’s not too confusing.

Screenshot 2021-04-09 210123

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