AOU Committee on Classification and Nomenclature (North & Middle America)

Comments on Proposals 2017-A

2017-A-1: Split White-faced Ground-Sparrow Melozone cabanisi from Prevost's Ground-Sparrow Melozone biarcuata
2017-A-2: Revise the generic classification of the subfamily Anserinae
2017-A-3: Transfer Blue-gray Noddy Procelsterna cerulea to the genus Anous
2017-A-4: Split North American Red Crossbill Loxia curvirostra into two species
2017-A-5: Transfer Wilson’s Phalarope Phalaropus tricolor to a monotypic genus, Steganopus Vieillot 1818
2017-A-6: Change the English name of the Ring-necked Duck Aythya collaris
2017-A-7a: Transfer Intermediate Egret Mesophoyx intermedia to Ardea
2017-A-7b: Transfer Cattle Egret Bubulcus ibis to Ardea
2017-A-8: Revisit the proposed split of Circus cyaneus and Circus hudsonius
2017-A-9: Split Yellow-rumped Warbler Setophaga coronata into three species
2017-A-10: Split Willet Tringa semipalmata into two species
2017-A-11a: Modify our treatment of juncos: Recognize bairdi as a species
2017-A-11b: Modify our treatment of juncos: Recognize alticola as a species
2017-A-11c: Modify our treatment of juncos: Lump phaeonotus and hyemalis
2017-A-12: Change the linear sequence of species in the Scolopacidae

Split White-faced Ground-Sparrow Melozone cabanisi from Prevost's Ground-Sparrow Melozone biarcuata
Also see proposal 2017-C-6 for English names

YES - 2 without comment.

YES. These differ in color, vocalizations, morphology; allopatric distribution. As pointed out, the color differences are similar to that seen in other recognized species. In my opinion, there are more data arguing for separate species status at this point than continuing to maintain all three in one species.

YES. I am curious about the pattern of genetic differentiation among these forms, but the phenotypic evidence is sufficient by itself.

YES. There are a number of weaknesses in this proposal that made me question whether cabanisi is not just a more differentiated subspecies. For example, allopatric distribution is not a particularly useful criterion for species limits. Nor is it mentioned that this is an oscine passerine, in which song learning commonly produces geographic variation. Finally, we expect morphometric and plumage differences among allopatric populations of subspecies – how are these sufficient to merit species status? Only going back to the original paper do I find enough information to convince me to vote YES on this proposal: the sonograms and photo of the specimens (Table 1 in the proposal is not useful in this context for determining species limits) were tantalizing enough to read the original in more detail. Coupled with the careful documentation of vocal differences (in conserved characteristics) and plumage differences is the observation that they are on a par with other full species in the Emberizidae. ABSTAIN on the English names.

YES. I am most convinced by the vocal differences, which are congruent with differences in plumage and morphology. It would be nice to see the results of playback experiments, but I think it makes sense to split these based on the available data. I agree that having three species in the genus with 'white' in the name, pertaining to different head regions, is confusing. For that reason, I prefer Prevost's and Cabanis' although I see the conflict with our guidelines (in keeping Prevost's for one taxon) and am open to other ideas. If we were to use 'white-faced' then it would better apply to biarcuata and not cabanisi.

YES. these are clearly two strongly differentiated, broadly allopatric taxa, with marked vocal differences. As for common names, "White-faced" clearly describes cabanisi much better than biarcuata, which only has a little white on the face. Since White-faced has been widely used for the combined species, why not use Cabanis' Ground-Sparrow for M. cabanisi, along with Prevost's for M. biarcuata?

YES. It is rather surprising that cabanisi and biarcuata were ever lumped in the first place, given their quite dissimilar plumage pattern and their geographical separation. The morphometrics and, to a lesser extent, vocalizations also differ, reinforcing species status. The differences are on par with differences between the congeners M. fusca and M. crissalis, or species within Peuacea. Re: English names - without other input, I choose Prevost's (for biarcuata) and Cabanis's (for cabanisi) Ground-Sparrows. Cabanisi has a small peripheral range in comparison to biarcuata.

YES. The vocal differences in both songs and calls are sufficient evidence, in my opinion for a return to Ridgway’s classification as two species, which should never have been changed in the first place. Use of vocal differences in allotaxa of oscines has its obvious problems, but empirically, parapatric oscine species always show vocal differences, so they provide a reliable index to species rank under BSC. The plumage differences are, as Sandoval pointed out, roughly equivalent to those among taxa we now treat in Buarremon as separate species. The morphological differences are interesting and valuable data in terms of describing geographic variation, but generally useless in determining taxon rank in allotaxa. But in both voice and plumage, these allopatric taxa have diverged to a degree roughly equivalent to parapatric tropical emberizid taxa between which there is no free gene flow and between allopatric taxa treated as species. Playback trials are needed to confirm all this, but the current data suggest a return to Ridgway is the best solution. Note that this paper invalidates hartwegi as subspecies, so this needs to be tracked for the eventual subspecies volume.

The English names are a problem. Prevost's is the current name for the parent species as well as the proposed name for the daughter species. However, the two names in Ridgway were Prevost's and White-eared, and so when the two were lumped, a new name should have been concocted for the broadly defined species, so that’s where the mistake was made. This one is sufficiently complex that I think it's worth a separate proposal to outline the issues, especially if we are not in a rush. As long as we have to make a change, I recommend getting it right the first time, with the rationale outlined.

YES. Actually it is rather amazing that they were not split long before. The morphological differences alone would lead one to that conclusion, let alone the well separated ranges between the two northern subspecies and the Costa Rican birds. The vocalizations, as described, sound different too, although Xeno-Canto has only northern birds (none of cabanisi). The recognition of hartwegi from the Mexican part of the range (Chiapas) seems dubious. Byers et al. 1995 says it is similar to biarcuata but the upperparts are more grayish-olive.  Monroe (1968) said "I cannot distinguish the supposed Chiapan race, M. b. hartwegi; I therefore considered the species monotypic." Not sure how he regarded Costan Rican cabanisi. There is not much of a geographical barrier, if any, between hartwegi and nominate biarcuata.

About the question of English names, I'm somewhat baffled by those suggested by the author of the motion. The nominate northern subspecies group (Chiapas to Honduras) is the one with a white face, the one that Prevost and Des Murs actually described in 1846, so why name the Costa Rican bird White-faced Ground-Sparrow when the face, especially the auricular, is not dark? From my own viewpoint, I like patronyms so would prefer to use Prevost's as the English name for the northern species, and counter with another patronym for cabanisi, Cabanis' Ground-Sparrow. Cabanis lost out with his tanager (Tanagra cabanisi), I suppose a victim of Eisenmann's purging of established (patronyms) English names for Middle American species a half century or so ago.  But, if there is avoidance of patronyms, I would use White-faced Ground-Sparrow for the northern birds and White-spectacled, or White-lored for the Costa Rican birds.

Byers, C., U. Olssson, and J. Curson. 1995. Buntings and Sparrows, a Guide to the Buntings and North American Sparrows. Pica Press.
Monroe, B.L., Jr. 1968. A Distributional Survey of the Birds of Honduras. Ornithological Monographs, No. 7. American Ornithologists’ Union.


Revise the generic classification of the subfamily Anserinae

YES - 2 without comment.

YES. The results are solid that maintaining Chen renders Anser polyphyletic. Bar-Headed Goose does have a name available Eulabeia Reichenbach 1852.  But 4.5 mya does not seem that old a split. For instance, the paper dates the bernicla vs. other Branta split as much older (6.7 mya). Re: retaining Chen but transferring indicus, I think a broad Anser is fine, given their morphological similarity.

YES. Given the data, the only other solution would be to put Bar-headed Goose in its own genus and preserve Chen. I do not know goose morphology (and don’t have access to specimens) well enough to know whether that is reasonable. Ottenburghs et al. 2016 did not address this. Livezy (1996) found morphological support for a monophyletic clade of Chen + indicus, but treated them all as Anser; and the molecular support for Chen is not particularly strong (Ottenburghs et al. 2016: 310). So let’s call Anser the answer.

YES. However, contrary to the proposal, I like the alternative of retaining Chen and transferring indicus to Eulabeia.

YES. I agree with some of the comments that have already come in, which correctly point out that other treatments are certainly possible. But any of those alternatives would end up recognizing monotypic genera that, under this treatment, are appropriately lumped into a larger genus (I think). There is no fundamentally right or wrong choice in this kind of situation, but given the pattern of divergence in the time-tree, I think that the lumping approach provides the better guide to relationships in this group.

YES. This seems like the simplest solution. Otherwise, Bar-headed Goose would need its own genus.

YES. The new results require that either Chen be merged into Anser or indicus be treated in a separate genus. It actually looks to me, strictly from the branching pattern in the tree, that the latter is perhaps a better solution, but this is a subjective decision that would require a separate proposal in my opinion. Although the three clusters of geese within broad Anser are discrete groups in terms of plumage, all of them are basically built out of the same morphological mold. If there is a time-calibrated tree that would allow rough approximations of lineage age, I could be convinced, but this one is an uphill battle for me. Unless someone wants to make a case for this, for now I go with broad Anser (type species anser). Chen is already merged into Anser in Dickinson & Remsen (2013), prior to Ottenburghs et al. (2016).

YES. I'll go with majority consensus on this one, although I would prefer to recognize other existing genera for the older lineages. The tree suggests an alternative treatment not mentioned in the proposal: that, given their evident Miocene origin, the brants vs. other Branta should be generically separate (with the brants in Bernicla Stephens, 1824), and that the Bar-headed Goose Anser indicus should revert to its old genus of Eulabeia Reichenbach, 1852 (of which it is the type species). If this is done, then it is a judgement call whether Chen should be lumped with Anser. Since the proposal doesn’t present this alternative it is unlikely the committee would go this route, but it seems we should at least consider that this alternative exists before lumping Chen. The tree also suggests that the specific status of Black Brant will need reevaluation in a future proposal.

NO. It seems like this is a case where recognizing indica as a separate genus and maintaining the well-defined and morphologically pretty tight general of Anser (very strict sense) and Chen. I think that the problem here is that the possibility of a 3 way split is not considered in the proposal and should be. Our options are only the status quo, which seems clearly wrong, and a lump, which I think obscures useful information. I vote this way despite not knowing there is an available name for indica.


Transfer Blue-gray Noddy Procelsterna cerulea to the genus Anous

YES - 4 without comment.

YES. It would be nice if the nuclear locus supported the phylogeny, but the mtDNA signal is strong and the morphology is so similar that I prefer this solution.

YES. This seems uncontroversial.

YES. It appears that the pale noddies were split from the darker noddies solely on their pale plumage. It is therefore not surprising that they fall within the darker noddies, which are structurally more diverse.

YES. Merging them into one genus seems like the simplest solution. I prefer that to resurrecting Megalopterus for the Lesser and Black Noddies.

YES. This seems straightforward based on phylogenetic data.

YES. An easy decision, one required by the phylogenetic results. The chances of this being just an mtDNA gene tree artifact are very small and the alternative of resurrecting Megalopterus doesn't make sense from morphology.


Split North American Red Crossbill Loxia curvirostra into two species

YES. There is now strong and complementary behavioral, experimental, ecological, phenotypic, and genetic evidence that the South Hills crossbills are functionally a separate species under the BSC. The earlier concerns about type specimens have been addressed. It is certainly the case that the 'red' crossbill group is a messy one in terms of where to draw the lines among species (and even messier in the field, especially when the birds are not vocalizing) and that it will likely require additional taxonomic attention as new information comes in on some of the other forms. However, given the accumulated weight of the evidence for the realized distinctiveness of the South Hills population, I think that we would be very remiss not to assign it species status at this point.

YES. Lots of new data and analyses, including genomic level data now support species-level status.

YES. Data are now overwhelming, in my opinion, for recognition of sinesciuris (love that name) as a species (although it might be appropriate to wait for formal appearance of Parchman et al. 2016). Problems with the original evidence have now been addressed. Some might argue that we should wait until Red Crossbill is dismembered completely, but who knows when that will happen, given the still unsolved problems of identification of the type specimens. As for English name, I like Cassia Crossbill over South Hills Crossbill for the reasons outlined in the proposal.

YES. I am sympathetic to the idea that we should wait for somebody to figure out the whole complex before making this split, since this is only one of several species that will eventually need to be split out of Red Crossbill. But the data here look really strong, and it doesn’t seem like there is any immediate likelihood of the whole complex being addressed for a variety of reasons. It doesn’t seem like recognizing this now impinges in any way on what we might do in the future, so I think this makes sense.

YES. The larger genomic dataset, the larger sample sizes, and the occurrence of sympatry between call types 9 and 2 all suggest that this is a biological species.

YES. I voted yes on splitting these with the 2009 proposal, but now the evidence is better, even, overwhelming that sinesciuris is genetically and morphologically separate from other Red Crossbills, even in the face of huge opportunities for gene flow from these other taxa. I think the evidence presented in the paper and proposal dispel any notions that the differences may not be genetically base or that the specimens have not been adequately vouchered. I am not wild about the English Names given (South Hills and Cassia). Cassia is a well-known ornamental tree, and a very obscure county. Why not call it Lodgepole Crossbill?  It may not be the only crossbill to use lodgepoles, but its coevolution with this tree is driving its speciation. Or Squirelless Crossbill.

YES. I am glad to see this proposal, and agree that a split is warranted by the combination of genomic, vocal, and behavioral (low frequency of hybridization) data. I'm not crazy about either name ("Cassia" or "South Hills"), but I will go with "Cassia" for the reasons given. Also, if you google "South Hills" you get results from southern California, including "South Hills High School" in West Covina and "South Hills" in the Transverse Ranges: (

YES. Very strong evidence on multiple fronts has now been presented showing that hybridization is rare between L. sinesciuris and all other forms, despite frequent sympatry. The analysis also shows that this is not the case for the other sampled NA forms north of Mexico, which suggests that recognition of sinesciuris as a full species is unlikely to mean that we'll ultimately need to recognize numerous other crossbill species. As to a common name, I and I'm sure many others associate "Cassia" with a spice or herb, but "South Hills" is even less helpful. I suppose Cassia is as good a name for a crossbill as Gunnison is for a sage-grouse, so I’ll support that.

NO. Wait on Crossbills.

NO. This is strictly a philosophical vote and I realize that my vote is a protest vote. I don't doubt that under any species definition, Loxia sinesciuris is best treated as a separate species. My issue is that this along with previous taxonomic splits within this complex are mere pin pricks in terms of sorting out this very complex topic. I continue to prefer an overall taxonomic overview with specific recommendations based on the distinct vocal types. Yes, huge problems in matching the call note types to the currently assigned subspecies and designating types, etc. Let's see in Loxia curvirostra we have some 19 ssp. recognized in the latest edition of Howard & Moore (Dickinson and Christidis 2014), some eleven in the Old World and eight in the New World.

In the Old World the Parrot Crossbill (Loxia pytyopsittacus) and the Scottish Crossbill (Loxia scotica) have been split. Turning to my trusty Svensson (2nd edition, 2009) there is a nice painting of Parrot Crossbill and it does indeed look deep billed and for the call I see the transcription: "Call very like Common Crossbill's (=Red Crossbill), but on average deeper and harder, more echoing, often less 'clipping' (cf. "Common Crossbill") and with harder initial consonany, 'tupp-tupp-tupp-….' Difference can be detected by the trained ear, and is easiest way (outside Britain) to identify the species despite some individual variation in voice." For Scottish Crossbill we get the encouraging art annotation: "all measurements intermediate between Parrot and Common." Under the description we get in part: "Within the species range in Scotland, Parrot Crossbill, probably not safely distinguishable in the field." And under voice: "Call intermediate between those of Common Crossbill and Parrot Crossbill. If Parrot and Common have calls that are "very like" one another, then Scottish and Common by implication must have calls that are extremely similar to one another. If one looks at the ranges of other Old World ssp. we have endemic subspecies on the Baleric Islands (balerica) from the mountains of south-central Vietnam (meridionalis) and on Luzon in the Philippines (luzoniensis). Does anyone really believe that with the split of Scottish and Parrot we are on the right track in deducing the complexities of this species in the Old World? Perhaps it might have something to do that the great percentage of ornithologists (and birders) in the Old World are in northwestern Europe and probably most of the other taxa are unstudied, especially in a detailed analysis and comparison of their vocalizations.

In the New World, we have split Hispaniola Crossbill (Loxia megaplaga). That taxon was until the last decade considered a ssp. of White-winged Crossbill. My memory from the proposal back then was that this bird was actually more closely related to Red Crossbill, one with narrow wingbars, so a change was necessary. Yet, I see from Howard & Moore (Dickinson and Christidis, 2014), the linear sequence is: L. pytyopsittacus (Parrot Crossbill), L. scotica (Scottish Crossbill), L. curvirostra (Red Crossbill), L. leucoptera (White-winged Crossbill), and L. megaplaga (Hispaniola Crossbill), thus Hispaniola Crossbill is more related to White-winged than Red.

Now we have the elevation of sinesciuris to species status. OK, it's isolated with little hybridization and the calls are distinctive (didn't find them on my quick check of Xeno-canto, but there were many dozens of entries, most of which were from the Old World). My central question: surely there are others that are equally, if not more, distinctive? In particular I was struck by the small, small billed birds (minor?) that invaded the lowlands of CA last winter, birds that had much higher pitched calls. They certainly sounded different from the ones I hear in the Sierra and that means something with my gradually failing ears. And they were closely tied to firs with small cones while the Sierra birds are closely tied to the big cones of yellow pines (mainly Jeffery Pines). I see that Benkman is suggesting that the Mexican Red Crossbill (stricklandi) is also possibly (likely?) separate. It just seems like a larger Red Crossbill with deeper calls. But what about those small birds that feed on fir cones and give high pitched calls? And how does the ssp. rea Phillips 1981 listed in Howard & Moore (Dickinson and Christidis 2014) fit in? Its range is listed as Idaho, but where in Idaho? Howard & Moore (Dickinson and Christidis 2014) don’t list sinesciuris as a valid ssp., even though they have a footnote for it (NACC’s failure to split it earlier).

I realize that the entire subject of Red Crossbill is a minefield of taxonomic difficulties and I will be the first to admit that I'm not a crossbillite. I welcome everything that has been contributed and to me it is one of the more exciting contributions to modern field ornithology in recent decades. I love it, even if I don’t understand it! In the past with difficult combination groups like Solitary Vireos I have sort of felt that we were more than 50% of the way through the complexities before there were specific motions made for taxonomic changes. Here, I doubt we are even 10% of the way. The family Fringillidae seems fraught with taxonomic complexities as we have experienced with redpolls. Vocalizations are surely important in revealing clues as many have suggested. Some species like Purple Finch, Pine Grosbeak (vocalization studies of modular calls were published by Adkisson decades ago), and Evening Grosbeak, all of which give geographical based distinctive calls.

One thing that does surprise me, if one is looking for low hanging fruit in this family just turn to Loxia leucoptera. The Old World ssp. (bifasciata) and New World (nominate leucoptera) give distinctively different calls to my ears (lots of samples on Xeno-canto from both New and Old World). They have different bill structures and different plumage too. Here we have only two. Seems like a simple split from my perspective. Oh well.

Oh, English names. Calling this the "South Hills Crossbill" seems to give it more importance than I’m comfortable. For that and for the reason Benkman points out that this taxon is found in two mountain ranges (South Hills and Albion Mountains), I think Cassia Crossbill is more accurate. These two ranges are found in Cassia County, Idaho. So, if the split goes through which is extremely likely, I vote for Cassia Crossbill for the English name.

Dickinson, E.C. & L. Christidis (Eds.). 2014.  The Howard & Moore Complete Checklist of the Birds of the World. 4th Edition, Vol. 2, Aves Press. 
Swensson, L., K. Mullarney, and D. Zetterstrom. 2011.  Birds of Europe. 2nd Edition.  Princeton University Press.


Transfer Wilson’s Phalarope Phalaropus tricolor to a monotypic genus, Steganopus Vieillot 1818

YES - 1 without comment.

YES (Option A). I strongly support this. Red Phalarope P. fulicarius and Red-necked Phalarope P. lobatus are obviously rather closely related. Their behavior, basic plumage, and even their vocalizations are all similar, the call of Red being higher pitched and sharper. But Wilson’s is something entirely different. For starters their calls are a deep low grunt, unlike any other wader I know of. I suppose the closest comparison might be to the genus Plegadis (dark ibis). Secondly, yeah they swim like the other phalaropes, but so do avocets. Wilson's spends a great deal of time on the shore, especially the juveniles, and their walking gait is utterly unique. They sort of lurch forward and have this almost slow, reptilian movement, very peculiar. I enjoyed the discussion in the motion about what is a genus. Well to quote Potter Stewart on a different subject…."I know it when I see it." This species belongs in a different genus from the other two phalarope species. It certainly seems to belong in its own genus more than such other species as McCown's Longspur (Rhynchophanes mccownii) or perhaps even Terek Sandpiper (Xenus cinereus) which seems pretty Tringa like, its call sounding like Wandering Tattler (Tringa incana). I wish that in addition to molecular support, vocalizations and behavior could also be factored in when deciding genus recognition. Oh, Red Phalarope and Red-necked winter primarily at sea, while Wilson’s winters on ponds and lakes, chiefly on the Argentinian pampas but also on high elevation  Andean lakes.

YES (Option A). The split is deeper than is usual within shorebird genera, commensurate with its distinctive morphology and ecology.

YES (Option A). Wilson's Phalarope is clearly the outlier in morphology (as quantified by Livezey) and behavior (e.g., facultative highly cursorial foraging behavior, as in many Tringa) with respect to the other two phalaropes, and this is consistent with the branching pattern in the tree, which suggests that the separation of tricolor from the ancestor of lobatus+fulicarius represents an old split, deeper in the tree than the node that unites all of now-broadly-defined Tringa. I don’t think it is fully appreciated how different tricolor is from the other two species called phalaropes. I think there are more similarities between Bartamia and Numenius than there are between tricolor and the other two phalaropes; Bartramia is basically a short-billed curlew that we maintain in a monotypic genus based on bill shape (IMO). As for the dislike of monotypic genera by some, I continue to point out that the monotypy of a monotypic genus is at the mercy of re-ranking of subspecies within the species as separate species, or discovery of extinct, fossil congeners. Why should either of these potential results affect the taxon ranking at the genus level? Further, placing a taxon in a monotypic genus does convey phylogenetic information, namely that the taxon has no close relatives in the tree. Placing each species in its own genus (Option B) is the worst of the three and, in my opinion, unacceptable. It makes no sense with respect to comparative branching patterns in the Gibson-Baker tree unless we split Tringa into 5 genera and Actitis into 2 genera.

NO (Option C). I don't see any strong argument for making this split.

NO (Option C). For the sake of stability, I don't think we should change genus-level classifications unless there is a change in topology that requires a change. I don’t think I see anything in the proposal to indicate this. Furthermore, as pointed out in the proposal, maintaining them in one genus is consistent with the topology and branch length (basically an unresolved polytomy of 4 genera). Although Wilson's differs from the other two, I think it would be tough to argue that it differs from the other phalaropes to the degree that phalaropes differ from Tringa, Actitis, and Xenus.

NO (Option C). The three Phalaropus form a relatively shallow monophyletic group and share many traits.

NO (Option C). If all three are monophyletic, I do not see reason to split them up, given their similarities. I realize that Wilson's is an outlier in some respects, but it is clearly a Phalarope in my eyes.

NO (Option C). Given that these are a monophyletic group and have some distinctive morphological and behavioral adaptations that standout from other sandpipers, I think we are best served by the status quo.

NO (Option C). Phalaropus does seem to be an equivalent genus-level clade in comparison with Tringa, Actitis, and Xenus. It might be noted that Livezy (2010) also recognized several other monotypic shorebird genera that we do not recognize, e.g., Aphriza, Tryngites, Philomachus, Limicola, Micropalma. Selection seems to be causing some degrees of divergence not so evident in the genetic data, and maintaining a Phalaropus as a three-species genus would fit with these other changes we’ve made to monotypic genera in the family. However, I am comfortable with a subgenus Steganopus. There are several other potential monotypic generic revisions to make and I don't like going at it piecemeal using very different datasets.


Change the English name of the Ring-necked Duck Aythya collaris

NO - 1 without comment.

NO. If we start changing long-established English names to make them more amenable to learning field marks for new birders, where does it end? This name has been in use literally "forever" ornithologically as well as in waterfowl management, and as far as I can tell, new birders have managed to overcome the obstacle of not having a name that points out the species' most conspicuous feature. If this were, say, 1880, then yes it would be a good idea to change the name to something more field-markish. However, the name is also accurate – the bird does have a ring around its neck (ergo collaris) that can indeed be seen under the right light. In fact, trying to see the chestnut ring would be a good way to get novices to look at the species more carefully. I also remind everyone that bird-watchers aren't the only ones who use English names; bird-banders, taxidermists, hunters, artists, etc., also use them, and these people see the birds in the hand, when the chestnut neck ring is clearly visible.

Concerning the "Ring-billed Duck" proposal and any such proposals we get in the future, the AOU CLC long ago established official policy (e.g. AOU 1983; xxii) on when to consider names changes, and the first item under those guidelines begins as follows: "Retain well-established names for well known and widely distributed species, even if the group name or a modifier is not precisely accurate, universally appropriate, or descriptively the best possible."

I think these are excellent guidelines. Note that it is not a "rule," and I’m philosophically opposed to absolute rules, but a change to "Ring-billed Duck" would be a flagrant violation of those guidelines. Perhaps we should vote as a Committee whether to reaffirm this policy and avoid the hassle of dealing with a flood of proposals for "name improvement." One of the reasons for this committee is to safeguard stability of English names.

Note that the wording specifies "not precisely accurate."  My interpretation of this is that inaccurate or misleading names are thereby not covered. Therefore, names like Inca Dove, Pelagic Cormorant, Evening Grosbeak, Mountain Plover, and a few others would be unprotected by the guidelines, but everything else stays, perhaps even "Worm-eating" Warbler if lep larvae can be considered "worms" under the loosest of interpretations of "not precisely accurate," but most definitely covered is Ring-necked Duck.

NO. The author of this proposal makes a cogent argument, and I personally prefer "Ring-billed Duck," but I agree with others that we should follow our own guidelines for the sake of nomenclatural stability.

NO. I vote not to change the common name, in accord with long-standing NACC guidelines and majority consensus.

NO. I do not favor "fixing" names because of a perception that they somehow don’t describe the species well. Is Red-bellied Woodpecker next?  Since Magnolia Warbler has nothing to do with magnolias, do we need to change that, and so on. As noted by others, a change like this clearly violates our guidelines for changing English names.

NO. While I appreciate the proposer's desire to make a name a more accurate descriptor, the current English name reflects the Latin and has a very long standing in the literature. Stability and correspondence with the scientific name both cause me to choose not to make this change.

NO. As much as I personally like the name Ring-billed Duck, for consistency and stability we can't change the common name. The committee has a formal policy concerning this in the 1983 checklist. Perhaps this policy could be publicized more by putting on the web page to save everyone time in the future.

NO. However inappropriate the name is, the name has been used by ornithologists, birders, hunters, wildlife agencies, etc. for 100s of years. The species does have a ringed neck, it is just hard to see. It also is the only Aythya to have a neck ring, although other duck genera may sport them (like Mallards).  In most cases, do not think we should get into changing long-standing English names just because they are less than perfect.

NO. As others have pointed out, the competing issues of nomenclatural stability vs descriptive accuracy are really common in ornithology. The proposal is correct that 'ring-billed duck' is inherently a far better common name for this species. But the same would be true for any number of other species where alternative names are more accurate than their official names. Ironically, just before this proposal set went out a few weeks ago, a non-birder family member spotted our first ever yard-bird collaris on our backyard pond — and after looking it up on her own, gave me an earful on its inaccurate name, under exactly the same logic! I gave her the same response about nomenclatural stability.

NO. I think we do need standards that can be put to the public out when we consider English name changes. I will agree that Ring-billed Duck isn't a bad name, but it would change a well-established English name. If we lurch down the road of changing established English names in pursuit of finding the ideal English name, the changes would be just endless, and the result would just be confusion amongst the birding community. And, for what? Where would we start? Well, I would prefer Clay-collared Sparrow rather than Clay-colored Sparrow because one of the best field marks is the clay collar, especially useful on buffy fall birds. Mountain Plovers are not found in the mountains, they are found on the plains. So, with apologies to Clint, how about High Plains Drifters, to avoid confusion with Plains Wanderer? Nobody likes Green Heron and I have been asked endlessly where is the green? And why do you call it Purple Finch when they are not purple? How about Raspberry Finch? Sounds good to me. For me, I always get excited when I finally see that cinnamon or cinnamon-maroon neck ring on the Ring-necked Duck. You can see it if you get the right light. And I was simply thrilled when I saw that Purple Sandpipers really do have violet edges on the feathers on the upperparts. I learned with consternation that their close relative, Rock Sandpiper, has them too. On it goes.

If there is one thing that causes more consternation in the birding community than any other actions this Committee does, it is the changing of English names. I'll never hear the end of complaints about Oldsquaw to Long-tailed Duck and no one seems to know it was done for a conservation purpose, not for a desire to join the Anglo world. And, there is Pacific Wren.

For guidelines, I see two reasons for considering changing an English name. 1. When a split occurs and we need to find and an English name for one, or usually both (or more) of the taxa involved. 2.  When a species has a well-established English name that is of use elsewhere in the World, and is only of a more peripheral nature to North America, we should go with that name. Such examples included changing Rufous-necked Sandpiper (or Rufous-necked Stint) to Red-necked Stint, or Mongolian Plover to Lesser Sand-Plover. I would welcome revoking all of Eisenmann’s changes of Middle American English names, many (most?) in an effort to dump patronyms. But for goodness sakes, if we change English names we better explain our reasoning. After all the hoopla of complaints about Pacific Wren, I suggested in jest we use Pacific Rim Wren, and this is supported by the Commander Island birds being related to Aleutian birds. Even a better name if the Kuril Island birds are also more related to New World birds.


(a) Transfer Intermediate Egret Mesophoyx intermedia to Ardea
(b) Transfer Cattle Egret Bubulcus ibis to Ardea


YES - 3 without comment.

YES. Straightforward given the topologies.

YES. The phylogenetic data support this.

YES. I fully support this. In Asia where both Great and Intermediate Egrets are common, this is a difficult identification and one has to concentrate carefully on bill feathering and especially bill shape and bill tip color. Size is useful too when both are together, but many (most) of the Great Egrets there are smaller than Great Egrets we are used to (ssp. modesta). Importantly, Intermediate Egrets move with the same halting gait as other species in the genus Ardea.

YES. The treatment of Mesophoyx as a monotypic genus has never seemed reasonable to me, and the recent genetic work makes clear that it is embedded in Ardea.

YES. Merger of Mesophoyx into Ardea is required by the phylogenetic results.

YES on transfer of Intermediate Egret to Ardea. However, there are three allopatric taxa of "Intermediate Egret" with very different breeding plumages: African brachyrhyncha, Asian intermedia, and Australian plumipes; to me such pronounced differences in display ornamentation indicate they are different species, and HWB-BLI now considers them as such. Zhou et al. (2014), at least, sampled intermedia rather than the African or Australian taxa, and Huang et al. (2016) used Zhou’s data. The possibility thus arises that brachyrhyncha and/or plumipes might not be as closely related to intermedia as assumed (has anyone sequenced brachyrhyncha or plumipes?). I hope that the impending project will sample all of these! In any case, in the perhaps unlikely event that either of these taxa fall into another generic grouping (say Egretta), that can be dealt with later.

NO. If Bubulcus comes out within Ardea in phylogenies that includes more markers, this may necessitate changing some genus names within Ardea. If Bubulcus is sister to the rest of Ardea (sl), then just keep Bubulcus and Ardea (with intermedia). But if Bubulcus comes out as sister to a smaller clade within Ardea (sl), then I would be in favor of splitting off separate clades within Ardea as distinct genera, rather than lumping all within Ardea. If Bubulcus is sister to either the (alba + intermedia) clade or the (purpurata and the cinerea group) clade, I would be in favor of Casmerodius  (has priority over Mesophoyx) for alba + intermedia, Bubulcus for ibis, and Ardea for purpurata + cinerea group.         


NO - 1 without comment.

NO. Let’s wait for better taxon and character sampling which seems to be forthcoming (UCE study).

NO. This may seem inconsistent given the placement of Bubulcus on the tree relative to Mesophoyx, but to me at least it seems much more of an outlier morphologically.

NO (for now). Following the logic in the proposal.

NO. This one is not yet clear, and with an impending project that will hopefully shed light on this, I don't see any reason to make the decision now. Although body size is nearly worthless as a character to be used in delimitation of genera (e.g. think about Chloroceryle aenea vs. C. amazona; the former is smaller than some prey items of the latter), Cattle Egret is still such an outlier from the rest of Ardea that any merger must be backed by rock solid data.

NO on transfer of Cattle Egret. There seems to be no necessity of transferring it from Bubulcus to Ardea in order to attain monophyly, and the data are less clear, so I vote against doing so at this point.

NO. This is not straightfoward, Bubulcus ibis is sufficiently distinctive in morphology and behavior, and we should wait for the additional forthcoming data.

NO. Let's wait for the forthcoming data on the latter, as the proposal suggests.

NO. Cattle Egret would be such an outlier in Ardea (ecologically, structurally, vocally, etc.) that we should wait until we have solid evidence. Even then, I would opt for splitting it off an giving each clade within Ardea separate generic names.    

NO. This one doesn't make much sense. In addition to their different ecological niches, and their small size and peculiar bill feathering, these birds move in an entirely different manner. I guess they have to keep up with those cows (or water buffalo). If you lump this species in with Aredea, then you might as well lump Egretta too.


Revisit the proposed split of Circus cyaneus and Circus hudsonius

YES - 2 without comment.

YES. "Northern Harrier" for English name.

YES. I am convinced by the argument put forth in the proposal. I also favor using Northern Harrier for C. hudsonicus.

YES. I voted yes before, and think that the ecological and morphological difference give further support to treating them as separate species. Here is what I wrote for last year's vote: The question of import is whether hudsonius and cyaneus are differentiated enough to be reproductively isolated. The clade with these taxa in question also includes assimilis, maurus, and macrourus ("steppe harriers"). All are allopatric except macrourus and cyaneus (s.s.). All, except the all dark maurus, seem to be similar morphologically and in plumage, with gray males, some with various amounts of rufous markings. Though macrourus and cyaneus (s.s.) are in different parts of the clade, they look quite similar, yet are broadly sympatric in eastern Europe and west Asia. I therefore feel that the level of differentiation between cyaneus and hudsonius is also sufficient for reproductive isolation.

YES. Genetic distances at these shallow levels are not very reliable indicators of species limits. Further drilling down on a single locus (mtDNA) is not a productive way to delineate biological species. The lack of vocal differences evident from the proposal seems problematic, and habitat differences to me are not convincing as a species-limits phenomenon in this case (especially with the chance that it may be due in part to interspecific competition). But I think it is the additional morphological evidence, especially the differences in wing plumage, that cause me to agree with the proposal.

YES. To me it is clear these are distinct species. I also support the English names Hen Harrier for C. cyaneus and Northern Harrier for C. hudsonius, for reasons stated in the original proposal. If this split passes, the UAM wing of cyaneus will need reconfirmation.

YES. The molecular data are not overwhelming, and there are no obvious vocal differences, but the totality of evidence including differences in morphology, plumage, breeding habitat, behavior, and genetics - along with the lack of justification for lumping these by Peters - argues for recognizing these again as distinct species.

YES. This summary of the latest information and recent results has convinced me that burden-of-proof would fall on a their treatment as conspecific. Yet another lump that never should have happened.

YES. I'm not sure the new information is that much more compelling to split, but favored the split the last time and see no reason to change. I'll again repeat the inconsistent treatment with Cinerous Harrier Circus cinereus that is probably closer to Circus hudsonius than C. hudsonius is to C. cyaneus and again note Ferguson-Lees and Christie's (2001) comment under Northern Harrier whom treat it as a separate species (p. 486 under Geographical Variation): "Monotypic. Often treated as a race of Palearctic Hen Harrier, but adult is intermediate in various respects between that and Neotropical Cinerous Harrier and juvenile significantly different from juvenile Hen: all three could be considered allopatric and distinct races of one species or, the course followed here, three species forming a superspecies."

I was struck by the habitat differences for nesting. This is not a steppe or marsh nester. Perhaps it is competition from Western Marsh Harrier (Circus aeruginosus) or Eastern Marsh Harrier (Circus aeruginosus), but a simple glance at the Palearctic range indicates that this species must nest in many areas that no Northern Harrier would nest in. The Northern Harrier in terms of the north-south nesting range is a much more southerly nesting harrier than the Hen Harrier.

English namesI agree with the reasoning in this proposal. While Northern Harrier isn't the best name, it is pretty well established now, and Marsh Hawk doesn’t reflect the relationship to other Circus species and invites confusion with the two Palearctic marsh harrier species. And Hen Harrier is equally well-established for the English name. I entertained myself by trying to find a reference to them eating "hens" and didn't find any entries for this in the few sources I checked. It is sort of like trying to find a Common Moorhen on the moors. Good luck. 

North American RecordThe proposal outlines the one record. The evidence is a single salvaged wing picked up by David Sonneborn in June of 1999. It was a juvenile male (inference for species and sex by size), that measured 318 mm. It is at the University of Alaska Museum. DNA testing should be done on the bird, although the distance of less than 2% between these two taxa might make this problematical. DNA work on the one North American record of a juvenile specimen of Common Moorhen confirmed that identification (Withrow and Schwitters 2012). Even if the analysis and molecular testing in the end reveals a less than certain conclusion, the species would still qualify for the Appendix, and as noted, the range of Northern Harrier would be greatly constricted.

Ferguson-Lees, J., and D.A. Christie. 2001. Raptors of the World. Houghton Mifflin Company.
Withrow, J.J., and M.T. Schwitters. 2012. First North American record of the Common Moorhen (Gallinula chloropus) confirmed by molecular analysis. Western Birds 43:259-265.


Split Yellow-rumped Warbler Setophaga coronata into three species

YES - 1 without comment.

YES. A side note – The Toews paper (published in The Auk) states in the introduction "….the complex is currently treated as a single species, Setophaga coronata, by the American Ornithologists' Union, but as 3 species by the International Ornithological Committee (IOC); we used the IOC taxonomy in this article." I think AOU publications should follow AOU taxonomy. This point should to be made to the editor, if it hasn't already.

YES to split of goldmani, given how well-differentiated genetically and morphologically it is. A weak YES to split of coronatus and auduboni (despite the hybrid zone), given the indirect evidence for post-mating isolating mechanisms (which are after all isolating mechanisms), their different calls, and their differing morphology.

YES. First, I think the level of plumage and genetic differentiation between goldmani and other coronata taxa is comparable to differences among species in other closely related species groups in Setophaga. Therefore goldmani should be treated as a species. In regards to coronata/auduboni, the lack of assortative mating is troublesome, but I think the proposal does an adequate job to show that selection against hybrids is operating at some scale, as is selection for traits that are differentiating these taxa. This selection appears to be stable or increasing, which will further barriers to introgression through time.

YES. A strong yes, in fact. I feel that the weight of the evidence is now strongly in favor of this re-split. The genomic evidence is very strong that (for example) auduboni and coronata are well-differentiated, and that some regions of their genomes are under differential selection. Within the hybrid zone there appears to be no assortative mating (= little prezygotic isolation), but there does appear to be only limited genetic introgression and some form of selection against hybrids (= substantial postzygotic isolation). This scenario is the one theoretically expected in the early stages of full speciation under the BSC, where the postzygotic fitness consequences of hybridization impose selection (aka reinforcement) that leads to the later evolution of pre-mating isolation. Moreover, the hybrid zone itself is narrow and apparently stable, despite the vast population sizes of these birds and their very high dispersal potential. And phenotypically they are very easily distinguished. On an aside: the evidence is even stronger for recognizing goldmani as a full species.

NO. The problem here as I see it is the hybrid zone between coronata and auduboni. There is no evidence that there is assortative mating where they come together, and they hybridize like crazy. The evidence of postzygotic selection against hybrids (Toews and Irwin 2009) is important, and I agree it is likely that "some form of selection impedes the fusion of the Myrtle and Audubon’s forms." (T & I 2009:3057). But this is a long way from species-level stuff. Evidence of adaptation is not evidence of speciation, and I think that may be being confused here: a lot of adaptation occurs between populations that are not species. Selection for particular alleles across geographic space and a shift in such a selection regime across subspecies boundaries and non-assortative (and extensive) mating at a contact zone screams "subspecies" to me.

Brelsford & Irwin (2009) said it well in their title "Incipient speciation despite little assortative mating," and in the abstract: "Pairing data indicate that assortative mating is either very weak or absent…"  and "…there is moderate reproductive isolation between these populations…" Adaptation to different selection regimes (probably natural and sexual in this case) is great, and while reinforcement does appear to be occurring, it is only able to apparently stabilize what are actually pretty high rates of gene flow at least away from the contact zones." Toews et al. (2016) included multiple samples from each subspecies, but did not sample birds from the contact zone between S. c. coronata and S. c. auduboni." This leads to their uncertainty over whether more homogenized regions of the genome are due to hybridization or gene flow. Let me tell you from the specimens: gene flow will be responsible for a lot of it. I agree that "Clearly, performing additional genomic assays from birds across regions of sympatry will be beneficial." (Toews et al. 2016:708).

These populations are a wonderful example of the speciation process, but the birds' behavior in contact shows that they fit the concept of subspecies rather than the closer-to-evolutionary-independence we expect from full biological species. In sum, I do not consider there to be enough reproductive isolation yet established to make these anything more than a subspecies pair headed perhaps at some distant date to become (nearly) fully reproductively isolated. Saying that they are so now (biological species) suggests that we’re guessing a long way into the future, and that the substantial levels of gene flow occurring now are somehow not consequential. They may be genomically diagnosable, but they are far from genomically independent, given levels of gene flow.

Genetic differentiation of goldmani is expected for an isolated population smaller than the others, simply through drift (as Toews et al. 2016:706 noted). So genetic distinctiveness and isolation are not good metrics of limits of biological species, in my view. Phenotype needs to be more rigorously assessed in relation to other closely related members, and coronata and auduboni suggest well-differentiated subspecies are still not reproductively isolated. So as to whether goldmani is a species, I think we will want to know a great deal more.

NO. Maintain as one species, for now. I'm sorry, but I just can't get past the issue "of little assortative mating in the hybrid zone." If you believe in the BSC as I do, that's pretty much it. And I'm not sure what the "indirect evidence for selection against hybrids in the contact zone" means. I can readily identify these two ssp. groups. They not only look different, both in alternate and basic plumage, their call notes sound different. I think songs differ too, but both have a variety of songs. Here in the West, "Myrtles" prefer more mesic habitats. The motion alludes to the NACC having merged various taxa in this complex, notably hooveri with nominate coronata and memorablis with auduboni. I don’t think the NACC has taken any position on ssp. since 1957. I believe memorablis is mainly a size ssp. (larger), but plumage differences have been described from hooveri, especially in basic plumage.

I look at lots of Yellow-rumped Warblers here in the West, and have only a few times been pretty sure of hybrids. On the other hand, I don't look that carefully at every bird, and identifying a basic plumaged bird would be pretty problematical. I did see several hybrids in summer along the Stikine River, southeast Alaska, and I believe there are pretty much all hybrids along one river, I think in northern BC.

One thing that interests me is the disgestive system of this species. "Myrtles" are well-studied and they are able to digest bayberries, wax myrtle berries, poison ivy and poison oak berries, something that other wood warblers can't do. That's why "Myrtles" winter so far north, as far north as the southern Great Lakes and Nova Scotia and they can be abundant in mid-winter on the Mid-Atlantic coast. Are Audubon's able to digest these berries as easily with comparable plants in the West?

Anyway, for now, I'm comfortable with a one species concept. As for nigrifrons I would be very surprised that they merit being treated as a separate species. I've seen them in Chihuahua and yes they did look blacker, but they sounded like "Audubon's" farther north. The distance isn't that far from the Sky Islands of the Southwest, where intergrades have been noted in southwest New Mexico and southeast Arizona. As for goldmani this is an interesting case that merits further study. I'm told that folks seeing them in Guatemala report them giving very different songs, but don't know if there are recordings (maybe some put on a web site?). I did not see them on the hike for the Horned Guans in southwest Chiapas, so guess they occur elsewhere in Chiapas. The BNA account (Hunt and Flaspohler 1998) state: "In this subspecies, Alternate and Basic plumages of adult males nearly identical; there may be no Prealternate molt (Hubbard 1970, 1980)."  If that's true, it certainly is suggestive for separate species status.

Hunt, P.D., and D.J. Flaspohler. 1998. Yellow-rumped Warbler (Dendroica coronate). In The Birds of North America, No. 376 (A. Poole and F. Gill, eds.).  The Birds of North America, Inc., Philadelphia, PA.

NO. At the outset, I would like to make it clear that I have always "disliked" the Myrtle-Audubon’s lump because in my tidy little worldview, if I can identify two taxa by call note as far away as I can see them, they "have to be" species.  In fact, to this day, I use "Myrtle" and "Audubon’s" in my field notes etc. Also at the outset, I find these genetic data interesting and important to understanding the history and process of diversification, and I applaud the authors of the recent papers for making substantial progress. But application of my tidy little worldview to real world situations is, predictably, not always tidy, and application of genetic data to taxonomy is not always straightforward.

Specifically, as confirmed by these recent papers, there is no evidence for assortative mating at the Audubon’s-Myrtle contact zone. Hubbard's original results based on phenotype are confirmed by genetic analyses. Despite the call note differences and fairly conspicuous plumage differences, they are not isolating mechanisms – the two taxa treat each other as "same" where given the chance to show us the relevance of these characters --- these differences evidently make no difference when it comes to mate choice. So, if these two taxa don’t treat each other as different species (my version of BSC), why should we? Perhaps rescuing my tidy worldview is that as far as is known songs of Audubon's and Myrtle are not readily distinguishable, although I don't think this has been adequately studied. Thus, perhaps it isn't a surprise that the two are not reproductively isolated. Toews et al. (2016) used song playback to capture individuals, and I wish they had reported on the details of this, i.e. whether responses were equivalent, etc.

The authors found evidence for selection against hybrids away from the contact zone and interpret that as evidence for reproductive isolation. This is the same interpretation of the BSC that, unfortunately, allowed the Scrub Jay split to pass, a result with which I strongly disagree. Neglected in this interpretation of the BSC is that there is presumably selection against intergrades away from the contact zone in EVERY parapatric subspecies pair. Otherwise, there would be a smooth cline between subspecies taxa and thus  …. they would not be treated as valid subspecies. Presumably natural selection favors the phenotype-genotype combination that characterizes the populations of diagnosable subspecies away from zones of intergradation. The only "escape clause" from this conclusion is that the situation is not in equilibrium. However, because most subspecies follow biogeographic patterns, selection favoring those phenotype-genotype plateaus is implied. Therefore, the phenotypic and genetic results of the recent studies favor ranking them as subspecies, not species, opposite of their published recommendations and those of the proposal. In other words, if Myrtle and Audubon’s are ranked as species under this interpretation of the BSC, then all parapatric, diagnosable subspecies with zones of introgression should also be elevated to species rank.

As for ranking the allotaxa goldmani and nigrifrons as separate species, this would require showing that these taxa have diverged from coronata and each other in song more so than coronata and auduboni have, preferably also with playback trials. Such trials and comparative analyses of vocalizations have obvious problems in interpretation … but so does every set of criteria for species delimitation. What song and playback trials have going for them is that they consistently predict absence or presence of free gene flow between parapatric and sympatric taxa --- thus, they work, empirically, for predicting the all-important process of gene flow (as in the Toews-Irwin study of Winter vs. Pacific wrens). As for the problems with use of song in oscines because it is "learned," this oversimplification should not be perpetuated. First, oscines are genetically hard-wired to learn there "own" songs --- otherwise, for example, in areas where multiple wood-warblers are syntopic, they would all just sing the same Esperanto song. Second, experiments show that some components of song are genetically determined: genetics constrains which components of song are learned vs. inherited. I look forward to seeing published results on song differences (as hinted in the proposal).

I end with a string of minor comments on the evidence. (1) Because as far as I can tell, no specimens were collected, all interpretations of phenotype are evidently based on in-hand inspection in the field; perhaps digging into some of the background studies would reveal that there are archived photos for each individual? (2) As for the finding that nigrifrons and goldmani are reciprocally monophyletic, although this has an awesome ring to it, keep in mind that it is based on a limited N of individuals and loci, and so in any such statements, one additional sample might erase such proclamations, i.e. all such proclamations should be accompanied with the qualifier "based on N individuals and loci." (3) As for the general finding that all four taxa are genetically defined, we "already know this" assuming that the plumage characters that define the four taxa have a genetic basis. That neutral loci also reflect the genetic differences underlying the phenotypic differences is interesting but taxonomically not particularly relevant. (4) That there is no gene flow between auduboni and nigrifrons despite nonbreeding sympatry is expected; the only wintering auduboni that might remain in the range of nigrifrons during the breeding season are probably defective individuals that would be unlikely to breed, and even if they did, the rarity of those events might make them difficult to detect without much larger N. (5) I really look forward to studies of the potential contact zones between auduboni and nigrifrons.

NO. After reading the commentary from both the pro-split and pro-lump camps, I think that leaving these taxa together best represents the admittedly complex and somewhat intermediate situation that these taxa represent. I am open to being persuaded otherwise, however.

NO. Like the other "No" votes here, I think that the lack of assortative mating in the contact zone between coronata and auduboni argues against recognizing them as biological species - along with the lack of known song differences. It's unfortunate that the genomic data didn't include sampling in/near the contact zone. I wonder why those samples were not included? I could possibly be convinced to split goldmani given genetic and morphologic differences, but would like to see the unpublished data on vocal differences.


Split Willet Tringa semipalmata into two species

YES. I listened to Xeno-canto and the calls do appear to be higher pitched for the nominate ssp.

YES. I vote for this split based on comments by other committee members. I like the suggestion of Saltmarsh vs. Prairie willets as English names.

YES. It's always hard to evaluate BSC in allopatric cases like this, but in my mind the genetics, morphology, vocalizations, and the playback that has been done points more to a case of two species than two subspecies.

YES, barely. This one is in the uncertain zone, but that is how the biology of speciation works. The newer genetic/genomic data suggests that the two forms have been isolated for a reasonably long while, although I might have expected them to have had more gene exchange during colder periods of the recent Pleistocene when both forms were undoubtedly pushed south. The kicker for me, though, is the 1998 paper on call discrimination, in combination with this newer information. I've gone back and looked at that playback paper and it reports strong (but not perfect) discrimination of the "pill-will-willet" call by eastern willets (around 20% response to playbacks of the western call, around 80% response to playbacks of the eastern call). Replicating the experiment in the west would certainly be a good thing (doing this thoroughly on both coasts would actually make a great undergrad honors thesis for somebody…).

YES. Three lines of evidence point to treating inornata and semipalmata as separate species. 1) These taxa are adequately differentiated in both morphology and genetics for species status (comparable to Spotted/Common Sandpiper or the tattlers). 2) These taxa are very different in breeding habitat. Although beach/salt marsh habitat abounds in the West, inornatus  does not use this habitat for breeding. This suggests that even if semipalmatus (s.s.) expanded its range and bred in similar habitat western North America, it would still be isolated from breeding inornatus. 3) The vocalizations are different and diagnosable, maybe not as dramatically as the tattlers, but more so than the whimberels. As much as playback experiments would be icing on the cake, we have not relied on such trials for other closely related species pairs. 

I would like to propose a different set of English names as Eastern Willet and Western Willet are dull and not very descriptive: Saltmarsh Willet for semipalmatus, and Prairie Willet for inornatus (thanks to Adam Kent for the suggestion). If it is felt that this is stretching the definition of term "prairie," another suggestion would be Plains Willet, which works both for its breeding area, and also because inornatus is plain. Although these terms are accurate only during the breeding season, so are "Eastern" and "Western."

YES. I've been visiting the Upper Texas Coast nearly every spring since the early 1980's. The "Eastern" Willets are obvious as they are display flight and vigorously calling "pill-will-et, pill-will-et" and on and on, or they are sitting on fence posts. Sometimes they are with other shorebirds, including "Western Willets."  I've never seen them interact in a friendly manner and really, why should they? In the flooded rice fields some five to 20 miles inland, I often see Willets, but only "Western Willets." Sometimes they are 50 at a time.

I'm happy with the split given the widely separated breeding ranges. The hard part will be determining winter ranges. I'm told "Eastern Willets" winter largely in South America. Are there any "Western Willets" there, and are there are any "Easterns" in winter in Mexico (especially the Yucatan), or the West Indies? There are vagrant record of Willets from Europe and the Azores. Sorting out the distribution and the records of vagrancy will take some time. I've been told that breeders arrive on the Texas coast by mid-March and are mostly gone by mid-September. 

English names Prairie Willet for inornata is an interesting suggestion, except they are Plains (Great Plains) and Great Basin nesters. I think "Eastern" and "Western" are pretty well-established in the birding world by now and they do apply nicely for the breeding ranges. Birders are learning quickly that "Eastern" birds don't winter in North America, while "Western" birds winter commonly on the southern Atlantic and Gulf coasts. 

NO - 1 without comment.

NO. To me, the data as currently presented seem more consistent with taxa to be treated as well-differentiated subspecies than as distinct species.

NO. The genomic case looks strong, and I have no doubt given their long-distance movements that they have sufficient opportunity to interbreed. But a lack thus far of definitive phenotypic separation (and I don't include distribution in this category) makes a good case for waiting for more information.

NO (for now). This is a borderline case. The two subspecies differ morphologically, genetically, and in some vocalizations. However, the geographic sampling for genetic data was small (only 30 individuals total, with a mixture of breeding and non-breeding birds), and the playback experiments in the 1998 study showed discrimination in only one vocalization type but not in others that were tested. That paper reported a gradual divergence in song characteristics that "has resulted in song discrimination and incomplete reproductive isolation in Eastern Willets." I agree with others that more data are needed before making this split.

NO. I think we should abide by the cautious conclusions of the paper itself, namely additional data are needed. Specifically, the vocal data are suggestive but equivocal, and additional, reciprocal playback trials are needed. Also, these two are likely closer genetically than any other two sister taxa in shorebirds ranked at the species level, and all of the sister taxa of shorebirds (including tringines) that I can think of, no matter how similar morphologically, differ in flight calls: Spotted vs. Common sandpipers, Long-billed vs. Short-billed dowitchers, Wandering vs. Gray-tailed tattlers. There are hints that the two willets differ in flight calls – let's see this documented, including reciprocal playbacks, given how marginally different the birds are. As for the bill shape differences, these sort of differences are evident between sexes within a species in some sandpipers, e.g. Calidris mauri, C. alpina, Limnodromus spp. Notice also that the morphological differences are overlapping, not diagnostic, and that even with a discriminant analysis, the two taxa are not 100% diagnosable (probably due to the inclusion of mostly Gulf Coast individuals in the morphometrics, which appear to be more similar to Westerns than are the Atlantic birds). The degree of plumage difference between the two is also matched among subspecies of L. griseus and C. ptilocnemis, for example. The estimated divergence time (700,000 years) and 0.85% sequence fits better with subspecies rank (although see pp 603-604 concerning problems with single locus comparisons). The proposal mentions no evidence for gene flow as providing support for two species. With their breeding ranges separated by 1600 km, any result other than that would be a shocker. Although the differences in salinity between the typical breeding habitats of the two willets might be used by some as support for the two populations being on different evolutionary trajectories, keep in mind that the inornatus group spends the nonbreeding season largely in brackish or saltwater habitats.

There are published December records of semipalmatus for Florida that should be confirmed before further confirmation bias generates allopatry in winter ranges. As for the differences in timing of breeding and habitat, we have the same thing here with resident coastal subspecies of Marsh Wrens, singing and breeding (presumably) while the much larger population of interior subspecies that winters here is still present and widespread. Finally, there is morphological overall between the subspecies to the point that PCA cannot distinguish the two 100% of the time. The Gulf of Mexico population is larger in size than the Atlantic population that birders fixate on. Anyway, I remain agnostic on the issue and maintain that we need better vocal data before splitting, given that all other species pairs that I can think of in Scolopacidae have obvious vocal differences (e.g., tattlers, Actitis, SB vs. LB dowitchers).


Modify our treatment of juncos:
(a) Recognize bairdi as a species
(b) Recognize alticola as a species
(c) Lump phaeonotus and hyemalis


YES - 2 without comment.

YES. Straightforward proposal.

YES. Vocal, morphologic, and genetic differences support this split.

YES. There is now good and complementary evidence that bairdi is well-differentiated from the other juncos.

YES. Genetic, morphological, and vocal differences all argue for species status.

YES. No reservation to splitting bairdi for reasons in the proposal. Nice to see how clear-cut this is. I agree with Baird's Junco, as it is already in use and Baird deserves it.

YES. Seems straightforward.

YES. I barely vote yes on this proposal. I am not seeing discussion of song learning in oscine passerines, clear focus on characteristics that are conserved despite learning, or a careful contrast with other juncos in the degree of difference so we can have some confidence that these levels of differentiation indicate full biological species. I don’t consider mtDNA to be a reliable species delimiter, and while the song and morphological differences are certainly intriguing, are they greater than that seen between hybridizing forms? In going to Piepelow & Francis (2011) and xeno-canto, I think the answer is probably yes; the song is quite strikingly different. As we continue to increase our uses of song divergence in passerines it would be really good to focus on degrees of difference in conserved characters relative to accepted full species.

YES. As outlined in the proposal, multiple lines of evidence support this split. Great to see the vocal distinctiveness noted by Howell and Webb (1995) quantified by Pieplow and Francis (2011). That is nail-in-coffin evidence in my view.

(b) & (c)

NO - 1 without comment.

NO. My vote is based on the proposal, but we should consider a new paper in Molecular Ecology with a lot more data to address Junco relationships: In the new paper, fulvescens from Chiapis is sister to alticola in a SNP tree, whereas in the mtDNA phylogeny alticola clusters with insularis. The authors suggest species status might be warranted for both alticola and fulvescens.

NO. Requires further study.

NO. These cases are weaker and require further work.

NO. I’ll follow the proposal recommendations.

NO. I consider my votes to be the conservative approach given the state of information at this moment. I suspect that we are close to having afunctional genetic basis for understanding many of the coloration traits that mix-and-match among these forms. If so, that will pose us some new challenges about how we use differentiation in particular genes of known effect to inform decisions about species limits … but this is something that we will need to wrestle with in the context of each individual situation. Interesting times…

NO. I think there are a number of possibilities for re-aligning the taxa of juncos in North America north of Mexico. The phaeonotus/dorsalis/caniceps set seems particularly open to reassessment. I seriously doubt that treating all of these juncos as one species is the best treatment of the group. My guess is that dorsalis probably goes with phaeonotus, not sure about caniceps. The lack of so many taxa in this study, I think makes it premature to make any change that this point.

NO. I would like to see the mtDNA data backed up by nuclear data. They may be much more closely related to mainland phaeonotus if introgression is skewed by sexes. Junco phaeonotus and hyemalis come close enough to each other during the breeding range to examine the genetics (and morphology and vocalizations) of reproductive isolation more closely.

NO. Rationale presented in the proposal. These situations require further study, and any decision at this point is premature.

NO. Behavior (more walking locomotion in J. phaeonotus) and especially song would mitigate any lumping of J. phaeonotus and J. hyemalis. The question for me for several decades is what about J. h. dorsalis, the "Red-backed Junco." It is found from near Kingman and Flagstaff and then southeast along the Mogollon Rim across the southern half of New Mexico to the Guadalupe Mountains of west Texas. They are pretty sedentary (like Yellow-eyed) with elevational movements. I have twice recorded dorsalis in the Huachuca Mountains. My first prolonged encounter with this taxon was decades ago in May in the Guadalupe Mountains. I heard multiples singing and thought they sounded like Yellow-eyed Juncos, a species that shouldn’t be there. So, I played a tape of Yellow-eyed Junco and bang birds roared in. Except, these birds had dark eyes. They were dorsalis. I have wondered ever since if dorsalis might be a dark eyed ssp. of Yellow-eyed Junco, but I think the song might be variable through their range, or in other words maybe birds in Flagstaff sound more like Dark-eyed Juncos. Obviously more study is needed. Not sure what the molecular results are on dorsalis. I can’t remember if anything is published.



Note from Chair: One committee member questioned (a) the placement of erythropus deep within Tringa, (b) the placement of Xenus cinereus closer to Phalaropus than to Actitis or Tringa, and (c) the placement of Numenius tenuirostris following arquata, thus separating madagascariensis from arquata.  My thoughts on these are as follows:

(a) The molecular data are strong in placing erythropus deep within Tringa. I don’t think there’s anything to be done in this case without disregarding the genetic data, which are the basis for the entire linear sequence. 

(b) Support for relationships among XenusPhalaropusActitis, and Tringa is poor. We could treat these as four clades of unresolved relationships and then simply place them in the linear sequence going from least diverse to most diverse clade. This would result in the sequence XenusActitisPhalaropusTringa. We could also consider some other alternative.

(c) There were no genetic data for Numenius tenuirostris. The proposal states that "placement of N. tenuirostris follows traditional placement as sister to N. arquata" – this gave us the sequence americanusmadagascariensistenuirostrisarquata. This is our current sequence except that americanus is last in the current sequence (i.e., sequence of madagascariensistenuirostrisarquata is the same). An alternative sequence that was proposed is americanus, madagascariensis, arquatatenuirostris because of the phenotypic similarity of madagascariensis and arquata. I believe the sequence of presumed sister taxa tenuirostris and arquata conforms to the Old World sequencing convention of "Europe first."

YES - 3 without comment.

YES. Seems uncontroversial. Note that if proposal 5 to resurrect Steganopus passes, that name will need to be fixed and the genus entry added.

YES, but with some questions. Within Tringa, there are some pretty obvious sister species pairs. These are the two tattler species, Green and Solitary Sandpiper, and Common Greenshank and Greater Yellowlegs. Beyond that, for me there is no intuitive sequence. One species that has always been an outlier for me is Spotted Redshank (Tringa erythropus). The call note of that species sounds nearly identical to my ear as a Semipalmated Plover (Chradrius semipalmatus). It really sounds very different from any other Tringa. Does it really belong between Willet and Greater Yellowlegs? More troubling is the placement of Xenus cinereus (Terek Sandpiper). It does not seem intuitively obvious to me that it is more closely related to the three phalarope species than to Tringa and to the genus Actitis. I’ve always wondered if Terek might be a Tringa. Their call is very similar to Wandering Tattler. 

Another issue is with the linear sequence within Numenius. Far Eastern Curlew (Numenius madagasgariensis and Eurasian Curlew (Numenius arquata) have always struck me as very similar when not seen in flight. In fact, I can’t tell them apart when sitting, although some can. In Southeast Asia, they are often associating together. Hayman et al. (1986) describes their calls as pretty similar. By the present suggested arrangement the order would be Long-billed, Far Eastern, Slender-billed, and Eurasian. How about Long-billed, Far Eastern, Eurasian, and Slender-billed? That pairs Far Eastern with Eurasian, and still has Slender-billed with Eurasian. I wonder how extensive the genetic testing was on Slender-billed? The species has likely been extinct for over two decades. (Hayman, P., J. Marchant, and T. Praeter. 1986. Shorebirds. Houghton Mifflin Company).

YES. Re: the Chair's comment (b): This seems like the prudent thing to do at this time. Polytomy.

YES. Re: the Chair's comments: (a) Agreed. (b) This seems fine to me, as long as we make it clear what we are doing. (c) I think that we should stick with our conventional way of doing things (have we used phenotypic similarity as a basis for sequence before?). Whatever we do, we need to make the rationale clear.

YES. Re: the Chair's comments: (a) stat; (b) I don’t care, provided we can explain our departure; and (c) I don’t think we can inject phenotypic similarity here when it has not been part of what I have taken to be our standard tree-based sequence approach. But I’d be happy to change that whole approach, provided we explain our reasoning. I have long thought our adherence to mirroring tree sequences to be rather frustrating, because we put ourselves at the mercy of tree-building algorithms that are agnostic with respect to flipping nodes around and unaffected by information like phenotype that are not part of building them. But how far do we want to go in artistically interpreting them? Here we are considering adding a lot of additional interpretation without room in our traditional supplement format to explain departures from a published "standard."

YES. Unfortunately, we just revised the sequence! Should have been more careful. Re: the Chair's comment (b): This is okay as long as the rationale is explicit. Re: the Chair's comment (c): Our sequence now has americanus last because Mayr and Short (1970) said that it was a possible superspecies with arquata, but that is not what Gibson and Baker show (madagascarensis and arquata are sisters, but tenuirostris not included).  I am not sure who has hypothesized that arquata and tenuirostris are sisters, but that seems to be evident in most sequences. If they are and using "Europe first" then arquata should precede tenuirostris. If madagascarensis and arquata are sisters (is this what Jon is proposing?), then arquata should be first precede madagascarensis, with tenuirostris before the latter. As I understand it, arquata and tenuirostris are sisters and "Europe first", so americanus, madagascarensis, arquata, tenuirostris.

YES. I continue to be impressed by the rather distant relationship between the two yellowlegs despite their superficial similarity. Re: the Chair's comment (b): I have gone back and looked at the tree, and the node that supports a Xenus-Phalaropus sister relationship is indeed poor: 0.56 posterior probability. Thus, it is best treated IMO as a polytomy that escapes the strict rules of sequencing. Therefore, in the interests of stability as well as the near absence of support for a strong relationship between Xenus and Phalaropus, I think we have to retreat to a more conservative approach and NOT have the phalaropes interned between Xenus and Actitis + Tringa. To do otherwise is risky in over-extending the strength of the data that supports that move. If anyone knows anything about Xenus that suggests a relationship to phalaropes beyond that weakly supported node, speak up. (c): Sounds good to me.