Home About Committees North American Classification Committee Current & Prior Proposals 2022 Proposals Comments 2022-B

Comments 2022-B

2022-B-1: Remove recognition of Loxia sinesciuris (Cassia Crossbill) as a distinct species

YES. While both the Hill and Powers and Benkman et al. papers raise excellent points (and get bogged down in places that are not as strong), in the end taxonomic application of subspecies/ecotype is a better fit to these animals as it is predominantly used in other taxa where situations like this are more common (e.g., plants, insects). So in applying taxonomic concepts and labels to the results I find the genomic evidence to suggest that these are strongly differentiating populations best labeled as subspecies or ecotypes.

Directly measuring and estimating levels of reproductive isolation in living animals is hard work, and Benkman et al. have done a terrific job of this. This is a really great system for our understanding of ecological speciation. There is no doubt that high levels of RI have been achieved (though there are also appreciable levels of disassortative mating). But it appears from the genomic data that these levels are not yet convincingly causing the “essentially reproductively isolated” level of lineage independence required by the BSC. The apparent importance of cultural evolution in this system is also problematic. That such a malleable factor is so important in promoting RI in the present means continued evolutionary independence relies on a rather readily reversible isolating mechanism. Rates of measured change in decades that happen to be going in the right direction right now are the opposite of comforting.

The genetic data are really interesting, but nothing there demonstrates species status. First, monophyly at a small portion of the genome is not a species limit criterion. Nor is genetic distinctness. Nor are PCA results. Distance values are not very useful here. We’re left relying on “nearly complete reproductive isolation” measured with the animals and inferred in the genetics in a place of sympatry. This is a powerful demonstration of the process of ecological speciation, aided considerably by cultural evolution, it seems. But it does not look to me like a) reproductive isolation is complete, and b) that it has achieved sufficiently high levels for sufficiently long to confidently call it a biological species. Further, if we look more broadly across the red crossbills (as I appreciate H&P doing), it seems likely that these sorts of situations have generally not resulted in long-term biological species emerging, but that they are fragile in evolutionary time. Cultural evolution alone creates such flexibility, but likely all it would take is a pronounced ecological change, like red squirrels colonizing, to cause this system to collapse back into the lower divergence levels of red crossbill ecotypes. Regardless of the taxonomic determinations, it is looking like the red crossbill complex is a syngameon not yet really producing evolutionarily long-term independence of any single lineage. And as I look more broadly across taxa and consider how we have treated situations like this, subspecies and ecotypes fit a lot better. We have plant and insect (and even human) populations that are more diagnosable and yet retain more widely recognized shared species attributes.

YES. I need to start off by indicating that I have a vested financial interest in this issue. After the split, I organized and now lead a Wings trip to southern Idaho. The South Hills and sometimes the Albion Mountains of southern Idaho in Twin Falls and Cassia counties. These “sky islands” are beautiful and fascinating with other interesting issues to explore not related to Loxia. The juncos from those two ranges don’t seem to align to what Miller (1941) relates in terms of the taxa caniceps and mearnsi. I co-lead these tours with Austin Young, a keen field ornithologist and graduate student at Idaho State in Pocatello. He has tutored me on the calls of Loxia sinesciurus and how they differ. With my declining ears, I struggle. To me they don’t differ greatly from type 2’s (yellow pine types), seemingly less so than the small type 3’s and type 10’s, the small ones with smaller bills. Austin has told me that the differences are more obvious looking at a spectrogram. 

I have twice previously voted against the split, not necessarily because I don’t think they are separate species, but I preferred a comprehensive approach to Loxia curvirostra. In the New World we have some eleven types of Red Crossbills that are separable by call. And then we have the Old World which I haven’t begun to look at in any detail. But allopatric populations in Morocco, the Balearic Islands, Corsica, northwest Africa, the Himalayas, south-central Vietnam and northern Luzon, the Philippines, all suggest the differences in calls will likely be distinct, as will be genetic differences. The splits thus far, especially Scottish Crossbill (L. scotica) haven’t been met with much enthusiasm. The last time we voted on this I believe the only dissenters were myself and Rising. 

I can appreciate that now we have split Cassia Crossbill, there is reluctance to go back, hence my vote is not particularly strong. It’s more of a sentiment that I wish we hadn’t split them to begin with. It puzzles me why the easy lift hasn’t been taken, splitting Loxia leucoptera into two species (New World nominate leucoptera and Old World bifasciata). These two are strongly allopatric, have different bill shapes and plumage, and most importantly strikingly different vocalizations. We have already split the Hispaniola Crossbill off; somehow the New World/Old World birds have been partly/largely ignored.


YES. Although I voted to split these initially, and I do not have a problem that sinesciuris is currently reproductively isolated from the type-2 and type-5 curvirostris, I think that long-term reproductive isolation has yet to be established. Another voter sees the same thing: reproductive isolation is currently being maintained by mostly pre-zygotic cultural characters (song) and the current ecological conditions (lack of red squirrels resulting in serotinous cones that have coevolved with sinesciuris). In my view, it wouldn’t take much environmental change to upset this delicate balance maintaining reproductive isolation, and the benefits to assortative mating would disappear. I think that the Biological Species Concept requires a more permanent stoppage of gene flow.

YES. This marks the second time I’ve reversed my vote on this one, which has to be one of the vexing situations in North American birds in terms of trying to apply taxonomic ranks. My “yes” vote is based more on instinct than data. If Cassia Crossbill fits the BSC definition of a species, then we have perhaps the “youngest” species in ornithology, as emphasized in the proposal. Although the current data seem sufficient to accord species rank, I am concerned that the differences themselves are just so minor (a subtle difference in call note and bill measurements) that the current situation is fragile with respect to persistence. As for call notes, I can’t think of a taxon (Carduelinae) in which learning rather than genetics is more likely to play a role. I recognize that this a somewhat weak and subjective opinion, but given that the proposal is going to fail given the votes so far, I see no harm in expressing this instinctive reluctance. 


NO. After reading the proposal and the response from Benkman (who knows these birds better than anyone), I am convinced that we should retain Cassia Crossbill as a distinct species. The argument for conspecificity is based in part on the premise that the supposed pace of speciation in Cassia Crossbill is unprecedented in North American avian taxonomy, and that all speciation must meet the same criteria. This case must be evaluated on its own merits, and the available evidence presented by Benkman et al. warrant recognition of Cassia Crossbill as a distinct species.

NO. When the split of Cassia Crossbill (Loxia sinesciurus) from Red Crossbill (L. curvirostra) passed in 2017, the genetic, morphological, and voice differences, along with limited gene flow between Cassia and Red crossbills despite opportunities to mate, were highly valued to accept the split. The new proposal to lump the two species of crossbills, although providing highly detailed re-interpretation of previous data and research, does not present new information from what was evaluated by the NACC five years ago.

The authors of the proposal mention that even when Cassia Crossbill has a unique and distinctive call type, birds can modify calls during their lifetime. However, they do not report evidence that Cassia Crossbill individuals are doing that. Benkman, the author of the response, reports that 0.36% of the birds categorized as Cassia Crossbills changed their calls to that of another species. Additionally, the authors of the proposal write that in the same way as Red Crossbill individuals move to Cassia Crossbill’s range, Cassia Crossbill individuals could move to Red Crossbill´s range and interbreed there; there is no evidence provided on this point either. The response to the proposal mentions that none of over 3000 color-banded Cassia Crossbills in the South Hills has been detected outside of the South Hills.

Given that there is no new information supporting the removal of Cassia Crossbill as a distinct species, and Benkman provides new information in favor of the recognition of Cassia Crossbill as a separate species from Red Crossbill, I vote for sustaining the decision made by the NACC in 2017. The study of the complete range of the Red Crossbill is in need. Studies including Mexican and Central American populations are due.

NO. This is an immensely fascinating system, and one that I have been following for many years. After reading both Hill and Powers’ proposal, and Benkman’s response, I find that I agree with the other committee members who have voted to reject re-lumping Cassia Crossbill with Red Crossbill. It seems to me that much of the proposal to lump centers on a very specific interpretation of the Biological Species Concept, and one that the committee already departs from when addressing species in other avian systems. While speciation on the time scale involved for these crossbills is indeed unprecedented, to me that is not a reason for not recognizing them as distinct species. I think that Benkman provides ample evidence to show that Cassia Crossbill is reproductively isolated from other Red Crossbills at a level that many other species that we recognize are, and that multiple factors contribute to that isolation. 

NO. I doubt there will ever be a strict consensus on species status of Loxia sinesciurus, as reflected in the 8-2 vote that passed its species status. The reinterpretation presented in this proposal suggests that reproductive isolation of sinesciurus is rather incomplete and that sinesciurus is better treated as a locally adapted ecotype rather than a full species. I generally agree that evidence of PCA clustering from thousands of SNPs and Fst outliers with whole genomes are not sufficient for species status alone, but sinesciurus has been subject to long-term field studies that clarify the special evolutionary and ecological dynamics at play in this system. Overall, I find the evidence for assortative mating and loss of hybrid fitness convincing. 

While I agree that sinesciurus is an exceptional case of speciation in terms of its pace and recency, I don’t share the proposal’s concerns that recognizing sinesciurus will open the floodgates for locally adapted populations in other lineages to be recognized as full species. Rather, the decades of careful field observations paired with whole-genome data suggest sinesciurus is a very recent speciation event where reproductive isolation has evolved rapidly due to extremely strong ecological pressures decreasing hybrid fitness and cultural evolution promoting assortative mating. 

If red squirrels were to recolonize the South Hills and Albion Mountains, I agree that sinesciurus would likely be subsumed by or replaced with Call 5 & 2 types of Red Crossbill. However, I see our [NACC’s] task as to assess species limits at this point in time, and to me, the evidence suggests the recent accrual of substantial (but perhaps not 100% complete) reproductive isolation. The genomic patterns are similar to those observed in a growing number of comprehensive studies of other exceptionally rapid radiations, such as Sporophila seedeaters and Lake Tangyanika cichlids. Furthermore, although I agree with the proposal that mitonuclear incompatibilities are likely a common feature of many speciation events, they are not required for speciation to occur under the BSC. I agree with other NACC members that a complex-wide study of species limits within Loxia is long overdue.

NO. I vote against relumping the Cassia Crossbill. I agree that we should be assessing present species limits (as demonstrated by Benkman et al.’s impressive studies), not what they might be in the future if, for example, red squirrels move in. Nor can we apply a one-size-fits-all species concept. I also agree that species limits in crossbills need much further work (as does the Pine Grosbeak, I’d say a much easier split). 

NO. After reading all the arguments, my vote remains unchanged from 2017. There is enough genomic and field-based evidence to recognize these as species, even if they don’t follow a typical avian pattern.

2022-B-2: Recognize the genus Ramosomyia for “Leucolia” viridifrons (Green-fronted Hummingbird) and “L.” violiceps (Violet-crowned Hummingbird)

YES. 

YES. Clearly Leucolia cannot be used, and no other name applying to these species appears to exist.

YES. This change seems necessary as noted in the proposal.

YES. The proposal is clear on the change of the generic name.

YES. This seems to be appropriate taxonomic bookkeeping. But I will use the opportunity to reiterate that we have drastically oversplit hummingbirds at the generic level compared to other avian orders.

YES. As described in the proposal, it is a necessary change.

YES. Since the type of Leucolia does not belong with these two species, that name cannot be applied to viridifrons and violiceps, so a new name is needed.

YES. Reasons are outlined in the proposal. 

YES. As described in the proposal, a necessary change.

YES. As the type specimen belongs to other species, this change is required.

YES. As described in the proposal, taxonomic housekeeping is necessary in this case. 

2022-B-3: Transfer Myrmeciza zeledoni (Zeledon’s Antbird) to Hafferia

YES. The clade containing zeledoni is clearly close to Hafferia, and does not seem obviously to require its own genus. The other option of a highly polytypic genus containing everything in Gymnocichla seems overlumped and inconsistent with generic limits in the group. 

YES. This seems like the best option and I don’t see any reason not to follow the SACC in transferring M. zeledoni to Hafferia.

YES. I agree with the recommendation of the proposal to follow SACC and transfer M. zeledoni to Hafferia; one of the reasons is because the clade that contains zeledoni is close to Hafferia.

YES. I agree with following SACC and transferring Myrmeciza zeledoni to Hafferia. M. zeledoni is closely related to Hafferia, and using Hafferia could result in a more stable classification in the long term.

YES. I particularly appreciated Gustavo Bravo’s comments.

YES.  This follows the SACC.

YES. This change will bring NACC into agreement with SACC. 

YES. Reasons are given in the proposal.

YES. I see little reason to break from what the SACC already decided. The species in Hafferia are rather structurally and behaviorally homogeneous.

YES. Follow SACC’s lead here.

YES. I voted for this change in 2020 and continue to think this remains the best course. Matches with SACC lead and new data. 

2022-B-4: Treat Chondrohierax wilsonii (Cuban Kite) as a separate species from C. uncinatus (Hook-billed Kite)

YES. This is a well-drafted motion (and argument). I agree that the arguments of Amadon are insufficient to overturn what others decided, notably Peters and Bond, known lumpers. The morphology looks pretty distinctive, especially the bill color. It certainly looks very thick-billed in the photos of the specimens and the one “moth-eaten” specimen that Garrido has at his house in Havana. 

I spent a fair amount of time trying to find information about the little known taxon from Cuba. Few of the Cuban ornithologists have claimed to have seen it. How can it have the population that is conjectured? We hear it declined because of farmers shooting them, but most farmers don’t have shotguns, especially in recent decades. They say it preferred woodlands, where farmers aren’t. Because it is treated as a subspecies it isn’t covered in Threatened Birds of the Americas. I gather there are few extant specimens. Are any of these from the last century? I’m just asking. The one photo (in this motion) by the experienced naturalist, Nils Navarro, of a recently seen bird, looks ambiguous to me. What I can see doesn’t look right in terms of the bill color and structure. Has the bird ever been photographed well? I’m left thinking of the case of Zapata Rail (Cyanolimnas cerverai) where proven records now date back to 90 years.

YES. I vote “yes” with much reluctance, and could easily be swayed to “no” pending the comments of others. As noted in the proposal, there’s not much to go on, and so I find Oscar’s rationale slightly more convincing than an opposing view. This is a truly arbitrary decision. One thing is for sure: that anyone could interpret a slight difference in % sequence divergence at two mitochondrial loci between an allopatric, insular taxon and its continental sister as evidence for or against species rank is special pleading. Regardless of outcome, that Oscar has assembled all the evidence in one spot is productive.

YES. I vote for this treatment, especially given how invariable uncinatus (polymorphy, sex and age variation aside) is throughout its vast range, the morphological differences (plumage and proportions) seem as marked as in many species of raptor, or more so. The mtDNA data are not inconsistent with, and provide further weak support for, species status. I cannot see why this should continue to be treated as a subspecies when e.g. Ridgway’s Hawk is given full species status.

YES. This is clearly a borderline case, and I could see it going either way. Further, the morphological data are based on very small sample sizes (n = 2 for wilsonii). However, as pointed out in the proposal, wilsonii seems to be an outlier phenotypically (bill color, plumage pattern) compared to other populations. That, combined with the available genetic data (even if only mtDNA), lean me toward a yes vote. 

YES. I voted to accept this split in 2007 and continue to believe this is the best course. The degree of genetic differentiation and rather noticeable difference in bill and face skin color convince me that the Cuban population would be reproductively isolated from the widespread unicinatus, especially considering that such “minor” differences in many accipitrines can be reproductively isolating.  

YES. As others have mentioned, it’s a borderline case, but I vote for two species in this case. Although there is only mtDNA, I think the degree of genetic difference seen between wilsonii and the other populations, compared to how little genetic structure/difference there is among populations of uncinatus points in the direction of species status. The morphological differences described and illustrated in the proposal are also consistent with multiple species.

YES. Very well written proposal. A borderline case as others have mentioned. The phenotypic differences do seem pronounced and differentiation of the Cuban wilsonii seems pronounced relative to what is observed across a very large geographic expanse among the other subspecies. Although mtDNA is all that we have for genetic data, I am comfortable elevating wilsonii to species level within an integrative framework.

YES. The DNA evidence is weak but clear, not a lot of sequence but there are differences between wilsonii vs uncinatus. The pattern of the color is clearly different between them.

YES. It is not an easy decision given the available data. However, as mentioned in the proposal and previous comments, the morphological differences between wilsonii and uncinatus are evident, mainly when compared to the low geographic variation in the widespread continental uncinatus. The mitochondrial data, even when weak, adds support to the distinction of wilsonii.

YES. This is a marginal case, but given that the moderate morphological distinctiveness and moderate genetic distinctiveness of the Cuban Kite, versus essentially no morphological variation in the widespread continental Hook-billed Kites, I think splitting the Cuban Kite makes sense.

NO. I went back and forth on this a lot, and am still not settled on a firm choice, but, given that uncinatus does seem to be rather variable in terms of plumage and morphology, wilsonii is not necessarily always very distinctive (although that being said, the lack of variability within wilsonii, together with apparent genetic divergence does suggest a fair degree of isolation and perhaps species-level diversification).

NO. I was a “no” on this in 2007, being unswayed by the genetic data but recognizing that the case should be further investigated. This taxon seems to be in that gray area between subspecies and species, and making that decision in this case is like reading tea leaves – we’re left grasping at small things. It is at least a good subspecies, but do the differences add up to full species? I lean toward following Amadon’s expertise with the complex on this. In considering things more broadly, on the one hand, while many deride the Tobias et al. criteria, the passage of time and accumulation of case studies indicate that their use has proven much more often right than wrong (Tobias et al. 2021; however, here I am uncomfortable using a yardstick developed in very different taxa, preferring subject experts like Amadon). On the other hand, across Aves we are likely oversplitting allopatric taxa at the species level (see Hudson & Price 2014). Excellent proposal.

Hudson, E. J., and T. D. Price. 2014. Pervasive reinforcement and the role of sexual selection in biological speciation. Journal of Heredity 105:821-833.

Tobias, J. A., P. F. Donald, R. W. Martin, S. H. M. Butchart, and N. J. Collar. 2021. Performance of a points-based scoring system for assessing species limits in birds. Ornithology 138: ukab016

2022-B-5: Treat Accipiter chionogaster (White-breasted Hawk) as a separate species from A. striatus (Sharp-shinned Hawk)

NO. I have seen this taxon at El Triumpho, Chiapas, Mexico. It certainly appeared striking with the starkly white underparts. I think the evidence is ambiguous and could, I guess, go either way. But, I’m left wondering about the taxa from the Greater Antilles. Further, although Ferguson-Lees and Christie (2001) do outline the separate groups, they don’t split them as separate species. They add that the subspecies venator is similar to South American erythronemius in many ways. Not surprisingly, given the isolation, the West Indian taxa are genetically more distinct than chionogaster. The West Indian taxa all seem to be rare which makes them harder to study.

I’m left wondering about the vocalizations and how they might differ. In terms of the number of years that I have looked at birds, I finally actually heard a Sharp-shinned Hawk call (in Idaho in August 2021), it no doubt being on the breeding grounds. It was the rather high pitched yelping “kew-kew-kew,” utterly and completely different from a Cooper’s Hawk. I would add that Gundlach’s Hawk (Accipiter gundlachi), an endemic “species” from Cuba, sounds and looks very similar to a Cooper’s Hawk. In fact, from limited experience, Gundlach’s has responded better to recordings from Cooper’s than Gundlach’s. If North American Sharp-shinned Hawks are any indication of the difficulty in recording calls, one can only imagine getting good recordings of other taxa, especially those rare and perhaps hard to reach taxa from the Greater Antilles. 

Anyway, I would prefer a quantitative analysis of the species as a whole, particularly factoring in the West Indian taxa.

NO. This is another very tricky scenario, and I do think chionogaster, along with the South American and Caribbean taxa, are likely good biological species, however I don’t think there is enough information to change the status quo at the moment. In particular, I’d like to see a population-level phylogeographic study of genetic diversity that includes individuals from the Mexican subspecies as well as individuals from Arizona and New Mexico to assess the possibility of gene flow among these groups. However, the differences in breeding time, along with potential differences in courtship displays, do hint at barriers to reproduction between chionogaster and the North American populations.

NO. This is another basically arbitrary decision, and as noted in the proposal, there is no convincing evidence one way or another on species rank, and not enough to change the status quo, in my opinion. A benefit of keeping them as conspecific is that would encourage further research, especially on voice and display. In the Eastern Hemisphere, several Accipiter species show strong, discrete geographic variation comparable to that in A. striatus in terms of variation in ventral color and pattern: A. tousenelii, A. hiogaster (aka Variable Goshawk), A. fasciatus, A. albogularis, A. virgatus, A. erythrauchen. Check out the plates in HBW. I suggest that all these complexes be considered the same way, i.e. highly polytypic species, until we find an objective and sensible way to assign species rank. By the way, Neotropical A. bicolor also has at least three subspecies that differ among themselves as much as do the A. striatus groups. I am agnostic on whether these complexes represent multiple species because there are no data to assess this. I do recommend sticking to the status quo until convincing rationale overturns it, as recommended by Shawn in the proposal.

NO. Despite the striking plumage differences, the Catanach et al. study seems to show chionogaster being very close to velox and ventralis, while erythronemius and the three Caribbean taxa are much more distinct. I feel sure there are multiple species in the complex, and that chionogaster might turn out to be one of those, but the evidence is somewhat contradictory. If anything the Caribbean striatus group and erythronemius are stronger candidates for splits.

NO. I think we don’t know enough about this complex to make this split. There might be a split or splits to be made, but I don’t think we have sufficient evidence for this.

NO. I agree that the best treatment for now is to continue to recognize A. striatus chionogaster.

NO. As noted in the proposal, I think that more data (genetic, quantitative analyses of phenotype, voice) are needed across the entire complex prior to making a definitive decision on splitting.

NO. I’d like to see how this situation compares to other closely related accipiter taxa with polymorphic or variable populations. It would be nice if we could include the West Indian taxa at the same time. 

NO. A comprehensive phylogeographic study is needed before an assessment of this split can be made. Would be better to stick with the status quo for now.

NO. There is not enough evidence to support the separation; the differences in color could be explained by a biogeographic cline.

NO. I agree with the recommendation in the proposal, chionogaster might represent a separate species from striatus, but a phylogeographic study with thorough geographic sampling is required before taking taxonomical decisions.

2022-B-6a: Reconsider treatment of Barn Owl subspecies Tyto alba insularis and T. a. nigrescens: Recognize T. insularis as a species with subspecies insularis and nigrescens

YES. Given the morphological (size and osteology) differences elucidated by Suarez and Olson, who have worked very extensively on this complex both fossil and modern, I’d prefer to trust their judgment on this issue rather than invent another solution, so I’m voting to treat insularis and nigrescens as a separate species. I can’t think of other examples where notable osteological (not just size) differentiation (except e.g. salt gland in marine vs. freshwater populations) occurs intraspecifically (though there may be examples), so I think this is especially compelling. Plus, we are talking about different parts of the Caribbean that typically have different avian species, not a single homogenous island group. (Furthermore, we really do need to get a proposal in so we can finally take the step of splitting Old vs. New World Tyto alba, something that is pretty clearly warranted.)

YES. A borderline case for sure. But in my opinion, the plumage and osteological differences are enough to move them to separate species, especially since we also seem to be willing to merge “T. cavatica” from Puerto Rico with “T. glaucops” from Hispaniola based solely on osteology. I agree we would want full genetic and vocal analyses of all barn owls, but how long would we need to wait for that?

NO. I don’t support recognizing subspecies insularis and nigrescens as separate species.

NO. I don’t support species status for Tyto insularis.

NO. A tough one, and I could be swayed to a “yes” by comments from others. At this point, I favor the conservative approach, and I dislike making changes in species limits in nocturnal birds without a comprehensive analysis of vocalizations, and fiddling with this case is premature before the overall complexities in the Tyto alba complex are resolved.

NO. Right now I think there is insufficient evidence to consider insularis a distinct species, or really any new treatment for these taxa.

NO. I voted in support of splitting Tyto alba into three species, but I think it’s premature data-wise to be making more species-level splits. The osteological evidence of distinctness between glaucops and insularis/nigrescens and the comparison with sympatry in glaucops and mainland alba suggests that species-level splits might well be warranted; but I am not finding a compelling case that insularis/nigrescens is not a major subspecific group of glaucops., as HBW treats it. Size differences in insular forms are so well known from within-species examples that I don’t have much confidence in using these as criteria for species limits.

NO. I prefer the conservative approach of maintaining these as subspecies for now.

NO. I think a vocal and genetic analyses are needed before making this split.

NO. While a comprehensive analysis of Tyto alba is certainly daunting, I prefer the conservative approach for the time being.

NO. Retain insularis and nigrescens as subspecies of Tyto alba. There is a lack of data.

NO. It is premature to split T. insularis when there are so many unknowns in Tyto systematics.

2022-B-6b: Reconsider treatment of Barn Owl subspecies Tyto alba insularis and T. a. nigrescens: Treat insularis and nigrescens as subspecies of T. glaucops rather than T. alba

YES. I vote for reconsidering the two taxa from the Lesser Antilles and placing them into T. glaucops.

The sympatric occurrence of two types of Barn Owls on Hispaniola necessitated the split of T. glaucops as a separate species. The latter seems to prefer more wooded, less open, areas. Given the osteological evidence detailed by Suarez and Olson (2020) the best place to put them now is in with T. glaucops. And, since it was apparently also in Puerto Rico, why not Dominica, St. Vincent, the Grenadines, and Grenada? The action to split Ashy-faced Owl necessitates making the best possible decision regarding insularis and nigrescens and I believe that Suarez and Olson (2020) have given the best place to put it. 

I do agree that an overall and comprehensive treatment needs to be done. I’ve mentioned this before when we previously considered Barn Owls, but Robb (2015) gives compelling arguments that the first split that needs to be done is American Barn Owl (T. furcata). I quote: “By contrast [western Palearctic taxa], there are dramatic differences between Common and American Barn Owls. American has much shorter perennial screeches, typically less than a second long, and in a wide range of recordings, I have never heard American giving anything remotely like a courtship screech. Gerrit Vyn is the author of an excellent CD on North American owls (2006). When I sent him an example of Common Barn Owl courtship screeches, he confirmed he knew nothing similar from American. This not only supports separating the two species but also the two kinds of screeches.” 

Continuing (ibid) “At the same time, American Barn Owl has a prominent flight call that is completely absent in Common Barn owl. It was Gerrit who recorded the metallic clicking sound in CD1-06, which he calls the ‘kleak-kleak call’ (Vyn 2006). Unpaired males use it most often (Gerrit Vyn pers. comm), so it must have an important role in mate attraction. Marti et al. (2005) reported that males kleak in the vicinity of the nest, soon after leaving the daytime roost, and when approaching with food deliveries. Several other Tyto species have similar calls (e.g. African Grass Owl T. capensis, Eastern Grass Owl T. longimembris and Australian Masked Owl T. novaehollandiae). So rather than being an American invention, it seems that Common stopped using this call and replaced it with courtship screeching.” They include spectrograms and recordings. 

I looked up the vocalizations in Ashy-faced Owl in Raffaele et al. (1998) and they say: “hissing cry, prefaced by a series of high-pitched ratchety clicks. Konig et al. (1999) say “several rapid trills of clicking sounds are followed by a rasping wheeze of about 203 seconds duration which may represent song. According to recordings, the vocalizations of Ashy-faced Owl differ from those of Barn Owl.” They say nothing about geographic variation in Barn Owl vocalizations, and since I believe the authors from the Old World, perhaps they are reflecting their bias of vocalizations from the Old World. Thus Ashy-faced would sound different, but the description of Ashy-faced doesn’t sound that different from American Barn Owls. I’m left wondering if the differences between New and Old World Barn owls are more dramatic than the taxa we are considering splitting. 

Selective literature cited:

Konig, C., F. Weick and J.-H. Becking. 1999, Owls, A Guide to the Owls of the World. Yale University Press. 

Raffaele, H., J. Wiley, O.Garrido, A. Keith and J. Raffaele. 1998. A Guide to the Birds of the West Indies. Princeton University Press. 

Robb, M. & The Sound Approach. 2015. Undiscovered Owls, A Sound Approach guide. Published by The Sound Approach. 

Vyn, G. 2006. Voices of North American owls. 2006. 2 CD’s and booklet. Ithaca. 

YES. While I think it is premature to elevate insularis to species status, I think the evidence to retain it as part of alba very weak, and that it shares more similarities to glaucops, so I would favor including insularis and nigrescens as subspecies of T. glaucops.

YES. I could live with this option but don’t think it is the best one. However, if 6a fails, I vote “yes” to consider insularis and nigrescens as subspecies of glaucops.

YES. I am ambivalent on this. I think close association with glaucops seems likely, and the skeleton information suggests this, too, leaving some doubt whether the differences rise to species level. I could agree to follow HBW on this. So I’d lean toward treating insularis and nigrescens as subspecies of glaucops, but not strongly.

NO. I agree with the proposal recommendation.

NO. I am inclined to leave this alone in the absence of compelling evidence to associate insularis and nigrescens with glaucops.

NO. I don’t see any compelling evidence to move subspecies insularis and nigrescens to T. glaucops at this time.

NO. Vocal and genetic analyses are needed before moving these taxa to glaucops.

NO. I vote for retaining the status quo and keeping these taxa as subspecies of alba.

NO. I don’t think there is enough evidence at present to overturn the status quo. I would prefer to leave insularis and glaucops as subspecies of T. alba at this time.

NO. Retain insularis and nigrescens as subspecies of Tyto alba. There is a lack of data.

NO. Treat insularis and nigrescens as subspecies of Tyto alba until further data are available.

2022-B-6c: Revise the distribution statement of T. glaucops

YES. 11 without comment.

YES. Given Suarez and Olson (2020), I favor placing the extirpated Puerto Rico (“T. cavatica”) birds with T. glaucops as well as nigrescens and insularis (Suarez and Olson 2020). There will be other taxa to sort as well in the future as listed in this well-crafted motion. 

2022-B-7: Merge Ciccaba into Strix

YES. The molecular data clearly show that Ciccaba is nested within Strix, thus mandating this change. 

YES. There is strong genetic evidence.

YES. The data seem clear.

YES. The phylogeny provides support for merging Ciccaba into Strix.

YES. The genetic data show that Ciccaba is embedded within Strix, so some change is necessary, and merging Ciccaba into Strix is the best option.

YES. This was done a few decades ago by Konig et al. (1999). 

YES.  Existing published data require this treatment, at least until a complete phylogeny of Strix. 

YES. This produces a rather heterogeneous Strix but required by placement of virgata within Strix. A more complete phylogeny would be helpful to see if parts of the Strix clade could be parceled off as separate genera.

YES. Given the paraphyly revealed by Salter et al. (2020), some taxonomic change needs to occur, and lumping Ciccaba into Strix seems the most prudent and simple solution. 

2022-B-8a: Treat Saltator coerulescens (Grayish Saltator) as three species: Split grandis s.l. (incl. olivascens) from coerulescens

YES. Two without comment.

YES. I vote for three species based on the combined genetic and vocal information that indicates a deep split, and the mtDNA analysis suggesting paraphyly with striaticollis, though confirmation is desirable. Even if they aren’t paraphyletic, the genetic and vocal divergence seems to indicate that three species are involved.

YES. The deep paraphyly between Middle American + Caribbean vs Amazonian lineages suggest these are very divergent lineages. Although this is just based on mtDNA and should be interpreted with caution, I highly doubt this result would change with more loci sampled. Vocal divergence confirms these are likely different species.

YES. The combined genetic, song, and plumage differences are enough to convince me that these three taxa should be considered separate species. I appreciate that this is only mtDNA data and further detailed analyses of olivascens and grandis are needed; however, enough data are present for me to be comfortable with a three way split at this time. I also prefer that we conform to SACC on this one. The English names presented are fine.

YES. I vote yes to three species, but yes to two species too, following the split supported by SACC. We normally follow along with their decisions. I’m puzzled that the motion says two species are involved in the NACC area, while it seems that only one is involved (S. grandis). Yes to the proposed English names too.

YES. This is a borderline decision, I am also inclined to vote NO. Following an integrative approach (geography, voice, mtDNA, plumage coloration), I vote for splitting S. grandis and S. coerulescens. I agree with Oscar Johnson’s comments in the SACC proposal, and mtDNA does a good job clustering populations. However, I recognize that the phylogeny in the proposal is based solely in mtDNA and some nodes are not well-supported. Further studies using genomic data and extensive geographic sampling (including contact zones) are needed.

YES. I think we should follow the SACC for what is an essentially South American problem. However, the single locus genetic results and lack of innate song, and haphazard sampling are problematic. In addition, Saltator coerulescens (s.l.) is a species of early successional habitats, common in brush around clearings.  With rapid deforestation in many areas, its range is expanding.  Situations of apparent parapatry may be extremely recent, and not have had enough time to show gene flow or break down of vocal differences.  I like the SACC English names if the proposal passes.

YES. This is a decision I went back and forth on, but I think the combination of genetic data showing paraphyly (even though it is only a single locus) and the vocal evidence of a very sharp boundary between the Amazonian and Caribbean clades is enough to say that they are separate species. Although more data from that transition zone would be really interesting to see, with more in depth analysis of the vocal, morphological, and genetic transition from one group to the other. 

NO. We’re proposing to split an oscine passerine based on single-locus genetics and voice. I am not comfortable with that, especially using mtDNA alone to infer species limits. Moreover, there are serious sampling and node strength issues with the mtDNA data leading to important questions about species limits being unanswered. I think the data are very interesting and that further work might very well indicate there are species limits here, but I think it would be premature to split them based on these data alone. On English names if we do approve the split: Fine.

NO. There may indeed be multiple species, but I don’t think the data are sufficient to make a split at this time. In addition to being based on mtDNA plus a non-quantitative analysis of vocal differences, some nodes are poorly supported and the sampling is incomplete – as far as I can tell, not all subspecies were studied and there are no samples from putative contact zones. I think it’s best to retain the present treatment pending more study.

NO. I recommend waiting for more study.

2022-B-8b: Treat Saltator coerulescens (Grayish Saltator) as three species: Split grandis from olivascens

YES. Two without comment.

YES. I vote for three species based on the combined genetic and vocal information that indicates a deep split, and the mtDNA analysis suggesting paraphyly with striaticollis, though confirmation is desirable. Even if they aren’t paraphyletic, the genetic and vocal divergence seems to indicate that three species are involved.

YES. I had originally voted “no” but am changing my vote to align with the SACC decision as this involves a largely SACC-distributed taxon in olivascens. I do have some reservations: while I am comfortable splitting the Middle America + Caribbean vs Amazonian lineages, I think this additional split is premature. Additional geographic sampling, multilocus phylogenetic and demographic analyses, and integrative taxonomy (phenotypes) would be preferable in my opinion, but I also think it is important to have a unified taxonomy and will defer to SACC on this proposal. 

YES. The combined genetic, song, and plumage differences are enough to convince me that these three taxa should be considered separate species. I appreciate that this is only mtDNA data and further detailed analyses of olivascens and grandis are needed; however, enough data are present for me to be comfortable with a three way split at this time. I also prefer we conform to SACC on this one. English names presented are fine.

YES. This is a borderline decision similar to 2022-B-8a. I vote for splitting S. grandis and S. olivascens given that vocal differences and time since divergence are comparable to other species pairs in the genus Saltator. However, further behavior, voice, and genetic studies need to be conducted in the contact zones in South America.

YES. I think we should follow the SACC for what is an essentially South American problem. However, the single locus genetic results and lack of innate song, and haphazard sampling are problematic. In addition,  Saltator coerulescens (s.l.) is a species of early successional habitats, common in brush around clearings.  With rapid deforestation in many areas, its range is expanding.  Situations of apparent parapatry may be extremely recent, and not have had enough time to show gene flow or break down of vocal differences.  I like the SACC English names if the proposal passes

YES. I vote “yes” to three species, but “yes” to two species too, following the split supported by SACC. We normally follow along with their decisions. I’m puzzled that the motion says two species are involved in the NACC area, while it seems that only one is involved (S. grandis). Yes to the proposed English names too. 

NO. I recommend waiting for more study.

NO. We’re proposing to split an oscine passerine based on single-locus genetics and voice. I am not comfortable with that, especially using mtDNA alone to infer species limits. Moreover, there are serious sampling and node strength issues with the mtDNA data leading to important questions about species limits being unanswered. I think the data are very interesting and that further work might very well indicate there are species limits here, but I think it would be premature to split them based on these data alone. On English names if we do approve the split: Fine.

NO. There may indeed be multiple species, but I don’t think the data are sufficient to make a split at this time. In addition to being based on mtDNA plus a non-quantitative analysis of vocal differences, some nodes are poorly supported and the sampling is incomplete – as far as I can tell, not all subspecies were studied and there are no samples from putative contact zones. I think it’s best to retain the present treatment pending more study.

NO. While I think there is enough evidence to split the Amazonian taxa from the Caribbean and Central American groups, I do not think there is currently enough evidence to split the Central American and Caribbean groups yet. 

2022-B-9: Recognize Haematopus bachmani (Black Oystercatcher) as a subspecies of H. ater (Blackish Oystercatcher)

NO. Although further study might well bolster the case that bachmani is best treated as subspecifically distinct within ater, I don’t think the evidence is yet strong enough to make such a major change. First, it’s an odd distribution of a species of the rocky marine littoral, with a large gap in seemingly suitable areas. The fact that both ater and bachmani hybridize with palliatus to an uncertain but apparently significant degree may or may not indicate that they would hybridize with each other to an even greater degree should they meet. The mtDNA phylogeny in Senfeld et al. suggests they are closely related, but paraphyletic with palliatus, and many of the Old World oystercatchers long recognized as species also seem to be very closely related on the same evidence. Murphy’s observations on differences in chick plumage between bachmani and ater provide evidence on species limits seemingly overlooked by HBW/BLI in making their assessment, although it probably would not have made the difference in their scoring system. In the absence of a vocal analysis, and with so many other unknowns, I think it’s better to hold off for now until more complete evidence on oystercatcher relationships is available.

NO. I appreciate the comments from members of SACC who know a great deal about these birds and have added more about vocalizations and morphology and agree that more work with the whole group will be fruitful. While given present evidence they probably should have been lumped historically, there are enough clues among the information provided by SACC members to suggest that future work will support the continued split. Better data will make a decision much easier in the future.

NO. More research is needed before taking taxonomical decisions.

NO. As noted by others, more study is needed.

NO. This is a fascinating system, and I would love to see more study into oystercatchers not just in North and South America, but globally. While intriguing, the low genetic divergence between ater, bachmani, and palliatus does not seem to be any different from many of the Old World species. The repeated pattern of pied and black oystercatchers around the world is an area ripe for study.

NO. Perhaps Jehl’s paper can be attached. I am particularly interested in the degree of hybridization between American Oystercatcher (Haematopus palliatus) and Blackish Oystercatcher (H. ater). I see no mention of such hybridization in the Hayman et al. (1986) thorough shorebird guide, or by Jaramillo (2003) in his Chile guide. Hayman et al. (1986) do mention hybridization between American and Magellanic Oystercatcher (H. leucopodus). Separation of Blackish and American seems to be largely dictated by habitat (rocky shorelines for the former, sandy beaches or muddy estuaries for the latter). Breeding season habitat seems to largely separate Magellanic too (Jaramillo 2003). Perhaps the bill shape is important in species recognition for Blackish Oystercatcher. Jaramillo says Blackish Oystercatcher has a louder and lower pitched display vocalization than American which to my ear sounds identical to American. A more pertinent question is whether to lump American and Black (H. bachmani). The two interbreed across a wide latitudinal zone in northwestern Baja California with hybrids being recorded into coastal southern CA and casually farther north (e.g. Monterey area). Indeed, the subspecies frazari could be considered just a hybrid population. Jehl had a scoring system and seemingly randomly assigned numerical levels where a bird could be considered an acceptable Black, or an American. The only truly pure American Oystercatchers for California might be the three that made it to the Salton Sea (no doubt from the Gulf of California) back in the summer of 1977. Hayman et al. (1986) mention that frazari inhabit rocky coastlines, no doubt facilitating hybridization with Black Oystercatchers in the broad zone of overlap. 

NO. More studies needed.

NO. I think such a change requires more solid data on several fronts, particularly on species limits within all NW oystercatchers (ater, bachmani, leucopodia, and palliatus) and how these limits are shaped by vocalizations, pied vs. all-black plumage, and bill shape and size. 

NO.  More detailed studies required.

NO. More research is needed to overturn the current status.

NO. Be sure to see comments on the SACC version for a thorough dismantling of the rationale in the proposal: https://www.museum.lsu.edu/~Remsen/SACCprop931.htm

2022-B-10: Treat Caribbean Island populations of Troglodytes aedon (House Wren) as seven species: (a) Recognize T. beani, (b) Recognize T. guadeloupensis, (c) Recognize T. rufescens, (d) Recognize T. martinicensis, (e) Recognize T. mesoleucus, (f) Recognize T. musicus, and (g) Recognize T. grenadensis

YES to all. As the very person who convinced NACC back in the mid-1980s to adopt a policy of not making changes unless there were new published data, I feel somewhat hypocritical on this one, and I understand the views of the NO voters on this based on that policy. I’m not sure if it is a rule or just a guideline, but it’s a good one … in almost all cases. I don’t think this is one of those. The actual “data” for the lump comes from a single sentence in Hellmayr nearly 90 years ago. There are no data to justify this treatment, and I regard this lump as the “type specimen” of the overzealous application of the BSC and perhaps the worst decision of the Lumperama Era. All the data one needs to see showing that these should never have been lumped are actually published in terms of voice and habitat; the only thing that is missing is a synopsis of them.

YES to all. Considering Trogolodytes pacificus and T. hyemalis are reproductively isolated but have far fewer differences in song and morphology (and habitat to an extent) than between any of the Caribbean taxa of aedon, and that the original lump was based on a near lack of analysis, I think we should waive the required published requirement in this case. It would be nice to have all the genetics and playback experiments, but I would still strongly base my taxonomic decision on morphology and vocalizations for these allopatric taxa.

YES to all. Enough evidence in morphological and vocal differences to separate as species, especially given the lack of evidence to lump them in the first place. I appreciate the concern of other members of having a synopsis of the situation in a peer-reviewed journal. Perhaps the authors can use their proposal to jump start such a publication.

YES on (a-f), NO on (g). (a-f) Trogolodytes beani is the only one I’ve seen and heard. Little suggested to me that this should be considered a House Wren. Most of the others from the Lesser Antilles look totally unlike a House Wren and I’m inclined to support the motion, though appreciate the notes of caution expressed by others. When no rationale is given for the massive lump, it’s hard to feel much about deference to that decision. If some other course is adopted as to how to proceed on this entire issue, I’m open to that too. (g) The authors of the motion are neutral on this, so leave it at that. Add a species like Hook-billed Kite for species that share affinities with the mainland. 

(a) YES. The song is very distinctive, and the morphology is moderately so (presumably convergently similar to e.g. mesoleucus). (b) YES, although little known the specimens show distinctive morphology, the single sonogram indicates a distinctive song, and it seems to have been a rainforest species (see 10c). (c) NO, because it looks like it could well be a subspecies of T. guadeloupensis (which has priority), from an adjacent island and seemingly differing only in minor ways. But if it was a choice between keeping it as a race of aedon and treating it as a full species, I would choose the latter, as rufescens is very different from aedon in morphology and song, and a rainforest species. (d) YES, although we know nothing of the song it appears to have been morphologically distinctive and to have been a rainforest form, and to most closely resemble the Grenada form from which it is separated by the quite different St. Lucia population. (e)  YES, it is morphologically distinctive and a dry-forest specialist, though its song is similar to aedon so this is a less persuasive case. (f) YES, it is moderately distinctive morphologically with a highly distinctive song, though ecologically it is similar to aedon. (g) NO, although many photos show very dark birds there are others that look more ordinary, and with the aedon-like song and habitat plus the fact that Grenada has more continental species than Lesser Antilles further north, treating it as conspecific in the absence of e.g. genetic evidence to the contrary makes sense to me.

NO to all. I recommend waiting for an integrative study with morphology, molecular and song.

NO to all. I feel our policy has been to wait for peer-reviewed publication and that to waive that periodically for a chosen in-group would be a major procedural error. No disrespect to the proposal authors and the strong proposal they have submitted. Publish it, please. I look forward to reading that version; I am sure there are good species here. (P.S. There are no House Wrens in Alaska.)

NO to all. This is an excellent review, I understand the rationale for going back to the treatment of Ridgway, and there probably are multiple species. However, I too would like to see published and ideally quantitative data (voice, morphology, and genetics-sampling from toe pads?) before making this large-scale split.

NO to all. The variation in these wrens is remarkable and the proposal presents that variation in morphology and voice. However, I agree that published quantitative data (voice, phenotype) should be available before the split, including genetic data from the islands and the continent.

NO to all. I am very conflicted in this vote, as I truly believe that these island taxa represent diagnostic species, and the proposal lays out the available evidence in a very clear and compelling way. However, as others have pointed out, our policy to wait for peer-reviewed publications is fundamentally important to our process. 

NO to all. I’m sure that there are good species within this complex and the proposal is a nice synthesis, but I don’t think we should deviate from our expectation of requiring peer-reviewed publications to make our decisions.

2022-B-11: Treat Piaya mexicana as a separate species from P. cayana (Squirrel Cuckoo)

NO. It could well be a separate species, especially if it really is essentially parapatric with just a narrow hybrid zone, but the evidence is contradictory and it seems plausible that it may not be the only split needed (e.g. macroura). Another case where a good integrative study of the species (complex) may provide the needed guidance.

NO. There is a lack of published studies on the group.

NO. I agree that this situation warrants further work to determine species limits under the BSC. Under a PSC/ESC, I, too, would treat them as different, but under the BSC that’s why we have subspecies. That zone of contact is really intriguing.

NO. Based on the lack of data and need of phylogeographic research on Piaya cayana. I highly appreciated the specimen photos included in the proposal.

NO. I agree with the proposal that more data are needed, including study of putative introgression across the contact zone. These are best treated as subspecies for now. 

NO. I agree with others that there needs to be more research done on this group. It is intriguing that it may be parapatric with a very narrow transition between cayana and mexicana, but more study is needed to confirm this. 

NO. I agree with others about more studies needed. The morphological similarity of pallescens from dry eastern Brazil to west Mexican mexicana is interesting. I see nothing compelling to make the split at this time. 

NO. Cuckoos rely so strongly on vocalizations, I would expect differences here if mexicana and thermophilus were reproductively isolated. The plumage differences are striking (along with the tail length), but the proposal shows that these similar differences may have arisen in other subspecies of cayana in dry environments. 

NO. I agree that more detailed integrative taxonomic studies are needed to recognize mexicana and cayana as separate species under the BSC.

NO. As outlined in the proposal, there are insufficient data for a change in species limits. The plumage differences of mexicana basically follow Gloger’s Rule, as does the variation in South America (e.g. pallescens). Ideal would be a study that analyzes the considerable plumage variation in the South American taxa, including a characterization of what’s going on in the contact zones. To treat mexicana as a species without addressing the rest of the taxa is somewhat unsatisfactory, but I would do it if a thorough analysis of the contact regions between mexicana and thermophila were available and the analysis showed that those intermediate birds were outnumbered by pure parentals, which would indicate barriers to gene flow. Or a thorough study of vocalizations, including playback trials. I also note, once again, that a rejected proposal is a positive outcome in that it outlines what data are needed and in the potential encouragement of additional research.

NO. Further research needed. As the proposal argues, the plumage differences used as a basis for a PSC split potentially intergrade and might also be adaptive to different environments. 

2022-B-12: Treat Patagioenas albilinea as a species separate from P. fasciata (Band-tailed Pigeon)

NO. Although they look and sound so different in North and South America, the subspecies crissalis seems to be intermediate in both morphology and song over a wide area. More in-depth analyses of vocalizations and DNA would be needed to come to any other conclusion.

NO. I agree with the proposal that more work is needed before adopting a treatment of separate species – specifically a quantitative assessment of phenotypic, vocal, and genomic differences among populations across the entire range, with special attention paid to areas where traits appear to be intermediate.

NO. I agree with the recommendation of the proposal and with previous comments. Thorough geographic sampling and quantitative data on phenotype, voice, and genomic differences among populations are needed before making any decision. In addition to the intermediate subspecies from Costa Rica and Panama (crissalis), the variable subspecies from Honduras and El Salvador (letonai) and Nicaragua (parva) should also get special attention, since the photographs of specimens in the proposal clearly show the extensive variation of plumage color in letonai.

NO. The differences between the major subspecific groups P. fasciata and P. albilinea and the variation within them shown in the specimen photos fit well within our concept of subspecies within a biological species, and the intermediacy of P. f. crissalis adds considerable weight to favoring our continuing that treatment. New work on this group will prove interesting.

NO. I agree with the recommendation of the proposal to continue treating these groups as a single species. While I do think the northern fasciata and southern albilinea groups could very well represent distinct species, the subspecies crissalis definitely adds confusion to the system, and more work is needed to clarify the status of this seemingly intermediate subspecies with respect to the other taxa. As others have stated, I’d especially like to see a detailed phylogeographic study as well as additional detailed sampling of vocalizations from across its range. 

NO. Not enough evidence to split. As noted in the proposal and by earlier authors, Costa Rica birds are intermediate. Genetic analysis might help clarify the degree of gene flow across this wide-ranging species. 

NO. There is not enough evidence to split. I agree with the recommendation of the proposal, genetic data, color and morphometric analysis are needed.

NO. Calls are especially important in species recognition in columbids, so I appreciate the in-depth analyses of vocalizations in this proposal. Although the geographically intermediate taxon (crissalis in Costa Rica and Panama) mostly shows the song pattern of the southern albilinea, the small sample of this taxon (n=7) also has cuts that show calls unaligned with either taxon, or some notes more closely aligned with the northern fasciata (s.s.). P. f. crissalis shows some morphological intermediacy as well.  I think we should wait for expanded analysis of vocalizations before splitting.

NO. Morphologically, I would say this looks like a cline, albeit messy, with intermediate and variable populations in the intermediate geographic region of Middle America. Calls should be an important component of making a species-level decision in doves. Again crissalis from southern Middle America is a problem for the two species treatment. It may not quite be intermediate, but doesn’t fall cleanly into the albilinea group. I would also note that two widespread congeners, P. plumbea and P. subvinacea, have fairly substantial geographic variation in voice. Perhaps all should be split, but I don’t think the case has been made for that.

NO. As others have said, a more in-depth analysis including genetic samples and an integrative phenotypic data set is needed in my opinion. 

NO. For the reasons detailed by others. More studies are needed from Middle America as well as overall vocalization studies. The Band-tailed Pigeons I know here in the U.S. have distinctive display flights (rapid shallow fluttery flight). I wonder if this is consistent throughout the range. North American birds, and perhaps others (?) are highly migratory. Phil Unitt recently came across a specimen of Band-tailed Pigeon (monilis/fasciata) near the range of vioscae from the Sierra de San Lazaro in southern Baja California. The later subspecies lacks a tail band, so recognition is not difficult. I can well see events of colonization in the not too distant past. 

NO. As documented in the proposal, this one requires a formal, comprehensive analysis.