Recognize newly described Bubo jalca

Proposal (1090) to South American Classification Committee

Recognize newly described Bubo jalca

Background: SACC Proposal 1052 resulted in the split of Bubo virginianus into four species (B. virginianus, now restricted to North America, B. nigrescens in the northern Andes, B. magellanicus in the southern Andes and Patagonia, and B. nacurutu in lowland South America). This was the second proposal to SACC regarding the taxonomy of the B. virginianus complex, the first (Prop 328) having been rejected due to conflicting and confounding information, most importantly, recordings made in Piura, Peru, by Ted Parker of a population where a specimen identified it as B. (v.) nigrescens, but vocalizations suggested affinities with the otherwise vocally distinct B (v.) magellanicus. In Prop 1052, I reviewed more recent publications and also recordings available on on-line archives and concluded that the vocalizations in the Parker recordings represented vocalizations found throughout the range of B. (v.) nigrescens, providing justification for SACC to accept the split of the complex. One of the publications that I reviewed in the writing of Prop 1052 was Lopez-Lanus (2015), in which the author suggested that the Piura birds were an undescribed taxon due to vocal characters. Lopez-Lanus and coauthors have now followed up on that taxonomic premise and have published a newly-named taxon.

New information: Lopez-Lanus et al (2026) have published a description of Bubo jalca based on the Piura, Peru, recordings by Parker (ML21879, ML21880, ML21890) and the associated specimen deposited at LSUMZ (see images in Prop 1052). In the description, the authors address SACC proposal 1052 and the subsequent discussion. They make a valid criticism of my original proposal in that I misinterpreted the reasons why Lopez-Lanus (2015) suggested that the Piura population might be a new taxon (I assumed it was because it had the puttering vocalization, when Lopez-Lanus apparently was using the hooted notes--“territorial proclamation vocalization” in their words--as the main character defining the taxon). In my defense, Lopez-Lanus (2015) only compared the Piura birds to magellanicus, and not to nigrescens, in his text account dealing with the vocalizations of that population, so I concluded that this comparison was because they both shared the puttering vocalization, which was still unknown from nigrescens. I also admit that I misunderstood Lopez-Lanus’ (2015) conclusions where he did, indeed, suggest that nigrescens be elevated to species status apart from both magellanicus and virginianus (under which he still kept nacurutu). On the other hand, Lopez-Lanus et al. (2026) themselves erroneously concluded that SACC only split off B. magellanicus and B. nacurutu from B. virginianus, with nigrescens considered a subspecies of B. nacurutu. However, if one views the SACC page for Strigidae, it is clear that B. nigrescens was accepted as a species from this taxonomic change as well (posted on the proposal page in November 2025, before the fieldwork reported in Lopez-Lanus et al. 2026).

But to turn our attention to the meat of Lopez-Lanus et al (2026), I am quite surprised by the conclusions reached and the evidence provided to reach them. Apparently, Lopez-Lanus visited Huancabamba, Piura, Peru, in March 2026 to revisit the site where Parker recorded his two pairs (Cruz Blanca, a ridge to the west of town that separates the temperate cloud forest of the Pacific Slope from the arid valley in which Huancabamba sits) and made recordings of Bubo there and in the arid valley. While there, he also obtained evidence of the presence of B. magellanicus (photos of live rescued individuals taken by others and one recording he made himself: XC1157933) from lower, more arid habitats around Huancabamba town, which is quite an interesting development! Reviewing the two new recordings asserted to be of B. jalca, deposited in both XC and ML (XC1157937/ML661880868 and XC1157939/ML661880378 respectively), I find them such poor quality that I cannot hear an unquestionable Bubo vocalization in either recording, even after cleaning up the sounds and boosting the signal in sound software! I cannot say if they support his hypothesis that there is a truly distinct vocalization matching the Parker recordings 46 years later or not. In addition, the XC versions of these recordings note (in the comment sections) that none of the Lopez-Lanus recordings from this fieldwork were visually confirmed by actually observing bird (to verify morphologic characters). A further baffling revelation is that Lopez-Lanus et al. (2026) used my own recording from Cajamarca, Peru, (XC139660/ML67491881; over 250 km to the SE and across the Marañon river from the Piura site) as a representative vocalization of B. jalca as well! Despite the fact that I described the habitat (the bird appeared to be singing from a Eucalypt amid arid rock pillars at an elevation well below treeline,--decidedly not jalca) and mentioned that only one bird was detected vocalizing (but I also state that I did not see the bird, so again: plumage type was not verified), they interpreted the recording as being a duet between a pair (!). Further, they state (in Fig 4 IV) that the puttering trailing the hoot was “omitted” in the first of the two vocalizations audible in the recording; in fact, a passing car drowns out the sound and I can say (since I was making the recording) that the bird puttered after each hoot! I will note that the importance of the mention of habitat, jalca, is because the authors assert that it is an important character to separate the new species from B. nigrescens (which is found, by comparison, in paramo according to Lopez-Lanus et al, 2026), so the fact that the Cajamarca bird was absolutely not in jalca makes me confused why that recording was used as confirmation of the species in the locality, yet other recordings from the Peruvian Andean localities were not? Thus, the Parker recordings remain the primary evidence of the distinctive voice of B. jalca.

One of the main characters that Lopez-Lanus et al. (2026) used to define Bubo jalca is that it, and B. nigrescens, are the ONLY two Bubo Horned Owls to show sexual dimorphism in their territorial proclamation vocalizations when duetting. They state in the paper under “Diagnosis: Vocalisations” that “The principal component of the territorial advertisement call of male Bubo jalca exhibits a vocal pattern opposite to that of the remaining Bubo of the Andes” and “It is further segregated from all other Bubo, except B. nigrescens, by the production of sexually dimorphic (rather than monomorphic) antiphonal duets; and from B. nigrescens by the distinctive characteristics of the male advertisement call.” Without confirmation that the vocalizations assumed to be male vocalizations by the authors are, in fact, given by males (and with an N=2!), as they use inference based on the collected specimen deposited at LSUMZ was a female, therefore the remaining bird in the second of the Parker cuts must therefore be a male. Whereas this may be true, I am reluctant to accept this inference as fact, as it is not clear when the specimen was collected with respect to the recordings made (I have used MLNS sound archive extensively, as well as visited and archived sounds there personally. The comments added by short-term techs, rather than the original recordists, often can introduce error, and assumptions mentioned in Appendix I of Lopez-Lanus et al., 2026, about the sound recordings and museum specimen involved are not safe ones to make as the basis for confirmation of which sex produced which vocalization). Unless Parker spoke on his recordings confirming that the specimen was collected at that point, and, unfortunately, he didn’t, I am skeptical that we can trust the events as the comments on the MLNS pages state. I will further add that listening to pair duets of any member of the Bubo Horned Owls in the Americas will clearly show that all populations have sexually-dimorphic phrases (this has been well-known in North American populations, e.g., Kinstler 2009, Artuso et al 2022), which goes counter to Lopez-Lanus et al.’s statement above. Despite their statement that B. magellanicus shows no sexual dimorphism in vocalizations, I hear differences in note-pitch and emphasis (“HOO-HOO” with level notes and “hu-HOO” with the second note higher; I will not make assumptions about which song belongs to which sex) between birds in duet recordings. Note-pitch, emphasis, and pattern (number of notes), differs in nearly all duet recordings of Bubo Horned Owls throughout the Americas.

It is noteworthy that Lopez-Lanus et al. (2026) made no effort to review phenotypic or molecular characters in the diagnosis of their Bubo jalca, which seems a flagrant move in current avian taxonomy! However, they stated when providing the images of the two B. magellanicus from Huancabamba that they are “unequivocal[ly]” that species without giving any explanation as to why. Although I agree that the adult image (at least) appears to fit better to B. magellanicus (based on the fine barring below and paler upperparts), I cannot say with certainty that the juvenile bird is (the color saturation seems high and skewed too warmly, so I am not certain I can take it as true to life). Lopez-Lanus provided a sound recording (XC1157933) he identifies as B. magellanicus from near the locality of the juvenile specimen, but as stated above, did not visually confirm the identity of the vocalizing bird. If the two Bubo do indeed occur in the Huancabamba area in such close proximity, this makes this site worthy of additional exhaustive study . Phenotypic and genetic (as well as more in-depth vocal, obviously) comparisons of individuals from here would be exceptionally interesting.

Lopez-Lanus et al. (2026) clearly state that they carried out no playback experiments (and this probably explains why the birds were so far away as to be effectively inaudible in his recordings). In the absence of any other information about interactions between Bubo jalca and B. magellanicus, it seems that how one would respond to playback of the other would be exceedingly important. What sorts of interactions would take place between them would be a very important question to test while in their presence at the locality. Again, the authors never actually visually confirmed that the voices they heard (and nominally recorded) were of the taxa claimed… so we don’t even know how confidently we can accept the identifications of those vocalizations (also see my comments above about the assertion that the recording I made in Cajamarca has been reidentified as B. jalca with no obvious justification).

Recommendation: In the end, I find the evidence provided in Lopez-Lanus et al. (2026) to be unconvincing, particularly since the only real evidence provided is still only the Parker recordings, which are of only 2 pairs of Bubo from one locality (and an associated specimen that was not phenotypically analyzed by the authors in any useful way). Making sex-for-sex comparisons of the vocalizations between B. jalca and other Bubo taxa is fraught with circular logic about sex assignment. Further, now that it seems possible that B. magellanicus may indeed come in contact with B. jalca at this locality, the possibility of interbreeding is once again on the table (despite unconfirmed assertions that this is not possible in Lopez-Lanus et al, 2026), and this could have potential effects on the vocalizations of the birds Parker (and, presumably, Lopez-Lanus?) recorded here. What the Piura population represents may simply be typical B. nigrescens, only that Parker recorded agitated or excited vocalizations that are not commonly-recorded from the species otherwise (although ML573946951 certainly seems to match it pretty well). The small sample size of vocalizations of both B. nigrescens and B. jalca are far too small to say how much variation is present within those respective populations; Kinstler (2009) makes clear that B. virginianus is not just limited to one territorial proclamation vocalization, so why would we expect that to be the case for any other Bubo? Conversely, it is still possible that B. nigrescens and B. magellanicus locally interbreed around Huancabamba, potentially resulting in a hybrid swarm that subsequently could result in non-typical vocalizations from this population. The arguments put forth by Lopez-Lanus et al. (2026) against the Piura population having hybrid origins illustrate a fundamental misunderstanding of hybridization, hybrid character expression, and, ultimately, circular logic.

The authors made little effort to anchor their offered evidence in documented observations. We readers simply have to accept assertions they made by inference and unsupported leaps of logic. This is sloppy science to say the least. Thus, I consider the description of a new taxon here, let alone a new species, of Bubo is extremely premature here.

Vote: YES/NO to accept Bubo jalca as a species apart from B. nigrescens.

Literature Cited

Artuso, C., C. S. Houston, D. G. Smith, and C. Rohner (2022). Great Horned Owl (Bubo virginianus), version 1.1. In Birds of the World (N. D. Sly, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.grhowl.01.1

Kinstler, K. A. 2009. Great Horned Owl Bubo virginianus vocalizations and associated behaviours. Ardea, 97(4): 413-420.

López-Lanús, B. 2015. Análisis domparativo de las vocalizaciones de distintos taxa del género Bubo en América. Hornero 30:69-88.

López-Lanús B., G. Alberca and A. Ugaz Cherre. 2026. Confirmation of a new owl species (Strigidae: Bubo) endemic to the jalca of the Huancabamba Andean Depression, Peru. Audiornis 6:2-53

Dan Lane, August 2026

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Vote tracking chart:

https://www.museum.lsu.edu/~Remsen/SACCPropChart1044+.htm

Comments from Robbins: “For many obvious reasons, I vote NO for recognizing this as a species.”

Comments from Niels Krabbe (guest voter): “As did Dan, I find no new evidence of Ted's recordings being anything other than nigrescens. My remarks under Proposal 1052 still stands. So, I vote NO to proposal 1090.”

Comments from Remsen: “NO. For the list of reasons by Dan too long to summarize here, the evidence for this being a new species is nearly nonexistent. The quest to describe a new species seems to have outpaced the evidence to support it.”

Comments from Areta: “NO, for the many reasons put forward by Dan. As we´ve discussed before, there are several interesting pieces of the puzzle of Bubo that need to better fit in order to fully understand what is going on where the ranges of magellanicus and nigrescens approach or abut. The work by López-Lanús et al. 2026 fails to provide critical evidence for the existence of a new species or to appropriately characterize the zone of interest.

“Beyond the lack of evidence, it worries me that the editor of this custom-made journal has been the sole or lead author of all the published works up to date. An on-line journal tailored to publish whatever opinion one may have should not be called a journal, but rather a blog. Of course, the peer-review literature is no panacea, but the self-pleasing act of publishing nomenclatural acts with the backup of an ISSN and presumably fulfilling the ICZN requirements is worrying.”