Your name Aaron Beerman
Bird identification Tundra Bean-goose
Date(s) April 19, 2019
Time of Day 5:40 pm
Location Pasture adjacent to Crooked River Wetlands, Prineville, OR
Lighting and Weather Conditions Partly cloudy
Details Description of Bird: (This bird was widely reported and many photos are accessible on eBird and el e he e I ill n de ail he bi d a ea ance e en i el b in ead f c n ke fea e important for comparison to the relevant subspecies of Bean-goose). These are some things that we observed. The bird appeared slightly smaller in proportion from the nearby Canada Geese (Moffitti). At m angle f ie hi bi d head a ea ed nded al h gh m e e me ha m e al han the two previous documented Oregon Tundra Bean-geese). Its bill was relatively long, thick based, and the culmen mostly straight and lacking a significant curve. The gape noticeably broad and deep set. The bill color was black with yellowish-orange band which covered a little less than 1/3 of the bill length. After review of several photos the bill nail appeared oval shape when facing straight on rather than concave on top and bottom. In my perspective the neck of the bird appeared consistently short and stocky during the length of our observation, as well as in review of images taken on later dates by others. Although hard to estimate, the legs also appeared orange in color and average length, not long. No vocalization was noted during our observations.
Similar Species Taiga Bean-goose middendorffii subspecies is really the only other comparable species, in terms of appearance and geographic range. Although the separation of these two species can be at times be challenging, there are several important feature of the Prineville bird that I believe point away from middendorffii. From what I have read, the Taiga Bean-goose is broadly characterized by its long swan- like neck, elongated bill, flat fore-crown and generally taller, prominent appearance. Most subspecies exhibit a wide yellow bill band and less pronounce lower mandible. Crucially, it is has been said by other more experienced with these subspecies that the overall jizz of the bill, neck and body structure are the e en ial fea e f di ing i hing he T nd a and Taiga ecie i e i ea to over analysis characteristics such as the bill long or extend of bill band coloration. In the case of the Prineville goose, as previously noted, it appeared necked, and short legged, not exhibiting obvious swan-like features. The bills in-set gape, thick based I think better fit Tundra Bean-goose over Taigi.
From: Charles Gates
Here are two photos for my Rare Bird Report to the Records Committee.
Tundra Bean-Goose in Crook County.
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It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so. Mark Twain
Chuck Gates Prineville Bird Club 541-280-4957 Powell Butte, Central Oregon Oregon Birding Site Guide http://www.ecaudubon.org/birding-locations Oregon County Checklists http://www.ecaudubon.org/county-checklists
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TUBG-2019-03 (Tundra Bean Goose) 1st Round Vote July 28, 2019
Accepted, verified: 6 Species Unresolved: 3
ACCEPTED, VERIFIED Could we obtain some of the other photos for our file? or at least links?
I observed and photographed this bird as well, and can provide a description if needed. However, I believe the photos and descriptions are sufficient to identify this bird as a Tundra Bean Goose.
Good photos, and Aaron offers a good analysis comparing this bird with middendorffi Taiga Bean-Goose. I concur with his reasoning and believe this bird is a Tundra Bean-Goose.
Nice write up and photos.
Another high profile rarity that was seen by many, and yet a fraction of the photos have been submitted to the committee.
In terms of the identity of this goose, I am in agreement with this being a Tundra Bean Goose, likely of the subspecies serrirostris The head proportions and especiall the bill seem a little elongated for a serrirostris Tundra Bean-Goose, especially when compared with the Finley Tundra from last Fall Winter but still within range This bird doesn t appear to have as long as a neck I d e pect on a t pical middendorffii Taiga Bean-Goose, a subspecies of the most similarly looking species one must eliminate. The grin patch, from what we can see, appears rather wide, ovular, and deeply recessed. This last feature, a deeply set grin patch seems to slightl favor serrirostris over middendorffii in m opinion Another factor in favor of serrirostris is the overall amount of ellowish coloration on the bill and it s position closer to the middle of the bill According to m research a middendorffii should have a more restricted ellowish patch farther awa from the middle of the bill. As to the overall size of this bird, according to Sebastian Reeber s Waterfowl of Europe North America and Asia There is a relativel strong variation in mass during the annual c cle being lighter in Jan and heavier in Mar-Apr before northward departure I also read that there is some slight overlap in size between the two The shape of this bird s head isn t as flat as I d e pect on a middendorffii and seems better for a serrirostris Also the coloration is somewhat dark showing an almost capped appearance which during m research for the Finley bird, I found pretty consistently on Tundra Bean-Geese and not so much on Taigas. Not sure how reliable of a fieldmark this is, but anecdotally, it seemed to hold up decently well.
I was slightly concerned back in the spring as to how long this bird remained. It was documented in the area for 15 days. This does seem a little on the long side for a seemingly wild goose to linger during spring migration, but not unheard of. The window that this bird was seen, April 19th through May 3rd, does seem consistent with the broader trends of migration of Canada Geese/Cackling Geese through our state. In some reports on eBird, this bird was mentioned to possibly be injured or unwell, sometimes walking with a slight limp, potentially factoring into why it lingered as long as it did. In the past two years in this general area, there have been observations of both Hawaiian Goose and Smew, which were later found to originate from a local resident and breeder with an exotic waterfowl collection. Apparently Chuck Gates reached out to this person and confirmed that the Tundra Bean Goose was not a part of her collection. See this checklist for the comment: (https://ebird.org/view/checklist/S55164287). One final note in regard to provenance, in some photos on eBird, this bird can be seen to have its hind toes intact, strengthening the case that it was in fact a wild bird.
No comments
There are additional photos of this bird on eBird at https://ebird.org/species/tunbeg1/US-OR-013. This bird has characteristics typical of the subspecies serrirostris. The bird has a relatively short neck, a relatively dark head, a broad deep gape, a relatively thick bill, and an orange band near the tip of the bill, all of which are consistent with the subspecies serrirostris.
SPECIES UNRESOLVED I think this is a Tundra Bean Goose, but due to the complexity of the ID, discussion and a second round of voting would be warranted. This bird seems on par for Oregon's previous two records of Bean Goose, which have been labeled as Tundra. In particular, the bill is fairly short with a deep base and only a little bit of orange. The neck seems short.
I appreciate Aaron's careful analysis of why he thinks this is a serrirostris (i.e, Tundra Bean Goose) and not a middendorffii (eastern subspecies of Taiga B G). However, I'm wondering if we haven't been too glib about the recent Bean Geese in Oregon. Back when they were all "Bean Geese", the wisdom was to avoid trying to identify to the subspecies level "except by locality of observation" (Madge & Burn). Of course, once they were split everyone was motivated to determine a species. It's not clear to me that there have been subsequent advances in identification that now justify being certain which former subspecies we're looking at.
I agree that this is a Bean Goose, but I'm not 100% convinced that the photos and description sufficiently eliminate the possibility that this is a middendorffi Taiga Bean Goose. The forehead profile seems quite flat in one photo and the bird appears long-necked in one photo and short-necked in the other. The bill seems to be somewhat in between middendorffi and serrirostris in shape and length in the photos, at least as shown in Reeber. Reeber also notes that some birds originating in East Asia can appear intermediate between the two with some overlap in overall size. I'm leaning towards agreement with the reporter, but feel there is enough uncertainty to take this to the second round. I also wonder about provenance with the recent cluster of exotic waterfowl that have appeared in the area, including Nene, Smew, and Emperor Goose. The timing of this bird is also a little odd with most (or all?) other records of Bean Geese showing up in the western U.S. in December or January. There is no indication in the report that any observer noted whether or not the bird was missing one of its halluxes. If it has a hallux on both feet that wouldn't necessarily eliminate the possibility of captive origin, but if it is absent that would certainly be a strong indicator of past captivity. I'm not suggesting this bird is in fact an escapee and it certainly appears to have acted like a wild bird (probably more so than the recent Emperor Goose), but we should perhaps be more cautious than usual because of the factors noted.
TUBG-2019-03 (Tundra Bean-Goose) 2nd Round Vote – October 7, 2019
Accepted: 7 Species Unresolved: 2
ACCEPTED, verified Thank you, [another committee member], for the link to the additional photos. [Another committee member] is right to raise caution over the species identity, but Madge and Burn is not the best reference to use in this case, because it was written from a western European perspective where multiple subspecies winter, making the ID issues are much greater. I found Dement'ev et al. very useful in separating serrirostris from middendorffi by bill shape and overall proportions, and Reeber is very useful.
It might be informative to hear from experts who have had a lot of experience separating the two species. That said, I agree with most everyone's comments about the stated reasons why this is a Tundra, not Taiga Bean Goose. On the other hand, I think it is a reasonable stance to vote "Species Unresolved" based on the two photos submitted.
No comments
For the reasons Aaron Beerman gave, the photos look fine or a Tundra bean Goose.
This is indeed a tough ID problem, but based on the two previous bean goose records from Oregon (which I both saw in the field) and my experience with both species in Europe, I still feel that this bird falls within the "Tundra" Bean-Goose spectrum, and I feel comfortable accepting it as such.
This is a tough call due to the similar Taiga Bean-Goose. However, in online photos I very consistently see that Taiga is longer-necked and has a more sloping forehead than the bird depicted in these photos. Overall, Aaron's description seems very convincing, and makes for a good case when coupled with both submitted and unsubmitted photos of this bird from eBird. [Another committee member's] concerns from the 1st round are well taken, but I think we should accept this as a Tundra Bean-Goose; we can re-evaluate if new ID criteria are established or if we see a trend in N. America of more ambiguous, less text-book classic individuals begin to appear. Also, while it shouldn't be a major consideration, it does seem that Tundra is the more common of the two in North America - especially in recent years. I don't think there's a need to worry about provenance. North America's records are scattered between logical locations: W. Alaska, the central flyway (some Great Plains records), and the Pacific Northwest down into California. While most have shown up with migratory geese in late fall and winter, a spring record of one with Canadas makes plenty of sense. Other waterfowl, such as Garganey, will similarly winter further south and show up for sometimes extended periods of time at stopovers on their way north. The bird could easily have wintered in California or somewhere in the Southwest.
I'm still not 100% comfortable with the identification of this bird, but when looking at some of the additional photos (thanks for the link Tim), I am just about on board with this bird being a Tundra. There are two features that seem to separate this bird from middendorffi Taiga Bean Goose. First, neck length. This bird's neck appears to be relatively short in most or all photos; it does not seem particularly long-necked. It certainly doesn't appear to hold its neck in a swan-like curve in any of the photos as middendorffi is described as often doing in some sources. The other feature is that the bird's head appears to be darker than its lower neck and body in most photos. This is also consistent with serrirostris Tundra and not middendorffi Taiga, which is described as the most pale-headed of the Bean Goose subspecies. The bird's overall size and bill shape and coloration are equivocal to me, although the bill seems closer overall to serrirostris than middendorffi.
A classic Tundra Bean Goose. Photos and analysis rules out Taiga Bean Goose.
To my eye, the photos adequately eliminate Taiga Bean Goose. I don't think that a Taiga Bean Goose would have all of the field marks that were noted on the bird that was photographed. I tried to summarize those in my first round comments and Nick also went into considerable detail in this regard in his first round comments as well. While they're had escapees in that area, I don't see any evidence that this bird was an escapee.
SPECIES UNRESOLVED [Another committee member] does bring up a good point. In Sebastian Reeber's Waterfowl of North America, Europe and Asia, the author mentions that "It is nevertheless worth noting that some birds in E Asia do not clearly match any taxon, appearing intermediate between middendorffi and serrirostris, closer to the latter in their size and short neck, but resembling middendorffi in rather pale plumage and gentle head shape. The bill is intermediate in length, depth and culmen outline. Such birds have been regarded as westernmost populations of middenforffi or as 'johanseni', but this seems questionable as the influence of fabalis does not appear convincing." Although this is information from just one source, lacking in any statistical significance, I do still feel it needs to be heeded to properly assess this bird. This passage definitely gives me pause in trying to properly asses the attributes of this individual. In light of recent rules that we have added to our bylaws, I hope that my fellow committee members made use of the myriad images available of this bird on eBird. Unfortunately, many caveats of the individual in question fit the description provided by Reeber of certain members of the middendorffi population that do not clearly match any taxon. Revisiting this report, I do now feel it prudent to heed the warnings outlined by [two other committee members] in the first round, specifically about the complexities of separating Taiga Bean- Goose from Tundra Bean-Goose, considering the limits of our current understanding of the species complex and our collective ability to make remote judgement. Even though I feel this individual best fits a Tundra Bean-Goose of the serrirostris subspecies, I am no longer confident enough to say definitively.
I looked at a bunch of the eBird photos, as well as the photos in this submission (including [another committee member’s]). I just don't see anything that clearly puts this bird in one box or the other. I worry that if I went back and looked at the previous "Tundra" Bean Geese reported in Oregon, I'd come to the same conclusion. (So, I won't.)
TUBG-2019-03 3rd round vote July 18, 2020
Accepted: 9 Not Accepted: 0