My #$%^#%% laptop send the email before I was ready to send it. Here is the whole missive.
Tony
Hi all:
The Brant that Colorado birders ogled in Larimer County from late October to late November and which now appears to be in Jefferson County has been submitted to eBird by various observers as Brant, Atlantic Brant, and Gray-bellied Brant. I am writing to beseech eBird users for more consistency in reporting this individual, as it would save me time and headaches as one of the Colorado eBird reviewers.
To what form of Brant is the beast referable?
While Gray-bellied Brant remains a poorly known and understood form of this waiting-to-be-split-by-the-AOU species, Colorado's own Steve Mlodinow is, perhaps, the authority on the form among birders. Steve's identification piece on Gray-bellied Brant that appeared in a 2006 issue of Birding is required reading for anyone endeavoring to identify the form in the field. Unfortunately, this article is NOT one of the ones available on the website of the American Birding Association (publisher of Birding). Perhaps, Mr. Ted Floyd can convince the powers that be to make it so available; it has been over seven years, and it would be most useful to ABA-area birders without access to hard copies of the issue (which would be most of them).
Steve has posted in this venue that he believes that the Loveland Brant fits best as Gray-bellied, and not as Atlantic, which was its original field ID. While I have no field experience with Gray-bellied Brant, I have extensive experience with Atlantic Brant, and this bird would stand out like a sore thumb among Brant at Cape May, where I have seen 10s of 1000s. The only real concern about the bird being identified as a Gray-bellied Brant is over the possibility of Brant hybrids. However, the bird appears to be a card-carrying, middle-of-the-road Gray-bellied Brant, and I see no need to invoke hybridization to explain its appearance.
In my quick perusal of some of the pictures taken at Loveland and at Chatfield, I find it difficult to determine whether it is the same bird. The largest problem with this effort is that the bird is in active molt, and its appearance changed in the month that it was in Larimer County; the secondary problem is that I don't have access to enough good pictures of it from late in the Larimer occurrence and nowhere near enough of the bird at Chatfield recently. However, it seems to me that Occam would think that it is more likely that an exceedingly rare Gray-bellied Brant would have changed locations in Colorado than that a second individual showed up south of Larimer County after the Larimer bird disappeard.
eBird treatment
I would appreciate anyone submitting on either the Loveland or Chatfield occurrence enter it as either Brant or, preferably, Gray-bellied Brant. The Loveland occurrence has, I believe, been documented to the Colorado Bird Records Committee and that august body will be making the semi-final decision on the taxon (I assume that it will be accepted as Gray-bellied, but...).
Sincerely,
Tony
Tony Leukering
http://www.flickr.com/photos/tony_leukering/
http://aba.org/photoquiz/
-- The Brant that Colorado birders ogled in Larimer County from late October to late November and which now appears to be in Jefferson County has been submitted to eBird by various observers as Brant, Atlantic Brant, and Gray-bellied Brant. I am writing to beseech eBird users for more consistency in reporting this individual, as it would save me time and headaches as one of the Colorado eBird reviewers.
To what form of Brant is the beast referable?
While Gray-bellied Brant remains a poorly known and understood form of this waiting-to-be-split-by-the-AOU species, Colorado's own Steve Mlodinow is, perhaps, the authority on the form among birders. Steve's identification piece on Gray-bellied Brant that appeared in a 2006 issue of Birding is required reading for anyone endeavoring to identify the form in the field. Unfortunately, this article is NOT one of the ones available on the website of the American Birding Association (publisher of Birding). Perhaps, Mr. Ted Floyd can convince the powers that be to make it so available; it has been over seven years, and it would be most useful to ABA-area birders without access to hard copies of the issue (which would be most of them).
Steve has posted in this venue that he believes that the Loveland Brant fits best as Gray-bellied, and not as Atlantic, which was its original field ID. While I have no field experience with Gray-bellied Brant, I have extensive experience with Atlantic Brant, and this bird would stand out like a sore thumb among Brant at Cape May, where I have seen 10s of 1000s. The only real concern about the bird being identified as a Gray-bellied Brant is over the possibility of Brant hybrids. However, the bird appears to be a card-carrying, middle-of-the-road Gray-bellied Brant, and I see no need to invoke hybridization to explain its appearance.
In my quick perusal of some of the pictures taken at Loveland and at Chatfield, I find it difficult to determine whether it is the same bird. The largest problem with this effort is that the bird is in active molt, and its appearance changed in the month that it was in Larimer County; the secondary problem is that I don't have access to enough good pictures of it from late in the Larimer occurrence and nowhere near enough of the bird at Chatfield recently. However, it seems to me that Occam would think that it is more likely that an exceedingly rare Gray-bellied Brant would have changed locations in Colorado than that a second individual showed up south of Larimer County after the Larimer bird disappeard.
eBird treatment
I would appreciate anyone submitting on either the Loveland or Chatfield occurrence enter it as either Brant or, preferably, Gray-bellied Brant. The Loveland occurrence has, I believe, been documented to the Colorado Bird Records Committee and that august body will be making the semi-final decision on the taxon (I assume that it will be accepted as Gray-bellied, but...).
Sincerely,
Tony
Tony Leukering
http://www.flickr.com/photos/tony_leukering/
http://aba.org/photoquiz/
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