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posted February 22nd, 2011; last edited February 22nd, 2011 –– David Sibley Michael Butler of Marathon, Ontario sent me the remarkable photo below, showing all four taxa of redpolls (four subspecies, two species) in one view (see more at his blog here: http://northshorenature.blogspot.com/ From left to right this photo shows a typical (Southern) Common Redpoll, Hornemann’s (Greenland) Hoary Redpoll, Greater (Greenland) Common Redpoll, typical (Southern) Hoary [...] posted March 11th, 2008; last edited April 9th, 2010 –– David Sibley Maybe I should change the name of this blog to “All about Redpolls”, but I’ve received a few photos that I wanted to pass along, making the point that “Greater” Common Redpoll is not just an eastern specialty. The AOU checklist and the BNA account report that this subspecies winters regularly from Labrador west to [...] posted March 10th, 2008; last edited April 9th, 2010 –– David Sibley A new photo by Dan Berard shows what looks like an intermediate large redpoll, and should be added to the discussion in my previous post. photo copyright Dan Berard, used by permission – 7 Mar 2008, Millbury, MA Dan says both of these birds were about the same size and both were larger than the [...] posted March 7th, 2008; last edited April 9th, 2010 –– David Sibley Maybe we are just more aware and looking harder for “Greater” Common Redpolls (Carduelis flammea rostrata) this winter in Massachusetts, or maybe it’s really an exceptional winter, but there is no doubt that they have come south in significant numbers. I have seen them on a couple of visits to Dan Berard’s feeders in Millbury, [...] posted March 3rd, 2008; last edited March 3rd, 2008 –– David Sibley In considering the true status and distribution of Hoary Redpoll, I realized that I had overlooked one significant source of information – the Christmas Bird Count results. While Common Redpoll nests throughout the boreal forests across the continent, Hoary is virtually unknown as a breeder east of Hudson Bay (ignoring the “Hornemann’s” Hoaries in Greenland [...] posted February 13th, 2008; last edited February 13th, 2008 –– David Sibley The question of age variation has come up repeatedly in redpoll discussions, so I finally tried to find an answer to the question of just how important age-related variation in plumage might be. And based on published studies the answer is … not very important. Seutin et al. (1992) studied redpolls at Churchill, Manitoba using [...] posted January 14th, 2008; last edited April 9th, 2010 –– David Sibley Redpoll identification is challenging because Hoary and Common Redpoll seem to show an unbroken continuum of variation from pale to dark, and there are no fully reliable differences. So birders have to rely on a subjective assessment of overall color and struggle to define the threshold for confident identification. Virtually all birders see redpolls only [...] posted January 8th, 2008; last edited January 8th, 2008 –– David Sibley I’m reposting here some comments I just sent to ID-Frontiers, about a pale redpoll in Illinois and another in Massachusetts: The comment under these photos on the ILBIRDS forum giving the bird an index score between 11 and 12 is, I would say, overly generous. The undertail coverts that we can see (not much) seem [...] posted January 5th, 2008; last edited January 5th, 2008 –– David Sibley [edited 12 and 14 Jan, 2008, adding comments about the index] I’ve been thinking about redpolls more, and had another, more careful, look at Troy’s 1985 paper, which is filled with interesting observations and some serious “food for thought”. First of all, Troy identified redpoll specimens using a character index, which is a well-established method [...] posted January 2nd, 2008; last edited January 2nd, 2008 –– David Sibley On the MOU website: a Hoary photo Here from Minnesota (where Hoary is expected and the threshold is low) of a pale Hoary-type with a relatively long bill Some other recent Hoary photos from Michigan – scroll left and right to see about 5 shots From Ontario this photo and the two following show a [...] |
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