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Redpoll
Challenge in 2007: This is a major redpoll winter in southern
Canada and the northern United States. The legendary George North of
Hamilton once saw all four North American redpoll subspecies (races) in the
same flock on 23 March 1958 (Curry 2006). Fifty years later this could
be the winter to do it again. On 15 December 2007, Ron and Doug Tozer
found a big "snowball" Hornemann's Hoary Redpoll (nominate
hornemanni)
on the Minden Christmas Bird Count. This is the rarest redpoll in
southern Canada. On 14 December 2007, I saw two "Greater" Common
Redpolls (rostrata) at our feeders in Toronto and there have been
several other recent reports. With these two High Arctic subspecies
and probably record numbers of "Southern" Hoary Redpolls (exilipes) in
flocks of "Southern" Common Redpoll (nominate flammea), we have all
four North American subspecies in southern Ontario this winter. Below
I summarize some basic information needed to understand and identify
redpolls.
Taxonomy: The American
Ornithologists' Union (1998) recognizes two species: Common Redpoll (Carduelis
flammea) and Hoary Redpoll (C. hornemanni). Each has two subspecies
(races) breeding in North America. Discussion about lumping or
splitting redpolls has been off the "radar screen" in recent years.
The four subspecies are described below.
1. "Southern" Common Redpoll (nominate
flammea): This is the commonest of the four subspecies in
southern Ontario. It is the standard to which the other three are
compared. In most plumages, it is noticeably streaked on the sides,
undertail coverts and rump. However, adult males in winter have more
contrasting whiter rumps (fewer streaks and often pinkish) than on
worn breeding birds. Adult males are pink-breasted. First year males
are somewhat darker and often washed with light pink. Adult females
usually lack pink (sometimes tinged) and first year females are the
darkest and most heavily streaked of the four age/sex classes.
2. "Greater" Common Redpoll (rostrata):
This large and dark subspecies breeds on Baffin Island and Greenland.
Greater Redpolls are a winter visitor in small numbers to the southern
parts of eastern Canada from Ontario to Newfoundland (Godfrey 1986)
and to the northeastern United States. Greaters are more frequent than
Hoarys in some winters (Pittaway 1992). The Greater is larger
(averages 14.0 cm compared to 12.5 cm for flammea) and heavier. Other
field marks are the Greater's thicker bill and somewhat darker and
browner coloration with conspicuous heavy streaking on the underparts
usually extending to the undertail coverts. Adult male Greaters have
"red of underparts less extensive and less intense" than flammea
(Godfrey 1986). Males lack red on the malar area,
which flammea males usually
have (Beadle and Rising
2006). Some observers describe Greaters as House Finch-like. See the
excellent identification article on Greater Redpoll by Beadle and
Henshaw (1996) in Birders Journal 5(1):44-47, illustrated by Beadle.
The differences between the two Common Redpoll subspecies are usually
obvious when the two are together for comparison (Peterson 1947).
3. "Southern" Hoary Redpoll (exilipes):
This subspecies breeds in the Low Arctic and much of its range
overlaps that of the "Southern" Common Redpoll (flammea). It is the
much commoner Hoary subspecies, and is similar in size to the flammea
Common Redpoll. During redpoll flight years, it is usually possible to
find a few classic adult male exilipes Hoarys. Compared to the
"Southern" Common Redpoll, they are more frosted with white rumps,
have lightly streaked flanks and very lightly streaked to pure white
undertail coverts. Adult females and especially first year females can
be noticeably streaked. Exilipes Hoary is similar in size to flammea
Common, but may look slightly larger because of its whiter plumage.
Hoarys have shorter, more obtuse (stubby) bills imparting a
distinctive "pushed in face" appearance. Many females are identifiable
by overall paler coloration and bill shape. Individuals appearing
intermediate between exilipes and flammea are best left unidentified.
4. "Hornemann's" Hoary Redpoll (nominate
hornemanni): This is the largest, palest and rarest
redpoll. Hornemann's breeds in the Canadian High Arctic Islands and
Greenland and is a great rarity in southern Ontario and Quebec.
Hornemann's is larger (averages 14.0 cm) than "Southern" Hoary (exilipes)
which averages 12.5 cm. It is whiter with less streaking on the sides
and flanks and has immaculate white undertail coverts. Adult males
have less pink than exilipes, some showing only a trace of pink
suffusion on the breast. Females and first year birds are recognizable
if compared directly to the two small subspecies, flammea and
exilipes,
by their larger size. See the excellent article on redpoll
identification by Czaplak (1995) in Birding 27(6):446-457. His photo
of Hornemann's on page 448 is correctly identified in my opinion. Note
larger size of the Hornemann's in the photo in American Birds
42(2):239, which is reproduced on Jean's website link below. See also
Doug Tozer's photo and Ron Tozer's detailed description of the recent
Ontario "Hornemann's" on Jean Iron's website link below. See David
Sibley's website link below.
A. Why is there so much plumage variation in
redpolls? A flock of one subspecies of the Common Redpoll
(flammea) will show four plumage types: adult males, adult females,
first year males and first year females. Since there are four redpoll
subspecies, a large flock potentially could have 16 plumage types,
plus considerable individual variation.
B. What is the Greenland Redpoll?
Historically, the name Greenland has NOT been used in North America to
describe the rostrata "Greater" Common Redpoll (Peterson 1947, Todd
1963, Bent 1968, Terres 1991, etc.). However, Greenland Redpoll is the
European name for "Greater" Redpoll (Newton 1972, Jonsson 1993, etc.).
Most North American publications use Greenland Redpoll for "Hornemann's"
Hoary Redpoll (Nash 1905, Macoun and Macoun 1909, Taverner 1953, North
1983, etc.). The name Greenland causes confusion. Most of our
Hornemann's and Greater Redpolls are coming from Canada, not
Greenland. To avoid confusion, it is preferable to include the
subspecies scientific name after the common name, particularly when
first mentioned: (flammea), (rostrata), (hornemanni), and (exilipes).
TAKE THE REDPOLL CHALLENGE: This
is the first winter in decades to match George North's Ontario record
of four redpoll subspecies in one day. Even more amazing, all four
were in the same flock. I am not aware that North's record has been
matched in southern Canada or the northern United States. However,
Roland C. Clement saw all four subspecies on 12 March 1944 at Indian
House Lake in northern Quebec (Lat 56 15' 0 N / Long 64 42' 0 W) south
of Ungava Bay close to Labrador. Clement in Todd (1963) reported "a
feeding flock of mixed migrants that contained ten rostrata, thirty
flammea, two hornemanni, and about six exilipes."
Three websites with redpoll information and photos.
1.
http://www.jeaniron.ca/2008/commonredpolls.htm (Three photo
pages of redpolls: "Southern" Common Redpoll - subspecies nominate
flammea; "Southern Hoary Redpolls - subspecies exilipes;
"Northern" Common Redpolls - subspecies rostrata)
2.
http://www.jeaniron.ca/2007/Redpolls/CommonredpollsTO.htm (One
page of photos)
3.
"Hornemann's" Hoary Redpoll, "Greater" Common Redpoll and Redpoll
Challenge
Acknowledgements: I thank Michel
Gosselin of the Canadian Museum of Nature for information on redpoll
taxonomy and identification. Doug Tozer kindly provided the photo of
the recent "Hornemann's" Redpoll in Minden. Jean Iron and Ron Tozer made
many helpful suggestions.
Literature Cited: I can supply
full references.
Email Ron Pittaway
Minden and Toronto ON
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