Redpolls from Greenland and from Iceland are called one (sub)species by some people, namely rostrata. I think this is not correct, because both redpolls are quite different.
First, Greenland Redpolls are migratory birds and they mostly are migrating in winter time outside of Greenland. A part of them are migrating to Iceland, a part to Canada and the USA and a small part migrate to Europe, especially to Scotland.
Redpolls from Iceland are not realy migratory birds. I think these birds never leave Iceland. Many redpolls are caught on Iceland, ringed and released. Until today no one caught a ringed Icelandic Redpoll outside of Iceland (based on personal comments from Icelandic bird ringers during my visit to Iceland, April 2016)*. Icelandic Redpolls move a lot within Iceland.
Finally, the appearance of both Greenland Redpolls and Icelandic Redpolls differs. I’ll explain this below, based on my own pictures.
Greenland Redpoll, Greenland, March 2013. Characterized by a dark chocolate brown appearance.
Greenland Redpoll (rostrata)
These birds are characterized by their dark chocolate brown appearance. Even in flight, the warm colours are noticeable. They are overall brown-tinged with heavy streaking on the upperparts and underparts. The rump is white, but heavily dark streaked. Adult males have a minimal amount of red / pink on their chest. Almost all Greenland Redpolls look the same; there is little variation. So, they’re quite uniform. A Greenland Redpoll is slightly smaller than a Hornemanns’ Arctic Redpoll (Acanthis hornemanni hornemanni) and bigger than a Mealy Redpoll (flammea). Finally, this redpoll has a strong bill, compared to a Mealy Redpoll.
The description above is based on my own sightings and my own pictures, collected during a few trips to Greenland and pictures from other photographers (taken in Greenland):
- Tom Brereton
- Jean Iron
- Chris Gibbins
More about Greenland Redpolls, click here.
Greenland Redpoll, Greenland, March 2013. Heavily streaking on the upperparts and underparts. White rump, but heavily streaked.
Greenland Redpoll, Greenland, March 2013. Dark chocolate brown appearance.
Greenland Redpoll, Greenland, March 2017. Flanks heavily streaked.
Greenland Redpoll with a Hornemann’s Arctic Redpoll, Greenland, March 2017. Greenland Redpoll is slightly smaller than Hornemanns’ Arctic Redpoll.
Icelandic Redpoll (islandica)
Most of the Icelandic Redpolls are heavily striped on their flanks, darker and bigger than Mealy Redpolls. Unlike the Greenland Redpolls, these redpolls are far from uniform: some birds are dark, some are pale. Some are heavy (25 grams) or less heavy (12,5 grams). Some birds are big, others are small. Even the size of the bill is variable. The darkest Icelandic Redpolls are indistinguishable from Greenland Redpolls. There are also very pale Icelandic Redpolls. They look like Arctic Redpolls but with heavily flank streaking and a larger bill. Martin Garner suggests in his book 'Winter' that this pale redpoll is probably an undescribed Arctic Redpoll. I think these redpolls are within the variation of Icelandic Redpolls. Like Greenland Redpolls adult males Icelandic Redpolls have a minimal amount of red / pink on their chest.
The description above is based on my own sightings and my own pictures, collected during my visit to Iceland, April 2016.
*Note, there is a report of a probably Icelandic Redpoll outside Iceland. This redpoll was ringed in Iceland (2 January 2018 at Akureyri) and recaught at Skagen bird observatory in Denmark on 14 October 2018 (a picture of the bird). If this bird is an Icelandic Redpoll, than it is evident Icelandic Redpolls sometimes leave Iceland (probably just a small number). It’s also possible this bird is a Mealy Redpoll, got lost in Iceland, ringed and flew back to Denmark. Yann Kolbeinsson, thanks for this additional information.
More about Icelandic Redpolls, Click here.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. Note: amount of flank streaking.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. A pale redpoll.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. Note: amount of flank streaking.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. Note: amount red / pink on chest.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. Note: amount of flank streaking and strong bill.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. Note: tiny bill.
Icelandic Redpoll, Kópavogur, (south-west) Iceland, April 2016. Note: strong bill.
Icelandic Redpoll, Akureyri, (north) Iceland, April 2016. A dark Icelandic Redpoll or probably a Greenland Redpoll.
Icelandic Redpoll, Akureyri, (north) Iceland, April 2016. A dark Icelandic Redpoll or probably a Greenland Redpoll.
Icelandic Redpoll, Akureyri, (north) Iceland, April 2016. A pale Icelandic, indistinguishable from Mealy Redpoll.
Icelandic Redpoll, Akureyri, (north) Iceland, April 2016. An ‘Arctic Redpoll’-type with a completely white rump. See also a movie of this bird.
Icelandic Redpoll, Akureyri, (north) Iceland, April 2016. Note: amount of flank streaking.
Mealy Redpoll (flammea), Barrow, Alaska, October 2018. A ‘look alike’ Greenland Redpoll. Probably not chocolate brown enough. This bird has the same size as a Coues’s Arctic Redpoll (exilipes): too small for a Greenland Redpoll. Beside this, a Greenland Redpoll is not to be expected in this corner of the world.