Winter is the time to see redpolls. These birds of the Arctic head south for the winter. They are named for their red polls (i.e., crowns, see previous posting), and seem to come in two species: Common Redpoll, Hoary Redpoll. Of the two, the most likely one to be seen around here is the Common (if it is even seen at all). However, a paler, less strongly banded Hoary, from the high Arctic, may occasionally be mixed among them.
However, recent research finds almost no genetic difference between these supposedly different species. Their variations seem to be less the result of genes as of gene expression. Do we care whether we are seeing differences between species or between gene expressions? It remains fun to see the regional variations as the occasional (high Arctic) Hoary appears among the Common.
The Common Redpoll shows strong banding on the sides.
The Hoary Redpoll shows weak banding on its sides. (Picture by Derek Kite.)
In the conventional scheme, the pale breast of the bird on the left would be considered a Hoary Redpoll.
This head-on view of a flying redpoll probably would be considered a Common. (Picture by Derek Kite.)
While this would likely be thought of as a Hoary Redpoll.
Derek Kite’s pictures are used with permission.
Wow those are wonderful shots