Most of the Northern Flickers we see here in southern BC are of the "Red-shafted" or cafer race. They are here year-round, but more plentiful in fall and winter. They breed throughout the western US and much of Alberta and British Columbia.
The "Yellow-shafted" or auratus race has a much more eastern distribution, although the western edge of its breeding range extends into northern BC and the Yukon. Flickers are more migratory than most woodpeckers, and some of the yellow-shafted birds winter down here amid their red-shafted relatives. So at this time of year, when you see a flicker, be sure to check the colour beneath its wings and tail. As the breeding maps show, the two forms overlap and they do interbreed, so it is also possible to find intermediate forms.