Hairy Woodpecker - Picoides villosus - subspecies discussion

Hairy Woodpecker - Picoides villosus -  Discussion of subspecies 

Sometimes in Michigan, someone will suggest, on a birding email list, they've observed a Hairy Woodpecker with plumage matching that of the pacific northwest subspecies. Often the distinguishing characteristic used for the ID is the overall dusky tint to the white plumage compared to bright white plumage of the eastern subspecies. However, the amount of white spots on the wings is often ignored. Discussion usually turns to the prominent white spotting on the observed subject and, if it was observed during nesting season, it is suggested the white plumage is dusky as a result of the bird moving in and out of the nesting cavity; resulting in "dirty" plumage.

I've been a bit confused by the Hairy Woodpeckers at Bandon State Natural Area, and in southern Oregon generally, because I've observed more white spots on the wings of some birds than I expected. A transplant from Michigan, I anticipated seeing very little white spotting on the wings. Also, the white plumage of some birds did not strike me as all the dusky. Further experience over the past three years suggests my initial experiences were not representative.

This morning I observed and photographed a fledged male juvenile working a dead himalayan cherry tree in Bandon. This bird was had dusky white plumage and little white spotting on the wings. Also, notice the red cap covering the crown determinative of a juvenile as oppose to the adult male red plumage on the back of the head.

Compare the white spots on the wings with those of Hairy Woodpeckers in Michigan. 

Hairy Woodpecker Nest Sight at Point Aux Chenes wetland in Michigan's Upper Peninsula -  June 13th, 2010

The juvenile, observed this morning, has the least amount of white spotting that I've observed on Hairy Woodpeckers on the south coast. That may be because it is young, however, the juveniles back east have much more spotting than this individual captured in the first two photos above:

Chipper Woods Bird Observatory - Carmel, Indiana
Compare Photos: http://www.wbu.com/chipperwoods/photos/hwood.htm

I wonder whether there are multiple subspecies on the south coast of Oregon?

Hairy Woodpecker nest sight on Swamp Lakes in Michigan's Upper Peninsula - May 31st, 2009