Crested grouse

[Jim W]

I am in the process of working pictures of 4 different grouse I took last summer on my cross-continent road trip.  The use of crest as a field mark has me confused.

• National Geographic "Complete Birds of NA" says: "Spruce, Dusky and Sooty Grouse are uncrested".
• The word "crest" does not appear on the Cornell birdsna.org web site's detailed description page for Dusky Grouse.  I suppose that doesn't mean they can't have one.
• However, Macaulay Library shows a few pictures of Dusky Grouse with a crest.
• Worst of all, Cornell's allaboutbirds web site, on it's comparison between Ruffed Grouse and Dusky Grouse has an inconsistency.  The text says Dusky Grouse are "without the short crest", but the picture they chose of a Dusky Grouse has a crest!  (Screen shot below).

My questions:

• Is a crest on a grouse useful as a field mark?  Does a crest rule out any species (e.g. Spruce or Sooty)?
• Conversely, is the lack of a crest useful as a field mark?  Does lack of a crest rule out Ruffed Grouse?

Here is the screen shot of the allaboutbirds page that has me flummoxed (I added the yellow circles and lines). 

Below that are three pictures of one of the grouse I am working on.  For various reasons (including its nice crest!) I am pretty sure its a Ruffed Grouse.  Maybe someone can confirm?  Picture was taken on 7-23-18 just outside of Waterton Lakes NP in southern Alberta.  My other 3 grouse all lack crests.  I suspect I will be posting them for confirmation once I have finished my own analysis.

Web page inconsistency:

 

Waterton Lakes bird:

 

Edited December 18, 2018 by Jim W

[geoffclarke]

I have no experience with any of them, but this sure looks like a Ruffed Grouse based on plumage alone. Lacking some tail feathers?

[blackburnian]

Yes, Ruffed. 

[adrian]

Not positive, but perhaps it has to do with the way the bird holds its feathers. I assume pretty much any bird can look crested if it holds the feathers of its crown erect, as the pictured Dusky Grouse appears to be doing. However, some birds have crown feathers of such length that it always lends a crested look, even when not held erect (as I assume is the case with Ruffed Grouse).

All the photos I can see of Ruffed Grouse from an appropriate angle show a crest, but perhaps some don't show it.