Saturday 23 March 2013

Juncos

A couple weeks ago I came across an interesting Junco.
The flanks were noticeably buffy, it had a grayish hood that contrasted with the brownish back, and the hood came down to form a bib on the breast. All the other juncos that were feeding next to it were the usual dark grey mantled juncos with no contrast between the head and back, their flanks were more solid grey.

I simply assumed that the different bird was an "Oregon" junco without looking into it very much.

I returned today hoping to get some photos and was surprised to see two Oregon-like Juncos. The first thing I noticed was that one was more Oregon Junco-like than the other...

Unfortunately, I only managed to get photos of one of the birds (the less convincing one!)

After some research I'm totally confused, so I'll post some photos of the one bird, and try to get out to study and photograph them again...

All four of these photos are the same bird. It is probably a Cassiar (cismontanus) Junco which some people seem to think is a hybrid between Slate-coloured and Oregon. Or it could just be a very brown Slate-coloured Junco...

First thing that contrasts with the usual Juncos around here is the dark bib, and buffy brown flanks.


The back is also fairly brown and the flanks appear to have no grey at all.


The tip of the light-pink bill is dark.

What do you think?

Cassiar juncos should, apparently, have some gray in the flanks - but I don't see that in this bird. So that would indicate an Oregon junco?

However, the grey bib of this bird isn't very convex, it almost seems to be a straight-ish line where the grey contrasts with the white belly. Which makes me thing it's intermediate between Slate-colored and Oregon...


I tried doing some research on this but there seems to be a ton of confusion and discrepancy with a lot of overlap in plumages...

If you're looking for some confusion, check out these links:
http://www.oceanwanderers.com/JuncoID.html
http://www.oceanwanderers.com/JuncoID2.html

The 10th junco from the top on this page seemed very similar to the one I photographed today - that person thought it was a very brown Slate-colored Junco... I don't know how you could rule out a hybrid though especially considering that I don't see a distribution in Junco variation that approaches todays bird. In other words, there is some variation around the Slate-colored group (females and immatures being a bit browner than adult males), and then a jump (with very few to no intermediates) to the brownish flanked ones (i.e. Cassiar/Oregon Juncos). That jump, to me, definitely seems good for a different population or at least a hybrid...

It'd be neat if someone could compile a ton of Junco photos to see if there is a distribution from the dark grey Slate-colored Juncos to the brown of the Oregon Juncos. Something like that is obvious for Redpolls which is what makes them super hard and unreliable to identify and leads to many differences in opinion (i.e. there's no obvious differences between the groups)...

eBird wasn't much help either. There are many more records for Oregon Junco vs. Cassiar Junco in our area of North America even though Cassiar should be more expected (or maybe not???):





I've probably confused anyone who has read this post...

But, honestly, what do you think of this mess?!

I'll try to get some more photos soon of the two birds I saw today and give them the attention they deserve!