Sunday, 24 March 2013

Dark-eyed Juncos

This time, hopefully, things won't be as confusing as last time, as I think I've learned a thing or two...

First things first. Dark-eyed Juncos have a plethora of subspecies. These subspecies are often grouped into... well, groups! And for the most part, the groups we deal with here in Ontario are Oregon, Cassiar, and the nominate and most abundant in Ontario: Slate-colored.

To be clear, the latin names of these are:
Oregon = montanus, oreganus, shufeldti, and others
Cassiar = cismontanus (some people try to divide them into southern and northern groups/subspecies...)
Slate-colored = hyemalis - to be clear, Cassiar Juncos are considered a subspecies of Slate-colored by some, and a hybrid between Oregon and Slate-colored by others.
Pink-sided = mearnsi... this subspecies is within the Oregon group, but I'll present it separately from the other Oregon Juncos.

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The following photos focus on female Juncos as they are the more confusing of the two genders.
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Here's our usual Slate-colored Junco:
Photo from here

This one is probably a male Junco. The things to notice are the grey flanks, that connect to the grey breast. The division between white and grey across the breast is straight across the belly (i.e. it isn't noticeably curved concave or convex). The bill has a dark tip which isn't always the case but certainly not unexpected based on the birds and photos I've been seeing.


From here

This female is similar to the male, but is browner on the flanks and back. The flanks, however, are mixed with both grey and brown unlike some of the other subspecies outlined below. As a result, there isn't a clear division between the grey bib and the brownish flanks. The grey of the head appears to be a lighter grey than the male. And the grey - white division on the belly is generally straight across.


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Next up is the Cassiar Junco:

-this is the presumed hybrid population between Slate-colored of the East and Oregon of the West:

Photo from surfbirds posted in Jan 2004 


Photo from surfbirds posted in Jan 2004 

Both photos are of the same bird and most people seemed to agree that this was a Cassiar Junco, not an Oregon Junco, on the oceanwanderers site.
The flanks don't stand out as bright brown/pink but they are mostly brown (not mostly grey), they do have a bit of grey in them. The back doesn't have very much brown. The bib has a curved convex shape, unlike typical Slate-coloreds of the East.
The bird was caught and photographed in Connecticut.


Here's another Junco that I also think is a Cassiar:

Photo from here

The flanks aren't very bright brown/pink, and there seems to be a bit of grey mixed in as well. However, the bib/hood does stand out very well, and the bib has a convex shape which gives the impression of an Oregon Junco. But, there isn't enough red/brown on the back to make it a 'perfect' Oregon Junco. So, considering the location (Chicago), the lack of brown/red on the back and mantle makes me think that it's within the realm of Cassiar Junco.

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Oregon Junco:

From here

This bird, in my opinion, is a great example of a female Oregon Junco. The flanks are a bright salmon pink, there's a nice division between the pink upper flanks and grey bib. The head and hood (including the bib) are a dark grey and have a convex shape across the belly - but not dark enough for a male. Another important feature is the extent of brown/red on the back. This colouring even extends into the scapulars, coverts, and tertials.
And it was photographed in Colorado, where one can expect to see Oregon Juncos!

From here

This bird is also another female Oregon Junco. This one seems to be a first winter bird (due to the brown eyes, and brown on the head). The flanks, again, are a nice soft pink and don't have any grey in them. The nice division between the upper flanks and grey bib are noticeable. Also note the convex shape to the bib. The back is quite brown/red which, again, extends into the coverts and tertials.
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Pink-sided Junco:
Photo from here

I'm not going to go into too much detail on this subspecies (which is part of the Oregon group). But the dark lorals (dark area between the bill and eye) are a good indication for this subspecies. Other important features are: the broad pink flanks that extend relatively far towards the legs, and the bluish/grey head.

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As with many difficult to identify species and subspecies. A combination of features are needed to be sure of what you're seeing.

So if you're going to ID an Oregon Junco in Eastern North America some things you should definitely be seeing:

-Light brown/pink flanks with no grey. The flanks should reach right up to the 'upper' flanks and contrast nicely with the grey bib.
-The bib should be convex, not a straight division between the white belly and grey bib typical of Eastern Juncos.
-The back should have a lot of red/brown. It not only needs to be bright, but also extend into the tertials and coverts making the red/brown stand out all that much more!

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Some interesting comments that I wanted to highlight from the oceanwanderers site.


"I suspect that Cassiar Juncos tend to be labelled as "Oregon Juncos" when they show up in the East, and labelled as "Slate-colored Juncos" when the show up west of the Rockies.

"David Sibleys brown adult female under Slate-colored seems to fit well within any broad intergrade population".

"The bird arrived in late December and stayed through late April. It arrived as a very red bird, and changed to a relatively normal pale gray Slate-colored female-type Junco by the time it left (it was banded so I was able to follow its progress)"


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I'll post some of my pictures soon to try and work out what they are. And also steal photos of Juncos from around Eastern North America and try to wring out what they really are...

If you have any photos of unusual Juncos, send them to me :-)




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