Cassiar Junco?

[paulos]

I have had a couple darker and grayer Juncos around the yard in the last couple weeks. A female is clearly a slate-coloured. I noticed a male with a very dark hood, extending further on the breast than an Oregon, with charcoal gray on the sides. However, the back had some brown, clearly contrasting with the hood. I am wondering if this may be a Cassiar Junco. It is not uniformly dark gray as a slate-coloured. Here are some photos.


CassiarJunco? by Paul Foth, on Flickr

CassiarJunco? by Paul Foth, on Flickr

CassiarJunco? by Paul Foth, on Flickr

CassiarJunco? by Paul Foth, on Flickr

[paulos]

I got another look, and there is a decidedly clear line from the dark head to the gray/brown back. Given that and the pattern of the front and sides, I do believe it is a male Cassiar.

[Randy]

This is interesting Paul. I actually wasn't aware of Cassiar juncos until your post. Neither Sibley's nor iBird identify them as a subspecies but eBird has posted an alert to users to post sightings of this subspecies.

I did some brief research online and it seems there may be some debate about whether this is a subspecies or simply and intergrade between Oregon and slate-coloured, which makes sense when you look at the bird and the frequency.

Does anyone have any thoughts or expertise in this area of discussion?

[paulos]

Randy, if you check in the big Sibley Guide of North America it is listed as the "Canadian Rocky Mountains" Junco, under Slate-coloured. Sibley doesn't always use subspecies names unless they are notable, like Myrtle warbler.

[Jamie]

There's been a Cassiar Junco vistting our feeders for the last couple years. It has a brown back but is otherwise like a Slate-colored.

Randy I don't really know. I think it MIGHT be a Slate-colored x Oregon subspecies, but I'm not entirely sure. BTW you just reached 1000 posts.

[Randy]

Interestingly the recent issue of Bird Watcher's Digest had an article on all the subspecies of junco. I figured people here would be interested in seeing a summary map from the article:



The article also did suggest that Cassiar junco was an intergrade between slate-coloured and Oregon.

[zack]

024 by Henry Wall, on Flickr Some of the Junco`s that i have at my feeder. There was one that showed up briefly this afternoon and was unlike any that i have seen here, it was Jet Black from it`s head to the tip of it`s tail. 

[Gord]

Is it the one in the top left corner? Sure does look dark and possibly a Slate-coloured sub species?

Randy, great article to share. Thanks for posting it.

The juncos are fun to look at. Not all can be identified for certain as they do hybridize and also, are surprisingly variable even among the same subspecies depending on gender and age. I don't have to go out to the fields to agonize over gulls if I want some identification challenges. I can always stay home and look at my juncos!

[Deleted]

As Gord says, juncos can present an interesting challenge in your own yard. I've been trying to sort out these juncos for years and I would scrounge through several books on sparrows comparing numerous photos or illustrations, trying to figure them out but without much clarity. Among dozens of the usual local Oregon subspecies, we get a few Slate-colored subspecies individuals each winter in our yard, but that was about all I could be sure of. More recently, going mostly by what Sibley says, I understand the Slate-colored subspecies, found across most of eastern and northern North America, to be distinguished by, among other things, the bottom of the bib being a more or less horizontal or level line across the lower breast, instead of the broad U-shaped bottom of the bib shown in the Oregon subspecies. The line is seldom nice and symmetrical, often a bit ragged, but it's usually easy to tell which of the two general patterns each individual fits into. Also, Slate-colored subspecies males are more uniformly dark, almost black (except for their undersides, of course), with little or no brown on the back or lower sides, and showing no real contrast in colour between the hood / bib, and the back / sides. Oregon males (our local subspecies) have a darker hood and bib, sharply contrasting with the back and sides. The Slate-colored females are gray with varying amount of brown on back and lower sides, and also show the horizontal bottom of the bib.

However, I occasionally see a male that has the pattern of the Oregon subspecies (the U-shaped bib) but the colour of a Slate-colored subspecies, that is, no brown on back and sides and a contrast between the black hood / bib, and the dark gray back / sides. This I take to be the cismontanus form, also known as the Cassiar Junco, and also what Sibley labels Slate-colored, Canadian Rocky Mountains. There seems to be some agreement, but no certainty that this is an intergrade between the coastal Oregon subspecies and the eastern Slate-colored subspecies. It would make sense, as the presumed range of this form is where Oregon and Slate-colored subspecies ranges apparently overlap. According to Sibley, females of this presumed intergrade form are often indistinguishable from females of the Oregon subspecies (which vary in the amount of brown shown on back and sides). If Sibley can't tell the females apart, I'm not going to claim I can.

In short, if I see what looks like an Oregon male except it has no brown but only gray on its back or sides, it's probably the cismontanus form or Cassiar Junco. However, it's stlll likely an open question whether other individuals of this presumed intergrade might show a different combination of characteristics of the two subspecies. And yes, I realize that what we call the Oregon subspecies actually represent a group of several subspecies that are so similar we can't tell them apart, rather than just one subspecies, but it's convenient to refer to the Oregon subspecies or Oregon group. Same for the Slate-colored subspecies (actually a group of subspecies, too).

It makes sense that eBird wants us to report this form to help get a better understanding of it.

This is how I've come to sort of make sense of it, mostly based on Sibley. On this basis, I would call the male near the top of Paulos's photo, showing a more or less horizontal bottom to its bib, a Slate-colored subspecies, not a Cassiar or cismontanus form.

But I don't pretend to have it all figured out and I certainly welcome discussion.

Stan

[birderbert]

There are lots of Cassiar Juncos around right now. Plumage is highly varied but one rule seems to hold true ie grey on the sides & dark brown on the back!

Cassiar Junco 14s by BirderBert, on Flickr

[Deleted]

Well, now I am more confused. (I've never felt I wasn't at least somewhat confused about these junco subspecies!)

Birderbert (and everyone else on here as well), your photo may well be a Cassiar Junco, but I would find it very helpful if someone could explain why in some detail. As a starting point, do you think it`s a male or a female? For species having as much plumage variation between males and females as juncos have, that`s an important starting point, and it could be an indication that there may be more than one simple rule for identification. If Sibley is anywhere near right in his illustrations, male Cassiar Juncos should have little or no brown on them, and females should have lots of brown on them, enough brown to make it difficult to say they`re not Oregon females. So that raises questions for me about saying that brown back and gray sides is a primary guide to Cassiar Junco. I'm not picking on you, it's just that whenever I approach this kind of thing for my own birding activities, I feel like I need to know the reasons why. I've checked more than a dozen field guides and I can`t find anything that says brown on the back and gray on the sides is a primary mark for Cassiar Junco. So again, not picking on you, but where does this rule come from? If it's from a recognized source and it is in fact reliable, it would be very useful and I would be happy to have it available. If it's something you've come to through your own personal observations, it could also be very useful, but how do you know you're actually identifying Cassiar Juncos when you derive this rule, or apply it? Please don`t take this as being critical of you -- I`m just hoping you or others on this site can give more light on this that will help us all. Some of the other guides don`t completely agree with Sibley, indicating that Cassiar or cismontanus have some brown on the back for males. So I`m still searching for help.

As examples of other guides I checked (and used to rely on in past years):
-Sparrows and Buntings, by Clive Byers, et al, 1995 (part of an authoritative international set of bird ID guides) says that cismontanus average slightly browner on the mantle (than nominate Slate-colored) and females average more pinkish-brown on the flanks.
-The Sparrows of the US and Canada, by James Rising, 1996, says that cismontanus are intermediate between nominate Slate-colored and Oregon, and females have flanks washed with pink or brown rather than gray.
-Sparrows of the US and Canada : The Photographic Guide, by James Rising, 2003, says the males of cismontanus are browner than the other Slate-colored forms, and females have flanks washed with pink or brown rather than gray. He also says that most of the Slate-colored that winter in coastal BC appear to be this form.
-Stokes field guide says for cismonantus - Male with blackish gray hood that contrasts with gray back, wings and flanks. Female with gray head that blends to or slightly contrasts with brownish back, wings, and flanks.
In light of these that all say females have pinkish or brownish flanks, you can see why I might be doubtful about gray sides being an indicator for cismontanus females, at least.
Other guides such as NG, Kaufmann, etc. don`t give specific descriptions. Nor do my birding apps such as iBird, Peterson, Audubon give specific help. My Sibley app gives similar info to the big Sibley guide. My NG app says it needs to be updated to work with iOS 11, so I can`t access it.
I don`t have access to the online Birds of North America series, and if someone does, maybe they could share with the rest of us what it says that`s relevant.

I've also googled images of Cassiar Juncos (as I`m sure others do as well) and I find a variety of images, some that follow Sibley's pattern and some that don't. Having worked as an academic librarian for over 30 years, I do know that anyone can post anything on the internet and call it anything they like, but that doesn't necessarily make it reliable, so I don't give as much credibility to internet photos, especially when the author/poster is unknown or not a well known birder, as I do to published works of recognized authors. I`ve also found in the past that googling images of a species often results in a whole bunch of images that include many that aren`t necessarily the same species and often aren`t clearly distinguished from the species that was searched for. So I`m always cautious about using internet photos as a basis of identification.

I hope others will share helpful information here that will help us all with ID of this one.

Stan

[zack]

Gord the one at the top is what i would call being midway to the one i mentioned. There are 2 like this one that are a dark grey to black on top but pure white on the bottom and these are only ones out of about 2 dozen Junco`s in my yard. THe one i saw yesterday was as black as the Ace of Spades and i didn`t see any white on it.

[paulos]

Stan, one source where they do seem to present an Oregon-like dark hood, brown back male cassiar junco is the ebird Northwest portal. There is a post by Bill Tweit about identifying them here. The photo depicts a very Oregon-like male. Here is the description:

They are not as easy to find and identify in the midst of an Oregon Junco flock as Slate-colored, since their pattern is similar to Oregon and since the females may be very difficult to distinguish. The drawings in Sibley, labelled as Canadian Rocky Mountain, are quite good. Males have a black hood, shaped liked an Oregon hood, sharply delineated from gray flanks and a gray back. The male at my feeder shows a brownish tinge in the gray back with all gray flanks. In low light, or when viewed head on, Cassiars are not obviously different and not easy to identify, while either sex of Slate-color is generally recognizable with even a quick glance due to the convex hood shape and lack of contrast between hood, flanks and back.

If he is wrong, and we shouldn't expect brown on an adult male Cassiar junco, I am at a loss for identifying the first pictured junco. From a back view it looked almost exactly like an Oregon, with the brown back and very dark hood. From the front I thought it was a darker Slate-coloured. It essentially appears like an Oregon with a longer, more erratic hood.

I am not sure if Cassiar is a catch-all for those in between Oregon and Slate-Coloured. Is there any way an OregonXSlate Couloured hybrid would be different from a Cassiar junco?

[Deleted]

Thanks for the link, Paulos. That's helpful. Bill Tweit is a well known birder and he references Steve Mlodinow who is also a well known birder. Both have contributed extensively to knowledge of bird ID in the Pacific Northwest over the years.

Tweit agrees with Sibley in general terms. To me, looking at Sibley, a male cismontanus should simply look like a male Oregon but with gray instead of pink/brown on the sides, and with gray and no brown, or only tinged with brown (not strongly brown) on the back. Though several of the older guides I referenced in my previous post do say some brown may be seen in the back, I caution that since normal Slate-colored are dark gray with virtually no brown on the back, saying cismontanus averages slightly more brown than Slate-colored is not saying cismontanus should have a brown back, but that some may have a brown tinge to the gray on their back.

Definitely, they don't stick out in the normal crowd in my backyard the way Slate-colored do, though the very few cismontanus I've noticed have been distinctive, and I've also noticed a few that weren't so distinctive and puzzled me.

Looking at the top photo you refer to, I see what looks like either a male cismnontanus with rear flanks much lighter than expected, or a male Oregon with its bib extending abnormally much farther back along the sides than usual. Also, whichever it is, its back looks lighter than usual, though light and exposure by the camera can also produce unexpected effects, of course. Maybe such unusual variants can be expected occasionally with intergrades between two subspecies. Or maybe even it's just a variant without being an intergrade.

Of course, all of the above applies to males only. I trust Sibley that female cismontanus are not normally safely distinguished from female Oregon.

Stan

[paulos]

Stan, thanks for the great clarification regarding the back colour and variation.

In regards to the top bird in question, the lighting is not the best as I took the photos with my phone through binoculars. You can see that in the last photo the barely visible back looks much darker. It probably was not as light as it appears in the first picture. I believe it was not as brown on the back as the nearby Oregon males.