Mystery Bird: Field Sparrow, Spizella pusilla

tags: , , , ,

[Mystery bird] Field Sparrow, Spizella pusilla, photographed on the Katy Prairie, Katy, Texas. [I will identify this bird for you in 48 hours]

Image: Joseph Kennedy, 6 February 2010 [larger view].

Nikon D200, Kowa 883 telescope with TSN-PZ camera eyepiece 1/350s f/8.0 at 1000.0mm iso400.

Please name at least one field mark that supports your identification.

Review all mystery birds to date.

More like this

Here we go again, another Spizella, but with a brown back with dark streaks, rust-colored crown and eyestripe (right side seen above), gray (winter) face, breast, and sides, and a forked tail (note how the central tail feathers are stacked above and shorter) there can be little doubt that this is a pusillanimous individual...

By David Hilmy (not verified) on 15 Feb 2010 #permalink

Hey Bob, this species is very definitely in Illinois all year round... (although this particular one is probably still in Texas!)

By David Hilmy (not verified) on 15 Feb 2010 #permalink

What! you mean it's not a Chipping Sparrow?

Tough call from this angle. I agree that it's a Spizella, but I'm stumped in terms of definitively narrowing this bird down to species. My initial thought was American Tree Sparrow, but after looking up where Katy, TX is it appears that it's a little south of the normal winter range (according to my Nat. Geo. field guide). Could be a vagrant, but seeing as I have no strong reason to prefer S. arborea over Chipping or Field Sparrow, I'll rule it out as a likely ID.

From this picture, it isn't obvious to me how prominent the eye line is (Chipping's would be darker than Field's). I'm inclined to lean more toward Field Sparrow because the supercilium in this picture, while only barely visible, looks more grey to me than white.

*****

Ok, so after remembering that the picture can be enlarged I'm a lot more confident. That bill is pink.

By Brian Slaby (not verified) on 15 Feb 2010 #permalink

OK, why Spizella?

Spizella are characterized by being relatively small with rounded heads and long tails (and although foreshortening is an issue, one can still see much of the tail past the back as opposed to something like Ammodramus which might not have even been visble) and the tail is forked (as mark explained by psweet in an earlier blog, the central tail feathers are stacked on top of the outer retrices and are visibly shorter, therefore a forked shape)... Aimophila and Melospiza have rounded tails...

within Spizella, American Tree, Chipping, Clay-colored, Brewer's, Field, and Black-chinned are all recorded for Texas but with Katy Prairie so close to Houston, as Brian points out, the American Tree would be a stretch, as would the Brewer's and Black-chinned, and the Clay-colored doesn't winter there but does pass through...

so between the two that are left, the crown seems to me to be the give-away- as also pointed out by psweet in another earlier blog, the darkness of Chipping Sparrows' crowns is due to fine dark streaking amidst the rufous/brown and that is conspicuously absent (which also rules out a lost Clay-colored) and additionally I would expect a median crown stripe but I see two either side of middle...

add the streaked back, gray face and breast as confirming features, we're left with one...

By David Hilmy (not verified) on 15 Feb 2010 #permalink

Speaking of "sparrows", the Cirl Bunting (Emberiza cirlus) is one of my favorites, and the news published today speaks volumes of the matter-of-fact undemonstrative way the RSPB goes about the business of conservation- from 118 pairs in 1989 to 700 pairs in 2003 to 862 pairs last year! Now lets get to work on halting the decline of the Yellowhammer (Emberiza citrinella) too!

"Wildlife-friendly farming, reintroduction scheme and natural reserve boosts cirl bunting population over last seven years." guardian.co.uk, February 15th, 2010

By David Hilmy (not verified) on 15 Feb 2010 #permalink

Hello David,
Coincidentally I saw the largest flock (18) of Yellowhammers I have seen in a long while on Sunday. The problem appears to be a lack of winter seeds due to modern farming practices.

Thanks Adrian, another beautiful bird!

... and I suppose the degradation of hedgerows, whether removed or pruned/flailed, must be contributing to the decline... since I was in school, the UK population has declined by over 60%!

By David Hilmy (not verified) on 15 Feb 2010 #permalink

Yes David, and "a little bit of bread and no cheeeeeeese" is the song I remember most from cycling in the Cheshire lanes during my childhood.

A couple of other points -- Brewer's and Clay-colored can, as far as I can tell, be ruled out by the presence of rufous in the stripes on the back. (I can't imagine using this in the field, though) And the pink wash on the nape connecting the crown to the back strongly suggests Field.

The only thing that bugs me is that I think I can see a dark eye-line -- which shouldn't be there on a Field. I'd like to think it's an artifact of the photo, but I just can't tell.

I considered Cassin's, Swamp, and Bachman's -- they all show a rufous crown. (They were all ruled out by David on the basis of tail shape, but what the hey.) Swamp should be darker gray and rufous. Cassin's has patterned central rectrices -- with wear, the pattern may become indistinct but they should still be the palest feathers in the tail. Bachman's shouldn't show the white edging on the greater wing coverts.

So, I guess it's still a Field Sparrow, and I'll chalk the
'eyeline' up to photo issues.

Paul, I first thought the same about the eyestripe but too many marks said Field so I too put it down to shadow caused by the slight "swelling" (for lack of a better word) just above the orbit on many sparrow species...

of the three others you mentioned, I'm not so sure that Cassin's gets as far north or east as Houston, even in the summer... nor Bachman's that far west, although Swamp does look good for range (wouldn't it show more rufous in the wings and a more definitive gray crown median stripe in winter?)

By David Hilmy (not verified) on 15 Feb 2010 #permalink

David -- you're right about Swamp, there are a bunch of things that don't fit. Cassin's doesn't come that far east, they're a short-grass species, but sometimes it's worth thinking outside the range maps. After all, if a Red-cockaded Woodpecker can nearly reach Wisconsin, and a Red-footed Kite can vacation in Martha's Vineyard, you can rarely if ever absolutely rule something out by range. (Well, maybe Ostriches.) So, sometimes I'll check a bit farther. Incidentally, I believe there is a record for Cassin's Sparrow for Illinois. Bachman's is formerly known as the pinewoods sparrow, since that's what it's tied to -- and while Houston may be a touch west of the pines of East Texas, it isn't very far.

Thanks Paul, you're right- I do remember finding several species in Scotland nowhere near where everyone said they should have been (like a Ring Ouzel on the Isle of Skye and a Chough on the Isle of Mull), although the small island dynamics of the UK had sometjing to do with it...

I must admit I tend to go "oh look, a ---", and then try to work out why it's not, instead of starting "from the top" and working myself down... I see it as a sort of birder's reading vocabulary- once you learn how to phonetically decode unfamiliar words, most of what you read in something like a novel actually becomes a sight-word not requiring you to decode at all... the only time that approach really catches me out is when I'm trying to identify some tropical tree in the middle of the Amazon or Borneo where they all look virtually identical!

By David Hilmy (not verified) on 15 Feb 2010 #permalink

I think it was Kenn Kaufmann who wrote an article on birding by probability, where you first focus on the most likely birds in the area, and go beyond that if nothing fits. He points out that you can rapidly identify most of what you see, but he also points out that despite living in Cape May, he very rarely finds rarities. Not that he doesn't see them, they just don't trigger that "if nothing fits". Which is fine, depending on what you're interested in. (I have to admit that my of best two birds here in Illinois, I misidentified both of them at first.)