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Someone else’s Song Sparrows

December 16, 2010
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I love the little Song Sparrows that nest in the ornamental junipers in my neighborhood.  They may well be the quintessential little brown jobs, seemingly made specifically to overwhelm new birders, but regardless of whether you know what to make of them when you see one, anyone with any ounce of attention can hear them sing throughout the summer.  Their elaborate rattly, chirpy song that’s somewhat similar but slightly different to what Song Sparrows sing from coast to coast.

My summer birds are classic Song Sparrows.  Quite literally so, as they hold the moniker Melospiza melodius melodius, the pleasant-singing pleasant-singing song-finch.  A song so nice they named it twice.

What that double denomination really means is that my breeding Song Sparrows are the nominate subspecies, essentially the first one described, so they get the honor of the double species name.  What gets complicated is that Song Sparrows have an additional 28 described subspecies, each denoting a different population distinct from the rest but many with a significant amount of overlap.  While it can be exceedingly difficult to place any individual sparrow to its proper subspecies, what can be clear enough is that some birds are different.  For all the times that I’ve watched my breeding Song Sparrows in my neighborhood, I can recognize them in an instant.  I know that they’re chunky and reddish, with thick brown streaks on their breast like someone went to town with a dull Burnt Sienna crayon (here’s a old post containing a photo of one of my summer birds).

But these birds poking around my feeder now are slimmer and darker, with thinner dark brown streaking.  They are clearly not of the same stock as the birds that sing from my junipers every summer.  But what are they?  And is it even possible to tell?

Song Sparrows at any time of year in this part of the country are of the four subspecies in the Melodia group.  M. m. melodia have long since split for the south, and I think I can effectively rule out the coastal subspecies M. m. atlantica by range alone,  which leaves two contenders, M. m. euphonia and M. m. juddi.

Pulling out the old Pyle guide I’ve tried to make heads or tails of this bird and I just don’t think I can.  The differences between euphonia and juddi essentially come down to a “medium-short and stout bill” versus a “medium-small and slender bill”.  Between an upper back of “medium-pale brown with dark brownish streaking” versus an upper back of “medium dark-grayish with reddish-brown streaking”.  That’s a lot of equivocation for supposedly distinct populations.

It’s an interesting exercise, but the differences between these two groups are less quantitative and more a matter of degrees, a continuum line between the stoutest billed, brownest backed individual juddi and the slenderest billed, grayest backed euphonia.  Is it possible to come to some sort of acceptable solution?  Maybe with the bird in your hand but not likely before. And even though I’ve always been sort of interested in Song Sparrow subspecies and whether or not they can be identified in the field, it’s clear to me now that even with good photos and a reference right in front of me, it’s all but impossible.

But that’s ok.  The important thing is that it makes you stop and think about the birds in your backyard and how even something as apparently ordinary as a Song Sparrow cause you to consider birds in a way you might have not otherwise done.

These are birds from the north.  They are not my Song Sparrows, they’re someone else’s.  And that’s enough for me.

3 Comments
  1. December 16, 2010 9:38 am

    I am so glad you brought this up Nate. The differences in song sparrows across the USA and Canada is amazing. I too have observed the song sparrows in my backyard in Nova Scotia very carefully and they are quite different looking from those even ten miles away. There is also considerable difference
    in the local Savannah sparrows with inbreeding from the “Ipswich” clan I suspect as they are larger and paler (they occur also in the southwest of Nova Scotia, not only on Sable island 100 miles offshore.) It would be impossible to do a study of all the local colorations but I guess the genetics is doable as you suggest.

  2. December 16, 2010 2:27 pm

    I’ve been seeing a ton of Song Sparrows in my neighborhood over the past few weeks. They generally don’t show up in the yard, but they do gather in a park a few blocks away. There are so many that they’re clearly coming from somewhere else. I’m not really sure if they’re from a short distance dispersal or a longer distance migration. They do show a lot of variety, especially in their breast markings.

    In an essay a few years ago (I think in Birding), David Sibley used Song Sparrows as an example of why he chose not to illustrate subspecies for most birds in his guide. There is so much natural variation, and gradations are so subtle, that subspecies are often not identifiable in the field.

  3. Nate permalink*
    December 17, 2010 11:10 pm

    @Jane- Thanks much! I do like those Ipswich Sparrows, they show up on the Outer Banks of NC in the winter and I’ve encountered them on a few occasions. In the most recent issue of Birding, Rising’s article on subspecific variation in Savannah Sparrows mentions that the Ipswich interbreeds from time to time with the conventional onshore Savannahs. I don’t know how often it happens, but apparently often enough. Very striking birds in any case! I’ll bet the Song Sparrows you see in Nova Scotia are the atlantica ssp, I seem to remember Pyle mentioning they nested in Maritime Canada.

    @John- The Song Sparrows are definitely tough, and it wouldn’t surprise me if some of the described subspecies were superfluous and the differences turned out to be more clinal as in the Savannahs. I understand why Sibley didn’t illustrate them all, and I wonder if in our haste to put a name to everything we fail to look at the bigger picture showing the case for many Song Sparrow subspecies isn’t as strong as we thought.

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