Wednesday, February 13, 2008

Adequate but not Correct


Song Sparrow or Lincoln's Sparrow?


Song Sparrow or Lincoln's Sparrow?

This evening I received a comment to my September 2007 blog post "Early Fall Nature Photography" which included a photograph of a melospiza sparrow I had identified as a Song Sparrow. Rather than only post the comment where none would likely benefit from it, I decided it could serve as a lesson on bird identification in a new post.

Dear Mike:

Nice photo of a Lincoln Sparrow, it's not a Song Sparrow. Note the gray supercilium (eyebrow) and the buffy sub-moustachial stripe (line next to the black malar stripe next to chin). These two sparrows are very similar. Lincoln Sp. have finer streaks in the breast and usually show a buffy wash across the streaks. Note the pale buffy eye-ring also. They are slightly more petite looking than Song.

Thanks for sharing your photos,

Debby

This is an interesting case of when an adequate diagnostic description fails to render the correct identification. All of Debby's topographical points are correct: The supercilium is partially gray, there appears to be a buffy sub-moustachial stripe, black malar stripe, a buffy eye-ring, etc. Despite all of these seemingly correct field marks, the bird is in fact a Song Sparrow and not a Lincoln's Sparrow. How do I know? I just know. I can tell simply by looking at it. I may not be able to tell you exactly what it is about the top bird that makes it a Song Sparrow and the bottom one a Lincoln's Sparrow, but I'm confident that my identifications are correct.

As many readers of my blog know, I truly adore sparrows. Of course, loving sparrows as much as I do is mutually exclusive from being able to correctly identify them. That's perfectly acceptable. But how does a birder's skill evolve to the point where they no longer have to run through a checklist of field marks in order to make the correct identification? I can look at either of these species in the field, sometimes only for a fraction of a second, and still make the correct identification in that instant. In fact, it's gotten so bad that I can identify most of them in flight. How is this possible? I don't really know. Perhaps it comes with time and studying these sparrows for countless hours over years.

On Lincoln's Sparrow Pete Dunne once wrote, "There is no trick that could be offered here for making this identification. Only mindfulness will work." And what would I offer to that sense of mindfulness? For one, no birder is infallible when it comes to making identifications and I've been corrected by other birders from time to time. In a moment of excitement, perhaps when being overwhelmed with a great diversity of species, my internal "database" faults and I say something before I realize what I'm even looking at. When I've identified a Lincoln's Sparrow in the field, it's not that a series of field marks were sequentially processed and confirmed that particular species. It's more like having a "little brown job" pop out in the open and the bird's impression just hits you.

I recall once being very intimidated by sparrows. I remember saving sparrow identification once I figured out “confusing fall warblers” but still placing the challenge well before taking on gulls. All sparrows seemed like the same brown little bird with such minor subtleties that I was unlikely ever going to be able to sort them out. I'm not sure how it happened, it just did. Using a variety of field guides will help. Birding with other birders will help. Studying photographs of birds helps, especially close-up photographs by banders. Birding a lot is key - watching what they do, where they are and when.



Song Sparrow


Lincoln's Sparrow

I've always regarded the plumage pattern of a Lincoln's Sparrow to be "tighter" and more detailed. Also, look how thick (and brown) the Song Sparrow's flank stripes are compared to the fine flecks of black on the Lincoln's Sparrow. Sometimes the flank markings on a Song Sparrow appear connected, like in the above example. There's also a general impression of 2 to 3 colors on Song Sparrows, whereas the Lincoln's coloration immediately registers more complexity.

Lincoln's Sparrow


Song Sparrow

All images © 2008 Mike McDowell

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