Saturday, May 30, 2015

A Study in Yellow

Yellow Warblers. How splendid that such beautiful birds are relatively common in our area! The best place I know to see and hear great numbers of them is Lake Erie Bluffs in eastern Lake County.  Just listen!

Many of us know the common song that is presented in field guides: “sweet-sweet-sweet-little more sweet!” This kind of description is called a mnemonic device, and some people find these quite helpful.  I think they work best for songs that don’t have many variations. For Yellow Warblers, the "sweet-sweet-sweet" mnemonic fits the rhythm of their primary song, but doesn't really work for their other songs.

Their most common song can easily be heard in the foreground of this recording. There's also a Song Sparrow and a Spring Peeper in the background. The sonogram below shows only the Yellow Warbler song, and I think you can see it's relatively simple.

They can sing this song a little slower and add a couple of extra "sweets"...

They can also sing this song a little faster and shorter. 

Now about those other songs: – this is a “theme and variations” species. All the recordings (and photos) I've used in this post are from the same area of Lake Erie Bluffs, and there were other song variations as well. I won’t go through all of them, but I’d like you to get an idea of the range of possibilities.

Here’s one where there is a strong, descending note at the end. This song is rather common and this is how the sonogram will appear:

And can he switch back and forth? Yes! You’ll hear each song twice (but you'll just see the two song types once in the sonogram below).  Look how different they are!

Let's listen to (and look at) one more.

By now, you can almost tell how this one will sound just by looking at the sonogram. It will start with something like "Sweet-sweet-sweet" but will be followed by a rapidly repeated pitch. As you listen, you may hear more than one bird singing this new song. There is also a bird singing the primary song and yet another singing the second song form we just heard in the preceding tracks!

You may be wondering how you'll ever sort out these songs. 

First, let me assure you that you don’t have to learn all their songs at once! It’s highly unlikely that you could do so even if you are very diligent and determined.

Here are some ideas for your comparisons:

The pitch range (highest and lowest notes) will be very similar and so will the tone quality. That’s why it sounds like the same singer.

Listen for the phrase length of the song. This is important. Yellow Warbler songs are not very long, and they’re all about the same length. If you look at the earlier sonogram that compared two different Yellow Warbler songs, you’ll see that the song lengths are essentially the same. 

It's also helpful to compare the Yellow Warblers songs to those of other species that share their habitat. For example, Common Yellowthroats and Song Sparrows can often be heard with Yellow Warblers, but those birds would have longer song phrases. 

The Common Yellowthroat's song will sound repetitious as if it's going around in a circle, and the Song Sparrow's will be far more complex. Here's a Yellow Warbler followed first by a Common Yellowthroat, then by a Song Sparrow. (Each song is sung twice.)

If you can find a Yellow Warbler and watch him sing, you’ll confirm the singer and will also be more likely to remember the song variant you just heard. (I do realize that except during April, this can be a challenge. Even though they are very bright, they are often in shrubs and obscured by leaves.)

Study their behavior. Listen for a sudden change in song form, or if you hear a nearby bird that has a similar voice and is singing back and forth with the Yellow Warbler that’s closer to you.

It’s rewarding to really get to know Yellow Warblers. Yes, they’re common – and they’re beautiful, feisty, fast, engaging, acrobatic, and often not so far above eye level that you’re going to get a case of “warbler neck” watching them. Listen for them near ponds, stream, wetlands, or in meadows, and if you want to hear huge numbers of them, go to Lake Erie Bluffs! 

1 comment:

  1. Nice post, Lisa. Out here in Illinois we have another, highly frustrating variation. Their alternate song, instead of starting like their primary song, has rising phrases, so that the whole is practically identical to the chestnut-sided warbler's song. If there is a difference between the two, I have yet to discover it. You inspire me to make recordings in a future year, and see if your kind of analysis helps. Regards, Carl