There's More To The Ear Than Meets The Eye

I attended The Connecticut Ornithological Society's annual meeting today at Middlesex Community College in Middletown Connecticut. There were several things that captured my interest today. The high point of today's events for me, however, was a presentation by Don Kroodsma ( pictured above), author of "The Singing Life Of Birds".

The presentation was excellent but there is no way I can translate that in this post. Instead , I will give a summary of some of the ideas he tried to express.

There is more to birding by ear than just identifying a species by it's song. Don Kroodsma illustrated this point something like this.

Imagine getting together with your friends. You don't say a word to each other. You look at each other, make a positive identification (maybe even using binoculars), and then check each other off on a list.

I don't think the point here is to say that watching birds has no value. Of course, we know how enjoyable it is to study and identify birds. The point is, you are missing out on a lot if you don't pay attention to the vocalizations of birds.

Don Kroodsma noted that the best time to start listening to bird song is about an hour before the sun comes up. Many birds sing different songs at this time than they do after sunrise. I believe that the Eastern Wood Peewee is one example of a bird with a different pre-dawn song.

Don likes to go out in the field with a parabolic microphone but usually does not bring binoculars with him. It is more important for him to know what is on a bird's mind than to see them.

During the presentation , he used audio recordings of birds songs accompanied by sonographs-(visual representations of bird vocalizations) -to illustrate some of his observations. Naturally, you had to be there in order to appreciate this. He slowed the audio of the birds songs as much as 1/10 the natural speed . He said that you need to do this to hear a vocalization the way another bird might hear it. It is amazing how much more complexity a bird's song has when you listen to it in this manner.

Here is a quick summary of some of the things he talked about:

• A Song Sparrow has 8-10 similar, but different songs . Note the change in the beginning of their song as well as the ending. When you see these different songs on a sonograph the differences become obvious. It brings to mind questions like-"Why do they switch songs?" "What does it mean?"


• Birds have different dialects in different areas of the country just like people do.


• In his opinion, Western and Eastern Marsh Wrens are totally different species. The DNA is different, and their songs are not even close to being the same. There is a line right through Nebraska where the two species split. A Western Marsh Wren can learn 3 times as many songs as an Eastern Marsh Wren.


• In Martha's Vineyard, Black-Capped Chickadees have different versions of the "Hey-sweetie" song (I call it the here kitty song). The Chickadees have 3 different versions of this song across a 20 mile stretch.-Why?


• The Three-wattled Bellbird (a flycatcher) have changed their song from 5,000 cycles per second in the 70's down to 2,000 cycles per second and know one knows why.


• Male Hermit Thrushes have about 9 different songs. Each time they sing a song they make sure that the next song is distinctly different than the one before. This is represented as a an up and down effect on the sonograph. When a second male Hermit Thrush enters the area, the two Thrushes very deliberately make sure that their songs are opposite on the spectrum from each other.


• Male Song Sparrows generally stop singing in August. When a female is injected with a hormone that tricks the male into believing she is still in breeding season, a in her vicinity will sing in any month.


• You can download free sonograph software from The Cornell Lab Of Ornithology.

I must admit that I once tried to read "The Singing Life Of Birds" but put it down before finishing it. There was more information than I wanted to know at the time. I'm definitely going to give it a second look. This seminar has inspired me to pay closer attention to vocal communication amongst birds. It can be another enjoyable aspect of birding, with the potential to learn something new.

Do you pay attention to the different vocalizations? Have you ever read "The Singing Life Of Birds?"