MDOspreyers,

I wanted to post that, for what it is worth, I now strongly believe that the flight calls some of us heard at Sycamore Landing on Saturday belong to the Townsend's Warbler, suggesting that it is still around and vocal.  To me, it also suggests that the bird may be moving around quite a bit, as from what I could tell it appeared to be flying quickly from the direction of the open river toward the large patch of tangles and shrubs that is across the canal from the path.  To me it sounded as if it actually went down into there somewhere, which was confirmed by another birder at the time (I don't know this person's name).  I am very familiar with the calls of birds in our area as well as other areas of the country, though my previous experience with TOWA vocalizations is admittedly nil.  This call was also apparently heard by Brad Beukema who posted on 3/12.

I did some research away from the "standard" bird call media such as Stokes, and found a couple of sites that seem to support what I heard.  The first, from Birdsource, gives a recording where the first part of the song is almost exactly what I heard, though I admit I missed the rising part of the call at the end.  The link for this recording is below:

http://www.birdsource.org/warblers/species/towwar/index.html

The lack of rising notes at the end may be explained by the apparent variability of the calls and song of the TOWA, as outlined in the below web sites:

http://www.birds.cornell.edu/programs/AllAboutBirds/BirdGuide/Townsends_Warbler.html#fig1
http://percevia.duncraft.com/db/birds_of_north_america_western/obj/155/target.aspx
http://www.nps.gov/yuch/Expanded/key_resources/birds/species_descriptions/towa_description.htm

The Cornell site points out that the song often begins on one pitch, which is what I heard in the field.  I think the important part to consider, after realizing that the vocalizations tend to be quite variable, is the pitch and buzziness of the call which sounds just like all the recordings I have heard.  I am not aware of any other wintering birds in the northeast that would exhibit such a call.  I would say that birders searching for the TOWA should keep their ears open perhaps more importantly than their eyes.  One San Diego listserv birder said also that the bird seems to be very reluctant to pishing, so this may do no good to find the bird.

Of course, I welcome any discussion about the info I presented here, and will not react strongly to discussion as long as it does not get personal.  I routinely take an interest in bird vocalizations, as I know how important it is to ID-ing as many species in the field during outings, not to mention its usefulness on Big Days!

My 2 cents,

Jay Keller,
Arlington, VA