Here's the three-hour ambient drone soundscape I've edited together from over 70gb of field recordings for the 2010 RPM Challenge.
You can hear a variety of birdsong along with 'the wires' -- a large-scale aeolian harp built by Alan Lamb and Scott Baker for the Unsound Festival. See
http://hghlght.blogspot.com/2009/06/wired-for-sound.html for more on this amazing instrument.