http://nhpr.org en http://nhpr.org/post/spectrum-birdsong <p>Mid-May is like rush hour in the bird world.&nbsp;Migrants have returned for the nesting season and the air is full of birdsong.&nbsp;As you might guess, birdsong is as varied as birds themselves.&nbsp;In fact, birdsong is defined generously to include any and all sounds they make with territorial or courtship intentions.&nbsp;Let&#39;s start with a traditional vocalization and then branch out.&nbsp;&nbsp;</p> Fri, 18 May 2012 04:00:00 +0000 Chris Martin and Francie Von Mertens 5027 at http://nhpr.org Spectrum of Birdsong