As spring progresses, and EVENING GROSBEAKS move through, here in southern
Oregon we will be listening for both types (Type 1 and Type 2) as they fly over
the forest and perhaps visit neighborhood feeders.
http://ebird.org/content/me/news/evening-grosbeak-flight-call-types-how-much-overlap-occurs/
Sounds are here.http://earbirding.com/blog/archives/1601
Good birding,Russ NamitzMedford, OR