I have been getting into bird songs lately. I live next to a park and there are many birds that sing songs in my street throughout the day. I noticed different birds sing at different times of the day and of course different birds sing in different seasons. It's actually pretty great that I am now starting to be able to identify birds when I go on walks by their calls. You tube has been particularly terrific in my new found interest! This morning we had a grey butcher bird singing for half an hour which was pretty wonderful.