Where Late The Sweet Birds Sang
By Kate Wilhelm
Where Late the Sweet Birds Sang is a post apocalyptic science fiction story in which humanity is surviving a worldwide ecosystem collapse due to cloning. It covers several generations start with the collapse of the world and shows the civilization that is created from it.
The title of the story is from Shakesphere's Sonnet 73 and was nominated for the 1976 Nebula and Won the 1977 Hugo award for best novel.