Over increasingly large areas of the United States, spring now comes unheralded by the return of the birds, and the early mornings are strangely silent where once they were filled with the beauty of bird song.

Rachel Carson (1907-1964) American marine biologist, author, conservationist

Silent Spring, ch. 8 “And No Birds Sing” (1962)
    (Source)

This passage served as inspiration for the book title.