zugunruhe

Maybe that's why the birds felt an urge to migrate. ;->

and all these years I've been thinking it was a railwaymen's strike in Germany!

Four years on, my personal declaration of, and against, lexical ignorance runs from "abscissa" (Cormac McCarthy) to "zugunruhe" (William Fiennes, who admittedly provided a helpful contextual explanation of this, the migratory restlessness of birds). James Meek

This is one of those words that you look at and think, "Well that's from German".

The urge to migrate, especially as exhibited by captive birds.