A duck on their back

Posted by RRC August 08, 2008 at 17:09In reply to A duck on their back posted by ESC on August 08, 2008 at 16:05:

I heard a phrase the other night. Someone was asked if they "had a duck on their back?" Whatever does this mean? Has anyone else ever heard this one?

I haven't.

7 google hits for "duck on your back". Some are accidental (punctuated differently, etc), one uses it in a similar way to "an elephant in the room" (ignoring something obvious), and 2 are playing games similar to Duck Duck Goose with pictures of ducks taped to someone's back.
I doesn't seem to be a commonly used phrase.