A person or thing that is ruined; a GONER, gone goose: Just one more little push and she was a dead duck/ Unless somebody would start this mob to the sugar bowl, I was a dead pigeon(1844+)
The Dictionary of American Slang, Fourth Edition by Barbara Ann Kipfer, PhD. and Robert L. Chapman, Ph.D. Copyright (C) 2007 by HarperCollins Publishers. Cite This Source
Idioms and Phrases with dead duck
A person doomed to failure or death; a hopeless case. For example, If they can't find a heart to transplant soon, he's a dead duck.
A useless, worthless, or outmoded person or thing. For example, They didn't interview the outgoing senator; to the press he's a dead duck. Some speculate that this slangy term comes from an old saying, “Never waste powder on a dead duck,” first recorded in 1829.