This whole thing got started in 1947 when Harry
Truman was president. And that has actually been a
source of confusion. Bill Clinton in his 1997
pardoning ceremony proclaimed that Truman was
the first to pardon a turkey. But that's not true. The
Truman Library issued a statement in 2003 saying:.."
http://www.npr.org/2015/11/25/457253194/the-strange-truth-behind-presidential-turkey-pardons