This article is from the James Taylor FAQ, by Joel Risberg (firstname.lastname@example.org) with numerous contributions by others.
From Ethan Harvey (email@example.com):
He told the story at a concert I went to years ago, but I don't remember
all of it. He did own a pig named Mona, but he didn't shoot her. I think
he left rat poison out to kill the rats on his farm. Instead, Mona got to
the poison, and that was the end of Mona. But the shooting made for a better
song, I guess.