A newbie question: When you say the author retains the copyright, does that imply I should copyright it before I submit?
Your work is copyrighted the minute you set it in tangible and/or readable format, whether you type it into your computer or write it longhand on the back of a napkin. You don't need to do anything more.
What that reference in the info post means is that I won't assume copyright ownership of the piece. It will remain yours forever.
And speaking of the contest, TWO* more weeks to submit your story!
*Oops. When I wrote this, it was three weeks, and then I changed the post date and forgot to change the reminder date. Yes, deadline is Feb. 19th.