Just got the third invitation in a month to review a paper on marine microbiology. Looking up the publisher I found this. Little wonder my reply to them was a tad less polite than the previous two:
1. I'm a natural resource economist with no knowledge of biology.
2. This is the third such invitation. You're wasting your time and, worse, mine.
3. You're on a list of predatory publishers: http://scholarlyoa.com/2013/01/25/omics-predatory-meetings/
Stop wasting my time. I will now block your e-mails from my account.