I don't have an explanation for this.
This month alone, I've received over 1,400 image search requests (from Google Images [1]) for Andrew Jackson [2]. Going over the logs, I've see I also received over 1,400 requests for images of Andrew Jackson last month, but about an average of 30 or so from April through December, and over 200 in March, but that's when I first placed the image up.
Weird.