Just put in the URL and it will tell you exactly which site is using the image. I found my Bulldog's pictures on several sites, ranging from puppy mills who are trying to pass him as one of their own, an auction site, a men's entertainment site (I don't get that one?), and various others. People have nothing better to do but to troll Flickr and steal pictures, it seems. It's now private, but clearly the damage has been done.
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