Just like the title says. I haven't personally seen this fish, but I've had three different people tell me there's a fairly large comet goldfish living in a local river. Apparently they've all seen it. Is this a problem? I could try to catch it, I suppose, but I'm not sure I could manage to find it in order to catch it.
I haven't seen any carp in the river, just sunfish, a few trout, and bass. I don't think the goldfish can hybridize with anything.