[Sanke56]

I haven't seen any wild carp this far north but they do exist in the US in Washington. I saw some in the snake river on a fish ladder once which flows into the Columbia river in Oregon. I think they may be introduced into those waters. I don't think they survive in the wild this far noth. Some people have introduced specialized carp inot some dugouts and irrigation systems here to control algae both the grass carp and the silver carp these introductions must be confirmed triploid and are sterile. They winter as long as they have enough oxygen and do grow quite large here they only feed above 50F.