It was my understanding that Europeans introduced Carp into American rivers early on, for a plentiful commoner food fish. At that time they were unaware of the Catfish that were already teaming in our waters. OOPS. The buzz now is blue green algae. I read a story where it killed two dogs that accidentally ingested it while swimming. It's not even good to touch it they say. Google it, to see if it's in your area if you have water dogs.