I very well might be mistaken here, but I catch eels in a lake near me all the time and the closest saltwater is over 100 miles away down several creeks and two rivers. It would be impossible for them to go to the ocean and then back because they would have to climb up a huge spillway. I think they're American Eels, but I could be wrong.Definitely an interesting fish. I’d like to see one in a tank, probably hard to keep or just seen as undesirable as pets. I’ve never seen one for sale though, and I think they require full salt as adults. They just return to fresh to breed (I could be wrong). Would make a fun addition to a tank though.
But nothing compares to nice moray.?