I'm not sure Gentlemen but I have heard a bit of info that might be the answer to my question as originally posted, one gentlemen posted that the trout in question were jumping clean out of the water trying to discharge there eggs, the trout are in a sense locked in the dam, they can not run up stream to breed, so I would think that is there answer as to how to discharge there eggs. I did take one trout for the table and when I cleaned it I found it to be full of eggs. Ed