There is no global warming.

There is no global warming. Nope. Joking aside, many things contribute to this, but trout and other cold water fish have been having a very hard time. Water temp doesn't have to change much at all to affect them. Why add more stressors to important food chain species?

http://www.foxnews.com/us/2016/08/19/popular-yellowstone-river-closes-after-thousands-fish-die.html
http://www.foxnews.com/us/2016/08/19/popular-yellowstone-river-closes-after-thousands-fish-die.html