I had no idea this stuff was going on. I mainly do warm water fishing. The only trout fishing I have done so far was stocked trout in a small lake. I have been to upstate NY many many years ago trout fishing, but not fly fishing for them. I was not aware of all the stuff y'all have mentioned here. I knew that there were zebra mussels way up and away from me in the Great Lakes area I think I saw.... I had not heard of whirling disease, or New Zealand Mud Snails. Thanks for enlightening me.