], who introduces us to the amazing world of trout-stream invertebrates.  She tells us how to gauge the health of a river by looking at the bugs, and also how we can all be citizen scientists and alert the authorities when we see a decline of important indicator species.   In the Fly Box this week we have the usual mix of difficult and easy questions, plus tips,  including: A great tip from a listener—don't try to fish while you are wading. Can I put an 8-weight line on my 7-weight Pflueger Medalist reel? A funny story from a listener on another way to break a fly rod As I get older my eyesight and finger dexterity are not what they used to be.  Is there an easier knot for attaching flies to my tippet? Why don't more people fish for chubs, and why are they considered a trash fish? Do you have any recommended cicada patterns? A listener who is also a toxicologist warns that not all fly-tying materials are harmless and gives tips on how to avoid undue exposure to them. I have trouble tying tails on size 18 and smaller flies.  Do you have any tips?