Quote Originally Posted by Byron haugh View Post
Tad,
Ive found several contradictory statements on this on the web. Some say caddis others say not. Guess the bottom line is all insects are affected by pollution. Wish I ould locate my copy of "Caddisflies" by Gary LaFontaine. I believe he discussed this issue in his book.
There is some excellent information on aquatic insect tolerance at http://course1.winona.edu/nmundahl/Segment2.pptx (you'll need PowerPoint to view this information). Note that he shows staoneflies and mayflies in the most sensitive group and caddis flies a step down (being somewhat more tolerant of pollution). However it also appears as though there is quite a bit of variation within both mayfly and caddis species -- eg, Baetidae are more tolerant than Ephemerella.