I have one of these Cadillac Telescopic Fishing Poles that also work pretty well as a hiking stick and tent pole. I think it'd work pretty well for mountain lake and stream fishing. I also have a Coleman "Pen Fishing Rod":



These are very inexpensive and light too. Not the greatest fishing rod or reel, but I've caught enough fish using sticks, cane poles, and a bit of line to not worry about having top of the line stuff.

Of course, I also have some top of the line stuff from the 1980s when I used to fish a lot, but it's not well suited for backpacking.
_________________________
--

"You want to go where?"