Good questions. I’m certainly no expert, but I have had a lot of my fly fishing experiences on a river that does just that. Unfortunately. I’ve heard conflicting opinions on water flow changes, in terms of best and worst times to fish, but overall it does seem to hold true most of the time that fishing right around a sudden rise or fall in flows tends to shut the bite down for resident trout. For me, that has been noticeably moreso in the case of dropping flows, but I would hardly say that I’m fully convinced that would always be the case. I have experienced very good fishing a few times right as flows start to come up, presumably because it’s stirring things up and dislodging various menu items for bigger trout, but again this may well be somewhat situational.
Other issues you mention would also be potential factors, but can be addressed to some degree by what kinds of flies you fish, where, and how you fish them.
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