Re: river question
Expanding on what noreaster said many flat deep stretchs of rivers have huge structures that don't show up in the flow of the water like they would in shallower stretches . Good time to explore these spots is when dry spells and other factors have left the river at low levels. At these times those big structures will become apparent as riffles and seams in the river and in extreme times even show themselves. A boat with a depth finder will show these spots that are not visible to the naked eye.
Some of the best flatwater spots are below rapids and damns . These spots become productive because they are resting spots and well oxygenated from the turbulence up river . And the bait that comes through the rapids and washes down to these flat area is disoriented and easy pickings for large predators.
Sometimes the slightest little change in the flat water areas could indicate structure and a place where fish will hold . Many times shad when migrating will be stacked like cord wood in areas like this as they rest to make there migration. Same goes for any of the other andromodous species.
Keen eye and trial and error along with time on the river will help you figure these spots out.
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