When a fish is feeding on the bottom, it is usually feeding non selectively. It is sampling the drift to determine food from not food. Since trout do not have hands, it must sample with it's mouth.
Originally Posted by lastchance
Fish look for object that suggest life. This can be done in two ways. Soft hackles, even when dead drifted have hackles that move suggesting life. So parts of the fly that move suggest life.
The other way if for the fly itself to move. Things that move through or against the current suggest life because only living things can move that way. Things that are not alive must dead drift. So animation can provoke a strike.
If the fish are deep, fish them with weight as you would a nymph, but allow them also to rise up at the end of the drift with a Leisering lift or allow them to swing at the end of the drift.
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