Sometimes prespawn females will intentionally rub and bump their sides into a stump, log or firm bottom to loosen up their eggs in preparation for laying them. This may have been what they were doing while rolling on their sides. I have seen this as well.

I find when a female is not locked onto a bed I have a much better chance of catching the fish from a distance with a stealthy presentation. It seems like when they are just "hovering" around the bed they are difficult to catch when they are tipped off to my presence. My advice would be to remember the location of the bed and come back later, stay back as far as you can and still make a good presentation.

This scenario can be frustrating at times. Good luck.

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