Can Fish Sense Atmospheric Pressure Changes?

As a fisherman, I constantly hear of weird fish related theories and while I have noticed some relationship between fish activity and the barometer, I have no idea how they would be able to sense such small changes in atmospheric pressure or why it would matter to them anyway. So can they? And if so, how?

Well, I am not an ichthyologist but over the (very) longrun, a change of atmospheric pressure will change the equilibrium concentration of dissolved gasses in the water.

On anything smaller than a geological timeframe, I would be totally flabbergasted if barometric pressure changes do anything measurable to water at all, let alone something fish can sense.

It seems possible.