How do barometric pressure changes affect fish activity?

Stable barometric pressure can indeed increase fish activity, as it often indicates a consistent weather pattern that can create favorable conditions for feeding and spawning. Fish are sensitive to changes in their environment, and stable conditions typically lead to more predictable behaviors in many species. When barometric pressure is steady, it can mean that the water temperature and other conditions are also stable, encouraging fish to be more active.

In terms of the other options, significant drops in barometric pressure may initially cause fish to become more active in some cases, particularly just before a storm, but this isn't universally true for all fishing situations. Fish that are accustomed to stable environments may become unsettled with sudden changes. The notion that all fish increase their activity in low pressure is a misconception, as different species may respond differently. Furthermore, it's not accurate to say that fish are unaffected by barometric pressure; they can indeed be influenced by it in various ways, which is why the understanding of barometric pressure's effects is crucial for successful fishing.