As anglers one intriguing aspect of fishing is solving the mysteries of nature. We try to figure out why we have epic fishing one day and bring home a skunk the next. There are countless variables that influence fish behavior – tide, current, water temperature, moon phase, time of day and salinity level to name just a few. Probably the most mysterious and debatable variable is barometric pressure.
In layman’s terms, barometric pressure can be thought of as the weight of the air, and it is influenced by weather systems. High pressure is generally associate with cloudless conditions and low pressure with rain, especially hurricanes. I am not aware of any scientific research that proves barometric pressure has a direct correlation to fish behavior, but it has a definite place in angling lore. Those that dismiss barometric pressure having an influence on fish point to the fact that water pressure is much greater than that of air, so even huge changes in air pressure are virtually undetectable underwater. Still, many avid anglers follow the barometer as a predictor of fishing success. Fishermen, by nature, are a superstitious crowd. It could be that barometric pressure’s influence on fish is just an old wives tale. I’m on the fence as to the direct influence on fish.
My observations generally show that quickly rising pressure causes a slow bite while falling or stable pressure make for better fishing. It may be that barometric pressure indirectly influences fishing by altering other variables. I find that the fish I target prefer low light conditions most of the time. It would make sense then that high pressure would slow fishing due to the bright cloudless skies that are caused by a high pressure weather system. Conversely, overcast skies caused by a low pressure system will prolong the transition from night to day which will likely make fish active during a longer time period. Quickly changing barometric pressure causes strong wind which can effect water clarity, tidal height, and current speed. Also, barometric change typically means changes in air temperature. The combination of wind and air temperature can cause a noticeable change in surface water temperature. Heavy rain from a large low pressure system can alter salinity and cloud water due to runoff. The are many other scenarios where barometric pressure indirectly influences fishing. In conclusion, fish have the ability to sense lots of variables that we as humans cannot; barometric pressure could be one of these variables.
One thing that I know for sure is that “you don’t know if you don’t go”, so let’s get on the water and wet a line!