How does rain affect behavior of fish?

The fish bite better in the rain, don’t they?

If I had a nickel for every time I’ve heard that question, I’d buy you all a new reel. Most people have heard — or just assume — that fish bite better in the rain. While that sometimes (emphasis on sometimes) is the case, the reasons are not exactly because water is falling from the sky.

Fish, like all animals, are affected by the set of circumstances in their environment. The water temperature, sky conditions, barometric pressure, current and behavior of the forage base all factor into the relative activity of game species.

Rain typically creates a set of changes that can trigger increased activity all along the food chain, and thus the high-end predators — the species we seek to catch — click into a mode of increased movement and feeding.

The real factors at work, as mentioned previously, are the changes more than the precipitation itself.

For example, when it rains, the cloud cover increases. When the sky is cloudy, fish tend to move away from their bottom-hugging or cover-clinging behavior and roam the open water. That makes them easier to catch for anglers who don’t usually work the bottom of the lake or cast into the nasty tangles of brush and vegetation.

Rain also washes food into lakes and rivers, but a rather substantial amount of precipitation is required to reach the point where runoff picks up insects and worms and carries them to the waterway. Fish do sense the influx of new water and will swim toward rivulets and culverts to await the newly arriving morsels.

Sensing current

When a lot of rain falls, as it has in recent weeks, it can create current, which is a major determining factor in fish location. They sense current and use it to their advantage in feeding. In the fish world, current is like a conveyor belt that brings food much like a plant’s conveyor moves parts to the next workstation.

Rainy periods often are accompanied by low barometric pressure, which tends to be a better time for animal activity than high-pressure systems. Fish tend to kick back into a resting mode when the sky is piercingly bright as it is when the barometer is peaking, and get busy again when the needle begins its descent.

For that reason, the best fishing times often are the hours immediately before a rainstorm. The falling barometer is like a dinner bell for most of our favorite game species.

Oxygen levels

Fresh water entering the system also boosts the level of dissolved oxygen, another potential trigger factor, especially when the weather has been hot and stagnant. Oxygen can fall to levels low enough in the long, hot summers that fish are adversely affected. When dissolved oxygen begins to rise, the fish resume normal activity.

All of these factors combine to create changes in fish behavior that rain alone can’t cause. Together, they make it more likely that the fish will be moving and chasing, which tends to work in anglers’ favor.

So, do the fish bite better during the rain?

The answer, as you likely have concluded yourself, is “sometimes.” Understanding why rain can be a positive factor is important for those who want to take advantage of the conditions that accompany rainy weather.

New Highlandtown ramp open

The Ohio Division of Wildlife reports the new ramps and courtesy docks at Highlandtown Lake in southern Columbiana County are now open and the lake is refilling.

The lake had been lowered to allow for the repair work on ramps. Highlandtown, which is limited to electric motors, is a good panfish lake.

jwwollitz@aol.com