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Smallmouth Bass Bass

Cold Front Smallmouths

by Matt Straw   |  August 23rd, 2012 0

Fishing line climbs off the water and hangs overhead. Static electricity makes potent shocks emanate from graphite rods, reel seats, bolts, and every conductor on board.

Those are second and third wake-up calls. You should already be out of there. But the fishing’s fantastic. Bass are almost jumping in the boat. In about 10 to 20 minutes the sky will lift, winds will pick up, the bite will disappear. The key question, of course, is: Why did you risk your skin for a bunch of fish? But anglers everywhere wonder, “Why did they stop biting? Fact is, nobody knows why bass and other species stop biting after a cold front passes, or why they often remain less active (especially big bass) for a few days afterward. But we have theories.

Cold Front Mechanics

Cold fronts are caused by moving masses of cold, dense air, which forces warmer air upward. Turbulence mixed with rising vapor can cause storms to form along the leading edge of the front. Cold fronts move in to two times faster than warm fronts and generally produce more dramatic changes in weather.

Crazy fluctuations in air pressure seem to affect bass most. Pressure decreases steadily as the front approaches, hits a low point as the front passes, then rises as dense, cold air settles in. Bass guides and pros have reported for years that, as a front approaches, bass move shallow and become highly active. If true (and it sure seems to be), it dispels the theory that bass are moving to equalize swim-bladder pressure. If so, they would move down in the face of decreasing pressure.

Conversely, according to that theory, bass should move up as pressure increases after the front passes. They don’t. In most cases they move deeper. Post-frontal conditions are also characterized by bluebird skies. Maybe bass try to avoid excess radiation and brightness? Perhaps. But nix the swim-bladder stabilization theory.

Another bit of conjecture: Zooplankton rise in low pressure, baitfish follow, and bass feed accordingly. When pressure declines, zooplankton drop into cover, baitfish stop feeding, followed by bass. But that doesn’t explain why bass remain less active for days afterward without incorporating other theories. If plankton stay in cover for days, so what? Bass could feed on crayfish, which don’t focus on plankton at all. But they don’t. They remain less active.

Some say bass are simply gorging then resting. Well, duh. They do that during stable weather, then put the feedbag back on the next day. Post-frontal bass don’t do that. Face it. We can’t address the physiological responses to cold fronts fish exhibit because we don’t understand them yet. What we do understand is fishing. We can continue to catch bass after fronts if we adhere strictly to the rules. After a front moves through, and for days afterward in most cases, the strike window of larger bass (over 4 pounds) shrinks to an area mere inches in diameter.

They won’t chase, they won’t even move unless you put a bait right on their nose. Even then it might take 5, 6, or more presentations on the same spot to tempt a bite. In response, baits must be moved incrementally. It’s slow, it’s tedious, and it’s impossible unless you have a good idea exactly where they live.

Tactical Approach To Cold Front Smallmouths

Targeting a river for smallmouth bass after a cold front is brilliant. Smallmouths in rivers may even continue to strike topwaters and cranks, but it’s more likely you need to slow down and swim plastic grubs or resort to drop-shot rigging. They might position less aggressively as well. Instead of facing into current in classic feeding positions at the head of a pool or eddy, they may tuck in behind current breaks or position between the center and tail-out of a pool.

In natural lakes and reservoirs, smallmouth bass turn off, but follow a relatively predictable routine. After feeding heavily in depths of 2 to 12 feet, they drop down as the front hits and pressure increases. They tend to tuck in tight on sharp drops and ledges along whatever structure they were using. It’s typical to find them at the base of the sharpest drop-off around reefs, points, humps, and channels in 12 to 25 feet. And they refuse to eat unless you politely insist.

Continued – click on page link below.

About Matt Straw

Matt Straw writes about fishing concepts and techniques for catching smallmouth bass, steelhead and salmon, panfish, and more. He continues to write features for In-Fisherman & annual guides.

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