With the river at low pool levels, a favorite predator tactic is herding baitfish up on the top of rocks in shallow water found on wing dams and similar rocky structures close to the main channel with some current.

Observation is the major key in taking advantage of this situation. From a half-mile away, gulls dive-bombing in for the wounded dregs left behind by finned predators can provide a clue that a banquet’s being served.

Fish tend to congregate in incredible numbers in a river system. You may travel for a mile or more to find that point of harmonic convergence where bait is just piled up and the feast is on.

A number of parameters define this phenomenon, which -- just like the river -- is ever-changing. Consistently cashing in requires a formula that includes time on the water and a good “search” bait like a crankbait or spinner.

Crankbaits that run down 6 to 8 feet can be deadly for Mississippi River smallmouths. The DC-8 Timber Tiger, Wiggle Wart and Bandit cranks are personal favorites.

Bait profile trumps color when you’re looking for smallmouths this time of year. On northern river pools natural colors tend to work better. Down on Pool 13, near Sabula, where I grew up, and points south, fluorescent hues often have an edge, because the water there is more stained.

On those waters north of McGregor, bluegill pattern and chrome/blue are both deadly right now, because these colors are close to the forage base of bluegills and shad.

From mid-September to mid-October, bluegills hold a regular convention on the rocks in some areas of the Mississippi, usually close to current, and their activity draws predators. Although the term “sure thing” can never be used when you’re talking about fishing success on the Mississippi River, the results can sometimes border on amazing if you know when and where to take advantage of this pattern.

Before and after this circus comes to town, shad are favored fare for smallies. One rod is always locked and loaded with a chrome/blue or chrome/black Rat-L-Trap to take advantage of this situation.

A spinnerbait is another handy weapon. On northern pools, blue/ white or purple spinnerbaits are usually most effective; from Dubuque south, chartreuse and chartreuse/orange baits tend to work better.

In exceptionally off-colored water, a big single blade has more “whump” and fish-attracting potential, but a tandem spinnerbait is generally the best way to go on northern River pools -- especially those lures with a willow-leaf or Colorado blade.

Many Hawkeye anglers have forgotten about in-line spinners -- a deadly tool for Mississippi River smallmouths between now and late October. My favorite in-lines are a No. 5 copper Blue Fox Super Vibrax and the Mepps Black Fury with white dots.

The Black Fury with white dots has only been on the market for a few years. But in this timeframe, anglers from Pool 11 north have come to realize this bait’s true “killer” status.

My nephew, Darrin Marcure, is one such believer. Several years ago we were testing this lure before it became available to the general fishing public. Darrin was just a kid then, and nothing is more fun than watching a kid wail away on white bass -- the bacon-saver for many Mississippi River fishing guides.

When you find white bass herding shad on the rocks in August, it’s a fish-on-every-cast scenario. But other predators are in the mix as well: Darrin’s fourth cast of the day was intercepted by a 6-pound 14-ounce smallie.

He killed this bass, which now hangs on the wall. As a farm kid, Darrin didn’t draw an allowance from his parents. This cost of mounting this fish was essentially a month’s chores and the entire proceeds of second-crop hay labor -- and to him, it was worth every drop of sweat.