Many bass anglers find "structure fishing" a confusing concept. After all, it's one thing to read about some pro winning a tournament on an obscure ditch or offshore hump, but when it's you out there trying to find some channel dropoff a half-mile from shore and having to rely on your graph instead of your eyes to know where to cast — heck, it's no wonder there are a lot more weekend anglers pounding the banks than probing open water. To help clear up the mysteries of structure fishing, we sought input from Cincinnati, Ohio, BASS pro Joe Thomas, a four time Classic qualifier and veteran TV outdoor show host. Whether you're a novice or veteran structure angler, we're certain Joe's advice, presented here in his own words, will improve your catch rate. — Don Wirth
STRUCTURE VS. COVER
I often hear anglers speak of fishing "structure," like weeds, stumps or rocks, when what they're actually referring to is "cover." So before we delve into the mysteries of structure fishing, let's make sure we're on the same page by getting our definitions straight: "Structure" refers to the topographical components of a lake, including creek and river channels, points, flats, humps and submerged roadbeds. "Cover" refers to objects associated with these components, including submerged logs, standing timber, stumps, rocks, weeds and boat docks. Structure often has cover on it — a point may have a rockpile on the end; the top of a hump may be covered with weeds; a creek channel may be lined with stumps.
Because you can't see down into the water, and because many bass-holding structures are in open water where it's difficult to get your bearings, you need several different tools to help you visualize what a structure looks like before you can determine where bass will be holding on it, and the best way to fish it.
I use a combination of bass boat electronics, topographic maps, marker buoys and visual input when assessing structure. Before I ever get to the lake, I'll study a topo map to determine potential bass-holding areas, based on the season I'm fishing. For example, in spring, I'll note structures such as big flats and steep shorelines where bass are likely to spawn; in summer, deep channels, offshore humps, etc. Marking these potential hot spots on the map gives me something specific to look for while on the water.
Once I'm on the lake, I'll idle over the structure and use my Bottom Line graph to help me answer such questions as: How does the structure "lay" in comparison to the water surrounding it? Does it have a fast or slow taper into deep water? What kind of cover is on the structure, and where is it located? Is the cover thick or sparse? Are there baitfish on the structure? And, are there any bass on it?
If my graph reveals some hooks indicating bass on the bottom or holding tight to cover, or if I don't see any signs of life at all, I'll usually lower my trolling motor and fish the structure. But if I see bass suspending 4 to 8 feet or more off the bottom or above cover, I'll probably skip that particular structure for the time being, and return later to check it out again. Fish suspending over structure (and the cover associated with it) are usually much harder to catch than bass holding tight to the bottom or cover.
Marker buoys are so critical to structure fishing that I can't imagine offshore fishing without 'em. They allow you to visualize the shape of a hump and pinpoint its highest part, see how a creek channel snakes through a tributary arm, and determine exactly where that little concentration of stumps or weeds is on an otherwise bare ledge — in short, they provide a point of reference in an ocean of open water. Most bass boats have their transducers at the stern, so idle slowly over the structure, watch your graph, and then when you pass over some structural standout you want to mark, such as a dropoff, high spot or patch of cover, immediately toss a buoy back over the outboard so it marks this key spot exactly.
On a big structure, such as a creek channel bend, I may drop several buoys to delineate its shape. Then I'll back off and fish the spot, keeping another buoy on the front deck of my boat, right near my feet. When I get a bite, I'll kick this buoy overboard while I'm fighting the fish. Now I've not only pinpointed where the structure lies or where its main topographic feature is located, I've also got a directional guide for making future casts to that spot. This "kick-in" buoy is supercritical: I've seen countless times where my lure had to hit the structure from a certain direction, or the bass simply wouldn't strike it.
When scrutinizing deeper structures, such as channel dropoffs and main lake points, I'll use certain bottom-bumping lures as "probes" to help me visualize what's down there. My No. 1 structure-probing bait is a Lucky Craft Fat CBDR deep diving crankbait. It does a great job of tapping bottom and bouncing off cover without hanging up excessively, and helps me determine by feel what the bottom composition is like, where key cover concentrations and topographical changes are, etc. It also generates hellacious reaction strikes from bass, so I stand a good chance of putting some fish in my livewell while I'm learning the lay of the land. Other reliable structure probers include a Carolina rigged lizard, Texas rigged worm, and jigging spoon. Once I get a feel for how the structure lays, I may try other baits, but I normally rely on one of these four when I first start fishing the spot.
What separates a great piece of structure from a good one? Primarily I'm looking for "cover on structure" — stumps on a point, weeds on a hump, etc. How much cover does a piece of structure need to hold a good quantity of bass? Not much! A structure containing a small to moderate amount of cover can be much more productive than one with a tremendous amount of cover, because bass are concentrated in predictable "sweet spots" rather than spread out across a big area. The importance of cover-on-structure is relative to the kind of lake you're fishing. In a rocky highland reservoir, one lone stump can be a gold mine on a point, hump or gravel flat. (Note: For more info on fishing cover, see "Fish Cover Correctly" in last month's issue of Bassmaster.)
STRUCTURE FISHING TIPS
Here are some structures common to most reservoirs, and my recommendations for fishing them:
CHANNEL DROPOFF — The old creek or riverbed that flowed through the landscape before the reservoir was formed. Bass and baitfish use channels as migration routes. They're often best in summer, especially if there's some current present.
Method: Position your boat in deep water, about a half-cast out from the channel lip, cast a crankbait or Carolina rigged lizard onto the shallower ledge, and then work it out over the dropoff. Or, cast the lure at a 45 degree angle so it "slices" down the ledge and into deep water. Either of these is a more natural-looking presentation than sitting in shallow water and casting into deep water, and you'll hang up less.
POINT — These are multiseasonal structures, since they vary as to depth and trajectory. They serve as a bridge connecting deep, open water to the shoreline. Bass use points to move shallow in spring, then to back out deeper after spawning. In summer and fall, bass hang around points to prey on baitfish schools that gravitate to these structures.
Method: Most bassers target the end of the point exclusively; instead, work all around the structure, fan casting a crankbait or heavy spinnerbait from different angles. You'll often catch more bass from the sides than the end — they're usually steeper and have better cover on them. One side is often better than the other because of its proximity to a channel or current. Mudlines often develop on points on windy days, providing shallow concealment for bass.
HUMP (aka: saddle, submerged island) — Humps attract bass and baitfish from open water, especially in summer and fall. They're most productive in river-run reservoirs with a marked current flow.
Method: The top of the hump gets the most fishing pressure, but the largest concentration of bass is more likely to be on one of the sides or ends. However, always make your first casts to the top because fish located there are often spookier than bass holding deeper on the structure. Next, fish completely around the hump, giving special emphasis to the downcurrent end by casting into the flow and retrieving downstream, which is the natural route for forage to travel in a river. Try a crankbait, spinnerbait, worm or lizard.
ROADBED — A man-made structure, ranging all the way from a shallow rut in the bottom marking an old logging road, or the remains of a paved highway. Often lined with stumps, rocks or big chunks of broken-up asphalt. It may have a ditch on either side, which was once used to divert rainwater off the road. Bass will spawn on submerged roadbeds in spring, and will hold on them in winter as well.
Method: If the roadbed is narrow, slice-cast it with a crankbait at a 45 degree angle. If it's wide, approach it like a channel dropoff, positioning your boat deep and casting shallow. Pay special attention to ditches adjacent to the roadbed; bass often gang up in little depressions or bends in these "substructures."
FLAT — These "non-structures" don't look very fishy, but can hold large numbers of bass from prespawn through fall. They're often peppered with stumps, laydown logs, brush and weed patches.
Method: I like to wander across a big flat like a spider, casting a spinnerbait, medium running crankbait or lipless crankbait to isolated cover in all directions. Bass are often concentrated in one specific area of the structure; look for anything that can focus baitfish, such as a shallow ditch draining the flat.
BLUFF BANK — Vertical structure found in rocky reservoirs, often adjacent to a deep channel. Best in fall and winter.
Method: Bass often suspend around rock bluffs; these fish are easiest to catch when there's a stiff breeze blowing onto the structure. Retrieve a suspending jerkbait, crankbait, heavy spinnerbait or metal blade bait parallel to the face of the bluff, starting close and moving progressively farther out from the structure until you contact fish. Bass may also hang around rock rubble at the base of the bluff; try a drop shot worm rig or a jigging spoon for these deeper fish.
SLOPING BANK — My favorite springtime bass structure in reservoirs. They hold a ton of crawfish, and bass will spawn in little pockets and on ledges along them.
Method: Position the boat in deeper water and cast close to the bank with a jig-and-pig, medium running crankbait or suspending jerkbait, working the lure out into deeper water. Look for subtle changes in bank/bottom composition, such as where chunk rock changes to gravel — bass will concentrate on these transitions.
MORE STRUCTURE-FISHING TIPS
In structure fishing, timing is everything. Bass often move on and off specific structures during the course of the day, especially structures located offshore or adjacent to deep water. If the fish aren't there, don't waste time parking on the spot and waiting for them to reappear - leave it alone, then return later to fish it again. This is the strategy pro anglers use when making a "milk run" of similar pieces of structure scattered throughout the lake.
The most obvious feature of a structure, such as the top of a hump or the end of a point, may not hold nearly as many bass as a more subtle feature, such as a slight rise or depression in the bottom. Read your graph carefully to pinpoint these subtleties.
Areas where two or more structures intersect or occur in close proximity often hold large concentrations of bass. Examine your topo map for places where a channel intersects a point or runs along a sloping bank, a ditch snakes across a shallow flat, etc.
Your graph is important, but don't bury your head in it - look around you for bass-holding structures, such as roadbeds entering the lake, a dark patch offshore indicating a shallow hump, etc. Cruising the lake during winter drawdown will often reveal plenty of offshore structures that you can fish next season.
Use your knowledge of the seasonal movements of bass to dictate which structures you fish throughout the year. In April, you'll probably catch a lot more bass on a stump flat than a rock bluff. — Joe Thomas