Bass don't move to deep offshore structure in summer because the shallows get too hot. Nor do they want to escape from whining jet skis or splashing kids. Bass abandon the bank because they find the best feeding opportunities on deep offshore structure.
Opportunistic largemouths occupy different habitats within a particular body of water -- some range around docks and marinas to pick off unwary panfish or lurk in thick woody snags or in matted vegetation; others patrol weedflats for preyfish and crawdads; pods of bass use the mouths of feeder creeks as ambush zones; and they forage on the vast schools of shad that waft through the open areas of impoundments from May through September.
In most impoundments, from Ohio to Alabama and Texas, gizzard and threadfin shad offer such a plentiful food resource that most of the adult bass population rely on them. And the fish that do intercept shad on offshore structure tend to acquire that football-like stature that indicates good living, and always helps out at weigh-in time. Most of a lake's lunker bass also follow this program, bulking up for the next spring's spawn.
During summer, shad wander offshore, seeking dense blooms of plankton, often with little regard for structure. You may watch a horde of shad dimpling the surface while the graph reveals other clusters in the 20-foot range. And at times, groups of bass hound these nomadic baitfish, surfacing in a feeding frenzy at unpredictable times and places.
But it's not in the nature of a black bass to feed this way. That's the specialized technique of the true basses, the Morone clan -- stripers, white bass, and hybrids (wipers). They instinctively herd shad toward the surface, then slash through the school. When bigmouths, spots, and even smallmouths sometimes join the feast, a mixture of species can be caught. At times, too, schools of largemouths corner shad away from structure. But black bass play second fiddle to the other crew, in terms of efficient feeding in open water. As a result, largemouth schools generally include younger, friskier bass.
Black bass are by nature more structure and cover oriented, so those that inhabit offshore spots select structure adjacent to the open reservoir basin. They hold off structural elements or in cover on the structure, waiting for shad schools to pass within striking distance. Then they immediately move into feeding position.
Baitfish often loosely follow reservoir features as they feed in middepths above the thermocline, filtering from point to point along submerged river channels. Sometimes shad contact structure at random times, creating flurries of action during the day. Shad schools also move inshore during the evening and offshore early in the morning. When they pass major structural elements, a slaughter can ensue. And at times, these feeding frenzies occur almost like clockwork, with the three-hour periods surrounding dawn and dusk, often signaling the best summertime bite.
Manmade cues affect shad location and periods of bass activity, too, namely the power generation schedule at upstream and downstream dams. During the week, power companies tend to generate at predictable times during the day, to store power for peak demand during summer evenings. When water is released to turn the turbines, current increases throughout the impoundment.
Water movement makes baitfish school more tightly and hold close to structure, where current breaks occur. This change in baitfish behavior increases their vulnerability to predators, especially black bass. When water starts to move, a point or bar that produced little all morning may quickly come to life as the actively feeding bass strike a variety of artificials. On Saturday and Sunday, generation typically is less, providing tougher fishing for weekend anglers and the tournament crowd.
In natural lakes, too, offshore bass are ready to feed. North of the range of shad, favored foods are small yellow perch, bluegills and other sunfish, and crayfish. Craws roam the edge where the deepest growing plants yield to a hard bottom. They climb deep weedstalks, feeding on the leafy greens, and scuttle the bottom to eat small invertebrates and detritus.
Young yellow perch sometimes are so abundant that they almost carpet the bottom of mesotrophic lakes, from gravel shorelines out to 20-foot contours. When offshore bass key on perch, they spit the barred morsels as you land them or place them in a livewell. During summer, bluegills, particularly the hordes of 3- to 5-inchers that inhabit so many waters, tend to hold higher off bottom, sometimes just a few feet below the surface over 12 to 20 feet of water.
Small groups of bass slowly patrol this transition zone, casing the scene for edibles. The focus can be near the bottom when perch and craws are the target. When waiting for an opportunity to take a sunfish, largemouths suspend off deep weededges or structures like humps and deep points.