The Summer Peak Period occurs as a body of water reaches maximum productivity in terms of plankton blooms, insect hatches, underwater weedgrowth, and swarms of fry. This dynamic period lasts just a week or so, perhaps two, but typically offers excellent fishing. The Summer Period follows, the longest period of the year for the southcentral and southern regions. Most of a fish's annual growth occurs during the Summer Period as bass feed heavily, but fishing success can be highly variable.

When water temperatures begin to drop in early fall, the Postsummer Period has begun. Cooler nights cause the shift, which can signal the beginning of a peak in bass fishing. The Postsummer Period lasts until fall turnover, which typically occurs in deeper lakes and reservoirs when water temperatures have fallen into the low 60F or upper 50F range. This Turnover Period is short, lasting until water temperatures have stabilized in the low to mid-50F range. This disruption in the stability of summer typically means difficult fishing.

The Coldwater Period follows turnover, as water temperatures continue to fall to annual lows. In northern waters, this leads to freeze-up, sometimes just a month or so later. And the annual cycle completes itself.

WINTER PERIOD SPECIFICS

Bass are cold-blooded creatures, more properly called poikilothermic, as their body temperature closely corresponds to surrounding cold water temperature. Bass behavior is strongly affected by seasonal shifts as well as immediate weather patterns.

During the Frozen Water or Winter Period, largemouth and smallmouth bass display the least activity of the year. They typically hold in the deepest water they ever occupy. For at this time, the depths are slightly warmer and more stable than water near the icy surface. Precise depth depends on characteristics of the body of water.

In natural lakes, bass move to deep flats or basins of moderate depth in 15 to 30 feet of water, often roaming slowly throughout a wide area. Smallmouths hold more tightly, often in discrete wintering holes. In large reservoirs, largemouths, smallmouths, and spotted bass may move even deeper, beyond 50 feet in clear waters.

Bass in ice-bound waters often form large groups where they feed and move little to conserve their dwindling energy resources until spring arrives. Though not feeding, bass can be tempted with a small jig or livebait. Few ice anglers target bass, but incidental catches are common in many lakes and river backwaters.

Largemouths are more active during the first few weeks after lakes first freeze, and again seem to move and perhaps feed more toward the end of the ice-bound season. In shallow lakes, declining oxygen content in bottom waters may force fish closer to the surface in late winter. In severe conditions, fish kills may occur, with the largest fish affected first.

Bass in rivers that freeze seek backwaters with adequate oxygen and protection from current. In some cases, deteriorating water quality forces bass to shift location in midwinter. Because the number of good backwater habitats is limited in many rivers, large concentrations of bass can form.