A hot bite, going gangbusters a few minutes ago, is now seemingly dead. Crappies were hitting minnows on Aberdeen hooks before the float could even settle and stand up. One on every cast. Happens every year. At some point, a torrid bite dies as if somebody turned it off with a switch. More often than not, a brief examination of what's going on around the boat solves the problem.
Panfish can switch from one forage type to the next in an instant, a change caused by things we often can't see, such as a sudden migration of crustaceans, plankton, leeches, or insects, or a sudden "bloom" of minnows. Panfish may not be as selective as trout, but they're not stupid. If the water they're swimming in suddenly comes alive with little brown wormy things, minnows are off the menu for a while.
Sometimes nature gives us clues. When the air is clear of insects and suddenly gnats or midges are crawling on your sunglasses, expect the panfish bite to change, if it hasn't already. This is most pronounced in spring, and every spring when we begin to see bunches of flying insects for the first time (usually in the afternoon), switching baits can make all the difference. If fishing with minnows, especially, a switch to maggots, waxworms, or softbaits that imitate larval stages of insects almost always precipitates a faster bite when insects begin to hatch. A hatch can last only a few minutes or all day. When it dies, switching back to minnows, other softbaits, or leeches tends to increase the regularity of bites again.
In summer, with insects all around us all the time, a new hatch can pass unnoticed. In fall, hatches start to become rare, and most insect migrations take place near bottom. From June through November, the whys and wherefores of sudden changes in the panfish bite can remain entirely hidden from view. But it's possible to make informed guesses. When a hot bite suddenly dies, the question begging to be asked is: "What's the bottom of the lake composed of around here?"
SUBSTRATE WISDOM
Most anglers know that rock, gravel, and clay-bottomed areas can have a substantial crayfish population that should, at many points during a season, attract the undivided attention of crappies, bluegills, and perch. But what lives in the muck? How about in marl, silt, sand, or in combinations of these substrates? Rest assured, when panfish concentrate in any area it probably has a lot to do with bottom composition and what thrives on or in it.
For instance, some of the most common forage items for panfish during the cold months are bottom-dwelling worms called annelids (segmented aquatic earthworms). Another huge food source for panfish during the warmer months -- leeches -- are related forms of these annelids. Both can be found in greatest number wherever particle size in the substrate is relatively small, suggesting mucky areas. Some species of annelid do quite well in silt (0.6 millimeter particles and smaller), which includes the smallest particle sizes of all possible substrates. Rich, organic sediments (with finer particles in the .07 to .09 millimeter range) tend to harbor the densest populations of annelids.
