Inside Angles: Enlightenment One “Bit” of Information at a Time

Feature articles in In-Fisherman take the reader down a road to understanding subjects about specific fish species. The smallmouth bass article in this issue, for example, digs deep into options for connecting with bass by using hard-won tactics that few anglers may have considered before. As we so often say, a little tweak here, a little trick there, and soon enough you’re fishing better than you have before.

Topics in a column such as those in Bits and Pieces take a different route to enlightenment about more diverse topics. Many puzzling issues have been addressed in the 40 years the column has run. Like how critical is it really that bass, both largemouths and smallmouth, be held out of water no longer than a moment or two after being caught? In several studies of the changes in blood chemistry as a result of being caught and held out of water for as long as 10 minutes, with water temperatures around 70°F, both species showed signs of stress, but no morality occurred. Reducing time out of water, especially when water temperatures are particularly high, is always a good idea, but not as critical as some anglers believe. 

Or like how much weight fish lose by being out of water or not being weighed promptly. As in, “The fish would have been a record if the angler hadn’t waited 8 hours to weigh the catch.” It isn’t uncommon to see suggestions that fish weight can drop by 5 percent to as much as 15 percent.

A recent column cited an instance of a marlin caught off the South Carolina coast that weighed 678 pounds (a state record) when it first hit scales, but 608 pounds 10 hours later, on an official scale. Apparently, the fish lost 70 pounds, or about 10 percent of its weight.

South Carolina biologists questioned the loss and tested two 400-pound marlin. One was left unprotected in hot sunlight, while the other was wrapped and iced. After two hours, the protected fish had lost 1.8 pounds (0.45 percent), while the other marlin lost 4.4 pounds (1.14 percent). The maximum loss after 15 hours was 2.1 percent of total weight.

So the near-record marlin should only have lost about 14 pounds. Later, a photograph revealed that the first scale had been misread by 70 pounds. In Texas, another test was made after anglers found a near-record largemouth floating dead in the water. Had the fish been a record before it died? Tests of dead bass held in water showed they gained only slight weight. So a dead bass would gain only slightly if held in water, and it would lose only slightly if held out of water, laying on a dock or placed on ice.

Among the most enlightening reports have been about fish tracking, something In-Fisherman pioneered. The first study ever written about anywhere was about muskies in West Okoboji Lake, Iowa. This study, conducted in the late 1970s, revealed that after spawning, fish roamed open water until distinct weededges set up in about mid-July. No wonder fish were hard to catch until later in summer, as anglers of the day usually targeted structural elements and generally didn’t consider that fish sometimes held in open water away from structure.

In another early report, largemouth bass were tracked in a lake in which weedgrowth was eliminated by grass carp. With little cover to relate to, bass used three depth zones: (A) inshore (0 to 7 feet), (B) middepth (7 to 11 feet), and (C) offshore (11 feet or deeper). Bass in each depth range used different types of cover and hunting tactics. Inshore bass usually stayed near shoreline trees and roots. One inshore fish stayed near piers. In contrast, four of the five middepth bass were near or under piers 40 percent of the time. These bass moved from pier to pier and aggregated with other middepth bass. Meanwhile, offshore areas were devoid of underwater structure. Bass there related to the bottom or roamed open water, suspending to feed on shad.

Thus, science indicated how bass might function after underwater vegetation is removed. It explains poor fishing after vegetation is removed, as many bass suspend away from obvious cover and are hard to locate, although “bank beaters” would still find some fish, as would anglers targeting piers and docks.

The report also affirmed information from other tracking studies—information largely overlooked or forgotten today—showing that bass (and other fish with large gas bladders) tend to stay in the same depth range day after day. Bass move to feed in local home ranges, but seldom shift depth more than a few feet. That is, deep bass stay in deep water and their activity periods are established by conditions at that depth. Shallower fish stay put, too, and have activity periods based on conditions there. As we know, depth and time of activity are key variables in patterning fish.

Many studies also clarified how fish make food choices. Pike in one study were given a choice of yellow perch, dace, sticklebacks, and fathead minnows. The pike ate the minnows first, then switched to sticklebacks and dace. Perch were least often targeted.

So then why are yellow perch the predominant prey in many North American pike waters? Apparently, pike (and other fish) often create their own prey environment, selectively eating prey species until hard-to-catch species dominate baitfish populations. Eventually, a somewhat balanced predator-prey population develops where harder-to-catch prey fish are most abundant.

Anglers often assume that it’s best to imitate the predominant prey species when choosing lures. Several articles in this issue suggest consideration of this tactic. But science suggests why it may at times be better to do the opposite, choosing a lure that looks different than the predominant prey and may be judged easier to catch than the predominant prey. Or it may peak the predator’s curiosity, causing the fish to sample the lure.

The road to understanding may be straightforward. Other times, the routes are circuitous and counter­intuitive. Just “knowing more” about various aspects of a subject we love is satisfying for most anglers. And the more “bits and pieces” of science we know and can relate to our fishing the better we should be at solving the everyday puzzles that we face when we’re on the water.

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