Electronic breakthroughs have enabled a greater understanding of the world of fish. Color sonars draw bottom contours and mark individual fish, while GPS allows anglers to electronically mark key spots, record routes, and consult digital contour maps as they drive the boat and troll. Underwater cameras let us inspect the underwater world, examine habitat features and how fish relate to them. In combination, these tools have changed the way we fish for panfish, making us far more efficient.

One consistent observation is the way fish tend to hold near some sort of edge. Panfish, particularly yellow perch, crappie, and bluegill all fit this pattern. You may spot a pod of big bluegills just outside the edge of a deep cabbage clump. Sometimes they’re holding close to the bottom, other times just under the surface. But they’re near some sort of edge.

As you scan the bottom, a small finger of rock appears, extending from a deep weedline, and you startle a few perch. Looking up, you may find crappies suspended above the hard-bottom spot surrounded by sand and silt.  Again, edges key location.

Types of Edges

Bottom-oriented and cover-oriented species make more use of physical edges for resting and feeding, so walleyes and bass often share these spots with bluegills. Weededges and bottom-type transitions are the most important edges in natural lakes. In reservoirs, other important physical edges include submerged treelines or brushlines, roadbeds, and creek channels.

Vegetation Edges: Weededges form where lake or reservoir depth increases and sunlight can’t penetrate into the depths. In some spots, bottom type shifts from sand or silt where plants can root, to rock or gravel, yielding weedless areas. Such deep weededges are high-percentage areas for big bluegills and crappies through summer and into fall.

The shallow side of a weedbed presents an edge as well. Inside edges are prime spawning sites for sunfish and sometimes crappie. Most larger panfish move deeper, though, once water temperatures approach summertime highs and baitfish and plankton are abundant on the edge of the main lake or reservoir basin. Here, other types of edges can be important.

Structure Edges: In reservoirs, structural edges often define the summertime homes of crappie, and sometimes bluegills and white bass, too. Submerged roadbeds are concentration areas for summertime crappie, as are the edges of creek channels where a sloping flat meets deeper water at the flooded stream bank, often adorned with timber. While relating to this edge, groups of crappies shift vertically with time of day. Toward evening, they may move near the surface to feed on young shad, and closer to the channel edge during the day. And when cold fronts buffet the lake, crappies often move into thick brush along the channel or drop deeper into the channel, but still relating to this edge.

Unseen Edges: Some edges aren’t as visible with an underwater camera. Current edges, temperature clines, and features like mudlines position panfish. In rivers and the upper portions of large impoundments, current brings prey and positions it. While shad tend to school in a narrow band in fast-moving water, white bass are powerful swimmers and can attack from any angle, scattering shad in all directions. At other times, whites instinctively find the current seam where fast water meets slack. They hold close to current, burning little energy to maintain position while waiting for baitfish to swim by. Casting along this edge, retrieving in a downstream direction, can be deadly.

Panfish are keenly sensitive to surrounding temperature and can follow gradients to find prime conditions for feeding, digesting, and resting. In summer, cool tributaries and springs bring milder temperatures, current, and oxygen that attract baitfish. In winter, these spots offer milder conditions that fish often seek.

Heavy rains in a watershed create murky conditions that begin at the upper end of an impoundment where most inflows occur. The stained or even muddy water gradually advances downstream as a mudline, forming a sharp edge where it meets clear water. The advancing murk pushes baitfish ahead of it, and this glut of food draws white bass and crappie, along with bigger predators like stripers, bass, and walleyes. On large windblown impoundments, wave action also can create shoreline mudlines that white bass favor all year long.

Chemical edges, particularly of pH and dissolved oxygen, dictate fish position, too. During summer, many ponds and small impoundments stratify thermally and chemically. Of interest to anglers is the gradual and often complete loss of oxygen in the depths of these waters by mid-summer. Even catfish are forced to suspend above the bad water or move to shallower banks. Defining this oxycline requires an oxygen meter; but if your minnows die when soaked under a float or bottom rig, you’re fishing too deep.

Highly fertile waters, thick with planktonic algae and vegetation, often suffer oxygen drops at night during summer. Photosynthesis ceases then and respiration by plants and animals, along with decomposition of organic matter, reduces oxygen. Early morning fishing can be slow, as fish are sluggish due to low dissolved oxygen. Action improves as the day progresses.

Perch Patterns

Big waters, many of which are great producers of hefty perch, can be intimidating—so much water for fish to get lost in. Savvy anglers find that edges often are the key to finding big schools of active perch occupying the deep rolling flats of Lake Erie’s Central Basin, for one prime example.

Craig Lewis of Erie Outfitters in Cleveland, Ohio, guides for perch and his clients rarely go home without a full bucket. “The most important edge for our perch is a bottom transition from rock to mud,” he says. “Perch often hold near the break, and at times they switch their feeding from the rock side to the mud side of the transition. In fact, one day they may be feeding on the rocky side, then switch the next day to mud.

“On Erie, the best transition areas have a sharp change in bottom content. At times, we’ve been anchored and anglers in the bow, fishing over mud, are catching fish, while those in the stern aren’t getting a bite. Perch are versatile feeders, but on Erie their favorite forage is the emerald shiner, and shiners typically school over mud bottoms. At other times, though, perch eat zebra mussels that colonize rocky areas.”