Jim Olson, center, poses with his children, Emma, left, and Trent. Trent was a bit jealous that Emma caught a bluegill during a recent fishing trip.

Finding clusters of bluegills hovering on fanned out “moon crater” clusters of their spawning beds might mean easy fishing today on southern Wisconsin lakes like Waubesa and Delavan.

But with the full moon reigning over the night sky tomorrow, these fish will likely move on by Sunday morning.

Moon phase plays a significant role in fish behavior.

A high percentage of trophy fish get caught within three days either side of the full moon. The full-moon period between now and Labor Day has special impact on flathead catfish and bluegills—likely other fish species as well.

I can only testify to the effect of moon phase on these two species after a lifetime of trying to prove my dad and grandpa wrong.

Both of these men were hardcore “river rats” as were their fathers before them. They found many natural truths in epiphanies like channel catfish spawning when “cotton” comes off of cottonwood trees and crappies spawning when lilacs are in bloom.

Other observations like geese flying by the calendar, ducks by the weather and flathead catfish more active during the day than at night during the summer full-moon period are a little more obtuse.

Don’t be surprised if those bluegills that have provided thrills for the past week or so are gone Sunday morning. They will be back on the beds in slightly deeper water a couple days prior to the full moon in July and August, moving on when that full moon rules the sky.

Lakes vs. rivers

These fish will be fairly easy to pattern all summer long in lakes and flowages across the state. But what about bluegills swimming in rivers? The location and behavior of panfish is almost easier to predict in rivers than it is in lakes in small streams like Sugar River, medium ones like the Rock and major rivers like the Mississippi.

I suspect few anglers have caught respectable messes of crappies and bluegills on Rock River because they haven’t taken the time to seriously fish for them. It’s much easier to find these “pannies” fishing in and around the weeds of most Wisconsin lakes.

Panfish don’t have much submergent vegetation to relate to in rivers like the Pecatonica or Yahara. Habitat is a little different in backwaters and running sloughs over on the Mississippi. But woody cover is a common thread for riverine bluegills and crappies in flowing waters across the state and beyond.

The primarily prey status of panfish in the food chain and forage base preference for benthic macroinvertebrates—a 10-cent description meaning bugs and other tiny critters—drive panfish to seek refuge tight within a tangle of woody habitats where they can skulk in relative safety from predators without fighting current while slurping zooplankton, insects and young-of-year baitfish, some of which would like to survive long enough to be called bluegills.

Feed at dusk

These fish will venture out of their cloistered haunts to slurp tiny foodstuff from the surface at dusk and into the night when a hatch is coming off on a sultry summer evening. But most of the time, turning these fish into a tasty sandwich means teasing them with a tiny morsel knocking at their door with a hook that will find wood more often than fish lips.

My ancestors had suitable tools for harvesting river panfish long before I adopted an unshakable belief that the only way to catch panfish is a $300 species-specific St. Croix panfish series rod.

Their gear was simple: a 10-foot cane pole with nine feet of braided Dacron line with a small light wire hook and a little bit of bait.

Snags are common

Getting snagged is part of the program if you’re fishing where the fish are. The light wire hook can be easily bent back to a functional shape. Nine feet of no-stretch line on a 10-foot pole often enables hoisting the panfish out of the tangle before it can flee to a nearby branc.

And using the tiniest pinch of bait ensures the quarry is more likely to feel steel than enjoy a dangle of free lunch.

Patience required

Not every river deadfall or driftpile will give up a nice mess of pannies. Not every tiny opening in a tangle of brush will give up fish when you find them. Hooking up requires the patience to slowly lower the hook close against the wood of every little opening between the branches until you find a “honey hole.”

Crappies usually suspend a little higher in the water column than bluegills, usually less than two feet below the surface. Bluegills tend to hold closer to the bottom. Maybe four feet down.

If you can resist the temptation to chase species that are much easier to find and catch on Rock River, the spots where you find finned treasure will likely produce for years to come.

Ted Peck, a certified Merchant Marine captain, is an outdoors columnist for The Gazette. Email him at tedpeck@acegroup.cc