Perch really do go on and off their diets. At times they eat sparingly, as though they’re fasting for a wedding or class reunion, wishing to fit into that special dress or mothballed cheerleader outfit. Binging comes more easily, though, eating half-gallons of ice cream in the middle of the night while watching favorite TV reruns.
Human diets change for reasons like stress, depression, health, and the quest for a sexier appearance. Perch do it for different reasons—none of them contemplative—mandated by nature. Perch play the dietary hand they’re dealt, making the most of available forage and environmental conditions that guide their behavior.
In this spirit, it’s reasonable to say that perch of the same stripe and size feed on what’s available and what biology instructs them to eat. Our tasks as anglers are to determine what’s available to consume and what forage the fish prefer at a given time, as well as what to present.
For this discussion, we turn to Brian “Bro” Brosdahl, a man at the top of his game when it comes to analyzing perch behavior and their responses to various presentations. Bro puts science and experience to answer the quandary of whether to fish big or small.
“Fish of the same size, even the same fish, hit baits both big and small,” he explains. “Sometimes, if they’re aggressive, you can drop a tiny jig and waxworm or a big fat jigging spoon and get the same fish to strike. But usually, it seems individual fish prefer a certain size and type of bait.”
To discover what bait to use and when, one must first understand available forage. This is the nexus of perching knowledge. “Some lakes have ‘bug bites’ and others ‘baitfish bites,’” Bro says. That status can run vice versa on the same lake at different times, too.
Some lakes are largely aquatic-insect oriented. They might feature freshwater shrimp (scuds). The house specialty on others might be bloodworms (midge larvae), mayfly larvae (wigglers), or even scads of immature crayfish. Those are Bro’s “bug lakes.” Other bodies of water showcase baitfish, perhaps lake shiners or darters, or young of the year, be they miniature perch or juvenile fish of another species. And there are lakes that have almost every type of bait imaginable, which can cause perch to be picky about what they select from the buffet.
Bro says, “Size of the bait does not dictate the size of fish you catch, when it comes to perch. It’s more important to match the conditions to catch the biggest fish in any given system.”
Thin is In
On any given natural lake, perch can occupy depths most would consider unworkable—like 2 to 4 feet of water. That can mean 2 feet of ice and an accompanying 2 feet of water, or less.
What drives perch to this extreme environment is the availability of food and enough protective cover to last another day. And the eats are most often baitfish, but other aquatics, including scuds, mayfly larvae, and bloodworms, can inhabit these shallow zones. “Young-of-the-year perch can be all over the place, darting around the weeds. Oh, yeah, and darters, too, and those little sculpin-looking fish you see zipping around the weeds. Perch eat them all.”
